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Showing papers in "Current Science in 2005"


Journal Article
TL;DR: The genes governing the proline biosynthetic pathway, its degradation and regulation are summarized and an account on transgenics raised so far to engineer the overproduction of osmolyte proline is provided.
Abstract: Dramatic accumulation of proline due to increased synthesis and decreased degradation under a variety of stress conditions such as salt, drought and metal has been documented in many plants. Similarly, a decrease in the level of accumulated proline in the rehydrated plants is due to both down regulation of proline biosynthetic pathway enzymes and upregulation of proline degrading enzymes. But, the role of proline during plant development and the molecular basis of the effect of proline accumulation during stress and upon relief of stress are still largely obscure. Here, we summarize the genes governing the proline biosynthetic pathway, its degradation and regulation. Sequentially, we provide an account on transgenics raised so far to engineer the overproduction of osmolyte proline. Also, the identification of specific cellular pathways involved in proline biosynthesis and metabolic changes occurring in transgenic plants developed for proline enhancements are discussed. Further, emphasis is also made on an untouched area of signal transduction of proline biosynthetic pathway.

1,265 citations


Journal Article
TL;DR: The necessity to use molecular biology techniques for identification and characterization of rumen microbes has been emphasized in this review and the microbial ecosystem is well studied for the rumen of domesticated animals, but it is poorly studied in buffalo and wild ruminants.
Abstract: The inhabitants of the rumen microbial eco-system, a complex consortium of different microbial groups living in symbiotic relationship with the host, act synergistically for the bioconversion of lignocellulosic feeds intovolatile fatty acids which serve as a source of energy for the animals. The constraints, imposed by the host and the feed consumed by the animal, under which these microbes have to function, have been discussed. The eco-system is specialized and buffered in a narrow range of pH, which helps the animal to maintain a very well stabilized eco-system which is not disturbed by the incoming microbial contaminants into the fermentation sac (rumen) through feed and water intake. The microbial ecosystem is well studied for the rumen of domesticated animals like cattle, sheep and goat, but it is poorly studied in buffalo and wild ruminants. The necessity to use molecular biology techniques for identification and characterization of rumen microbes has been emphasized in this review.

595 citations


Journal Article
TL;DR: Understanding of ROS-induced oxidative damages and their protection by antioxidative system, is the newly discovered role of ROS in signalling processes, mediating the acquisition of tolerance to both biotic and abiotic stresses.
Abstract: The oxidative burst, during which large quantities of reactive oxygen species (ROS) like superoxide, hydrogen peroxide, hydroxyl radicals, peroxy radicals, alkoxy rad icals, singlet oxygen, etc. are generated, is one of the earliest responses of plant cells under various abio tic and biotic stresses and natural course of senescence. In fact, reactions involving ROS are an inherent fe ature of plant cells and contribute to a process of oxidative deterioration that may lead ultimately to cell death. Sources of ROS include leakage of electrons from electron transport systems, decompartmentalization of iron which facilitates generation of highly reactive h ydroxyl radicals, and also various biological reactions. The imposition of both abiotic and biotic stresses causes overproduction of ROS, which ultimately imposes a secondary oxidative stress in plant cells. Degradation of membrane lipids, resulting in free fatty acids, initiates oxidative deterioration by providing a substrate for enzyme lipoxygenase, causing membrane lipid peroxidation. Since lipid peroxidation is known to produce alkoxy, peroxy radicals as well as singlet oxygen, these reactions in the membrane are a major source of ROS in plant cells. Regulatory mechanisms function both at gene and protein level to coordinate antioxidant responses. Superimposed upon our understanding of ROS-induced oxidative damages and their protection by antioxidative system, is the newly discovered role of ROS in signalling processes. ROS like H2O2 act as a signalling molecule, second messenger, mediating the acquisition of tolerance to both biotic and abiotic stresses. ROS as ubiquitous messengers of stress responses likely play a signalling role in various ada ptive processes. Plants can sense, transduce and translate ROS signal into appropriate cellular responses with the help of some redox-sensitive proteins. Hydrogen peroxide has been implicated as a key factor mediating programmed cell death. Plants exposed to abiotic stresses can produce a systemic signal, a component of which may be H 2O2 which sets up an acclimatary response in unstressed regions of plants. ROS is also found to communicate with other signal molecules and the pathways forming part of signa lling network that controls responses downstream of ROS.

