Food security is the main challenge in the developing world, particularly in the least developed countries. Orphan crops play a vital role in the food security and livelihood of resource-poor farmers ...and consumers in these countries. Like major crops, there are members of all food types—cereals, legumes, vegetables and root and tuber crops, that are considered to be orphan crops. Despite their huge importance for present and future agriculture, orphan crops have generally received little attention by the global scientific community. Due to this, they produce inferior yields in terms of both quantity and quality. The major bottlenecks affecting the productivity of these crops are little or no selection of improved genetic traits, extreme environmental conditions and unfavorable policy. However, some orphan crops have recently received the attention of the global and national scientific community where advanced research and development initiatives have been launched. These initiatives which implement a variety of genetic and genomic tools targeted major constraints affecting productivity and/or nutritional quality of orphan crops. In this paper, some of these initiatives are briefly described. Here, I provide key suggestions to relevant stakeholders regarding improvement of orphan crops. Concerted efforts are urgently needed to advance the research and development of both the major and orphan crops so that food security will be achieved and ultimately the livelihood of the population will be improved.
The increasing resilience to climate change in the agricultural sector report presents local-level priorities, informed by stakeholder input, to build agricultural resilience in both countries. The ...objectives of this study were threefold: (1) to improve the understanding of climate change projections and impacts on rural communities and livelihoods in selected regions of Jordan and Lebanon, specifically the Jordan River Valley and Lebanon's Bekaa Valley; (2) to engage local communities, farmers, local experts, and local and national government representatives in a participatory fashion in helping craft agricultural adaptation options to climate change; and (3) to develop local and regional climate change action plans that formulate recommendations for investment strategies and strategic interventions in local agricultural systems. The climate challenges confronting development in the Middle East are particularly stark. This region, and in particular its rural people, face what might be called a `triple threat` from climate change. First, the Middle East is already one of the driest and most water-scarce regions of the world (World Bank 2011) and faces severe challenges posed by high temperatures and limited water supplies. This report to assist Jordan and Lebanon in understanding the specific challenges and opportunities posed by climate change in the agricultural sector.
Cover crops play an increasingly important role in improving soil quality, reducing agricultural inputs and improving environmental sustainability. The main objectives of this critical global review ...and systematic analysis were to assess cover crop practices in the context of their impacts on nitrogen leaching, net greenhouse gas balances (NGHGB) and crop productivity. Only studies that investigated the impacts of cover crops and measured one or a combination of nitrogen leaching, soil organic carbon (SOC), nitrous oxide (N2O), grain yield and nitrogen in grain of primary crop, and had a control treatment were included in the analysis. Long‐term studies were uncommon, with most data coming from studies lasting 2–3 years. The literature search resulted in 106 studies carried out at 372 sites and covering different countries, climatic zones and management. Our analysis demonstrates that cover crops significantly (p < 0.001) decreased N leaching and significantly (p < 0.001) increased SOC sequestration without having significant (p > 0.05) effects on direct N2O emissions. Cover crops could mitigate the NGHGB by 2.06 ± 2.10 Mg CO2‐eq ha−1 year−1. One of the potential disadvantages of cover crops identified was the reduction in grain yield of the primary crop by ≈4%, compared to the control treatment. This drawback could be avoided by selecting mixed cover crops with a range of legumes and non‐legumes, which increased the yield by ≈13%. These advantages of cover crops justify their widespread adoption. However, management practices in relation to cover crops will need to be adapted to specific soil, management and regional climatic conditions.
Cover crops significantly (p < 0.001) decreased N leaching and significantly (p < 0.001) increased soil organic carbon sequestration without having significant (p > 0.05) effects on direct N2O emissions. Cover crops could mitigate net greenhouse gas balance by 2.06 ± 2.10 Mg CO2‐eq ha−1 year−1. One of the potential disadvantages of the cover crops identified was the reduction in grain yield of the primary crop by ≈4%, compared to the control treatment. This drawback could be avoided by selecting legume–non‐legume mixed cover crops. However, cover crop management need to be adapted to specific soil, management and regional climatic conditions.
This book, Underutilized Crops and Their Value Addition, is designed to provide in depth information of underutilized crops, their production, value addition and therapeutic uses in a balanced and ...comprehensive fashion to researchers, professionals and students. The book is well illustrated to help students, researchers and professionals to better understand the principles and concepts about the underutilized crops. The style of presentation throughout the book is easy to follow and comprehend. Professionals, researchers and students are constantly reminded of previous topics of relevance to current topics being discussed. This book is not only an excellent teaching tool, but it is also a suitable reference source for students and professionals.
