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Finger millet [Eleusine coracana (L.) Gaertn.] is an important and nutritious cereal cultivated largely in the tropics of Africa and Asia. It is adversely affected by intermittent droughts, and a trait-based selection for drought tolerance is expected to enhance yield stability. The current work has segregated the shoot biomass as total water use (T) and transpiration efficiency (TE) and assessed the importance of these components and their association with drought tolerance. A major part of the minicore collection of finger millet germplasm (n = 69) was evaluated in mini-lysimeters for the variation in T and TE under both terminal drought-stress (DS) and well-watered (WW) environments. Contribution of T to shoot biomass under drought was minor but that of TE was large and positive. Both T and TE positively influenced the shoot biomass production. Total water use explained the shoot biomass variation more when WW, whereas TE explained more variation under DS. Under DS, the minicore germplasm accessions varied in shoot biomass by 0.5-fold, T by 0.16- to 0.36-fold, and the TE by twofold. Categorization of the finger millet germplasm for TE differentiated accessions, into high and low groups, each with 11 accessions. No distinct or useful race or subrace-specific variation was found for T, TE, or the total shoot biomass productivity among the four races of finger millet. Selection and incorporation of both T and TE would enhance the efficient use of water and yield stability. [ABSTRACT FROM AUTHOR]

Peanut (Arachis hypogaea L.) is extensively grown by resource-poor farmers in the semiarid tropics where many abiotic and biotic stresses limit the crop's productivity and seed quality. Peanut cultivars with enhanced host-plant resistance, adaptation to abiotic stress, input-use efficiency, and yield potential will maximize yield gains and minimize inputs to sustain production. The peanut mini core collection was evaluated for agronomic traits in multienvironment trials at Patancheru, India. The published information on 184 mini core accessions revealed 28 accessions resistant to abiotic stress, 30 resistant to biotic stress, and 18 that were agronomically desirable but susceptible to stresses, while 16 were seed nutrient dense. The mini core is part of the composite collection, which was previously genotyped using SSRs. The agronomic evaluation, stress response, and nutritional information together with genotyping data were used to identify genetically diverse germplasm with agronomically beneficial traits: ICG 12625 (resistance to drought, low temperature, late leaf spot [LLS], Aspergillus flavus Link, bacterial wilt; high oil and good oil quality) and ICG 442 (resistance to drought, salinity, P deficiency); ICG 12625 and ICG 2381 (resistance to rust, A. flavus; good oil quality); ICG 12697 (resistance to LLS, rust, A. flavus) and ICG 6022 (resistance to early leaf spot [ELS], LLS); ICG 14710 (high oil, Fe, Zn) and ICG 7963 (high protein, Fe, Zn); ICG 11426 (resistance to ELS, LLS, rust) and ICG 5221 (high Fe and Zn and good oil quality). Accessions with adaptation to rainy and/or post-rainy environments were ICG# 434, 5745, 8285, 10036, 11088, 11651, 12625, 15042, and 15419. These accessions are ideal genetic resources that may be used to develop agronomically superior and nutritionally enhanced peanut cultivars with multiple resistances to abiotic and biotic stresses. [ABSTRACT FROM AUTHOR]

In chickpea, bottlenecks associated with its domestication and low use of germplasm in improvement programs have resulted in a narrow genetic base and its vulnerability to abiotic and biotic stresses. The core and mini core collections, representing diversity in the entire collection, have been advocated for enhanced utilization of germplasm in crop improvement. A chickpea mini core (211 accessions) was evaluated for agronomic traits from 2000 and 2001 to 2003 and 2004 in post-rainy seasons under irrigated and non-irrigated conditions. The published information on the response of chickpea mini core accessions to stress revealed that 40 accessions had resistance to abiotic stress, 31 to biotic stress, and 24 had no resistance to either of the stresses. The abiotic and biotic stress resistant groups had six accessions in common. The mini core collection accessions were also a part of composite collection accessions in chickpea, which was genotyped using 48 simple sequence repeats (SSRs; BMC Plant Biol. 8:106, 2008). The agronomic evaluation, stress response, and molecular profiling data on 93 accessions, including four controls, were used to identify genetically diverse germplasm with agronomically beneficial traits. A number of genetically diverse accessions possessing agronomically beneficial traits, such as ICC 440, 637, 1098, 3325, 3362, 4872, 7441, 8621, 9586, 10399, 12307, 14402, 15680, and 15686, which meet breeders' needs, have been identified for use in breeding and genetics to map genomic regions associated with beneficial traits and as source materials for developing high yielding and widely adapted chickpea cultivars with multiple resistance to abiotic and biotic stress. [ABSTRACT FROM AUTHOR]