496 citations


Journal Article
TL;DR: The paper presents availability and demands of water resources in India as well as describes the various issues and strategies for developing a holistic approach for sustainable development and management of the water resources of the country.
Abstract: 3 per year, respectively. With rapid growing population and improving living standards the pressure on our water resources is increasing and per capita availabi lity of water resources is reducing day by day. Due to spatial and temporal variability in pr ecipitation the country faces the problem of flood and drought syndrome. Over- exploitation of groundwater is leading to reduction of low flows in the rivers, declining of the groundwater resources, and salt water intrusion in aquifers of the coastal areas. Over canal-irrigation in some of the com- mand areas has resulted in waterlogging and salinity. The quality of surface and groundwater resources is also deteriorating because of increasing pollutant loads from point and non-point sources. The climate change is expected to affect precipitation and water availability. So far, the data collection, processing, storage and dis- semination have not received adequate attention. The efforts initiated under the Hydrology Project Phase-I and the development of the Decision Support System proposed under Hydrology Project Phase-II are ex- pected to bridge some of the gaps between the developed advanced technologies of water resources planning, de- signing and management and their field applications. The paper presents availability and demands of water resources in India as well as describes the various issues and strategies for developing a holistic approach for sustainable development and management of the water resources of the country. It also highlight s integration of the blue and green flows and concepts of virtual water transfer for sustainable management of the wa- ter resources for meeting the demands of the present, without compromising the needs of future generations. OF all the planet's renewable resources, water has a unique place. It is essential for sustaining all forms of life, food production, economic development, and for general well being. It is impossible to substitute for most of its uses, difficult to de -pollute, expensive to transport, and it is truly a unique gift to mankind from nature. W ater is also one of the most manageable of the natural r esources as it is capable of diversion, transport, storage, and recycling. All these properties impart to water its great utility for human beings. The surface water and groundwater resources of the country play a major role in agriculture, hydropower generation, livestock production, industrial activities, fo restry, fisheries, navigation, recreational activities, etc. Accor d- ing to National Water Policy 1 in the planning and operation

450 citations


Journal Article
TL;DR: It is quite telling that (based on data from the 1945– 2005 edition of WoS) the article of Bush gathered almost 90% of all its 712 citations in WoS between 1975 and 2005, peaking in 1999 with 45 citations in that year alone.
Abstract: IT may appear blasphemous to paraphrase the title of the classic article of Vannevar Bush but it may be a mitigating factor that it is done to pay tribute to another legendary scientist, Eugene Garfield. His ideas of citationbased searching, resource discovery and quantitative evaluation of publications serve as the basis for many of the most innovative and powerful online information services these days. Bush 60 years ago contemplated – among many other things – an information workstation, the Memex. A researcher would use it to annotate, organize, link, store, and retrieve microfilmed documents. He is acknowledged today as the forefather of the hypertext system, which in turn, is the backbone of the Internet. He outlined his thoughts in an essay published in the Atlantic Monthly. Maybe because of using a nonscientific outlet the paper was hardly quoted and cited in scholarly and professional journals for 30 years. Understandably, the Atlantic Monthly was not covered by the few, specialized abstracting and indexing databases of scientific literature. Such general interest magazines are not source journals in either the Web of Science (WoS), or Scopus databases. However, records for items which cite the ‘As We May Think’ article of Bush (also known as the ‘Memex’ paper) are listed with appropriate bibliographic information. Google Scholar (G-S) lists the records for the Memex paper and many of its citing papers. It is a rather confusing list with many dead links or otherwise dysfunctional links, and a hodge-podge of information related to Bush. It is quite telling that (based on data from the 1945– 2005 edition of WoS) the article of Bush gathered almost 90% of all its 712 citations in WoS between 1975 and 2005, peaking in 1999 with 45 citations in that year alone. Undoubtedly, this proportion is likely to be distorted because far fewer source articles from far fewer journals were processed by the Institute for Scientific Information for 1945–1974 than for 1975–2005. Scopus identifies 267 papers citing the Bush article. The main reason for the discrepancy is that Scopus includes cited references only from 1995 onward, while WoS does so from 1945. Bush’s impatience with the limitations imposed by the traditional classification and indexing tools and practices of the time is palpable. It is worth to quote it as a reminder. Interestingly, he brings up the terms ‘web of trails’ and ‘association of thoughts’ which establishes the link between him and Garfield.

446 citations


Journal Article
TL;DR: This review describes some recent developments, particularly in India, to understand the relationship of soils and plants with the diversity of associated bacteria, and traces contributions of Indian scientists in isolating and defining the roles of plant growth promoting bacteria to evolve strategies for their better exploitation.
Abstract: The global necessity to increase agricultural production from a steadily decreasing and degrading land resource base has placed considerable strain on the fragile agro-ecosystems. Current strategies to maintain and improve agricultural productivity via high-input practices places considerable emphasis on 'fail-safe' techniques for each component of the production sequence with little consideration to the integration of these components in a holistic, systems approach. While the use of mineral fertilizers is considered the quickest and surest way of boosting crop production, their cost and other constraints deter farmers from using them in recommended quantities. In recent years, concepts of integrated plant nutrient management (IPNM) have been developed, which emphasize maintaining and increasing soil fertility by optimizing all possible sources (organic and inorganic) of plant nutrients required for crop growth and quality. This is done in an integrated manner appropriate to each cropping system and farming situation. Improvement in agricultural sustainability requires optimal use and management of soil fertility and soil physical properties, both of which rely on soil biological processes and soil biodiversity. An understanding of microbial diversity perspectives in agricultural context, is important and useful to arrive at measures that can act as indicators of soil quality and plant productivity. In this context, the long-lasting challenges in soil microbiology are development of effective methods to know the types of microorganisms present in soils, and to determine functions which the microbes perform in situ. This review describes some recent developments, particularly in India, to understand the relationship of soils and plants with the diversity of associated bacteria, and traces contributions of Indian scientists in isolating and defining the roles of plant growth promoting bacteria to evolve strategies for their better exploitation.

