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Showing papers in "Pakistan Journal of Agricultural Sciences in 2017"


Journal ArticleDOI
TL;DR: Economic importance of ornamental plants: Ornamental plants represent a great diversity of beautiful plants, including cut foliage, cut flowers, bedding plants, indoor plants, potted plants, bulbous plants, outdoor plants, which may be annuals, biennials or perennials in their growth habit and are economically important in horticultural trade, all over the world.
Abstract: Economic importance of ornamental plants: Ornamental plants represent a great diversity of beautiful plants, including cut foliage, cut flowers, bedding plants, indoor plants, potted plants, bulbous plants, outdoor plants, which may be annuals, biennials or perennials in their growth habit. Thus ornamentals bring aesthetic feelings to our surroundings (Riaz et al., 2002; Memon et al., 2013) and also economically important in horticultural trade, all over the world. They are also being used by the humans, even in the prehistoric times (Simpson and Ogorzaly, 2001) and the demand of ornamental plants for personal and ceremonial use has been increased. Cut flowers dominate among ornamental plants followed by flowering pot plants, tree and nursery plants, and flower bulbs (Lawson, 1996) but now the trend has been changed. The rapid rise is seen in the production of horticultural crops, including the ornamental plants (Janick, 2007), and covered the 42% of the total cash received from horticulture farms and 6% of all agriculture farms in Canada (AAFC, 2005). The total export of floriculture is increased by 1.9%, while 5.3% increase in case of cut flowers in 2011 (MNS, 2012). The ornamental plants (flowering and potted) having value of 32 billion euro were produced in the world in 2014 and Europe contributed 34.3% followed by China (15.9%) (AIPH, 2015). Area under production of flower and ornamental plants in Europe is 74 thousand hectare and Netherland is leading by sharing 35% of total area in 2013 (EUROSTAT, 2015). What are plant growth regulators: Plant growth regulators (PGRs) consist of organic molecules, produced synthetically and used to alter the growth of plants or plant parts. They have ability to accelerate or retard the plant growth. The hormone which is produced in plants is called as plant hormone and also known as phytohormone. Phytohormone is defined as, an organic substance produced naturally in higher plants, controlling growth or other physiological functions at a site remote from its place of production, and active in minute amounts (Thimann, 1948). PGRs sometimes confused with plant hormones, but there are certain differences among them as the term PGRs is used by agrochemical industry to indicate synthetic plant growth regulators, while plant hormones are a group of naturally occurring, organic substances which influence physiological processes at low concentrations (Davies, 2010). The growth hormone is the phytohormone and is essential to growth of organs as buds, stems, roots, fruits, and so on by cellular enlargement, both in length and in width, while growth regulator referred to organic compounds other than nutrients, small amounts of which are capable of modifying growth (Leopold, 1955). The PGRs can be biostimulant or bioinhibitor and are active even at very low concentrations in plant cells and have ability to alter the growth and development. The plant growth regulators represent various categories as American Society for Horticultural Science Pak. J. Agri. Sci., Vol. 54(2), 327-333; 2017 ISSN (Print) 0552-9034, ISSN (Online) 2076-0906 DOI: 10.21162/PAKJAS/17.3659 http://www.pakjas.com.pk

28 citations


Journal ArticleDOI
TL;DR: In Pakistan, eggplant is cultivated on large scale, but it lags behind many countries in terms of productivity, and the infestations and losses caused by the pest vary from location to location and season to season.
Abstract: Eggplant (Solanum melongena L.) also known as brinjal and aubergine is an important solanaceous vegetable and is extensively cultivated in South Asia (Bangladesh, India and Pakistan) which constitutes about 50% of the total area under eggplant cultivation in the world (Alam et al., 2003). Among all the summer grown vegetables with semi-perennial nature, eggplant is almost available throughout the year and is consumed in various forms by all classes of people. It has high nutritive value and contains all the essential minerals, vitamins and amino acids. In Pakistan, eggplant is cultivated on large scale, but it lags behind many countries in terms of productivity. Several factors are responsible for low productivity of eggplant in Pakistan (Hussain et al., 2014, 2016; Iqbal and Mukhtar, 2014; Kayani et al., 2017; Mukhtar et al., 2013a,b; 2014, 2017a,b; Shahbaz et al., 2015; Tariq-Khan et al., 2017). Among biotic factors, eggplant shoot and fruit borer (ESFB) (Leucinodes orbonalis Guenee) is considered by far the most damaging pest of eggplant (Taylo et al., 2016). The pest is active in moderate climates throughout the year. The females lay approximately 250 eggs one by one on developing fruits and young shoots of eggplant. The caterpillar is pink in color and is covered with sparsely distributed hairs all over the body. Fully grown larva measures about 20 mm long and pupates in a tough silken cocoon. The entire life cycle is completed in 3-6 weeks. There are five overlapping generations of the pest in a year. Severe damage to fruits and shoots is caused by the larvae of the pest. The petioles, midribs of large leaves and young tender shoots are bored by newly hatched larvae. Due to larval activity, translocation of nutrients towards shoots is affected. This causes withering and drooping of shoots, resultantly the growth of eggplant and size and number of fruits are significantly reduced (Atwal and Dhaliwal, 2007). The larvae then enter into young fruits, make tunnels and start feeding on internal tissues. The tunnels are clogged with frass and render the fruits unmarketable (Alam et al., 2003; Mainali, 2014). Sometimes, secondary infection by bacteria causes rotting of fruits and further deteriorates the quality of fruits. The pest is a serious threat due to its high reproduction, fast turnover of generations and tremendous damage. A single larva is enough to damage 4-6 healthy fruits (Jayaraj and Manisegaran, 2010). The infestations and losses caused by the pest vary from location to location and season to season Pak. J. Agri. Sci., Vol. 54(1), 65-70; 2017 ISSN (Print) 0552-9034, ISSN (Online) 2076-0906 DOI: 10.21162/PAKJAS/17.5282 http://www.pakjas.com.pk

26 citations


Journal ArticleDOI
TL;DR: The use of biostimulants to enhance the yield and quality of the bell pepper fruit has been reported in this paper. But, there are very few reports on the use of BIM to improve the quality and yield of the fruit.
Abstract: Bell pepper (Capsicum annuum) is the most important crop in solanaceous family after potato and tomato (Mahmood et al., 1999) and is famous throughout the world due to its high nutritional value (Kelley and Boyhan, 2009). In Pakistan, bell pepper is popular crop among farmers of peri-urban areas around big cities. While area and production under bell pepper is 66500 ha and 191800 tons respectively (GOP, 2010). Bell pepper is such an important food crop that its improved quality and production is of prime interest. Yield and quality of fruit depends on various preand postharvest factors which include environmental conditions, harvest maturity and post-harvest factors (Serrano et al., 1996). Many research groups are struggling to enhance quality and yield of bell peppers. For this purpose chemicals and hormones had been in use for many decades but now round the globe health concerns are increasing among people. Demand for chemical free and safe food is increasing day by day. These emerging concerns are leading towards use of biostimulants which are food grade chemicals and also known as GRAS (Generally regarded as safe) chemicals for producing food crops. Although significant amount of work has been reported on enhancement of quality of bell pepper through use of mineral nutrition, there are very few reports on the use of biostimulants to enhance the yield and quality of the bell pepper fruit. GRAS chemicals are not only capable to enhance yield and quality of fruits and vegetables but they also improve plant health by controlling diseases. Chitosan (CHT) is a biodegradable compound found naturally and is derived from crustaceous shells. Chitosan has proven to be beneficial to control several diseases of horticultural crops both in pre and postharvest stages (Banos et al., 2006). Foliar-applied chitosan increased plant growth, yield and quality of bean plants (Sharifa, 2013), radish (Farouk et al., 2008) and cucumber (Ghoname et al., 2010). Salicylic acid (SA) is one of the most important phenolic compounds, found in several plants. It is considered a hormonal substance which plays a vital role in regulating plant growth and development (Wang et al., 2006). SA is also effective to regulate important physiological processes of plants like growth and development, membrane permeability, ion uptake and transport (Simaei et al., 2012). It acts as bio-messenger or signaling agent in plants which promotes tolerance against several biotic and abiotic stresses (Horvath et al., 2007). Low concentration of salicylic acid has indicated increase in yield and quality of strawberry plants (Kazemi, 2013). Salicylic acid can also play a significant role in plant water relations, photosynthesis and growth (Arfan et al., 2007). Plants of cucumber and tomato when sprayed with lower concentrations of SA showed Pak. J. Agri. Sci., Vol. 54(2), 311-317; 2017 ISSN (Print) 0552-9034, ISSN (Online) 2076-0906 DOI: 10.21162/PAKJAS/17.5653 http://www.pakjas.com.pk

