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Groundnut is sensitive to Fe deficiency under alkaline and calcareous soils and exhibits iron deficiency chlorosis (IDC) causing significant reduction in growth and yield. Genotypes were assessed for IDC related traits such as visual chlorosis rating, SPAD chlorophyll meter reading, chlorophyll and active iron (Fe2+) content across five growth stages and also for productivity traits viz., plant height, number of primary branches, number of pods per plant, pod yield, shelling per cent, 100 seed weight and haulm yield. Comparison between Fe-supplemented and Fe-nonsupplemented condition for IDC related traits showed not much difference among IDC tolerant genotypes across all five growth stages, while significant differences among IDC susceptible genotypes were observed. Maximum reduction in pod yield was observed among IDC susceptible genotypes compared to IDC tolerant and moderately tolerant genotypes. However, recently released variety G 2- 52 with moderate tolerance to IDC and higher yield potential recorded higher pod yield both under Fe applied (1754 kgha–1) and non-applied conditions (1544 kgha–1).

Iron deficiency chlorosis is an important abiotic stress affecting groundnut production worldwide in calcareous and alkaline soils with a pH of 7.5–8.5. To identify genomic regions controlling iron deficiency chlorosis resistance in groundnut, the recombinant inbred line population from the cross TAG 24 × ICGV 86031 was evaluated for associated traits like visual chlorosis rating and SPAD chlorophyll meter reading across three crop growth stages for two consecutive years. Thirty-two QTLs were identified for visual chlorosis rating (3.9%–31.8% phenotypic variance explained [PVE]) and SPAD chlorophyll meter reading [3.8%–11% PVE] across three stages over 2 years. This is the first report of identification of QTLs for iron deficiency chlorosis resistance- associated traits in groundnut. Three major QTLs (>10% PVE) were identified at severe stage, while majority of other QTLs were having small effects. Interestingly, two major QTLs for visual chlorosis rating at 60 days (2013) and 90 days (2014) were located at same position on LG AhXIII. The identified QTLs/markers after validation across diverse genetic material could be used in genomics-assisted breeding.

Iron deficiency chlorosis (IDC) is common among groundnut grown in calcareous and alkaline soils in India, China and Pakistan and causes considerable reduction in pod yield. To identify genetically diverse IDC tolerant accessions, the mini-core collection of groundnut representing geographical diversity was evaluated for IDC response over 2 years in iron-deficient calcareous soils. Enormous genetic variability was evident in the mini-core collection for IDC tolerance-related traits such as a visual chlorotic rating (VCR) and SPAD chlorophyll meter reading (SCMR) across five growth stages. Several IDC tolerant sources belonging to different botanical varieties such as hypogaea bunch (ICG # 5051, 6766, 5286, 6667, 4538, 14008, 5663, 9842, 11855), hypogaea runner (ICG 10479), fastigiata (ICG 10890) and vulgaris (ICG # 11651, 118) were identified. Among the six botanical varieties of groundnut, hypogaea bunch types were found most tolerant to IDC and this is the first report in groundnut. The IDC tolerant sources identified were irrespective of their country of origin. The principal component analysis based on VCR, SCMR, pod yield and its related traits revealed five major principal components that explained 80% of the total variation. The biplot generated using PC1 and PC2 revealed a distinct separation of IDC tolerant genotypes from the susceptible ones. The hierarchical clustering using five major principal components revealed seven major clusters that were mainly based on IDC response of the accessions.

Iron-deficiency chlorosis (IDC) is an important abiotic constraint affecting the growth and yield of groundnut in calcareous and alkaline soils worldwide. The present study investigated the inheritance of IDC resistance among four straight crosses of groundnut involving four IDC susceptible cultivars as females and a common IDC resistant male parent. The F1's of all the four crosses were resistant to IDC indicating the dominant nature of IDC resistance. The F2's of all the four crosses showed a good fit to the ratio of 15 (IDC resistant): 1 (IDC susceptible) and their behavior among the F3's was as per the expected ratio of 7:4:4:1. The IDC resistance in groundnut is under the control of duplicate dominant genes wherein, the presence of a dominant allele at either of the loci results in IDC resistance, while duplicate recessive results in IDC susceptibility. This information would facilitate development of IDC resistant cultivars of groundnut.