415 citations


Journal Article
TL;DR: The present discussion on density distribution of soil organic C in global wetlands could well be instrumental in formulating efficient strategies related to carbon sequestration and reduction of GHG emissions in wetland ecosystems.
Abstract: Wetlands are among the most important natural resources on earth They are the sources of cultural, economic and biological diversity With their wealth of stored carbon, wetlands provide a potential sink for atmospheric carbon, but if not managed properly could become sources of greenhouse gases (GHGs) such as carbon dioxide and methane Two important long-term uncertainties have initiated much debate in the scientific community These are global wetland area and the amount of carbon stored in it Compilation of relevant databases could be useful in setting up a long-term strategy for wetland conservation It has been difficult to estimate the net carbon sequestration potential of a wetland, because the rate of decomposition of organic matter and the abundance of methanogenic micro-organisms and fluxes from the sediment are extremely complex, and there are often gaps in relevant scientific knowledge The present discussion on density distribution of soil organic C in global wetlands could well be instrumental in formulating efficient strategies related to carbon sequestration and reduction of GHG emissions in wetland ecosystems Effective assessment of wetlands will only take place when the available information becomes accessible and usable for all stakeholders

414 citations


Journal Article
TL;DR: In this article, a set of specific specific PLFAs, viz. trans/cis ratio of monounsaturated fatty acids (16 : 1ω7, 18: 1ω 7), cyclopropyl (cy17:0 and cy19:0) fatty acids, and fungal PLFA (18:2w6) were able to distinguish the stressed environmental conditions such as heavy metal addition, tillage, organic compound toxicity, starvation and increased soil temperature.
Abstract: The key driving factor for sustainable agriculture is soil ecosystem, where pivotal services are provided by the soil biota, 'the biological engine of the earth', which can act as early warning signals of ecosystem health, and can be of use in environmental diagnosis. Phospholipid fatty acid (PLFA) profiles offer sensitive reproducible measurements for characterizing the numerically dominant portion of soil microbial communities without cultivating the organisms. The technique gives estimates of both microbial community composition and biomass size, and results represent in situ conditions in the soil. PLFA analysis has been used to detect various environmental stresses in the soil and was found to be more discriminatory than other methods. A set of certain specific PLFAs, viz. trans/cis ratio of monounsaturated fatty acids (16 : 1ω7, 18: 1ω7), cyclopropyl (cy17:0 and cy19:0) fatty acids, and fungal PLFA (18:2w6) were able to distinguish the stressed environmental conditions such as heavy metal addition, tillage, organic compound toxicity, starvation and increased soil temperature. This set of PLFA needs further testing and validation in the wide spectrum of environmental stressed conditions under diverse ecosystems, before its implication as bioindicators of environment monitoring and assessment at the global scale.

360 citations


Journal Article
TL;DR: This review is intended to focus on the biodiversity of cyanobacteria in various environments, recent application and new developments that are diversifying the directions for commercial exploitation.
Abstract: Cyanobacteria (also known as blue-green algae) are a group of extraordinarily diverse Gram-negative prokaryotes that originated 3.5 billion years ago. Their diversity ranges from unicellular to multicellular, coccoid to branched filaments, nearly colourless to intensely pigmented, autotrophic to heterotrophic, psychrophilic to thermophilic, acidophilic to alkylophilic, planktonic to barophilic, freshwater to marine including hypersaline (salt pans). They are found both free living and as endosymbionts. They are considered to be one of the potential organisms which can be useful to mankind in various ways. A number of important advances have occurred in cyanobacterial biotechnology in the recent years. World wide attention is drawn towards cyanobacteria for their possible use in mariculture, food, feed, fuel, fertilizer, colourant, production of various secondary metabolites including vitamins, toxins, enzymes, pharmaceuticals, pharmacological probes and pollution abatement. Only a few cyanobacterial strains (including Spirulina) have been well-characterized or exploited commercially. Basic research is needed to identify new cyanobacterial strains of high value products, strain improvement using molecular tools for rapid growth rate, ability to withstand varied environmental conditions and enhancement of synthesis of high value products. This review is intended to focus on the biodiversity of cyanobacteria in various environments, recent application and new developments that are diversifying the directions for commercial exploitation.

351 citations


Journal Article
TL;DR: Findings on EPS and their significance in biogeochemical processes are focused on microorganisms grow in free planktonic statediscussed with respect to their role in marine microbial ecology, marine food-web and other areas of future research.
Abstract: Microbial extracellular polymeric substances (EPS) are widely distributed in marine environments and are found in free dissolved form, colloids, discreet particles like TEP and/or associated with particulate matter, including cell aggregates, detritus, biofilms, microbial mats, etc. The chemical composition of EPS is influenced by various factors, including nutrients, temperature, pH, physiology and age of the culture. Microbial EPS perform various functions, and are nvolved in diverse marinei processes. The unique gelling properties of icrobial mEPS are considered important in the transport and trans-formation of organic matter, complexation of dissolved metals and biogeochemical cycling of elements. EPS are rich in organic carbon and therefore are an important source of carbon for different organisms in the food chain. The production of dissolved EPS during the bacterial growth, production of particulate rganic ocarbon from the dissolved EPS and enzymatic breakdown and conversion of particulate EPS into dissolved rganic omatter within the microbial loop, form an mportant ialternate route of organic carbon cycling in the arine mtrophic web. In this article, ecent findings on EPSr and their significance in biogeochemical processes areMicroorganisms grow in free planktonic statediscussed with respect to their role in marine microbial ecology, marine food-web and other areas of future research.