26 citations



Journal ArticleDOI
TL;DR: This study has been designed to investigate the effects of different irrigation frequencies on corn growth and a comparison was made between different rates of indigenously developed water Pak.
Abstract: The population of Pakistan is growing rapidly at the rate of 1.92% and is expected to reach 320 million by 2050 (GOP, 2015), posing challenges for meeting sharply growing water and food demand. This food demand can only be achieved by shifting from conventional to conservation agriculture by improving water use efficiency. Drip irrigation, being a proven technology, has offered special agronomical, economical, and agro-technical advantages for efficient use of water and fertilizer (Tayel et al., 2008; Dagdelen et al., 2009; Mansour et al., 2013; Mansour et al., 2015; Biswas et al., 2015) and it can replace flood irrigation having 50% application efficiency with an efficiency of 90%. Along with water saving, drip irrigation can apply fertilizer efficiently by coupling fertigation with irrigation that ultimately increase crop yields. In drip irrigation, mostly water soluble fertilizers are used (Munir et al., 2004) as conventional fertilizers can clog drip emitters with suspended and un-dissolved particles. However, most of the water soluble fertilizers are being imported from foreign countries to Pakistan that’s why their market price is too high. There is a need to adopt indigenously developed water soluble fertilizers to decrease production cost and get better productivity. With increase in crop productivity under drip irrigation, there are some limitations with its use like salinity buildup in root zone. The problem of salts accumulation in root zone under drip irrigation becomes more severe with groundwater (saline water) that can ultimately affect crop growth. In Punjab, Pakistan use of groundwater, which is mostly saline in nature, for irrigation has approached to 50% of crop water requirement due to shortage of canal water (Shah, 2007) especially for regular water application to crops under drip irrigation. A conventional remedy, which is mostly used to leach down these salts from root zone, is to apply one to two flood irrigations during a cropping season, which can fall water productivity. Another potential approach to leach down these salts from root zone is through drip irrigation system itself by use of different irrigation frequencies (Amin et al., 2015; Anjum et al., 2014). It will create a healthy environment for root development for better crop production. The research work of Sacksa and Bernsteinb (2011) and Min et al. (2014) showed the feasibility of drip irrigation system for saline water under different irrigation regimes and alternate use, respectively. Keeping in view the above discussion, this study has been designed to investigate the effects of different irrigation frequencies on corn growth and a comparison was made between different rates of indigenously developed water Pak. J. Agri. Sci., Vol. 54(4), 855-863; 2017 ISSN (Print) 0552-9034, ISSN (Online) 2076-0906 DOI: 10.21162/PAKJAS/17.5726 http://www.pakjas.com.pk

18 citations


Journal ArticleDOI
TL;DR: Sowing time can play a vital role in achieving maximum seed cotton yield in a country like Pakistan where the climatic conditions varies in various agro-ecological zones, however, choosing the best time of sowing in a particular region can often be difficult.
Abstract: Transgenically modified cotton (BT cotton) expressing insecticidal protein derived from Bacillus thuringiensis Berliner, has recently been added in the existing cottonwheat cropping system of Southern Punjab, Pakistan. It is worth noting that in 2005 cotton growing season, adoption of BT cotton has increased to an area of 2.4 million hectares in China. Similar trend followed is being by the farmers of Punjab, Pakistan from 4% in 2005 to 70% in 2010 (Sabir et al., 2011). The addition of BT cotton reduced the number of spray operations on crop that cause the reduction of 40% pesticide usage with yield advantages of 30-40% (Men et al., 2003; Sadashivappa and Qaim, 2009). In BT cotton based cotton–wheat cropping system, farmers are intended to sow BT cotton earlier to get the maximum production of BT genotypes which are relatively fast growing and give better yield. Optimum sowing time ensures higher productivity of cotton which differs in divergent agro-climatic zones (Wrather et al., 2008). Early planted cotton initiates reproductive growth earlier and produces more blooms and set more number of bolls utilizing the beneficial rains and sunlight that typically occur in June and July (Pettigrew, 2002). However, sowing too early leads to poor stand establishment and poor early growth due to prevailing cold weather, and also caused the seedling diseases (Bange and Milroy, 2001). Sowing time can play a vital role in achieving maximum seed cotton yield in a country like Pakistan where the climatic conditions varies in various agro-ecological zones (Ali et al., 2009; Deho et al., 2012). However, choosing the best time of sowing of cotton in a particular region can often be difficult, as it is a decision that must strike a balance between sowing too early and enduring problems associated with cold weather or sowing too late and losing potential yield. Information about the entire growing season and comparative duration of key growth phases is imperative as both are vital determinants of final output of a crop under Pak. J. Agri. Sci., Vol. 54(2), 233-239; 2017 ISSN (Print) 0552-9034, ISSN (Online) 2076-0906 DOI: 10.21162/PAKJAS/17.4394 http://www.pakjas.com.pk

15 citations


Journal ArticleDOI
TL;DR: The increasing prevalence of intense temperature is becoming a limiting factor for crop production specifically for wheat crop and warrants the prerequisite of boosting its yield on per unit land area basis and negotiates wheat production under high-temperature environment.
Abstract: Wheat is the largest growing cereal around the globe. It is grown on an area of 222.24 million hectares with production of 737.83 million metric tons in world (USDA, 2017). Food security in Pakistan is affiliated with wheat production and consumption. In Pakistan, share of wheat in gross domestic product is 2.0% and in value addition 9.9%. It is cultivated on an area of 9.260 million hectares (Govt. of Pakistan, 2016). The increasing prevalence of intense temperature is becoming a limiting factor for crop production specifically for wheat crop. Over the years, wheat productivity is threatened by increasing climatic skepticism (Wang et al., 2015). Wheat production under changing climate has been an arduous task. Hence, it warrants the prerequisite of boosting its yield on per unit land area basis and negotiates wheat production under high-temperature environment (Trnka et al., 2014). As a temperate climate crop, wheat crop prefers to grow in cool temperature (Asseng et al., 2015). The temperature optima for terminal spikelet, anthesis, and grain filling for wheat are 12, 23 and 21oC, respectively (Innes et al., 2015). According to an assessment, every 1oC rise of temperature declines grain yield by 3-17% in Pakistan and India (Mondal et al., 2013). The higher temperature is foretold to rise further in future and terminal heat stress (˃35oC) deleteriously impacting grain yield in wheat (Wang et al., 2012). Exposure of reproductive stages to the higher temperature is known as terminal heat stress. Heat stress is of “heat shock” and “chronic heat” types. Heat shock is the abrupt and utmost increment in temperature above 35°C for duration of 4-5 days. Whereas, chronic heat stress is occurrence of moderately high temperature (2530°C) for the relatively longer duration (Li et al., 2013). Negative impacts of heat stress include photorespiration, pollen infertility, cellular dehydration, rapid phenology, declining availability of assimilates for grain filling, chlorophyll degradation, decreasing number and size of grains and eventually decline in grain yield (Ghaffari et al., 2015). The most important adverse effect of heat stress is generation of excessive reactive oxygen species (ROS) that leads to oxidation of lipids of cellular membranes (Hasanuzzaman et al., 2013). Consequently, plant synthesizes antioxidants to scavenge ROS. Plants also accumulate compatible solutes and osmo-protectants as a defensive mechanism to regain cellular redox balance and homeostasis. Antioxidants and compatible solutes develop heat tolerance and maintain growth (Kamal et al., 2017). Pak. J. Agri. Sci., Vol. 54(4), 817-825; 2017 ISSN (Print) 0552-9034, ISSN (Online) 2076-0906 DOI: 10.21162/PAKJAS/17.6040 http://www.pakjas.com.pk

