The origin of plant cell and tissue culture can be found in a treatise published during the mid-18th century, entitled La Physique des Arbes, that describes the formation of callus tissue following the for mation of a ring of cortex from elm trees. Over the next two centuries, the discovery of plant growth hormones, in particular auxins and cytokinins, and detailed analyses on the nutritional requirements of plants, led to the formulation of media that could maintain actively dividing cultures derived from gymnosperms, and both dicotyledon ous and monocotyledonous angiosperms. However, much of the prog ress and technological development in the in vitro propagation of plant cells, tissues, and organs has occurred during the last 25 years. Recently, plant tissue culture techniques have been used as basic tools in the rapidly expanding field of plant biotechnology for the development and clonal propagation of new and/or improved plant varieties. Plant tissue culture is used for the micropropagation of commercially valuable cultivars that include ornamentals, oil palm, Glycyrrhiza, Pyrethrum, pine, Eucalyptus, sugar cane, and potatoes. Cultured plant tissue is also used for the selection of cells and, ul timately, the regeneration of plants that are tolerant to physical stresses such as pathogens, drought, and temperature extremes, and to chemical stress agents such as salinity, herbicides, proteins, and pyrethrins. In addition, new plants have been produced by the fusion of protoplasts prepared from cultured cells of different species in cluding sunflower and french bean, tomato and potato, and various cultivars of Datura. Finally, bacterial vectors and various mechanical methods have been used to introduce foreign genes into cultured plant tissues. Genetic transformation can result in profound changes in the phenotype and/or biochemical profile of the regenerated trans genic plants that are not characteristic of the wild type. An impressive variety of technologies in tissue culture, genetic manipulation, and molecular biology have been developed for nu merous plant species. Many of these techniques, sometimes referred to as plant biotechnology, have been extensively summarized and compiled in a well-balanced collection of easy-to-follow protocols presented in three separate, but complimentary, volumes. Plant Cell, Tissue and Organ Culture consists of 22 chapters (with 86 figures) and 5 appendices. The chapters cover critical aspects of (a) the es sential requirements for the operation of a plant tissue culture lab oratory; (b) the basic procedures of micropropagation, regeneration, and somatic embryogenesis; (c) some specific applications of organ culture systems such as embryo rescue and culture, and anther and microspore culture for haploid and double haploid production; (d) elementary transformation technology; and (e) useful microtechnique and analytical protocols specifically adapted to cultured tissues and cells. The appendices provide a convenient summary of media for mulations and commercial suppliers for the materials described in the text.

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Plant Cell, Tissue and Organ Culture

Predators and scavengers are frequently persecuted for their negative effects on property, livestock and human life. Research has shown that these species play important regulatory roles in intact ecosystems including regulating herbivore and mesopredator populations that in turn affect floral, soil and hydrological systems. Yet predators and scavengers receive surprisingly little recognition for their benefits to humans in the landscapes they share. We review these benefits, highlighting the most recent studies that have documented their positive effects across a range of environments. Indeed, the benefits of predators and scavengers can be far reaching, affecting human health and well-being through disease mitigation, agricultural production and waste-disposal services. As many predators and scavengers are in a state of rapid decline, we argue that researchers must work in concert with the media, managers and policymakers to highlight benefits of these species and the need to ensure their long-term conservation. Furthermore, instead of assessing the costs of predators and scavengers only in economic terms, it is critical to recognize their beneficial contributions to human health and well-being. Given the ever-expanding human footprint, it is essential that we construct conservation solutions that allow a wide variety of species to persist in shared landscapes. Identifying, evaluating and communicating the benefits provided by species that are often considered problem animals is an important step for establishing tolerance in these shared spaces.

https://espace.library.uq.edu.au/view/UQ:718697/UQ718697_OA.pdf

The contribution of predators and scavengers to human well-being

Understanding household livelihood strategies is pivotal to minimize rural poverty in the least developed countries like Nepal. This study is an attempt to assess livelihood strategies pursued by rural households, investigate the most remunerative strategy, and identify the factors that influence a household’s choice of better strategies in rural Nepal. Primary data collected in 453 households from three villages of central Nepal are analyzed quantitatively within a sustainable livelihood framework. This study categorized households into five main livelihood strategy groups. The results showed that the majority (61%) of the households diversified their income to non-farm sources. Livelihood diversification to business/enterprise strategies adopted by 16% of the households is the most remunerative strategy followed by commercial farming that includes 13% of the sample and are more relevant to poverty reduction. Land holding, education, agriculture and skill training, access to credit, and proximity to the road and market center are the major influencing factors on the adoption of higher returning livelihood strategies. Stimulating poor households to follow market-oriented farm and non-farm activities by improving access to education, vocational training, rural credit, and rural infrastructures is momentous for reducing poverty in the rural areas of central Nepal.