263 citations


Journal Article
TL;DR: In this paper, a conceptual domino-listric model of Kutch rift is presented, based on structural and detailed depth-wise analysis of aftershock data, and an attempt is made here to explain the dynamics of the earthquake generation in the Kutch basin.
Abstract: The Kutch basin is a western margin pericratonic rift basin of India. Nagar Parkar uplift in the north and Kathiawar uplift (Saurashtra horst) in the south respectively along Nagar Parkar and North Kathiawar faults delimit the E-W rift. The Kutch rift was initiated during the Late Triassic break up of the Gondwanaland by the reactivation of primordial faults in the Precambrian Delhi fold belt. The rifting was aborted during Late Cretaceous pre-collision stage of the Indian plate. During post-collision compressive regime of the Indian plate, the Kutch rift basin became a shear zone with strike-slip movements along sub-parallel rift faults. The Kutch Mainland Fault along the rift axis became the active principal fault. Presently, this right lateral strike-slip fault is overstepped by the South Wagad Fault in the eastern part of the basin. The overstep zone between the two wrench faults is a convergent transfer zone undergoing transpressional stress in the strained eastern part of the basin. The epicenters of two big earthquakes as well as the aftershock hypocenters of Bhuj earthquake are located within this zone. The study of the intrusive rocks, rift geometry and seismic tomography indicates presence of a large ultramafic body in the lower crust. An overview of the structural and tectonic evolution of the basin is discussed in the context of earthquakes. Based on structural and detailed depth-wise analysis of aftershock data, a conceptual domino-listric model of Kutch rift is presented here. On the basis of this model, an attempt is made here to explain the dynamics of the earthquake generation in the Kutch basin.

Journal Article
TL;DR: The ability of a plant to grow and yield well under zinc deficiency is attributed mainly to the effi ciency of acquisition of Zn under conditions of low soil, rather than to its utilization or re-translocation within a plant as discussed by the authors.
Abstract: One of the widest ranging abiotic stresses in world agriculture arises from low zinc (Zn) availability in calcareous soils, particularly in cereals. Cereal species greatly differ in their zinc effici ency (ZE), defined in this article as the ability of a plant to grow and yield well under Zn deficiency. ZE has been attributed mainly to the effi - ciency of acquisition of Zn under conditions of low soil Zn availability rather than to its utilization or (re)-translocation within a plant. A higher Zn acquisition efficiency, further, may be due to either or all of the following: an efficient ionic Zn uptake system, better root architecture, i.e. long and fine roots with architecture favouring exploitation of Zn from larger soil volume, higher synthesis and release of Zn-mobilizing phytosiderophore by the roots and uptake of Zn-phytosiderophore complex. Seed Zn content has also been suggested to affect ZE. This article attempts to examine critically the scanty and scattered reports available on the status of Zn defi ciency globally; morphological, biochemical and physiological basis of regulation of ZE in cereals and approaches to improve ZE in terms of grain productivity and grain Zn vis-a-vis its bioavailability under conditions of poor Zn availability. A causal relationship between important Zn-containing enzymes, viz. carbonic anhydrase (CA), Cu/Zn-superoxide dismutase (SOD) activities and ZE is reported in wheat and other cereal species. Enhanced production and release of Fe-mobilizing phytometallophores known as phytosiderophores (PS), is another mech anism relevant for cereal species in adaptation to zinc deficiency.

Journal Article
TL;DR: Study of different medicinally valued seeds of Nelumbo nucifera, Embelia ribes, Eugenia jambolana and leaves of Artocarpus heterophyllus showed Cr, K, Ca, Cu, Zn and Mn to be sufficient in seeds that have good nutritive value and are quite rich in carb ohydrates accompanied by enough protein, but are low in fat.
Abstract: Study of different medicinally valued seeds of Nelumbo nucifera, Embelia ribes, Eugenia jambolana and leaves of Artocarpus heterophyllus showed Cr, K, Ca, Cu, Zn and Mn to be sufficient in seeds of N. nucifera which also have good nutritive value and are quite rich in carb ohydrates accompanied by enough protein, but are low in fat. E. ribes seeds have even a higher nutritive value with high carbohydrate, enough mineral elements but low protein. Rich in Mg and moderate in protein, the E. jambolana seeds have a moderate nutritive value. A. heterophyllus leaves are not rich in desired mineral elements except Na, and have a low nutrition value. However, on a dry matter basis they too have a high nutritive value and are used as fodder for livestock.