13 citations


Journal ArticleDOI
TL;DR: It has become apparent for nations to take entrepreneurship as key agenda, address its prospects, viability, productivity, and create an environment which facilitate entrepreneurial activity and engender positive entrepreneurial inclination among youth.
Abstract: Entrepreneurship has recognized to globe as the engine; to generate business activity, jobs, and escort nations toward economic prosperity(Kautonen et al., 2010; Nabi and Holden,2008; Haq et al., 2012).No doubt entrepreneurship has more than a few veiled potentials to fetch underdeveloped and developing nations into stream of development with effective human resource utilization (Moriano et al., 2011).Entrepreneurship has built in characteristics for human resource development, credit generation for business activity, innovativeness, and makes obvious outcomes in improving quality of life (Scarborough and Zimmerer, 2003; Roxas et al., 2008).It has become apparent for nations to take entrepreneurship as key agenda, address its prospects, viability, productivity, and create an environment which facilitate entrepreneurial activity and engender positive entrepreneurial inclination among youth (Levenburg, 2008; Devonish et al., 2010).Entrepreneurship is a miracle and utmost virtue of the times to cutback poverty, swell earning hands and production, engage capital up-to its potentials, redistribute income in deprived sections, and boost further entrepreneurial activity(Pihie, 2012; Sommer and Haug, 2011). Universities are the preeminent forum in regional entrepreneurial environment. Being key stakeholder in education, knowledge, and innovation universities could exploit colossal support to new ventures (Shane, 2004; Edmondson and McManus, 2007). Nowadays entrepreneurship has come into the first mandate among universities however, policy makers, and academic researchers also reflective for it (Etzkowitz, 2001; OECD, 2007). Therefore, various universities in collaboration to the local governments are trying to establish technological based science parks led through innovativeness for encouraging youth to participate, learn, manage, and move toward start-up, ultimately outcome to support entrepreneurial activity and economy. For instance, MIT, and Stanford had established their close links to industry, entrepreneurs in market, and had established a bilateral mechanism through both partners visit, learn, provide input, and share productive and innovative outcomes (Etzkowitz et al. 2000; Roberts and Eesley, 2009). Pakistan has world’s largest youth (68.4 percent below 30year age) could experience a new economic regime through entrepreneurial exposure among university graduates (GOP, 2015). This is a dynamic population may use as instrument to growth and prosperity for the country. To seed university graduates in entrepreneurial inclination may lead country with augmented economic activity, new jobs, innovativeness, human resource development, and improvement in quality of life. Presently, ongoing recession in almost all sectors of economy coupled with stagnant agricultural growth, and decreasing exports cultivate an increase in unemployment among youth. Universities are producing graduates in Pak. J. Agri. Sci., Vol. 54(4), 941-945; 2017 ISSN (Print) 0552-9034, ISSN (Online) 2076-0906 DOI: 10.21162/PAKJAS/17.5132 http://www.pakjas.com.pk

13 citations


Journal ArticleDOI
TL;DR: It could be argued that Turkey has fallen into a "middle-income trap" in the last 7 years as changes in growth rate and income led to significant changes in consumers’ consumption structure and consumption amounts.
Abstract: The ultimate aim of economic policies is to increase the economic welfare of all individuals and classes in society. The most important way to analyze the changes occurring in the welfare levels of individuals and social classes when the economy grows is to monitor the change in the distribution of income and consumption. Although increases in the rate of growth and per capita income provide a general sense of the changes in welfare, data about the distribution of income, consumption and poverty are the main indicators of the distribution of welfare increases that occur during the growth process for social classes and individuals (Caliskan, 2010). According to the Turkish Statistical Institute’s different year and different survey data, Turkey achieved a growth rate of 6.2% in 2002 but this rate declined to 2.9% in 2014. The average growth rate in Turkey from 2002 to 2014 was 4.93%. Economic growth simultaneously led to an increase in per capita income as well. Per capita income has increased at a fast rate, as it was $3.492 in 2002 and $10,444 in 2008. After 2008, there was no significant increase in per capita income. In 2014, per capita income was $10,404 in Turkey (Turkish Statistical Institute, 2015). Considering the developments in per capita income, it could be argued that Turkey has fallen into a \"middle-income trap\" in the last 7 years. These changes in growth rate and income led to significant changes in consumers’ consumption structure and consumption amounts. The per capita consumption of animal products is considered a significant criterion for comparing countries' levels of development (Sariozkan et al., 2007). Red meat, that plays an important role in providing animal-originated nutrients in terms of nutrition, is an indispensable food product for human health as well as a rich source of protein. While red meat consumption per capita in Turkey (veal, beef, sheep and goats) was 13.6 kg in 2014, it was 18 kg in the EU, 37 kg in the US, 41 kg in Brazil and 15 kg in Russia Beef and veal consumption in Turkey was 8.7 kg in 2010. However, it increased to 11.8 kg (an increase of 36%) by 2014. Sheep and goat meat consumption is between 1.5 and 2 kg, although it varies by year (Gul and Uzun, 2014). Chicken meat is one of the most important sources of animal protein that needs to be consumed for physical and mental development for a healthy and balanced diet (Inci et al., 2014). According to data from the World Agricultural Outlook 2015 published by the OECD-FAO, average chicken meat is consumed per person annually as follows: 43.2 kg in the US, 18.1 kg in the EU, 30.1 kg in Canada, 10.1 kg in China and 22.9 kg in Russia. In Turkey, chicken meat consumption (19.3 kg) is more than the average consumption in the EU (OECD, 2015). Annual average chicken egg is consumed per person annually as follows: 352 pieces in the Mexico, 343 pieces in the Malaysia, 329 pieces in the Japan, 285 pieces in the Russia. In Turkey egg consumption 197 pieces and Per capita Egg Consumption is the nineteenth rank in the world (YUMBIR, 2016). The estimation of demand systems for food has gained considerable research interest because of its elasticities and its roles in predicting marketing decisions and policy. For example, different models can use these elasticities in order model. In the calculation of agricultural subsidies, the impacts Pak. J. Agri. Sci., Vol. 54(4), 931-940; 2017 ISSN (Print) 0552-9034, ISSN (Online) 2076-0906 DOI: 10.21162/PAKJAS/17.5849 http://www.pakjas.com.pk

