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World's vegetable oil demand is increasing day by day and oil seed supply is limited to a dozen oil seed crops on commercial scale. Efforts were made to explore the potential of water melon a traditionally grown native crop of Indian arid zone having oil content over 30% and seed yield potential of 500-600 kg per hectare under rainfed conditions. An analysis was carried out to explore the suitability of watermelon [ (Thunb.)] oil for human consumption on the basis of fatty acid (FA) composition in selected genotypes. Total oil content ranged between 10.0 and 31.0%. Eleven FA were identified in seed oil. Linoleic, stearic, palmitic and oleic acid were found as major FA while myristic, heptadecanoic, arachidic, 9-hexadecenoic and 14-eicosenoic acid was present in traces. Linoleic acid single polyunsaturated FA contributor found in the range of 43.95% (WM-44) to 55.29% (WM-18). Saturated FA content ranged between 32.24 and 37.61%. Significant genetic variation was observed for mono-unsaturated FA. Metabolic capacity to inter-conversion of FA and nutritive value of watermelon oil was described on the basis of ratio of FA group. Total phenolics, antioxidant activity, peroxide value and oxidizability were also estimated along with oxidative stability of oil. Multivariate analysis showed that, oil content has positive correlation with linoleic acid. The Euclidean based UPGMA clustering revealed that genotypes WM-18 is most suitable for trait specific breeding program for high linoleic acid (-6), desaturation ratio and oleic desaturation ratio with higher oil content and lowest palmitic acid.

Cluster bean is an annual drought hardy legume crop mainly cultivated in arid regions receiving scanty (150-400 mm) and erratic rainfall during crop growth period. For the enhancement of genetic diversity in this locally adapted crop, three genotypes HG-2-20 (hispid branched), CAZG-15-6 (branched glabrous) and CAZG 15-3 (single stem, hispid and regular bearing) were irradiated with gamma rays (100-1600 gray) with 100 gray intervals. The mutation rate increased with increasing dose up to 300 gray, there after gradually reduced indicating decline in rate of recovery of mutations with respect to increasing M 1 damage. At higher dose of 800 gray, mutation efficiency drastically reduced with reduced survival and high level of pollen sterility in M 1 generation. Beyond 800 Gy dose all the seedlings died within a few days (15 d) of germination. Based on mutation efficiency and effectiveness a gamma radiation dose between wide ranges (200-700 Gy) was found appropriate for inducing variability. The mutagenesis has generated, a good amount of diversity for economically and agronomically important traits.

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Clusterbean (Cyamopsis tetragonoloba (L.) Taub.), also known as Guar is a widely 14 cultivated dryland legume of Western India and parts of Africa. Apart from being a vegetable 15 crop, it is also an abundant source of a natural hetero-polysaccharide called guar gum or 16 galactomannan which is widely used in cosmetics, pharmaceuticals, food processing, shale gas 17 drilling etc. Here, for the first time we are reporting a chromosome-scale reference genome 18 assembly of clusterbean, from a high galactomannan containing popular guar cultivar, RGC-936, 19 by combining sequenced reads from Illumina, 10x Chromium and Oxford Nanopore 20 technologies. The initial assembly of 1580 scaffolds with an N50 value of 7.12 Mbp was 21 generated. Then, the final genome assembly was obtained by anchoring these scaffolds to a high 22 density SNP map. Finally, a genome assembly of 550.31 Mbp was obtained in 7 23 pseudomolecules corresponding to 7 chromosomes with a very high N50 of 78.27 Mbp. We 24 finally predicted 34,680 protein-coding genes in the guar genome. The high-quality 25 chromosome-scale cluster bean genome assembly will facilitate understanding of the molecular 26 basis of galactomannan biosynthesis and aid in genomics-assisted breeding of superior cultivars.27 28 Introduction:29 Clusterbean (Cyamopsis tetragonoloba (L.) Taub.), also known as guar 1 is a member of 30 Leguminosae family. The common name clusterbean is attributed to its pods which appear in 31 clusters. Previous reports suggest that guar originated in Africa and later spread to the entire 32 South Asian region. In India and Pakistan, clusterbean is cultivated since ancient times for its 33 tender pods which are used as fresh vegetable and the remaining plant serves as fodder 2 . 34Clusterbean is a climate-resilient annual legume and a high potential alternative crop in the 35 marginal lands of arid and semi-arid regions 3 . The genus Cyamopsis includes four species i.e., 36 one cultivated C. tetragonoloba (L.) Taub., two wild relatives C. serrata Schinz, and C. 37senegalensis Guill&Perr, and C. dentate Tarre, and an interspecies hybrid of C. serrata and C.38 senegalensis 4. A mature clusterbean seed is composed of three parts: germ (43-47%), endosperm 39 (35-42%), and seed coat (14-17%). About 80-90% of the endosperm is composed of highly 40 viscous water-soluble hetero-polysaccharide called gaur gum (or) galactomannan, having a 1:2 41 ratio of galactose to mannose 5 . Guar gum is extensively utilized as natural thickener, emulsifier 42 and stabilizers in the food, textile, paper, petroleum and pharmaceutical industry with increasing 43 global demand 6-9 . With the annual production of ~1-1.25 million tons of clusterbean seeds, India 44 accounts for 80% of the global production, with several other countries,