Journal Article
TL;DR: The choice of parental background appeared to be crucial for sustainable expression of the crylAc transgene and the implications of variability in CrylAc expression and the seasonal decline on bollworm management are discussed.
Abstract: The quantitative levels of CrylAc and the seasonal decline in expression differed significantly among the eight commercial Bollgard hybrids tested. The CrylAc expression was found to be variable among the hybrids and alsobetween different plant parts. The leaves of Bt-cotton plants were found to have the highest levels of CrylAc expression followed by squares, bolls and flowers. The toxin expression in the boll-rind, square bud and ovary of flowers was clearly inadequate to confer full protection to the fruiting parts. Increasing levels of Helicoverpa armigera survival were correlated with the toxin levels decreasing below 1.8 μg/g in the plant parts. Genotype-independent seasonal decline of the CrylAc toxin levels was observed in all the hybrids. CrylAc expression decreased consistently as the plant aged. The decline in CrylAc was more rapid in some hybrids compared to others. The choice of parental background appeared to be crucial for sustainable expression of the crylAc transgene. The implications of variability in CrylAc expression and the seasonal decline on bollworm management are discussed.

Journal Article
TL;DR: In this paper, the results obtained by both these methods to evaluate the fracture process in the rock are compared and discussed, and a new approach is computed from AE amplitude distribution data, which involves filtering of high and low amplitude AE hits in a selective manner.
Abstract: Acoustic emissions (AE) produced during the compressive fracture of a brittle rock have been subjected to detailed analysis using an advanced software for the computation of b-value as well as improved b-value. Conventionally, the b-value of AE is calculated using the Gutenberg-Richter relationship, which is widely used in seismology. Determination of improved b-value is a new approach, which is computed from AE amplitude distribution data. It involves filtering of high and low amplitude AE hits (or events) in a selective manner. The results obtained by both these methods to evaluate the fracture process in the rock are compared and discussed.

Journal Article
TL;DR: conceptual issues related to the modelling of this component ('dark energy'), which is driving an accelerated expansion of the universe, are reviewed with special emphasis on the cosmological constant as the possible choice for the dark energy.
Abstract: Recent cosmological observations suggest that nearly seventy per cent of the energy density in the universe is unclustered and has negative pressure. Several conceptual issues related to the modelling of this component ('dark energy'), which is driving an accelerated expansion of the universe, are reviewed with special emphasis on the cosmological constant as the possible choice for the dark energy.

Journal Article
TL;DR: The enzymes of these microbes, which function in extreme environments (extremozymes), have several biotechnological applications, and Antibiotics, compatible solutes and other compounds obtainable from these microbes are also finding a variety of uses.
Abstract: A variety of microbes inhabit extreme environments. Extreme is a relative term, which is viewed compared to what is normal for human beings. Extreme environments include high temperature, pH, pressure, salt concentration,and low temperature, pH, nutrient concentration and water availability, and also conditions having high levels of radiation, harmful heavy metals and toxic compounds (organic solvents). Culture-dependent and culture-independent (molecular) methods have been employed for understanding the diversity of microbes in these environments. Extensive global research efforts have revealed the novel diversity of extremophilic microbes. These organisms have evolved several structural and chemical adaptations, which allow them to survive and grow in extreme environments. The enzymes of these microbes, which function in extreme environments (extremozymes), have several biotechnological applications. Antibiotics, compatible solutes and other compounds obtainable from these microbes are also finding a variety of uses.

Journal Article
TL;DR: In 2002, there was an unprecedented deficit of 49% in the all -India average rainfall in July, while the rainfall was close to the average during all the other months, and during droughts, rainfall over the vast majority of the subdivisions is deficit.
Abstract: 1–3 of 2002, with the all-India summer monsoon (June–September) rainfall (ISMR) being 19% less than the long-term average, led to considerable co ncern in the meteorological community since none of the pr edictions had suggested a large deficit in the ISMR. This was irrespective of whether the predictions were based on empir ical models used in the country for generating oper ational/ experimental forecasts, or generated in the different ce ntres in the world using the atmospheric general circulation mo dels 1 . Fortunately, the unanticipated failure of the Indian mo nsoon in the summer of 2002, was followed by the summer monsoon of 2003 for which the ISMR was 2% more than the average 4 . However, the relief was short-lived since the summer monsoon of 2004 has again been a drought (defined as a summer monsoon season for which the deficit in ISMR is larger than 10% of the long-term average), with the ISMR being 87% of the average. As in 2002, neither the forecast of the India Meteorological Depar tment (IMD) for the ISMR nor the predictions from the international ce ntres using atmospheric general circulation models (GCMs), suggested that there would be a drought. Clearly, it is far more important to generate accurate predictions of droughts/ excess rainfall seasons than of flu ctuations within 10% of the average. The variation of the summer monsoon rainfall from year to year is not coherent over the Indian region. Ge nerally, while some regions experience above-average rainfall, others suffer from deficit. Thus the anomalies (difference from the long-term average) of the summer monsoon rainfall are positive over some of the meteorological subdivisions and negative for others, particularly in the so -called normal years (i.e. with the magnitude of the ISMR anomaly <10% of the average). During droughts, rainfall over the vast majority of the subdivisions is deficit. This is illu strated in Figure 1 in which anomalies of the su mmer monsoon rainfall for the meteorological subdivisions (e xpressed as a percentage of the long-term average) for the droughts of 2002 and 2004 and the 2003 normal monsoon season are shown. The variation of the all -India rainfall is also generally not coherent within the monsoon season. Thus, in 2002 there was an unprecedented deficit of 49% in the all -India average rainfall in July, while the rainfall was close to the average during all the other months. In 2004, the all -India rainfall was close to the average in June and August, but well b elow the average in July and September (June: 100%, July: 81 %, August: 95% and September: 71%). This year, predictions were also made for the rainfall pa tterns of July and