A total of 326 pearl millet accessions selected for fodder traits from the world collection at ICRISAT genebank, India were evaluated in rainy, postrainy and summer seasons to identify promising sources for fodder yield. In rainy season, majority of accessions grew significantly tall, produced thick stems, long and broad leaves compared with postrainy and summer seasons. Total tillers per plant were significantly more in rainy and summer seasons than in postrainy season. Significant (P = 0.05) positive correlations were observed among all traits in all seasons except total tillers, which showed significant negative correlation with all other traits but for a few cases. Accessions of cluster 1 flowered early and produced more tillers per plant, while those of cluster 3 flowered late, grew tall, produced thick stems, more leaves per plant, which were long and broad. Promising sources identified include IP 11839 and IP 11840 for plant height and number of leaves per plant, IP 15710, IP 15735 and IP 15752 for stem thickness and leaf width, and IP 3628, IP 15285, IP 15288, IP 15302, IP 15342, IP 15351, IP 15290, IP 20347 and IP 20350 for total tillers per plant. Further testing of these sources of fodder traits at different locations will be very useful.

Iron deficiency chlorosis (IDC) causes a significant reduction in yield of groundnut grown in calcareous and alkaline soils in India. The main aim of the study was to assess genotypic differences for morpho-physiological parameters associated with IDC resistance across different stages and their effect on yield and its related traits. The factorial pot experiment was comprised of two major factors, i) soil-Fe status [normal-Fe, deficit-Fe], and ii) genotypes [five] with differential IDC response, constituting 10 treatments. They were assessed for five morpho-physiological parameters associated with IDC resistance across five crop growth stages and also yield and its related traits. Associations between these traits were also estimated. Under deficit-Fe conditions, IDC resistant genotypes recorded significantly lower visual chlorosis rating (VCR), higher SPAD values, active Fe, chlorophyll content, peroxidase activity, and high yield compared to susceptible ones. Between normal- to deficit-Fe soils, resistant compared to susceptible genotypes showed no change in VCR scores; a lower reduction in SPAD, chlorophyll, active Fe, peroxidase activity, and pod yield. Under deficit-Fe conditions, high yield among resistant genotypes could be attributed to higher seed weight, number of pods and haulm yield, while contrasting reduction in main stem height and number of primaries. The results indicate that for initial large-scale screening of groundnut genotypes for IDC resistance, SPAD values are most ideal while active Fe could be utilized for confirmation of identified lines.

A deep understanding of the genetic control of drought tolerance and iron deficiency tolerance is essential to hasten the process of developing improved varieties with higher tolerance through genomics-assisted breeding. In this context, an improved genetic map with 1205 loci was developed spanning 2598.3&thinsp, cM with an average 2.2&thinsp, cM distance between loci in the recombinant inbred line (TAG 24 &times, ICGV 86031) population using high-density 58K single nucleotide polymorphism (SNP) &ldquo, Axiom_Arachis&rdquo, array. Quantitative trait locus (QTL) analysis was performed using extensive phenotyping data generated for 20 drought tolerance- and two iron deficiency tolerance-related traits from eight seasons (2004&ndash, 2015) at two locations in India, one in Niger, and one in Senegal. The genome-wide QTL discovery analysis identified 19 major main-effect QTLs with 10.0&ndash, 33.9% phenotypic variation explained (PVE) for drought tolerance- and iron deficiency tolerance- related traits. Major main-effect QTLs were detected for haulm weight (20.1% PVE), SCMR (soil plant analytical development (SPAD) chlorophyll meter reading, 22.4% PVE), and visual chlorosis rate (33.9% PVE). Several important candidate genes encoding glycosyl hydrolases, malate dehydrogenases, microtubule-associated proteins, and transcription factors such as MADS-box, basic helix-loop-helix (bHLH), NAM, ATAF, and CUC (NAC), and myeloblastosis (MYB) were identified underlying these QTL regions. The putative function of these genes indicated their possible involvement in plant growth, development of seed and pod, and photosynthesis under drought or iron deficiency conditions in groundnut. These genomic regions and candidate genes, after validation, may be useful to develop molecular markers for deploying genomics-assisted breeding for enhancing groundnut yield under drought stress and iron-deficient soil conditions.

Food and nutritional security will be worsened by climate change-induced high temperatures, droughts and reduced water availability in most agricultural food crops environments, particularly in developing countries. Recent evidences indicate that countries in the southern hemisphere are more vulnerable to food production due to greater frequency of extreme weather events. These challenges can be addressed by: (i) adoption of climate mitigation tools in agricultural and urban activities; (ii) development of heat and drought tolerant cultivars in major food crops; (iii) bringing back forgoten native minor food crops such as millets and root crops; and (iv) continued investment in agricultural research and development with the strong government policy support on native crops grown by small holder farmers. The native crops have inherent potential and traits to cope with adverse climate during the course of its evolution process. Therefore, diversifying the crops should be a prime framework of the climate-smart agriculture to meet the global food and nutritional security for which policy-driven production changes are highly required in developing countries. The adverse efects of climate change on agricultural production need to be addressed by multidisciplinary team and approaches through strong network of research consortium including private sectors and multinational governments for global impact.