13 citations


Journal ArticleDOI
TL;DR: Arbuscular Mycorrhizal Fungi are antagonistic to the plant pathogens of the plant’s roots, this possible through different direct and indirect mechanisms of action, including competition for space and nutrients in the rhizosphere of plants creating networks of hyphae and roots blocking pathogen transmission.
Abstract: The major phytosanitary problem in the cultivation of pepper plants (Capsicum annuum L.) worldwide is the wilt caused by Phytophthora capsici Leonian (García-Rodríguez et al., 2010). This oomycete can cause losses of up to 80% in fruit production (Li et al., 2007). Excessive application of biocides, mainly chemical, to combat this disease can cause damage to human health and the environment. In addition, this pathogen oomycete can generate resistance even to new fungi such as the pyrimorph (Pang et al., 2013). Alternative handling of this disease comprises biological control using microorganisms that are antagonistic to the pathogenic agent (Segarra et al., 2013). Arbuscular Mycorrhizal Fungi (AMF) are antagonistic to the plant pathogens of the plant’s roots, this possible through different direct and indirect mechanisms of action (Abdel-Fattah et al., 2011; Jung et al., 2012). Mechanisms of direct action include competition for space and nutrients in the rhizosphere of plants creating networks of hyphae and roots blocking pathogen transmission. Al-Askar and Rashad (2010) showed that, in roots colonized by Glomus mosseae, Glomus intraradices, Glomus clarum, Gigaspora gigantea, and Gigaspora margarita in common bean roots, arbuscular mycorrhizal colonization significantly reduced infection by Fusarium solani. These fungi can change the patterns of root exudation, which indirectly promotes the establishment of beneficial microorganisms through qualitative and quantitative changes of their populations in the rhizosphere (Lioussane, 2010). Other mechanisms of indirect action of AMF in the bioprotection of plants against disease is Induced Systematic Resistance (ISR) (Haneef et al., 2010), through which the plant enters a state of alert that maximizes the switching on of its defense mechanisms to counterattack the pathogens in any area of the vegetal tissue. In this regard, Ozgonen and Erkilic (2007) reported that mycorrhization with Glomus etunicatum, Glomus fasciculatum, and G. margarita reduced wilt severity in pepper plants; this was associated with the greater concentration of capsidiol found in mycorrhizal plants. This phytoalexin could be related with the delay of the development of necrosis by wilt (Sid-Ahmed et al., 2000). Other mechanisms of action against plant pathogens are include structural functional compensation in the roots of diseased plants (Vierheilig et al., 2008) and the maintenance of the redox equilibria during Oxidative Stress Pak. J. Agri. Sci., Vol. 54(3), 513-522; 2017 ISSN (Print) 0552-9034, ISSN (Online) 2076-0906 DOI: DOI: 10.21162/PAKJAS/17.4245 http://www.pakjas.com.pk

11 citations



Journal ArticleDOI
TL;DR: In arid to semi-arid regions, soils are often low in organic matter (<1%) and poor in plant available nutrients, so organic amendments have to be applied repeatedly to sustain soil quality.
Abstract: In arid to semi-arid regions, soils are often low in organic matter (<1%) and poor in plant available nutrients. In prevailing soil and climatic conditions, crop plants use 50% or even less nitrogen (N) of the applied fertilizer and remaining is lost through denitrification and volatilization from the soil system (Khan et al., 2014). Despite of having high total phosphorus (P) contents (Muhammad et al., 2008), due to the formation of insoluble salts with calcium (Ca), phosphatic fertilizers do not satisfy nutrient requirements of crops (Khan and Joergensen, 2006). Pakistani soils have potassium (K) bearing minerals i.e. mica and feldspar (Bajwa and Rehman, 1996), however the increase in cropping intensity and introduction of high yielding varieties have also resulted in the depletion of plant available soil K reserves (Laghari et al., 2010). For the success of any soil management, it is crucial to maintain an appropriate level of soil organic matter and biological cycling of essential nutrients. Manure, mulches, cover crops and composts have been used effectively for supporting rapid cycling of soil nutrients through microbial activity and supplying nutrients to different crops (Trujillo, 2002). However, nutrient availability from these organic amendments depends on their decomposition rate and nutrient concentration (Reddy et al., 2005). The benefits of these organic soil amendments are, however, often short-lived, since decomposition rates are very high and the added organic amendment is usually mineralized to carbon dioxide (Mekuria and Noble, 2013). Organic amendments therefore have to be applied repeatedly to sustain soil quality. Agricultural wastes are important in soil agro-ecosystems as they add organic matter and ultimately provide essential plant nutrients i.e. N, P and K. When these wastes are used to produce biochar, they bring about an opportunity to be used as a sustainable soil amendment. It may help to avoid further reduction of soil organic carbon (Gaskin et al., 2008) and prevent increased fertilizer-use (Widowati and Asnah, 2014). Pyrolysis is the combustion of organic waste materials in complete absence or partial presence of oxygen, leading to the Pak. J. Agri. Sci., Vol. 54(1), 107-115; 2017 ISSN (Print) 0552-9034, ISSN (Online) 2076-0906 DOI: 10.21162/PAKJAS/17.5102 http://www.pakjas.com.pk

Journal ArticleDOI
TL;DR: This study focuses on two insects that are Trogoderma granarium and Tribolium castaneum, a serious pest of stored grains and their products that are under attack of a wide range of insect pests in stored foodstuffs.
Abstract: Storage of cereals and their products is a vital part of postharvest operations, through which food commodities passes from its way from farmer field to the ultimate consumer. Annual post-harvest losses of stored cereals due to various biological factors in the storages range from 10-20% of overall production (Phillips and Throne, 2010). As in field crops, the stored foodstuffs are under attack of a wide range of insect pests such as, Trogoderma granarium, Rhyzopertha dominica, Tribolium castaneum, Sitotroga cerealella and Sitophilus spp. These are of economic importance because they feed on a wide range of stored cereals and their products (Arbogast, 1991; Khan et al., 2010; Udo, 2011). The current study is focused on only two insects that are Trogoderma granarium and Tribolium castaneum. Trogoderma granarium (Everts) is a serious pest of stored grains and their products (Burges, 2008; Mark et al., 2010). It has a great economic importance, due to its capability to cause huge loss through ravenous feeding and heating of grains and to withstand starvation in larval stage (Rees, 1998). Similarly, Tribolium castaneum (Herbst) is most malicious and cosmopolitan pest having an extensive association with human beings stored food (Via, 1999). Both larvae and adults cause damage. In case of heavy infestation, the flour becomes mouldy and greyish having an unpleasant smell. Due to this infestation, flour becomes unfit for human intake (Atwal and Dhaliwal, 2005). Economic loss caused by this pest is estimated to be of 34% in stored millet and 40% in wheat flour (Ajayi and Rahman, 2006). The use of conventional insecticides and fumigants against insect pests of stored commodities has been resulted in Pak. J. Agri. Sci., Vol. 54(3), 589-595; 2017 ISSN (Print) 0552-9034, ISSN (Online) 2076-0906 DOI: DOI: 10.21162/PAKJAS/17.5088 http://www.pakjas.com.pk

Journal ArticleDOI
TL;DR: It was found that ten out of seventeen isolates from chickpea had positive nitrogen fixing activity but at varying levels and the range of fixed nitrogen was 136.666 to 303.666 nmoles C2H2 reduced/h/mg protein.
Abstract: Author(s): Zafar, M; Ahmed, N; Mustafa, G; Zahir, ZA; Simms, EL | Abstract: There are various mechanisms through which plant’s growth and yield can be promoted by plant growth promoting rhizobacteria (PGPR) that reside inside the soil. The use of pesticides, chemical fertilizers and other supplements could be replaced by PGPR. There are various substances produced by the rhizosphere microorganisms that are important for growth promotion as they affect morphology of plants indirectly. Their nodulation activity, biofilm formation, root colonization were observed and characterized for solubilization of phosphate, production of indole acetic acid and fixation of nitrogen. It was found that ten out of seventeen isolates from chickpea had positive nitrogen fixing activity but at varying levels and the range of fixed nitrogen was 136.666 to 303.666 nmoles C2H2 reduced/h/mg protein. Bacterial isolate CM1 showed maximum nitrogen fixation ability. Thirteen isolates produced IAA in the range of 3.833-18.100 µg/mL. Bacterial isolate, CM1 produced maximum indole acetic acid. Among chickpea bacterial isolates, sixteen were positive in phosphate solubilizing ability while only one was negative. Range of phosphate solubilization among chickpea isolates was 4.533-12.333µg/mL. Maximum value for phosphate solubilization was observed in CM4. Potential root nodulating bacteria were identified using 16S rRNA sequence analysis. CM1, CM2, CM3, CM5, CM6, CM11, CM15, CM24 and CM25 were identified as Mesorhizobium ciceri while CM4 as Mesorhizobium mediterraneum.

