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Despite the importance of okra, as one of the important vegetable crop, very little attention has been paid to its genetic improvement using advanced biotechnological tools. The exploitation of marker assisted breeding in okra is often limited due to the availability of a few molecular markers, the absence of molecular genetic-map(s), and other molecular tools. Chromosome linkage-groups were not yet constructed for this crop and reports on marker development are very scanty and mostly hovering around cultivar characterization. Besides, very little progress has been observed for transgenic development. However, high throughput biotechnological tools like chromosome engineering, RNA interference (RNAi), marker-assisted recurrent selection (MARS), genome-wide selection (GWS), targeted gene replacement, next generation sequencing (NGS), and nanobiotechnology can provide a rapid way for okra improvement. Further, the etiology of many deadly viral diseases like the yellow vein mosaic virus (YVMV) and okra enation leaf curl virus (OELCV) in okra is broadly indistinct and has been shown to be caused by various begomovirus species. These diseases cause systemic infections and have a very effective mode of transmission; thus, preventing their spread has been very complicated. Biotechnological interventions have the potential to enhance okra production even under different viral-stress conditions. In this background, this review deals with the biotechnological advancements in okra per se along with the begomoviruses infecting okra, and special emphasis has been laid on the exploitation of advanced genomic tools for the development of resistant varieties.

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Paucity of research on the development of tomato hybrid having desirable post harvest/or processing quality in the tropics compel to undertake this study. Therefore, the present investigation was undertaken to identify potential donors and crosses, to study the extent of heterosis and dominance behaviour, and to ascertain the genetic control of fifteen yield components and post harvest quality traits through line x tester mating design in tomato. Non-additive gene action controlled all characters studied, suggesting heterosis breeding for their improvement. Among parental lines, CLN2777-G’ and ‘FEB-2’ were the best general combiners for yield and processing traits and could be utilized further in tomato breeding programme. Crosses (‘CLN2768-A x A.C.AFT’ and ‘CLN2777-G x FEB-2’) showing high specific combining ability and yield involved parents showing high general combining ability for fruit yield per plant and other horticultural traits. All 9 F1 hybrids had significantly higher number of fruits per cluster and number of fruits per cluster over both mid-and better-parental values, while for the other traits, hybrids expressed average heterosis in both directions. The maximum extent of heterobeltiosis (53.56%) was found in lycopene content of fruit followed by number of fruits per cluster (32.59%) and fruit yield per plant (31.77%). The performances of the hybrids illustrated the presence of various degrees of dominance effects i.e., partial to overdominance /or no dominance. We could able to improve processing quality in spite of yield in the cross (‘CLN2777-G x FEB-2’) which can substantially make a dent for processing industry in the tropics.

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Whitefly-transmitted begomoviruses cause severe diseases in numerous economically important dicotyledonous plants. In recent years, okra enation leaf curl disease (OELCuD) emerged as a serious threat to okra (Abelmoschus esculentus L. Moench) cultivation in the Indian subcontinent. The present study reports the association of a monopartite begomovirus (bhendi yellow vein mosaic virus - BYVMV) and betasatellite (bhendi yellow vein mosaic betasatellite - BYVB) with OELCuD in the Mau region of Uttar Pradesh, India. The BYVMV alone inoculated N benthamiana and A esculentus cv. Pusa Sawani plants developed mild symptoms. Co-inoculation of BYVMV and BYVB resulted in a reduced incubation period, an increased symptom severity and an enhanced BYVMV accumulation (by Southern hybridization and qPCR). This is the first study which satisfies Koch’s postulates for OELCuD in its natural host. Activities of various antioxidative enzymes were significantly increased in the virus inoculated okra plants. Differential responses in various biochemical components (such as photosynthetic pigments, phenol, proline, sugar) in diseased okra plants were observed. This change in phytochemical responses is of significant importance in understanding its impact on virus pathogenesis and disease development.

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