To assess the possible effect of nodule mining on deep-sea environment, the Indian Deep-sea Environment Experiment (INDEX) was undertaken in the Indian Basin. The present investigation is a part of the disturbance and recolonization study. Pre-and post-disturbance sediment samples were collected from 21 stations between 10 0 01' -10 0 03' S and 75 0 59' -76 0 02' E at water depths of 5300 -5350 m to assess the effect of benthic disturbance. There was a significant change in the composition and biomass of macrofauna after the disturbance. Post-disturbance vertical profiles indicated a 63% reduction in the numerical count in the top 0-2-cm layer and high aggregation of macrofauna in deeper (5-10-cm) sediment layer. The impact of the disturbance was severe, as the mean biomass of macrofauna was significantly reduced in the disturbed area, probably due to the displacement and /or mortality caused by the benthic disturber.

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Inter and intra-specific hybridization is a powerful breeding method for crop improvement and it has potential to broaden the genetic base of the cultivated species. M. charantia var. muricata is considered as a wild progenitor of bitter gourd (M. charantia) and it has important novel genes for biotic and abiotic stress tolerance. In the present experiment, conducted during the 2016–17 and 2017–18, intra-specific hybrids were produced among M. charantia var. charantia and M. charantia var. muricata and these were characterized for plant morphology, pollen-pistil compatibility, cytology and molecular relation among the parents and hybrids. In both direct and reciprocal crosses, the crossability percent was nearly 90% with high percent of pollen viability. The morphological traits of the parents were highly diverse and the hybrids showed intermediate pattern of character expression. The pollen-pistil behaviour and compatibility reaction were studied for the first time and observed higher per cent of compatibility in direct cross (M. charantia var. charantia × M. charantia var. muricata; 90.98%) and comparatively lower in reciprocal cross (M. charantia var. muricata × M. charantia var charantia; 84.43%). Cytological and molecular marker (SSR) techniques were used for hybridity confirmation.

Based on Nei's genetic distance Nemipterus peronii and Nemipterus japonicus showed a greater affinity to Parascolopsis aspinosa than to the other Nemipterus species studied. Significant differences between the Indian west and east coast samples of N. japonicus were detected. Polymorphic (P<0·95) and diagnostic loci suitable for stock delineation and species identification were observed.

Genetic variability has been greatly valued in yard-long bean, due to their narrow genetic base. To diversify the genetic base, yard long bean genotypes were evaluated to quantify the variation, to assess the extent of association between the yield complaint traits, diversity and for their utilization in crop improvement programmes. High phenotypic and genotypic coefficient of variations, heritability coupled with genetic advance over mean were observed most of the traits except internodal length, days to first and 50 per cent flowering, days to first and last picking, seeds per pod. Correlation and path analysis of variables namely pod length, pod width and pods per plant contributes high positive significant association with pod yield per plant, and maximum direct and indirect effect recorded for pods per plant, green pod length and green pod width. The genotypes were grouped into 12 clusters, the maximum divergence recorded between genotypes of Cluster XI and Cluster XII for traits pod yield per plant, vine length and yield per plot and pod length contributed high towards total divergence, the genetically diverse genotype of these clusters aids in the creation of larger recombinants, and would be an aid in the genetic improvement of yard-long bean genotypes.

Thepresence of tubercles and pattern of ridges (continuous vs discontinuous) are important traits of bitter gourd which determine market price in India.The tuberculate fruits with broken or discontinuous ridges have more unit price than the non-tuberculate and continuous ridged fruits. In the present study, two different botanical varieties of Momordica charantia var. charantia (DBGS-2 and DBGS-54) and M. charantia var. muricata (DBGS-34) were used for inheritance study and molecular tagging of fruit tubercles and fruit ridgeness pattern. The findings revealed the monogenic control for both the traits. The bi-parental mapping populations (F2) were developed from the crosses DBGS-54×DBGS-34 and DBGS-2×DBGS- 34 for tagging of tuberculate (Tb) and continues ridgeness (cr) locus, using SSR markers. The single plant analysis of F2 population (derived from DBGS-54×DBGS-34) based on SSR markers found McSSR-20 was linked to fruit tubercles gene (Tb) at 12.50 cM and another SSR marker JY004 in the cross DBGS-2×DBGS-34 was found linked with fruit ridgeness pattern (cr) gene at a distance of 19.6cM. It is the first report of SSR markers linked to fruit tubercles and ridgeness which will be helpful further in fine mapping of these traits with more PCR based markers. These findings will help in differenciating the genotypes with tubercles and pattern of ridgeness at the early stage of the crop and can be used in accelerating trait specific breeding programme in bitter gourd.