Pearl millet is an important staple crop in the semiarid regions of Asia and Africa due to its high nutritive value and adaptation to varying stress conditions. Globally, Pennisetum spp. germplasm is conserved as 66,682 accessons in 97 genebanks, with the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) Patancheru holding the largest collection. Enormous diversity has been reported in cultigen genepool for morphoagronomic traits, resistance to abiotic and biotic stresses, and nutritional traits. Core and minicore collection developed at ICRISAT would facilitate extensive evaluation and identification of trait-specific diverse germplasm. Wide crosses within the primary genepool have been successful to transfer desirable traits, but those involving secondary and tertiary genepool species have often met with limited success. Genomic resources are expected to increase with pearl millet genome sequence due for release and faster developments in next-generation sequencing technologies, which would enhance germplasm management and crop improvement.

Proso, barnyard, little, and kodo millets are highly nutritious with diverse usage. They are well adapted to harsh climatic conditions, require limited inputs, and are the potential crops for food and nutritional security in the context of global climate change. Globally, about 50,000 germplasm accessions of these crops have been conserved, and the largest collections of proso millet are in the Russian Federation and China, barnyard millet in Japan, and kodo and little millet in India. These crops have large variation for yield components and stress tolerance traits. Core collections representing diversity of entire collections of these crops have been developed for identification of new sources of variation for biotic and abiotic stresses, and for quality and agronomic traits for use in crop improvement and genomic studies. Genomic resources are limited in these crops and efforts to develop such resources through high-throughput genotyping approaches and using genomic resources available in taxonomically closest species are required.

Foxtail and finger millets are highly nutritious with diverse usage, well-adapted to marginal lands, and mostly grown by resource-poor farmers. Worldwide >46,000 foxtail millet and >37,000 finger millet germplasm accessions have been conserved, and the largest collections of finger and foxtail millets germplasm accessions are in India and China, respectively. Considerable variation exists for biotic and abiotic stresses, and for quality and agronomic traits for improvement. The entire diversity of these crops has been captured in the form of core, and mini core collections and is being used in genetic and genomic studies for identification of new sources of variation. Genomic resources are available in foxtail millet, while in finger millet these resources are being developed. Use of the genetic and genomic resources need to be accelerated to assist in developing improved cultivars in these crops.

Iron deficiency is an important abiotic constraint reducing the growth and yield of groundnut especially under calcareous soils. Foliar application of Fe-chelates can overcome iron deficiency but it is not economical. Evaluation of 318 recombinant inbred lines (RILs) along with parents for iron deficiency chlorosis (IDC) and productivity traits under iron deficient soils over three years indicated significant genotypic and genotypic x environment interaction (GE) component for both IDC and productivity traits. Among the RILs, range of variation was higher than that of the parents for visual chlorotic rating (VCR), SPAD chlorophyll meter reading (SCMR) and productivity parameters across three years indicated the presence of transgressive segregants. VCR had higher phenotypic and genotypic, variances, heritability and genetic advance as per cent of mean (GAM) in all the three years as compared to SCMR. Among productivity traits, pod yield (g plant–1) had higher PCV and GCV compared to shelling per cent and 100 seed weight. Significant negative correlation between VCR and pod yield per plant indicated effect of IDC on productivity in RILs. Nine lines were superior for both IDC tolerance and productivity traits. This extensive phenotyping of RIL population for IDC tolerance under iron deficient conditions can be used for identification of genomic regions associated with IDC tolerance by genotyping of this RIL population.

A pot experiment with factorial design involving normal and calcareous soil and five genotypes with differential response to iron deficiency chlorosis (IDC) viz., ICGV 86031 and A30b (Resistant), TG 26 (moderately Resistant), TAG 24 and TMV 2 (susceptibe) were tested for various traits like VCR and SCMR, chlorophyll a, b and total chlorophyll, active iron content, specific activity of peroxidase at five different stages and also know the effect of IDC on yield and yield components. Iron deficiency chlorosis resistant genotypes recorded significantly lower VCR, higher SCMR, higher active iron content, chlorophyll a, b and total chlorophyll and peroxidase activity in leaf across all stages compared to susceptible genotypes. A strong and positive correlation was observed between peroxidase activity and leaf iron content. Yield and yield components were significantly reduced in susceptible genotypes compared to resistant genotypes.