Journal ArticleDOI
TL;DR: In this paper, Shakoor et al. quantified the impact of climate change on wheat crop in Pothwar region of Pakistan and revealed that climate change would going to be harmful for the wheat crop.
Abstract: Climate is a significant element which effect the agricultural production. Unexpected deviation in climatic variables can stanchly affect revenue from crops. A number of researches to identify reasons behind these changes came out with results that the changes stemmed due to proclamation of the greenhouse gases (GHGs). These progressively gather in the atmosphere around us and eventually become rich source of global warming (Aydinalp and Cresser, 2008). It is also evident that the developed nations of the world are main contributors of these emissions whereas developing nations have very little share in this. About 75%discharges related to GHGs are prompted by the developed nations (Farooqi et al., 2005). Climate change can be demarcated like “deviation in climate caused by anthropogenic and natural activities. This change can be sustained for a longer period of time (IPCC, 2007). Bringing the climate change phenomenon under the umbrella of economy of Pakistan, it seems to be much vulnerable and threatened. This is due to the fact that development in economic sector is stanchly hurt by disparity in comportment of climate variables. Nations where the economy is largely dependent on agriculture’s share in GDP are more vulnerable to climate change (IFPRI, 2010). To enumerate impression made by climate change on agronomic production is a complex procedure due to the uncertainties and doubt in forecasting regional climate changes and the reaction showed by crops in response to environmental changes (Roudier et al., 2011). This situation can become degradable even with the slight change or variation in the climatic components like temperature and rainfall (DFID, 2011). In almost all regions of the world extending from Africa to Europe, Asia to America climate is explicating changes in its patterns from the last few decades. In case of temperature, the trend is on increasing side while in case of rainfall or precipitation, changes or deviation has been identified in its pattern of occurrence, where in some regions, there is wide change in occurrence of rainfall. In the Northern European region, there is marked increase in the rainfall while for Eastern and Southern European rainfall has been decreased (Olesan et al., 2011). In a study by Shakoor et al. (2011), researchers quantified the impact of climate change on wheat crop in Pothwar region of Pakistan. The results revealed that climate change would going to be harmful for the wheat crop. Pak. J. Agri. Sci., Vol. 54(3), 561-566; 2017 ISSN (Print) 0552-9034, ISSN (Online) 2076-0906 DOI: DOI: 10.21162/PAKJAS/17.4194 http://www.pakjas.com.pk



Journal ArticleDOI
TL;DR: To reinvigorate agricultural sector government needs to formulate a holistic policy focusing mainly on capacity building of farmers by improving access to inputs and enhancing their skills through training, extension services, and effective e-communication of agricultural knowledge to increase productivity.
Abstract: Media has evolved as an effective form of communication in the contemporary world which has widely acknowledged catalytic impacts on the process of development. Agriculture constitutes a major chunk of Pakistan’s economy accounting for 20.9% of its total GDP and 43.5% of employment (Pakistan Economic Survey 2014-2015). Unfortunately, this major sector has been severely neglected by the successive regimes in power resulting in low productivity and failure to achieve required growth rate (Bukhari, 2016). The stagnation of agricultural sector is attributed to inadequate investments in research and development along with lack of agricultural education and extension system (USAID, 2009). Thus, to reinvigorate agricultural sector government needs to formulate a holistic policy focusing mainly on capacity building of farmers by improving access to inputs and enhancing their skills through training, extension services, and effective e-communication of agricultural knowledge to increase productivity an efficient strategy is to ensure awareness about disease free seed of high yielding variety, better agronomic practices, effective plant protection measures (Muhammad et al., 2002), innovative market systems and timely dissemination of relevant information. In this regard, conventional methods like extension services through extension agents are being replaced by usage of mass media (Riesenberg and Gor, 1989) which have surpassed other media in terms of efficacy (Mohammad and Garforth, 1999). Although the efficacy of mass media in agricultural information is widely acknowledged but its relevance is also questioned on account of the missing “hands-on component” i.e. practical operation and application of technology (Rola et al., 2002) which requires practical demonstration (Reid, 2001). But this can be compensated by strengthening and activating comprehensive extension services through local extension agents (Leary and Berge, 2006). Pakistan, after the liberalization of media in 2002 especially the TV sector, currently enjoys a vibrant media landscape (International Media Support, 2009) with TV accounting for three-fourth of adults (76.2%) viewership of which 69.3% belongs to rural Pakistan (Gallup, 2014). As for radio, Radio Pakistan and FM 101 alone covers 80% of Pakistan’s territory reaching 95.5 million listeners while 115 FM radio channels are functioning alongside (UNESCO, 2015) but figures on radio ownership are not confirmed as with the boom in mobile phone technology “actual access to radio is likely far higher” (Yusuf, 2013). Various studies have been done on the role of media in disseminating agricultural information in Pakistan. Shahid et al. (2007) in their research aimed at investigating role of print media in spreading relevant information found TV the Pak. J. Agri. Sci., Vol. 54(3), 711-715; 2017 ISSN (Print) 0552-9034, ISSN (Online) 2076-0906 DOI: DOI: 10.21162/PAKJAS/17.5751 http://www.pakjas.com.pk

Journal ArticleDOI
TL;DR: In this paper, the effects of these ubiquitous compounds are not only limited to human but are extended to environment (Anwar et al., 2011), due to their chemical properties, they pose significant impact on human health and environment even at low concentrations.
Abstract: Pakistan economy is largely dependent on agriculture. Directly or indirectly, 68% of its population is dependent on this sector. It contributes more than 21 percent of the total GDP, Gross Domestic Product (Joudejans, 1991). Pakistan’s soil is favorable for vegetable and fruit growth and varieties of fruits and vegetables are cultivated here. Vegetables and fruits are juicy so they are more susceptible to pest attacks and pesticides are used for their control. Pesticide is a chemical substance that is used to control, prevent, devastate and diminish any harmful pest that destroys crops. Agricultural pesticides that are deliberately used to escalate crop yield unfortunately are endowed with many latent and insidious adverse effects. Their persistence in the environment is the significant property as the transportation of these compounds can broaden the range of exposure to far beyond the immediate area of their use or release (Rodriguez et al., 2011). Studies revealed that organochlorine pesticides (OCPs) and polycyclic aromatic hydrocarbons (PAHs) are among the most concerning environmental pollutants due to their highly toxic, persistent and bioaccumulative properties (Zhonghua et al., 2016; Hussain et al., 2016; Yang et al., 2016). Therefore, the effects of these ubiquitous compounds are not only limited to human but are extended to environment (Anwar et al., 2011). Due to their chemical properties, they pose significant impact on human health and environment even at low concentrations (Liu et al., 2009). Pesticides when released into the environment have different environmental fate as they may fall into different environmental compartments such as in air, soil or water. When sprayed they may percolate into the soil layer and through soil may reach ground water (Harrison, 1990). Transportation of pesticide from their point of application to other unwanted areas is mainly through rain and wind which may harm that environment. Humans are exposed to pesticides through oral means either by ingesting contaminated food, by inhaling contaminated air or through dermal means. Duration of exposure and toxicity decides the effect of particular pesticide; which may be acute or chronic. Acute include nausea, diarrhea, dizziness, rashes, blindness and death. Exposure of pesticide to living beings may result in chronic effects like neurological deficiencies reproductive disorders and cancers. The trend of pesticide usage in Pakistan is more because climatic conditions are favorable for pest’s growth and most of the farmers often grow off season vegetables and fruits that are more vulnerable to pests attack. According to Punjab Private Sector Groundwater Development Project technical report 2002, in Pakistan more than 108 types of insecticide, 30 types of fungicide, 39 types Pak. J. Agri. Sci., Vol. 54(2), 355-361; 2017 ISSN (Print) 0552-9034, ISSN (Online) 2076-0906 DOI: 10.21162/PAKJAS/17.5057 http://www.pakjas.com.pk