https://www.mdpi.com/2071-1050/9/4/612/pdf

Household Livelihood Strategies and Implication for Poverty Reduction in Rural Areas of Central Nepal

We present a synthetic review and expert consultation that assesses the actual risks posed by arthropod pests in four major crops, identifies targets for integrated pest management (IPM) in terms of cultivated land needing pest control and gauges the implementation “readiness” of non-chemical alternatives. Our assessment focuses on the world’s primary target pests for neonicotinoid-based management: western corn rootworm (WCR, Diabrotica virgifera virgifera) in maize; wireworms (Agriotes spp.) in maize and winter wheat; bird cherry-oat aphid (Rhopalosiphum padi) in winter wheat; brown planthopper (BPH, Nilaparvata lugens) in rice; cotton aphid (Aphis gossypii) and silver-leaf whitefly (SLW, Bemisia tabaci) in cotton. First, we queried scientific literature databases and consulted experts from different countries in Europe, North America, and Asia about available IPM tools for each crop-pest system. Next, using an online survey, we quantitatively assessed the economic relevance of target pests by compiling country-level records of crop damage, yield impacts, extent of insecticide usage, and “readiness” status of various pest management alternatives (i.e., research, plot-scale validation, grower-uptake). Biological control received considerable scientific attention, while agronomic strategies (e.g., crop rotation), insurance schemes, decision support systems (DSS), and innovative pesticide application modes were listed as key alternatives. Our study identifies opportunities to advance applied research, IPM technology validation, and grower education to halt or drastically reduce our over-reliance on systemic insecticides globally.

/pdf/an-update-of-the-worldwide-integrated-assessment-wia-on-4cvdma7w2p.pdf

An update of the Worldwide Integrated Assessment (WIA) on systemic pesticides. Part 4: Alternatives in major cropping systems

Revealing the role of livelihood assets in livelihood strategies: Towards enhancing conservation and livelihood development in the Hara Biosphere Reserve, Iran

Frogs as potential biological control agents in the rice fields of Chitwan, Nepal

Gender mainstreaming is a key for achieving inclusive economic growth, poverty reduction and equitable development. A gender disaggregated analysis of changing livelihood activities is, therefore, crucial for devising gender-sensitive policies and programs. This paper presents a gender disaggregated analysis to assess trend and influencing factors of switching livelihood to higher returning activities at the intra-household level in three villages in rural areas of central Nepal. The result showed that both men and women have changed their livelihood activities from subsistence to cash-earning activities in the last decade. However, the livelihood activities of men have changed considerably compared to women. Men are primarily attracted to out-migration and non-farm wage-based jobs whereas women to market-oriented commercial farming and rural enterprises. Individual as well as location-specific characteristics influence behavior switching to higher returning activities irrespective of gender, while the ethnicity of a household influences only women. Building human and financial capital through education and training along with strengthening access to credit and increasing connectivity through rural road and market centers would be pivotal for encouraging rural men and women to change traditional subsistence activities to higher returning undertakings, leading to equitable livelihood improvement in rural Nepal.

A Gender Analysis of Changing Livelihood Activities in the Rural Areas of Central Nepal

Effect of conservation agriculture on maize-based farming system in the mid-hills of Nepal

High land fragmentation and accelerated rate of conversion of agriculture land are major challenges for food security of Nepal. Realizing ineffectiveness of previous efforts to manage these problems, government of Nepal has adopted land use policy 2012. The paper reviews the effects of previous land management policies on land fragmentation and conversion of agriculture land, and analyzes land use policy 2012 with respect to these problems. Analysis suggested that land fragmentation and high rate of agriculture land conversion could partly be attributed to failures of previous land management policies that were adopted for land re-distribution. Land use policy 2012 has proposed classical regulation tools for controlling land fragmentation and conversion of agriculture land such as land pooling, land classification, zoning and tax/ incentive based discrimination. Considering long history of non-regulated land use system in Nepal, the acceptability of the strong regulatory provisions could be the main constrain for successful implementation of the policy, thereby recoiling the effort to control land fragmentation and agriculture land conversion in Nepal.

https://mpra.ub.uni-muenchen.de/58880/1/MPRA_paper_58880.pdf

Bikash Paudel

Papers

Household Livelihood Strategies and Implication for Poverty Reduction in Rural Areas of Central Nepal

Frogs as potential biological control agents in the rice fields of Chitwan, Nepal

A Gender Analysis of Changing Livelihood Activities in the Rural Areas of Central Nepal

Effect of conservation agriculture on maize-based farming system in the mid-hills of Nepal

Fragmentation and conversion of agriculture land in Nepal and Land Use Policy 2012