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Salinity is one of the major abiotic stress limiting rice productivity under marginal environments. The progress in development of salinity tolerant rice varieties is slow due to complex nature of tolerance mechanisms determining performance under salinity. In the present study, efforts were taken to generate NILs of a popular rice genotype Improved White Ponni exhibiting increased tolerance against salinity through marker assisted introgression of ‘Saltol’, a major effect QTL of FL478. IWP-Satol NILs exhibited enhanced tolerance against salinity under hydroponic conditions. MABB approach accelerated the development of NILs with high recovery of recurrent parent genome within 2–3 backcrosses. Genotyping and phenotyping of BC3F1 progenies resulted in the identification of elite NILs of IWP harboring Saltol loci and possessing > 90% of recurrent parent genome recovery. Selected NILs viz., 5-35, 5-36 and 5-45 that carried the Saltol loci were screened under field conditions for their agronomic traits. NIL # 5-36 exhibited superior agronomic performance (58% increased yield over IWP under saline conditions) and superior grain/cooking quality traits than that of IWP.

The caloric needs of the global population are solely dependent on only 30 crops including rice, wheat, and maize. It is important to diversify and ensure the global food supply by enhancing the wide adaptation of nutritionally important vegetable crops. Focusing on the underutilized and locally available vegetable crops would meet the need of eradicating malnutrition and food security for the local population and small-hold farmers. With the advent of long-read sequencing technologies, several orphan crops and crops with complex genetic nature are being explored and genome resources are made available for crop improvement. Moringa oliefera is a well-known medicinal and nutritive plant which is getting adequate attention in recent years. Functional analytical tools including genome, transcriptome, metabolome, and proteome were made available for moringa; besides diversity analysis, evolutionary and syntenic studies were also reported. With an objective of exploring the available resources of an important nutritive crop and evaluating the need to enhance the functional studies further, this chapter reviews the application of long-read sequencing and their application in moringa genomics for its wider utilization in pharma industries.

Increases in rice productivity are significantly hampered because of the increase in the occurrence of abiotic stresses, including drought, salinity, and submergence. Developing a rice variety with inherent tolerance against these major abiotic stresses will help achieve a sustained increase in rice production under unfavorable conditions. The present study was conducted to develop abiotic stress-tolerant rice genotypes in the genetic background of the popular rice variety Improved White Ponni (IWP) by introgressing major effect quantitative trait loci (QTLs) conferring tolerance against drought (qDTY1.1, qDTY2.1), salinity (Saltol), and submergence (Sub1) through a marker assisted backcross breeding approach. Genotyping of early generation backcrossed inbred lines (BILs) resulted in the identification of three progenies, 3-11-9-2, 3-11-11-1, and 3-11-11-2, possessing all four target QTLs and maximum recovery of the recurrent parent genome (88.46%). BILs exhibited consistent agronomic and grain quality characters compared to those of IWP and enhanced performance against dehydration, salinity, and submergence stress compared with the recurrent parent IWP. BILs exhibited enhanced tolerance against salinity during germination and increased shoot length, root length, and vigor index compared to those of IWP. All three BILs exhibited reduced symptoms of injury because of salinity (NaCl) and dehydration (PEG) than did IWP. At 12 days of submergence stress, BILs exhibited enhanced survival and greater recovery, whereas IWP failed completely. BILs were found to exhibit on par grain and cooking quality characteristics with their parents. Results of this study clearly demonstrated the effects of the target QTLs in reducing damage caused by drought, salinity, and submergence and lead to the development of a triple stress tolerant version of IWP.

Rice varieties possessing short slender grains with aroma is highly preferred by the farmers. Most of the non-basmati rice varieties are traditional genotypes possessing poor yield and undesirable characteristics like lodging, susceptibility against pests/diseases/abiotic stresses which necessitates accelerating development of such varieties. The present study was undertaken with an aim of validating SSR markers linked to grain length in an F2 population derived between Pusa Basmati 1 (long slender grain) and CBMAS1405 (short slender grain). Genotyping and phenotyping of F2 progenies revealed that two SSR markers viz., RM11 and RM336 were found to be linked to qGRL7.1 and qGRL7.2 respectively with a phenotypic effect (R2) of 7.9% and 16.5%. Genotyping and phenotyping of F2 progenies of CBMAS14065 x Pusa Basmati 1 led to the identification of two agronomically superior lines viz., 224-7 (5.2 mm) and 224-9 (7.7 mm) harboring short grains with aroma and high yield potential.

Cluster bean (Guar) is the major source of industrial gum. Knowledge on the molecular events regulating galactomannan gum accumulation in guar will pave way for accelerated development of gummy guar genotypes. RNA Seq analysis in the immature seeds of contrasting cluster bean genotypes HGS 563 (gum type) and Pusa Navbahar (vegetable type) resulted in the generation of 19,855,490 and 21,488,472 quality reads. Data analysis identified 4938 differentially expressed genes between the gummy vs vegetable genotypes. A set of 2241 genes were up-regulated and 2587 genes were down-regulated in gummy guar. Significant up-regulation of genes involved in the biosynthesis of galactomannan and cell wall storage polysaccharides was observed in the gummy HGS 563. Genes involved in carotenoids, flavonoids, non mevalonic acid, terpenoids, and wax metabolism were also up-regulated in HGS 563. Mannose and galactose were the major nucleotide sugars in Pusa Navbahar and HGS 563 immature seeds. Immature seeds of HGS 563 showed high concentration of mannose and galactose accumulation compared to Pusa Navbahar. qRT-PCR analysis of selected genes confirmed the findings of transcriptome data.

Engineering transcription factors (TF) hold promise in enhancing abiotic stress tolerance in plants. In this study, one of the popular rice varieties of South India, namely ADT 43, was engineered with a TF AtDREB1A driven by a stress-inducible rd29A promoter. PCR and Southern hybridization were employed to confirm the integration and copy number of the transgene. Transgenic lines (T1) of ADT 43 showed enhanced tolerance to drought and salinity compared to the non-transgenic ADT 43. Transgenic lines were found to maintain higher RWC %, lower leaf temperature, and partially closed stomata, enabling better survival under stress conditions. qRT-PCR analysis revealed the strong induction of AtDREB1A transcripts during drought. Transgenic lines of ADT 43 exhibited increased germination and retention of chlorophyll in their leaves under salinity. Evaluation of transgenic lines under transgenic screen house conditions revealed that line # A16 exhibited on par agronomic performance against its non-transgenic counterpart under normal conditions. Under drought, non-transgenic ADT 43 showed &gt, 20% reduction in the total number of spikelets per panicle, whereas transgenic line # A16 registered only a 2% reduction. Non-transgenic ADT 43 recorded 80% yield reduction under drought, whereas line # A16 recorded only 54% yield loss. The above results demonstrated the effectiveness of controlled expression of DREB1A in regulating dehydration responses in rice.