Journal Article
TL;DR: Fungi are not only beautiful but play a significant role in the daily life of human beings besides their utilization in industry, agriculture, medicine, food industry, textiles, bioremediation, natural cycling, as biofertilizers and many other ways.
Abstract: The variety and galaxy of fungi and their natural beauty occupy prime place in the biological world and India has been the cradle for such fungi Only a fraction of total fungal wealth has been subjected to scientific scrutiny and mycologists have to unravel the unexplored and hidden wealth One third of fungal diversity of the globe exists in India Out of 15 million of fungi, only 50% are characterized until now Unfortunately, only around 5-10% of fungi can be cultured artificially Fungi are not only beautiful but play a significant role in the daily life of human beings besides their utilization in industry, agriculture, medicine, food industry, textiles, bioremediation, natural cycling, as biofertilizers and many other ways Fungal biotechnology has become an integral part of the human welfare

Journal Article
TL;DR: Considering the potential environmental benefits of organic production and its compatibility with integrated agricultural approaches to rural development, organic agriculture may be considered as a development vehicle for developing countries like India, in particular.
Abstract: Increasing consciousness about conservation of environment as well as health hazards associated with agrochemicals and consumers' preference to safe and hazard-free food are the major factors that lead to the growing interest in alternate forms of agriculture in the world. Organic agriculture is one among the broad spectrum of production methods that are supportive of the environment. The demand for organic food is steadily increasing both in the developed and developing countries with an annual average growth rate of 20-25%. Organic agriculture, without doubt, is one of the fastest-growing sectors of agricultural production. However, there are certain issues that should be clarified before we go for a large-scale conversion to organic agriculture. The most important issues are -Can organic farming produce enough food for everybody? Is it possible to meet the nutrient requirements of crops entirely from organic sources? Are there any significant environmental benefits that accrue from organic farming? Is the food produced by organic farming superior in quality? Is it economically feasible? In this article, we review these aspects of organic farming. In India, vast stretches of arable land, which are mainly rain-fed and found in the Northeastern region where negligible amount of fertilizers and pesticides are being used and have low productivity, could be exploited as potential areas for organic agriculture. Considering the potential environmental benefits of organic production and its compatibility with integrated agricultural approaches to rural development, organic agriculture may be considered as a development vehicle for developing countries like India, in particular.

Journal Article
TL;DR: The homegardens were found to be complex with plant diversity conserved through their use, and the role of the rural people in the management and preservation of biodiversity in their traditional home-gardening systems was examined.
Abstract: Homegardens are traditiona l agroforestry systems with complex structure and multiple functions. To understand the system, the socio -economic and biophysical aspects of homegardens in Dorgakona village, Barak Valley, North East India were studied. Since homegardens are also important sites for in situ on-farm conservation, the role of the rural people in the management and preservation of biodiversity in their traditional home-gardening systems was examined. The homegarden size falls within the range of 0.02 –1.20 ha with an average of 0.30 ha. The total number of species encountered in the homegardens was 122, with fruits as the dominant use -component. The homegardens are the sites of co n-servation of a large diversity of plants both wild and domesticated, because of their uses to the households. Thus the homegardens were found to be complex sy s-tems with plant diversity conserved through their use. H

Journal Article
TL;DR: This is the first study demonstrating that the cleavage reaction is also enzyme-catalyzed in addition to the enzymatic kinase activity of multifunctional NdK, and demonstrates a molecular mechanism that could be the basis for assessing in situ DNA damage by secretory mNdK.
Abstract: The reason for secretion of nucleoside diphosphate kinase (NdK), an enzyme involved in maintaining the cellular pool of nucleoside triphosphates in both prokaryotes and eukaryotes, by Mycobacterium tuberculosis is intriguing. We recently observed that NdK from M.tuberculosis (mNdK) localizes within nuclei of HeLa and COS-1 cells and also nicks chromosomalDNAin situ (A. K. Saini, K. Maithal, P. Chand, S. Chowdhury, R. Vohra, A. Goyal, G. P. Dubey, P. Chopra, R. Chandra, A. K. Tyagi, Y. Singh and V. Tandon (2004) J. Biol. Chem., 279, 50142–50149). In the current study, using a molecular beacon approach, we demonstrate that the mNdK catalyzes the cleavage of single strand DNA. It displays Michaelis–Menten kinetics with a kcat/KM of 9.65 (–0.88) · 106 M�1 s�1. High affinity (Kd � KM of �66 nM) and sequence-specific binding to the sense strand of the nuclease hypersensitive region in the c-myc promoter was observed. This is the first study demonstrating that the cleavage reaction is also enzyme-catalyzed in addition to the enzymatic kinase activity of multifunctional NdK. Using our approach, we demonstrate that GDP competitively inhibits the nuclease activity with a KI of �1.9 mM. Recent evidence implicates mNdK as a potent virulence factor in tuberculosis owing to its DNase-like activity. In this context, our results demonstrate a molecular mechanism that could be the basis for assessing in situ DNA damage by secretory mNdK.

