Technologies for Intensification of Production and Uses of Grain Legumes for Nutrition Security

Malnutrition resulting from intake of food poor in nutritional value, particularly lacking in micronutrients, has been recognized as a serious health problem in developing countries including India. Nutritional security is a priority for India. Crop diversification in agriculture contributes to balanced diet and nutritional security. Production intensification of nutrient-dense crops, contributes to their increased production, and consequently enhances their accessibility at affordable prices to meet nutritional security. Grain legumes produce nutrient-dense grains rich in proteins, vitamins, minerals and micronutrients essential for growth and development. However, cultivation of grain legumes is often neglected resulting in poor production in the country, and consequently poor access to legumes at affordable prices. Pigeonpea or red gram (Cajanus cajan L.), chickpea or bengal gram (Cicer arietinum L.) and groundnut (Arachis hypogaea L.), the three nutritious grain legumes are grown widely across the country and are major constituents of Indian diets. They are climate- resilient crops adapted to water-limiting conditions making them choice crops for cultivation in adverse conditions. Policy options for promoting cultivation and increased production of pigeon pea, chickpea and groundnut are needed. Technology options for intensification of their cultivation include improved cultivars of grain legumes with enhanced adaptation and nutritional properties, their processing, plugging post-harvest and storage losses, and development of alternative food products. The chapter discusses the contribution of agriculture to nutritional security and the need to diversify cultivation of crops to include nutrient-dense grain legumes, and intensification of their cultivation to achieve their enhanced production and productivity. The scope to develop bio-fortified grain legumes is also discussed. Some countries have successfully harnessed the potential of processed grain legumes for use as food supplements for children and elderly, as well as to prepare ready-to-use-therapeutic-food products to treat acute malnutrition

Genetic characterization of mango anthracnose pathogen Colletotrichum gloeosporioides Penz. by random amplified polymorphic DNA analysis

Twenty-five isolates of Colletotrichum gloeosporioides causing mango anthracnose were collected from different agroclimatic zones of India. The isolates were evaluated for their pathogenic variability on mango seedlings and genetic characterization using random amplified polymorphic DNA (RAPD molecular techniques). The random primers OPA-1, 3, 5, 9, 11, 15, 16 and 18 were used and the twenty five isolates were grouped into two. The amplified DNA fragments (amplicons) obtained was comparedby agarose gel electrophoresis. Isolate specific RAPD fingerprints were obtained. Out of eight primers in RAPD, OPA-1, 3 and 18 were able to produce reproducible banding pattern. Each of these primers generated a short spectrum of amplicons, located between 661 and 2291-bp markers, indicative of genetic polymorphism. Dendogram revealed more than 75% level of similarity. 4.36% polymorphism was also found in individual isolates that was not statistically significant (P > 0.05) among the sample, it also indicates that all the isolates tested had approximately same genetic identity. The data suggest that RAPD may be of value by virtue of its rapidity, efficiency and reproducibility in generating genetic fingerprints of C. gloeosporioides isolates

Abscisic acid induces heat tolerance in chickpea (Cicer arietinum L.) seedlings by facilitated accumulation of osmoprotectants

The gradual rise of global temperature is of major concern for growth and development of crops. Chickpea (Cicer arietinum L.) is a heat-sensitive crop and hence experiences damage at its vegetative and reproductive stages. Abscisic acid (ABA), a stress-related hormone, is reported to confer heat tolerance, but its mechanism is not fully known, especially whether it involves osmolytes (such as proline, glycine betaine and trehalose) in its action or not. Osmolytes too have a vital role in saving the plants from injurious effects of heat stress by multiple mechanisms. In the present study, we examined the interactive effects of ABA and osmolytes in chickpea plants grown hydroponically at varying temperatures of 30/25°C (control), 35/30, 40/35 and 45/40°C (as day/night (12 h/12 h)): (a) in the absence of ABA; (b) with ABA; and (c) in the presence of its biosynthetic inhibitor fluridone (FLU). The findings indicated severe growth inhibition at 45/40°C that was associated with drastic reduction in endogenous ABA and osmolytes compared to the unstressed plants suggesting a possible relationship between them. Exogenous application of ABA (2.5 μM) significantly mitigated the seedling growth at 40/35 and 45/40°C, while FLU application intensified the inhibition. The increase in growth by ABA at stressful temperature was associated with enhancement of endogenous levels of ABA and osmolytes, while this was suppressed by FLU. ABA-treated plants experienced much less oxidative damage measured as malondialdehyde and hydrogen peroxide contents. Exogenous application of proline, glycine betaine and trehalose (10 μM) also promoted the growth in heat-stressed plants and their action was not significantly affected with FLU application, suggesting that these osmolytes function downstream of ABA, mediating partially the protective effect of this hormon