Journal ArticleDOI
TL;DR: Soil salinity directly affects the soil structure by inhibiting the clump formation which makes the soil tight and impervious, and reduces the air and water holding capacity of soil, leading to reduction in growth and yield.
Abstract: World’s growing population leads towards increasing food demand and engulfs more land for housing development. Salinization is decreasing the world's irrigated land by 1-2 % every year, affecting badly in the arid and semi-arid regions (FAO, 2008). Productivity of the food, forage and fodder is also diminishing every year due to desertification and salinization (FAO, 2009). It is estimated that over 6% of land area of the world is affected by salinity, which is approximated to 800 million ha (FAO, 2008). About 400thousand-hectare land in Pakistan is rendered useless every year by salinity (Ghaffor et al., 2004. To respond to increasing demands of food, new technologies are needed to produce more from less land. Soil salinity directly affects the soil structure by inhibiting the clump formation which makes the soil tight and impervious. It reduces the air and water holding capacity of soil. Thus, plants may not receive enough moisture and oxygen to grow (Brady and Weil, 2002; Shober, 2015). High salts concentrations in soil solution also cause toxic effects to plants that ultimately disturb various biochemical and physiological processes which causes reduction in biomass and yield of various crops (Munns, 2002). In general, salinity affects plant physiology at whole plant and in particular at cellular levels through osmotic and ionic stress (Munns, 2002; Yadav et al., 2011). Above and beyond bringing about osmotic and ionic stress, salinity stress usually causes ionic imbalance that may decline the selectivity of root plasma membranes and develop potassium deficiency (Ahmad et al., 2006). The build up of high amounts of toxic salts in the apoplasm of leaf outcomes to dehydration and loss in the cell turgor that eventually demises leaf cells and tissues (Affenzeller et al., 2009) leading to reduction in growth and yield. Salt affected soils can be managed by adopting different ways such as by using deep tube wells which lower groundwater levels, leaching of excess soluble salts by using fresh irrigation water, flushing soils that contain salt crust at the surface, improvement by chemical application like gypsum, organic matter, acids (Murtaza et al., 2009; Raafat and Tharwat, 2011) and by means of biological approaches e.g. developing salt resistance cultivars, use of plant growth regulators, inoculating crop seed and seedlings with plant growth promoting rhizobacteria (PGPR) (Athar and Ashraf, 2009). However, physical and chemical means are either costly and hazardous to environment or impracticable. Among PGPR, rhizobia are the most studied plant growth promoting microorganisms which are environment friendly, economic and practicable (Tairo and Ndakidemi, 2013). Pak. J. Agri. Sci., Vol. 54(1), 97-105; 2017 ISSN (Print) 0552-9034, ISSN (Online) 2076-0906 DOI: 10.21162/PAKJAS/17.5388 http://www.pakjas.com.pk

Journal ArticleDOI
TL;DR: Pakistan depends largely on agricultural production mainly comes from irrigated land because it lies in the arid to semiarid region, where shortage of irrigation water is the most important limiting factor.
Abstract: Pakistan depends largely on agricultural production mainly comes from irrigated land because it lies in the arid to semiarid region. Agriculture still remains the second largest sector after services sector and contributing 19.82 percent to annual Gross Domestic Product (GDP) of Pakistan’s economy (GOP, 2016). Pakistan has been granted with abundant water resources by the nature. However, due to competing demands of water for domestic and industrial uses, only a part of irrigation water is available for crop production. The supply of irrigation water is further limited due to other factors as topographical, geological, melting of glaciers and limiting storage capacity of water. Further, the significant amount of irrigation water is lost in the system due to conveyance losses and traditional water application methods being employed at farm (Asghar et al., 2001). The major sources of irrigation water are river supplies i.e. canal commanded irrigated area is about 16.00 Mha in addition to small share of 4 Mha of rainfed areas. Now the situation has been changed, the irrigation water is becoming scarce as the water availability in Pakistan has approached about 1000 m3/capita, categorizing the country as a water deficit country (Hussain et al., 2011). Moreover, projections show that with the current pace of increasing population, water availability will reach 915 m3/ capita in 2020 (Bakhsh et al., 2015). Pakistan is facing a great challenge of food insecurity for its population of 195.4 million (GOP, 2016). Wheat is one of the leading cereal crop of rabbi season and the main staple food of the Pakistani people. Wheat contribution in value added is 9.9 percent and 2 percent in Pakistan’s GDP, respectively. Total area under wheat was 9260 thousand hectares during 2015-16 compared to 9180 thousand hectares in the last year. Among different cropping systems of Pakistan, only Cotton-Wheat and Rice-Wheat systems together account for 60 percent of the total wheat area whereas one third of the wheat area is covered by rain-fed (1.5 t/ha). Among different factors responsible to the low wheat yield, shortage of irrigation water is the most important limiting factor. The water availability in rabi season is estimated 32.9 Million Acre Feet (MAF), which is 9 percent less than the average normal water availability Pak. J. Agri. Sci., Vol. 54(2), 467-474; 2017 ISSN (Print) 0552-9034, ISSN (Online) 2076-0906 DOI:10.21162/PAKJAS/17.4860 http://www.pakjas.com.pk

Journal ArticleDOI
TL;DR: Heat stress has been observed to exert detrimental effects on various hemato-chemical parameters of birds, however, various techniques are being used in birds such as addition/supplementation of various products in poultry rations to ameliorate the effects of heat stress.
Abstract: Birds are able to maintain their body temperature within narrow limits (Khattak et al., 2012). An increase in body temperature due to higher ambient temperature or excessive metabolic activities may cause irreversible thermoregulatory changes that could be harmful for the existence of birds (North and Bell, 1990) and may cause a change in physiological parameters such as rectal temperature, diseases, metabolic disorders and losses (Ahmad et al., 2006; Anjum, 2000). As environmental temperature goes up, respiratory rate of birds rises causing higher losses of CO2 that causes increase in blood pH and disturbs acid-base balance (Toyomizu et al., 2005). Any change in acid base balance may cause alkalosis or acidosis, diverting the metabolic machinery used for homeostatic regulation rather than used for production (Carlson, 1997). Alteration in levels of CO2 can cause disruption in blood pH. Growth performance of broilers was found to be the highest when blood pH was 7.28, whereas a decrease in growth was exhibited when pH values were greater than 7.30 or lower than 7.20 (Nelson and Cox, 2000). Detrimental effect of heat stress on plasma electrolytes concentration has also been found to be similar in different species of birds such as in broilers (Mushtaq et al., 2005), layers (Ghorbani and Fayazi, 2009) and quails (Keskin and Durgan, 1997). Heat stress is also known to disrupt status of reproductive hormones of laying birds, secreted by the hypothalamus and ovary (Elnagar et al., 2010). Packed cell volume value of birds has shown an inverse relationship with high ambient temperature (Parker and Boone, 1971). Hypothermia (8°C) caused an increase in the hematocrits, whilst hyperthermia (30°C) caused a decrease in hematocrit value. High environmental temperature has also shown to cause a decrease in serum protein contents in birds (Anjum, 2000). Heat stress has been observed to exert detrimental effects on various hemato-chemical parameters of birds (Borges et al., 2004; Ekanayake et al., 2004). However, various techniques are being used in birds such as addition/supplementation of various products in poultry rations to ameliorate the effects of heat stress. Supplementation of sodium bicarbonate Pak. J. Agri. Sci., Vol. 54(2), 443-450; 2017 ISSN (Print) 0552-9034, ISSN (Online) 2076-0906 DOI: 10.21162/PAKJAS/17.5014 http://www.pakjas.com.pk