Journal Article
TL;DR: In this article, a measure of the convergence rate between India and Tibet for the past five centuries has been used to estimate the magnitudes of Himalayan earthquakes since 1500, and the calculated rate ( 85 earthquakes, events that are unlikely to have escaped note in the historical written record.
Abstract: Re-evaluated estimates of the magnitudes of Himalayan earthquakes since 1500 (ref 1) permit a measure of the convergence rate between India and Tibet for the past five centuries Averaged over the entire Himalaya, the calculated rate ( 85 earthquakes, events that are unlikely to have escaped note in the historical written record The absence of repeated rupture anywhere in the Himalaya permits several explanations for the missing slip, ranging from the extreme view that large earthquakes are in our future, to less hazardous interpretations, related to flaws in the historical data on Himalayan earthquakes

Journal Article
TL;DR: There is a need for long-term quantitative documentation of tree phenological patterns in India through a phenological station network in diverse climatic/vegetational zones to enable better assessment of future climate change impact.
Abstract: The tropical dry forests constitute a mosaic composed of several phenological functional types adapted to seasonal drought in different ways Various functional types differ with respect to phenological timing and triggering factors, water relations, extent of deciduousness (∼ leaflessness), etc Duration of deciduousness in tropical trees (reflecting integrated effect of seasonal drought, tree characteristics and soil moisture conditions) is related to leafing patterns and resource use rates Vegetative and flowering phenology of trees in dry tropics is primarily affected by the periodicity of rainfall and soil water availability Occurrence of leaf-flushing as well as flowering during summer in majority of Indian tropical trees, when drought is severe, seems to be a unique adaptation to survive under strongly seasonal climate having a short growth promoting wet period and a long growth constraining dry period The key phenological themes that need research focus in the dry tropics are: duration of deciduousness, timing of vegetative bud break, leaf strategy, water relations, seasonal flowering types and asynchrony Analysis of functional types based on the duration of deciduousness and timing of bud break may enable better assessment of future climate change impact There is a need for long-term quantitative documentation of tree phenological patterns in India through a phenological station network in diverse climatic/vegetational zones

Journal Article
TL;DR: The spread of HIV in India has been di- verse, with much of India having a low rate of infection and the epidemic being most extreme in the southern states, with main focus on recent outcomes from natural sources as anti-HIV agents.
Abstract: Acquired immunodeficiency syndrome (AIDS), caused by human immunodeficiency virus (HIV), is an immuno- suppressive disease that results in life -threatening oppor- tunistic infections and malignancies. Despite continuous advances made in antiretrovira l therapy, AIDS has become the leading cause of death in Africa and fourth worldwide; the number of people with HIV is increasing at an alarming rate in India and Southeast Asia. Biodiversity of the plant kingdom has always provided a source of new drug candidates for almost all disease areas. The number of compounds exhibiting anti-HIV activity and isolated from natural sources is increasing steadily. Calanolide A, a coumarin isolated from Callophyllum lanigerum and two other natural product-derived molecules, DSB and 3-hydroxymethyl- 4-methyl DCK are phase II clinical candidates, with potential to come up as drugs for treatment of HIV i nfec- tion. Here, the natural products possessing anti-HIV activity have been discussed, with main focus on recent outcomes from natural sources as anti-HIV agents. ACQUIRED immunodeficiency syndrome (AIDS) is a clinical syndrome that is the result of infection with human i mmuno- deficiency virus (HIV), which causes profound i mmuno- suppression. It has been a serious, life -threatening health problem since the first case was identified in 1981 and is the most quickly spreading disease of the century. Since the epidemic began, more than 60 million people have been infected with the virus. HIV/AIDS is now the leading cause of death in Sub-Saharan Africa. Worldwide, it is the fourth biggest killer. According to recent reports of WHO and UNAIDS, at the end of 2004, an estimated 40 million people (37.2 million adults and 2.2 million children) globally were living with HIV, out of which about 22 million had died. The most affected is Sub-Saharan Africa, where 3.1 million adults and children became infected with HIV during the year 2004 and 2.3 million died in 2004. By the end of 2004, the total number of people living with HIV/ AIDS in the region has reached 25.4 million 1 . Around 1.2 million people in Asia acquired HIV in 2004, bringing the number of people living with HIV to an estimated 8.2 million. A further 540,000 people are estimated to have died of AIDS in 2004. The spread of HIV in India has been di- verse, with much of India having a low rate of infection and the epidemic being most extreme in the southern states. As of December 2004, 92% of all nationally reported AIDS cases has been found in 10 of the 28 states and 7 union territories. The greatest numbers were in Maharashtra and Gujarat in the west; Tamil Nadu and Andhra Pradesh in the south; and Manipur in the Northeast. In the southern states, the infections are mostly due to heterosexual contact, while infections are mainly found amongst injecting drug- users in Manipur and Nagaland. The maximum number of AIDS cases has been reported in Tamil Nadu (44,492) followed by Maharashtra (12,783) out of 96,978 AIDS cases in year 2004. A very high proportion of men and women infected with HIV virus are in their active reproductive ages and around half of the people who acquire HIV become infected before they turn 25. Of greater concern is the possibility of infected mothers transferring the disease to their babies