Chickpea molecular breeding: new tools and concepts

Chickpea is a cool season grain legume of exceptionally high nutritive value and most versatile food use. It is mostly grown under rain fed conditions in arid and semi-arid areas around the world. Despite growing demand and high yield potential, chickpea yield is unstable and productivity is stagnant at unacceptably low levels. Major yield increases could be achieved by development and use of cultivars that resist/tolerate abiotic and biotic stresses. In recent years the wide use of early maturing cultivars that escape drought stress led to significant increases in chickpea productivity. In the Mediterranean region, yield could be increased by shifting the sowing date from spring to winter. However, this is hampered by the sensitivity of the crop to low temperatures and the fungal pathogen Ascochyta rabiei. Drought, pod borer (Helicoverpa spp.) and the fungus Fusarium oxysporum additionally reduce harvests there and in other parts of the world. Tolerance to rising salinity will be a future advantage in many regions. Therefore, chickpea breeding focuses on increasing yield by pyramiding genes for resistance/tolerance to the fungi, to pod borer, salinity, cold and drought into elite germplasm. Progress in breeding necessitates a better understanding of the genetics underlying these traits. Marker-assisted selection (MAS)would allowa better targeting of the desired genes. Genetic mapping in chickpea, for a long time hampered by the little variability in chickpea’s genome, is today facilitated by highly polymorphic, co-dominant microsatellite-based markers. Their application for the genetic mapping of traits led to inter-laboratory comparable maps. This paper reviews the current situation of chickpea genome mapping, tagging of genes for ascochyta blight, fusarium wilt resistance and other traits, and requirements for MAS. Conventional breeding strategies to tolerate/avoid drought and chilling effects at flowering time, essential for changing from spring to winter sowing, are described. Recent approaches and future prospects for functional genomics of chickpea are discussed

Effect of varying high temperatures during reproductive growth on reproductive function, oxidative stress and seed yield in chickpea genotypes differing in heat sensitivity

The mechanisms affecting the heat sensitivity of chickpea are largely unknown. Heat-tolerant (ICCV07110, ICCV92944) and heat-sensitive (ICC14183, ICC5912) chickpea genotypes were sown in February in the soil-filled pots. At the time of flowering, these were subjected to varying day/night temperatures of 30/20, 35/25, 40/30 and 45/35°C in the growth chambers (12 h light/12 h dark; light intensity, 250 μmol m−2 s−1, 80% relative humidity). The pollen viability, pollen germination, tube growth, pollen load and stigma receptivity decreased with increases in temperatures to 45/35°C. The heat-tolerant genotypes experienced significantly less damage to pollen and stigma function. Membrane integrity, chlorophyll content, photochemical efficiency and cellular oxidizing ability were inhibited by the increase in temperature, with greater impacts on the sensitive genotypes. Oxidative injury as lipid peroxidation and hydrogen peroxide content was significantly greater in sensitive genotypes at 40/30 and 45/35°C. Enzymatic and non-enzymatic antioxidants showed increased levels at 40/30°C, but decreased considerably at 45/35°C. Heat-tolerant genotypes possessed greater activity of ascorbate peroxidase and glutathione reductase, along with higher levels of ascorbate and reduced glutathione at 40/30 and 45/35°C. Biomass, pod set and yield were not affected significantly at 35/25°C, but began to decrease at 40/30°C and were lowest at 45/35°C. The sensitive genotypes were not able to set any pods at 45/35°C, whereas the tolerant genotypes produced only few fertile pods at this temperature. It was concluded that heat stress leads to loss of pollen as well as stigma function and induces oxidative stress in the leaves that cause failure of fertilization and damage to the leaves, respectively