Chickpea is considered sensitive to salinity, but the salinity resistance of chickpea germplasm has rarely been explored. This study aimed to (i) determine whether there is consistent genetic variation for salinity resistance in the chickpea minicore and reference collections; (ii) determine whether the range of salinity resistance is similar across two of the key soil types on which chickpea is grown; (iii) assess the strength of the relationship between the yield under saline conditions and that under non-saline conditions; and (iv) test whether salinity resistance is related to differences in seed set under saline conditions across soils and seasons. The seed yield of 265 chickpea genotypes in 2005-2006 and 294 cultivated genotypes of the reference set in 2007-2008 were measured. This included 211 accessions of the minicore collection of chickpea germplasm from the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT). The experiments were conducted in a partly controlled environment using a Vertisol soil in 2005-2006 and an Alfisol soil in 2007-2008, with or without 80 m sodium chloride (NaCl) added prior to planting. In a separate experiment in 2006-2007, 108 genotypes (common across 2005-2006 and 2007-2008 evaluations) were grown under saline (80 m NaCl) and non-saline conditions in a Vertisol and an Alfisol soil. In 2005-2006 in the Vertisol and 2007-2008 in the Alfisol, salinity delayed flowering and maturity, and reduced both shoot biomass and seed yield at maturity. There was a large variation in seed yield among the genotypes in the saline pots, and a small genotype by environment interaction for grain yield in both soil types. The non-saline control yields explained only 12-15 % of the variation of the saline yields indicating that evaluation for salinity resistance needs to be conducted under saline conditions. The reduction in yield in the saline soil compared with the non-saline soil was more severe in the Alfisol than in the Vertisol, but rank order was similar in both soil types with a few exceptions. Yield reductions due to salinity were closely associated with fewer pods and seeds per pot (61-91 %) and to lesser extent from less plant biomass (12-27 %), but not seed size. Groups of consistently salinity resistant genotypes and the ones specifically resistant in Vertisols were identified for use as donor sources for crossing with existing chickpea cultivars. [ABSTRACT FROM AUTHOR]

Chickpea is the third most important pulse crop worldwide. Changes in cropping system that necessitate late planting, scope for expansion in rice fallows and the global warming are pushing chickpeas to relatively warmer growing environment. Such changes demand identification of varieties resilient to warmer temperature. Therefore, the reference collection of chickpea germplasm, defined based on molecular characterization of global composite collection, was screened for high temperature tolerance at two locations in India (Patancheru and Kanpur) by delayed sowing and synchronizing the reproductive phase of the crop with the occurrence of higher temperatures ( ≥ 35°C). A heat tolerance index (HTI) was calculated using a multiple regression approach where grain yield under heat stress is considered as a function of yield potential and time to 50% flowering. There were large and significant variations for HTI, phenology, yield and yield components at both the locations. There were highly significant genotypic effects and equally significant G × E interactions for all the traits studied. A cluster analysis of the HTI of the two locations yielded five cluster groups as stable tolerant (n = 18), tolerant only at Patancheru (n = 34), tolerant only at Kanpur (n = 23), moderately tolerant (n = 120) and stable sensitive (n = 82). The pod number per plant and the harvest index explained ≥ 60% of the variation in seed yield and ≥ 49% of HTI at Kanpur and ≥ 80% of the seed yield and ≥ 35% of HTI at Patancheru, indicating that partitioning as a consequence of poor pod set is the most affected trait under heat stress. A large number of heat-tolerant genotypes also happened to be drought tolerant. [ABSTRACT FROM PUBLISHER]

Studies the ureide degradation pathways in intact soybean leaves. Accumulation of ureides in shoots of nitrogen-fixing soybean under water deficit; Controversy concerning the pathway of allantoic acid degradation in soybean; Existence of two degradation pathways within the soybean germplasm.

Highlights: [•] Groundnut germplasm was assessed across varying drought intensities. [•] Drought intensity increased aflatoxin concentration in seeds. [•] Across trials aflatoxin concentration and grain yield reduction were highly correlated. [•] However within trial, aflatoxin and grain yield reduction were unrelated, showing no direct relationship between drought tolerance and resistance to aflatoxin contamination. [•] Mechanisms of drought tolerance and aflatoxin contamination are likely not common. [ABSTRACT FROM AUTHOR]

Abstract: Intermittent drought is the most important yield limiting factor affecting groundnut (Arachis hypogaea L.) production in rain-fed regions of Sub-Saharan Africa and Asia. Improvement of crop adaptation to drought is needed and this starts by having a thorough assessment of a large and representative set of germplasm. In this study, 247 lines belonging to the reference collection of groundnut were assessed under well-watered (WW) and intermittent water stress (WS) conditions in India and Niger for two years, following similar experimental protocols. The WS treatment reduced pod yield (31–46%), haulm yield (8–55%) and the harvest index (1–10%). Besides a strong treatment effect, yield differences within locations and years, were attributed to both genotypic and genotype-by-treatment interactions. Pod yield under WW and WS conditions were closely related in both years (Patancheru, r 2 =0.42 and r 2 =0.50; Sadore, r 2 =0.22 and r 2 =0.23). By contrast, within location and treatment, pod and haulm yields were affected predominantly by genotype-by-year (G×Y) effects, especially under WS. Within treatment across locations and years, pod and haulm yields were mostly ruled by genotypic effects, which allowed identifying a group of entries with contrasting pod yield across locations under WS. However, genotype and genotype by environment (GGE) biplot analyses distinguished India from Niger, suggesting that the selection remains environment-specific and also revealed dissimilarity between years in Niger. A close relationship was observed between yield and pod growth rate (r 2 =0.51), and partition (r 2 =0.33) under WS conditions, whereas no significant relationship was found between yield under WS and SCMR, or specific leaf area (SLA). These results showing a close interaction between the environmental conditions and the genotypic response to intermittent drought shows the necessity to carefully choose environments that truly represent target environments. This is an important result in the current breeding context of marker-assisted recurrent selection or genome-wide selection. This work opens also new ways for the breeding of drought tolerant groundnut, by bringing new highly contrasting lines currently used for crossing and deciphering drought adaptation traits to better understand G×E interactions, while it challenges the relevance of long-time used surrogates such as SCMR or SLA. [Copyright &y& Elsevier]