Journal Article
TL;DR: The use of 0.
Abstract: African rice Oryza glaberrima (2n = 24, AA) has many unique traits such as weed competitiveness, drought tolerance and the ability to grow under low input conditions. These traits have been recently combined with high yield of Oryza sativa to develop NERICA (NEw Rice for AfriCA). The new rice varieties are high-yielding, drought- and pest-resistant and are uniquely adapted to the growing conditions of West Africa. The major problems in combining useful traits of both cultivated Oryza species are sexual incompatibility and hybrid sterility. Reproductive barriers between the two species have been studied and genetic models based on sporogametophytic interactions proposed. The availability of a molecular linkage map of 0. glaberrima and molecular markers linked to sterility loci would aid in the introgression of desirable traits and elimination of sterility loci quickly. The use of 0. glaberrima in rice breeding is challenging, but promising. The genetic base of Asian rice 0. sativa can be widened for obtaining higher yields under adverse conditions and using non-transgenic approaches.

Journal Article
TL;DR: In India, Swaminathan and his team at the Indian Agricultural Research Institute, New Delhi initiated a major programme on mutagenesis in crop plants, broadly aimed at understanding the process of mutation and testing the efficacy of various mutagens.
Abstract: The discoveries during the late 1920s that the genetic material is amenable to changes excited geneticists who saw new opportunities for both basic and practical applications. During the 1950s, induced mutagenesis was widely pursued in the US, Europe, Japan and China. In India, Swaminathan and his team at the Indian Agricultural Research Institute, New Delhi initiated a major programme on mutagenesis in crop plants. These studies were broadly aimed at understanding the process of mutation, testing the efficacy of various mutagens, identifying optimum dose and the best method of treatment for different crop species; isolation of mutants of basic and applied value; elucidating the biological effects of radiation-treated media, seeds and vegetative propagules on the organisms consuming them.

Journal Article
TL;DR: The botany, pharmacology, biochemistry, market demand and trade of S. chirayita are reviewed and the need for research and development is highlighted.
Abstract: Swertia chirayita is a medicinal plant indigenous to temperate Himalaya. Its medicinal usage is reported in Indian pharmaceutical codex, the British and the American pharmacopoeias and in different traditional systems of medicines such as the Ayurveda, Unani and Siddha. The plant is used as a bitter tonic in treatment of fever and for curing various skin diseases. S. chirayita has an established domestic (Indian) and international market, which is increasing at a rate of 10% annually. The plant available in the market many a times is adulterated and substituted by close relatives of chirata. This article briefly reviews the botany, pharmacology, biochemistry, market demand and trade of the plant. This is an attempt to compile and document information on different aspects of S. chirayita and highlight the need for research and development.

Journal Article
TL;DR: Although the crop is self-incompatible in its breeding behaviour, the prevalence of two diverse accessions has facilitated seed production under Palampur conditions and triggered the production of plant material for its introduction amongst interested growers in large numbers.
Abstract: Two accessions of Stevia rebaudiana were successfully introduced in the experimental farm at the Institute of Himalayan Bioresource Technology, Palampur in 2000. Cultivation trial of these accessions was conducted during 2001-03. Overall crop performance was satisfactory for both the accessions and they were least affected by biotic and abiotic factors like high rainfall, frost, and infestation by insects and diseases. Quantitative differences were found in stevioside content of the two accessions, ranging between 6 and 8%. Accession 1 was superior in stevioside content and Accession 2 was superior in leaf biomass. Higher content of stevioside was found in the regenerated crop in January, during the second year of plant growth. With improved management practices, there is further scope for improvement in stevioside content. A laboratory-scale process was developed for the extraction of stevioside up to 63% purity. Although the crop is self-incompatible in its breeding behaviour, the prevalence of two diverse accessions has facilitated seed production under Palampur conditions. This has triggered the production of plant material for its introduction amongst interested growers in large numbers. The present communication outlines the growing pattern and stevioside yield from the North Indian region. Three cuts could be obtained during the two-year growing period of the crop.

Journal Article
TL;DR: An opportunity has arisen to use a pollen-specific gene, promoter and transgenic dihaploid (homozygous) lines, gene expression, proteomics, translational regulation and post-translational modification of genes to widen the scope of crop improvement.
Abstract: Androgenesis in flowering plants is a unique biological process. It provides an understanding of the biological basis of single -cell microspore embryogenesis to the production of a dihaploid plant. This system provides an u nparalleled opportunity to shorten the breeding cycle and fix agronomic traits in the homozygous state, such as recessive genes for disease resistance. The most desirable dihaploid variation in all the m ajor crops including rice, wheat, barley, maize, rape, cotton, sunflower, coffee, etc. has already been developed and uti lized in modern crop breeding. Many known and a few unknown factors are involved in such development. A few noteworthy factors are donor plants, genotypic variation, media composition, and handling of cu ltures, which may have a greater influence on the response of androgenesis. A further opportunity has arisen to use a pollen-specific gene, promoter and transgenic dihaploid (homozygous), gene expression, proteomics, translational regulation and post-translational modification of genes to widen the scope of crop improvement. The homozygous (isogenic) lines will provide unique genetic material for mapping populations for use in functional genomics and molecular breeding.