Chefe (ICCV 92318) - a new kabuli chickpea variety for Ethiopia

Chefe (ICCV 92318) is a new kabuli chickpea cultivar developed from a 3-way cross, i.e. (ICCV 2 × Surutato) × ICC 7344, at ICRISAT, Patancheru, Andhra Pradesh, India, and released in 2004 primarily for its attractive and large (35 g/100 seeds) seeds (compared to 26 g/100 seeds in Arerti), and high level of resistance to Fusarium wil

Structural and functional analysis of rice genome

Rice is an excellent system for plant genomics as it represents a modest size genome of 430 Mb. It feeds more than half the population of the world. Draft sequences of the rice genome, derived by whole-genome shotgun approach at relatively low coverage (4-6 X), were published and the International Rice Genome Sequencing Project (IRGSP) declared high quality (>10 X), genetically anchored, phase 2 level sequence in 2002. In addition, phase 3 level finished sequence of chromosomes 1, 4 and 10 (out of 12 chromosomes of rice) has already been reported by scientists from IRGSP consortium. Various estimates of genes in rice place the number at >50,000. Already, over 28,000 full-length cDNAs have been sequenced, most of which map to genetically anchored genome sequence. Such information is very useful in revealing novel features of macroand micro-level synteny of rice genome with other cereals. Microarray analysis is unraveling the identity of rice genes expressing in temporal and spatial manner and should help target candidate genes useful for improving traits of agronomic importance. Simultaneously, functional analysis of rice genome has been initiated by marker-based characterization of useful genes and employing functional knock-outs created by mutation or gene tagging. Integration of this enormous information is expected to catalyze tremendous activity on basic and applied aspects of rice genomics

How rising temperatures would be detrimental for cool and warm-season food legumes

Rising temperatures are a major concern for the productivity of food legumes, grown in winter as well as summer-season, especially in tropical and sub-tropical regions. Our studies have indicated marked damage to the reproductive stage, resulting in reduction in pod set and seed yield of chickpea, lentil (cool-season legumes) and mungbean (warm-season legume) under high temperatures. Studies done in controlled and outdoor environments (late sowing) revealed that temperatures >35/20°C (as day and night) were highly detrimental for winter-season legumes; while >38/25°C markedly affected the summer-season legumes (mungbean). Urdbean, (a summer season legume), was found to be relatively more tolerant. The degree of damage varies depending upon the duration, timing and severity of stress. Among the reproductive components, pollen grains were more sensitive, became deformed and showed reduction in pollen viability, reduced germination and pollen tube growth. Stigma receptivity and ovule viability were also inhibited, which affected the pollen germination on stigma surface and restricted tube growth through style, and impaired fertilization to cause flower abortion. Assessment of the physiology of leaves, anthers and styles indicated decrease in sucrose production in all these organs due to inhibition of enzymes, which possibly affected the structural and functional aspects of the pollen grains and tube growth through style. Seed filling is another stage which becomes impaired as a result of inactivation of enzymes related to sucrose production, causing inhibition in sucrose translocation into seeds. Additionally, the composition of the seeds was adversely affected, resulting in small size and poor quality of seeds. The data related to these processes would be presented. Genetic variation for heat tolerance exists in our target legume crops, which needs further probing and use of heat tolerant germplasm in breeding programs. Screening for high temperature tolerance has led to identification of few heat-tolerant genotypes, which are able to maintain their gamete function at high temperature, unlike the sensitive genotypes. Future studies should focus on high throughput phenotyping techniques and/or physiological, biochemical or genetic markers that control the reproductive function. Information about the effects of heat stress on reproductive biology and seed filling events of chickpea, lentil and mungbean will be discussed