Journal ArticleDOI
TL;DR: huge genetic diversity of mango is still waiting to be explored in Pakistan, therefore, unexplored germplasm can successfully be utilized in the breeding programs to develop new high yielding and premium quality cultivars.
Abstract: Mango (Mangifera indica L.) the choicest and abundantly consumed tropical and subtropical fruit, belongs to genus Mangifera and family Anacardiaceae having more than 40 species around the world (Subedi et al., 2009; Rajwana et al., 2011). Mango has been originated in the premises of Indian-Myanmar region and distributed to various phytogeographical areas of the world (Jha et al., 2010). Its cultivation in Pakistan dates back to the era of Mughal emperor ‘Akbar’ (Rajwana et al., 2011). Mango in Pakistan is cultivated between latitude 25-32° North East, including the districts of Sindh (Hyderabad, Mirpurkhas, Tando Allah Yar) and Punjab (Multan, Rahim Yar Khan, Bahawalpur, Lodhran, Muzzaffargarh, Khanewal, Vehri) province (Raza, 2011). Punjab province contributes about 67% to the total mango area having about 65% share in total fruit production in the country (MinFAL, 2010). Azad Jammu & Kashmir (AJK) and Northern Punjab (Gujrat, Sialkot) also have rich mango genetic diversity mostly in the form of wild seedling plantation which remained unexplored for decades. Despite the growing importance of Pakistani mango in the international market, its true potential has not yet been fully utilized and its production struggles with several constraints such as small number (10) of commercial varieties with low yield, narrow genetic base, disease and insect pest attack (Rajwana et al., 2011). Presently, huge genetic diversity of mango is still waiting to be explored in Pakistan. Therefore, unexplored germplasm can successfully be utilized in the breeding programs to develop new high yielding and premium quality cultivars (Mian and Nasir, 1989; Ahmad et al., 2007). Presently, development of new mango varieties with premium quality and high yield is the extreme demand of mango industry. However, its development through orthodox/conventional breeding is tedious, resource dependent and time consuming. On the other hand, selection of chance seedlings from existing indigenous germplasm is most suitable alternative (Begum et al., 2012). Mango trees showed extensive diversity due to out-breeding, alloploidy, continuous grafting and phenotypic differences arising under varied agro-climatic conditions in different mango growing regions (Ravishankar et al., 2000). In addition, mango being highly cross pollinated, open pollination between the cultivars has resulted in new genetic combinations that have not yet been documented. Geneticists and plant breeders are mainly concerned with diversity of germplasm at the molecular level; whereas, horticulturist/pomologist characterize and evaluate the Pak. J. Agri. Sci., Vol. 54(2), 287-297; 2017 ISSN (Print) 0552-9034, ISSN (Online) 2076-0906 DOI: 10.21162/PAKJAS/17.2945 http://www.pakjas.com.pk


Journal ArticleDOI
TL;DR: In this paper, the authors proposed a system dynamics approach to solve the problem of complex complexity in agricultural systems, which enables them to perform multi-scenario and multi-characteristic analyses, and to conduct relative comparisons among several competitive management strategies during the time.
Abstract: Agricultural development is the basis of human survival. However, critical resources for food production, including land and water are significantly under pressure of factors like population growth and economic development as well as ecological changes. Therefore, future farmers must produce a greater amount of agricultural products using fewer resources. As a result, an appropriate insight into the future developments of the agricultural sector is significantly important for both whole society and policy makers, reaching to which requires scientific and comprehensive models (Schneider et al., 2011). In recent years, agricultural systems have been widely studied and there are numerous researches which have discussed the interaction between different drivers and variables on global scales (Verburg et al., 2013; Schaldach et al., 2011). Some studies have revealed the implication and prospect of agriculture from an engineering and technical point of view, and some research has used economic assessments (Stoorvogel et al., 2004). Meanwhile, biophysical and geographic evaluations (Hu et al., 2014; Tittonell et al., 2009) are mainly based on different conditions of production and its consequences. In this regard, those studies which have merged the ecological, economical and technological aspects together are known as the integrated evaluations (Bouwman et al., 2006). With clear advantage on single-factor studies, these comprehensive studies are simultaneously able to measure the effects of a set of drivers and factors such as the economic development, population growth, environmental changes, technological progress and possible policy pathway (Schneider et al., 2011). In spite of the advantages of the integrated models, they incorporate some complexities. Senge (1994) introduces two types of complexity as below: (1) details, and (2) dynamics. Complexity of the details is associated with systems which have many components, while the complexity of the dynamics is related to those having effects which are separated by time and/or space (Zarghami and Akbariyeh, 2012). What is usually seen in the agricultural systems is the dynamic complexity which causes significant problems for agricultural management. This is because one cannot generally establish a relationship between their causes and effects which are removed during time or distance. To solve this type of complexity, the approach of system dynamics enables us to perform multi-scenario and multi-characteristic analyses, and to conduct relative comparisons among several competitive management strategies during the time (Sehlke and Jacobson, 2005). The SD method is based on Pak. J. Agri. Sci., Vol. 54(2), 457-466; 2017 ISSN (Print) 0552-9034, ISSN (Online) 2076-0906 DOI: 10.21162/PAKJAS/17.5476 http://www.pakjas.com.pk

Journal ArticleDOI
TL;DR: In this article, a pot experiment was conducted to evaluate the P-Zn interaction effects on wheat in calcareous saline-sodic soil, and the results showed that total number of tillers, plant height, straw dry weight and 1000grain weight was significantly (P <= 0.05) higher in saline sodic control closely followed by applied P at 75 mg kg(-1) soil + Zn at 5 mg kg-1)-soil (P75Zn5).
Abstract: The essentiality of phosphorus (P) as a macronutrient and that of zinc (Zn) as micronutrient for plants has been established long ago but their interactive effects on economic yield of crops are still controversial particularly in calcareous saline-sodic soils. Therefore, a pot experiment was conducted to evaluate the P-Zn interaction effects on wheat in saline-sodic soil. The treatments comprised of four levels of P (0, 25, 50 and 75 mg kg(-1) soil) and three levels of Zn (0, 5 and 10 mg kg(-1) soil) arranged in completely randomized design each with three replications. The results showed that total number of tillers, plant height, straw dry weight and 1000-grain weight was significantly (P <= 0.05) higher in saline-sodic control closely followed by applied P at 75 mg kg(-1) soil + Zn at 5 mg kg(-1) soil (P75Zn5). While maximum Zn concentration in wheat straw and grains was observed in P75Zn5. The maximum ammonium-bicarbonate-diethylene-triamine-penta-acetic acid (AB-DTPA) extractable P and Zn in post-experiment soil was recorded with P at 75 mg kg(-1) soil + Zn at 10 mg kg(-1) soil (P75Zn10). Thus, application of P at 75 mg kg(-1) soil along with Zn 5 mg kg(-1) soil was the appropriate combination of P and Zn for substantial increase in growth and yield of wheat in saline-sodic soil.

Journal ArticleDOI
TL;DR: One of the quick and simple methods for determining the species composition of fungal communities is based on sequencing particular regions of the fungal genome that has proven a reliable alternative to traditional methods.
Abstract: The fungus that causes rice blast is called Magnaporthe oryzae (formerly Magnaporthe grisea). It is an ascomycete because it produces sexual spores (ascospores) in structures called asci, and is classified in the newly erected family Magnaporthaceae. The asci are found within specialized structures called perithecia. The mycelium of M. oryzae is septate and the nuclei within the mycelium and spores of this fungus are haploid (TeBeest et al., 2007). Rice blast is an important disease economically and biologically but the most serious problem is in term of losses in temperate region and upland conditions. In china whitin last 30 years three outbreaks were occurred with average losses of 2.5 million tons in each period. In India, Japan and Indonesia, the highest occurrence of blast were more than 50%, 42.5% and 70% respectively (Wang and Valnet, 2009). In Malaysia it is reported that almost 1000 ha of rice plantation areas in Kedah state were suffered by rice blast disease annually. The number of cases was reduced in 2004, but increased again in 2009. In 2011, 30 ha of rice fields in Kedah state were affected by disease during the early planting stage which caused the losses of about RM 150000 (New Straits Times, 2012). It is believed that a large quantity of rice (10-30%) which can be enough for feeding 60 million people is blasted each year (Talbot, 2003). In fungi, the morphological species concept (MSC) is the most common technique of diagnosing species since morphological characteristics of individuals are easily detectable (Taylor et al., 2000). For distance conidia and conidiophore morphology are the main characteristics in phylum Ascomycota (Choi et al., 2013). Magnaporthe oryzae is mainly isolated on PDA. Initial cultures can then be subcultured onto PDA or alternative media. Guochang and Shuyuan (2001) reported oatmeal agar (OMA) induced good sporulation. The conidia vary in size and shape, the shape was described as pyriform to obclavate with round base and narrow apex, usually with 2 septate but rarely can have 1-3 septate. The size vary due to different growth condition from 19-23×7-9 μm (Ou, 1985). One of the quick and simple methods for determining the species composition of fungal communities is based on sequencing particular regions of the fungal genome that has proven a reliable alternative to traditional methods. Ribosomal genes and spacers regions within the fungal genome are good candidates for amplification via the polymerase chain reaction (PCR) since they are comprised of highly conserved tracts with heterogeneous regions in between. The conserved tracts are ideal for universal primer design that can allow for the amplification and sequencing of heterogeneous regions. Most molecular fungal species identification relies on the amplification and sequencing of Pak. J. Agri. Sci., Vol. 54(4), 785-792; 2017 ISSN (Print) 0552-9034, ISSN (Online) 2076-0906 DOI: 10.21162/PAKJAS/17.3786 http://www.pakjas.com.pk