Increasing global food demand, low grain reserves and climate change threaten the stability of food systems on national to global scales
. Policies to increase yields, irrigation and tolerance of ...crops to drought have been proposed as stability-enhancing solutions
. Here we evaluate a complementary possibility-that greater diversity of crops at the national level may increase the year-to-year stability of the total national harvest of all crops combined. We test this crop diversity-stability hypothesis using 5 decades of data on annual yields of 176 crop species in 91 nations. We find that greater effective diversity of crops at the national level is associated with increased temporal stability of total national harvest. Crop diversity has stabilizing effects that are similar in magnitude to the observed destabilizing effects of variability in precipitation. This greater stability reflects markedly lower frequencies of years with sharp harvest losses. Diversity effects remained robust after statistically controlling for irrigation, fertilization, precipitation, temperature and other variables, and are consistent with the variance-scaling characteristics of individual crops required by theory
for diversity to lead to stability. Ensuring stable food supplies is a challenge that will probably require multiple solutions. Our results suggest that increasing national effective crop diversity may be an additional way to address this challenge.
Several studies have shown that global crop production needs to double by 2050 to meet the projected demands from rising population, diet shifts, and increasing biofuels consumption. Boosting crop ...yields to meet these rising demands, rather than clearing more land for agriculture has been highlighted as a preferred solution to meet this goal. However, we first need to understand how crop yields are changing globally, and whether we are on track to double production by 2050. Using ∼2.5 million agricultural statistics, collected for ∼13,500 political units across the world, we track four key global crops-maize, rice, wheat, and soybean-that currently produce nearly two-thirds of global agricultural calories. We find that yields in these top four crops are increasing at 1.6%, 1.0%, 0.9%, and 1.3% per year, non-compounding rates, respectively, which is less than the 2.4% per year rate required to double global production by 2050. At these rates global production in these crops would increase by ∼67%, ∼42%, ∼38%, and ∼55%, respectively, which is far below what is needed to meet projected demands in 2050. We present detailed maps to identify where rates must be increased to boost crop production and meet rising demands.
Photorespiration is required in C
plants to metabolize toxic glycolate formed when ribulose-1,5-bisphosphate carboxylase-oxygenase oxygenates rather than carboxylates ribulose-1,5-bisphosphate. ...Depending on growing temperatures, photorespiration can reduce yields by 20 to 50% in C
crops. Inspired by earlier work, we installed into tobacco chloroplasts synthetic glycolate metabolic pathways that are thought to be more efficient than the native pathway. Flux through the synthetic pathways was maximized by inhibiting glycolate export from the chloroplast. The synthetic pathways tested improved photosynthetic quantum yield by 20%. Numerous homozygous transgenic lines increased biomass productivity by >40% in replicated field trials. These results show that engineering alternative glycolate metabolic pathways into crop chloroplasts while inhibiting glycolate export into the native pathway can drive increases in C
crop yield under agricultural field conditions.
The global increase in the proportion of land cultivated with pollinator‐dependent crops implies increased reliance on pollination services. Yet agricultural practices themselves can profoundly ...affect pollinator supply and pollination. Extensive monocultures are associated with a limited pollinator supply and reduced pollination, whereas agricultural diversification can enhance both. Therefore, areas where agricultural diversity has increased, or at least been maintained, may better sustain high and more stable productivity of pollinator‐dependent crops. Given that >80% of all crops depend, to varying extents, on insect pollination, a global increase in agricultural pollinator dependence over recent decades might have led to a concomitant increase in agricultural diversification. We evaluated whether an increase in the area of pollinator‐dependent crops has indeed been associated with an increase in agricultural diversity, measured here as crop diversity, at the global, regional, and country scales for the period 1961–2016. Globally, results show a relatively weak and decelerating rise in agricultural diversity over time that was largely decoupled from the strong and continually increasing trend in agricultural dependency on pollinators. At regional and country levels, there was no consistent relationship between temporal changes in pollinator dependence and crop diversification. Instead, our results show heterogeneous responses in which increasing pollinator dependence for some countries and regions has been associated with either an increase or a decrease in agricultural diversity. Particularly worrisome is a rapid expansion of pollinator‐dependent oilseed crops in several countries of the Americas and Asia that has resulted in a decrease in agricultural diversity. In these regions, reliance on pollinators is increasing, yet agricultural practices that undermine pollination services are expanding. Our analysis has thereby identified world regions of particular concern where environmentally damaging practices associated with large‐scale, industrial agriculture threaten key ecosystem services that underlie productivity, in addition to other benefits provided by biodiversity.
Increasing cultivation of pollinator‐dependent crops has placed a stress on global pollination capacity, which could have been ameliorated by a concomitant increase in agricultural diversification. However, this study reports a relatively weak and decelerating rise in agricultural diversity over time that was largely decoupled from the strong and continually increasing trend in agricultural dependency on pollinators. Particularly worrisome is a rapid expansion of pollinator‐dependent monocultures in several countries of the Americas and Asia that has resulted in a decrease in agricultural diversity. In these regions, reliance on pollinators is increasing, yet agricultural practices that undermine pollination services are expanding.
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