Journal ArticleDOI
TL;DR: Yield and grain characteristics of maize plants grown in open-field conditions were evaluated after inoculation with Micosat F® on two different soils under dry and watered conditions; nevertheless, the NIRs indicated some physical differences among mycorrhized and not myCorrhized samples.
Abstract: Yield and grain characteristics of maize plants grown in open-field conditions were evaluated after inoculation with Micosat F® on two different soils under dry and watered conditions. The mycorrhizal frequency and intensity were higher in inoculated maize (87.8 vs 80.3% and 26.8 vs 17.5%, respectively). The abundance of arbuscules in the root system was also higher in inoculated plants (9.7 vs 5.8%). The treatment did not affect grain yield. Positive effect of Typic Eutrudept soil on grain yield was observed. The irrigation effect on grain yield was evident only under draught conditions. Chemical characteristics of grain did not change substantially according to the experimental treatments; nevertheless, the NIRs indicated some physical differences among mycorrhized and not mycorrhized samples.

Journal ArticleDOI
TL;DR: In this paper, the authors evaluated the efficacy of CO2 and N2 gases as a replacement for the current use of methyl bromide and phosphine for controlling developmental stages of C. cautella.
Abstract: Methyl bromide and phosphine have been used extensively for decades to control various stored product pests including the almond moth, Cadra cautella (Walker). However, these fumigants have serious issues. For example, methyl bromide has been declared an ozone depleting chemical and has been banned in developed countries since 2005 (UNEP, 1997). It is scheduled to be banned worldwide in 2015 in accordance with the Montreal Protocol (Schneider et al., 2003). Phosphine (PH3) fumigation efficacy is greater at low temperature of 15°C. Long exposure timings are required to achieve higher mortalities of khapra beetle, Trogoderma granarium Everts; red flour beetle, Tribolium castaneum (Herbst); rice weevil, Sitophilus oryzae (L.); maize weevil, Sitophilus zeamais Motschulsky, and lesser grain borer, Rhizopertha dominica (F.) (Hole et al., 1976). Efforts are being made to develop economical, safe, and environmentally friendly alternatives for the control of stored product insect pests. Chemicals such as carbonyl sulfide, sulfuryl fluoride, ozone, cyfluthrin, iodomethane, and nonchemical treatments including modified atmospheres, high pressure, heat/cold treatments, sanitation, radio frequency, long-wave energy and irradiation have been utilized (Desmarchelier et al., 1998; Johnson et al., 2000; Fields and White, 2002; Schneider et al., 2003; Aksoy et al., 2004; Cetinkaya et al., 2006). Several studies have demonstrated that applications of modified atmospheres (MA) and ozone are possible alternatives for methyl bromide against dried fruits pests including C. cautella (Soderstrom et al., 1984; Soderstrom et al., 1986; Navarro et al., 1993; Donahaye et al., 1994; Navarro et al., 1997; Donahaye et al., 1998; Navarro et al., 1998; Navarro et al., 2000, Husain et al., 2015; Husain et al., 2017). Application of MA, such as purging with CO2 or N2 are well-known, dependable and proven to be residue-free techniques for disinfestation of food storage products. Lethal effects of CO2 (89%) on different stages of S. zeamais and S. oryzae was proven as a good MA fumigant in a rice processing mill (Carvalho et al., 2012). Jay (1984, 1986) reported that CO2 applications at higher concentrations with increased temperatures of 38°C or above can effectively control stored product pests like R. dominica and S. zeamais within 24-48 h. Similarly, Navarro and Donahaye (1990) reported that higher insect mortality could be obtained in comparatively short exposure times at higher CO2 atmospheres than at lower O2 applications. The objective of the present study was to evaluate the efficacy of CO2 and N2 gases as a replacement for the current use of methyl bromide and phosphine for controlling developmental stages of C. cautella. Pak. J. Agri. Sci., Vol. 54(4), 731-736; 2017 ISSN (Print) 0552-9034, ISSN (Online) 2076-0906 DOI: 10.21162/PAKJAS/17.4085 http://www.pakjas.com.pk

Journal ArticleDOI
TL;DR: Citrus is an important fruit crop of the world with production of 122976 thousand tones and China ranks first in the list of citrus producing countries with an area of 2118 thousand hectare and production of 23977 thousand tones.
Abstract: Citrus is an important fruit crop of the world with production of 122976 thousand tones. China ranks first in the list of citrus producing countries with an area of 2118 thousand hectare and production of 23977 thousand tones, Brazil has the 2 position and USA is the 3 largest producer of the citrus in the world. Pakistan stands at the 13 position with an area of 198 thousand hectare and production 2150 thousand tones . Yield of citrus per acre in Pakistan is lower as compared to the majority of the rest of the world. Kinnow is an important citrus fruit of Pakistan. World’s best kinnow mandarin is produced in Pakistan. Pakistan is the world’s number one producer of kinnow mandarin (Memon, 2014). Candidatus Liberibacter, a Gram negative alphaproteobacterium is the causal organism of the huanglongbing (HLB) disease (Jagoueix et al., 1994; Li et al., 2012). In citrus plants, HLB bacterium multiplies in phloem. This bacterium was defined and named by Murray and Schleifer (1994) as Candidatus (uncultured bacteria) Liberibacter. The citrus HLB bacterium is about 2μm long and 0.2 μm in diameter (Bove, 2006). There are three isolate types of the bacterium: Candidatus Liberibacter asiaticus (Las), Candidatus Liberibacter africanus (Laf) (Da Graca, 1991) and Candidatus Liberibacter americanus (Lam) (Teixeira et al., 2005b). Diaphorina citri Kuwayama (Hemiptera: Sternorryncha: Lividae) and Trioza erytreae (Del Guercio) (Hemiptera: Sternorrynca: Triozidae) are the natural vectors of citrus greening disease pathogen (Aubert, 1987). Diaphorina citri Kuwayama (Hemiptera: Sternorryncha: Lividae) transmits both Candidatus Liberibacter asiaticus (Las) and Candidatus Liberibacter americanus (Lam) while Trioza erytreae (Del Guercio) (Hemiptera: Sternorrynca: Triozidae) transmits only Candidatus Liberibacter africanus (Laf). Liberibacter asiaticus is the most abundant species among HLB infected trees (Capoor et al., 1967; Jagoueix et al., 1994; Bove, 2006). The disease can also be transmitted through budding/grafting (Lin, 1956). In genus Diaphorina, there are also six other species found on citrus and their relatives but, of these six species only one species Diaphorina communis Mathur (Hemiptera: Sternorrynca: Liviidae) and one more psyllid: Cacopsylla citrisuga (Hemiptera: Psyllidae) also reported as Candidatus Liberibacter asiaticus vectors (Donovan et al., 2011; Cen et al., 2012). Among biotic stresses to citrus industry, HLB is a dangerous disease (Teixeira et al., 2005a; Hall et al., 2012). It has caused extreme loss (about 60 million) of citrus plants in African and Asian countries (Timmer et al., 2003). Huanglongbing was present in china in the 1800s. The report of the disease in China in 1800s was based on interviews with technicians and Pak. J. Agri. Sci., Vol. 54(1), 21-26; 2017 ISSN (Print) 0552-9034, ISSN (Online) 2076-0906 DOI: 10.21162/PAKJAS/17.4455 http://www.pakjas.com.pk