Landraces of vegetable Roselle (Hibiscus sabdariffa var. sabdariffa L.) are under subsistence and commercial cultivation in tribal, rural and peri-urban vegetable farming systems by the tribal folks, small and marginal farmers of south India. Leaf yields of these landraces are low in farmer's conditions either due to poor production potential of landraces or poor agrotechniques. The production potential and the economic value can be enhanced by identifying the promising landraces and their intensive cultivation in the market and truck gardens. In collaboration with National Bureau of Plant Genetic Resources, Regional Station, Rajendranagar, 28 landraces of vegetable Roselle were collected from parts of Andhra Pradesh and Odisha states of India during 2010-2011. These landraces were evaluated in a randomized block design with three replications during summer 2013 at Vegetable Research Station, Rajendranagar to assess the production potential and the genetic variability for various agro-economic traits. The variation recorded within the landrace germplasm for plant height, total biomass, leaf yield, stalk yield, leaf-stalk ratio and harvest index show its potential for use in the genetic improvement. The landraces RNR-16, RNR-20 and RNR-27 were promising as indicated by the high leaf production potential of 14.22, 12.72 and 11.85 g plant-1 , respectively. High estimates of heritability coupled with high genetic advance as percent of mean for plant height, total biomass, leaf yield, stalk yield and leaf-stalk ratio indicating the possibility to improve these agro-economic traits through selection programs. Selection is effective for plant height, leaf yield, stalk yield, leaf-stalk ratio and total biomass in vegetable Roselle.

A field experiment was conducted to know the gene action and selection of superior parents of velvet bean for hybridization. The heterosis and combining ability study was carried out using 6x6 half diallel mating design excluding reciprocals. Combining ability analysis revealed that magnitude of sca variance was greater than gca variance suggesting the predominance of non additive gene action for most of the traits except days to 50 per cent flowering, number of flowers per inflorescence, number of pods per bunch and 100 seed weight where gca variance was greater than sca variance indicating predominance of additive gene action. Based on gca effects, parents Arka Dhanwantari, IIHR Selection 8 and IIHR Selection 2 were best general combiners for the traits such as number of flowers per inflorescence, pod length, pod weight, number of bunches per plant, number of pods per bunch, dry pod yield and seed yield per plant which can be used in future breeding programme. Specific combining ability studies indicated cross IIHR Selection 2 x IIHR Selection 8 as best specific combiner for the economically important traits viz., pod length, pod weight, dry pod yield per plant and seed yield per plant. The cross IIHR Selection 8 x IIHR Selection 3 was recorded high heterotic effects for dry pod yield per plant, seed yield per plant and test weight of the seed. The cross IIHR Selection 2 x IIHR Selection 8 as superior hybrid as recorded high heterobeltiosis for days to 50% flowering, pod length, pod weight, dry pod yield per plant and seed yield per plant and days to maturity which can be exploited in future breeding programme.

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Velvet bean is an important medicinal legume, its seeds are prominent source of L-Dopa. The present investigation on genetic diversity assessment of 58 germplasm of velvet bean by using 11 ISSR markers. Out of 63 amplified products 59 were showed polymorphism and 4 were monomorphic with an average of 5.7 bands amplified per primer. According to band statistics and efficiency parameters showed the primers UBC 827, UBC 834 and UBC 836 were more efficient. The highest genetic similarity values (0.90) were observed between IIHR MP 102 and IIHR MP 74-3. In dendrogram germplasm grouped into two major clusters at 63 per cent similarity. Among the germplasm, IIHR Selection 4, IIHR Selection 10, IIHR MP 9, IC 33243 and IIHR MP 7 were found to be distinctly divergent, can be used in the further breeding programme.

Fifty eight germplasm of Mucuna was analysed for L-Dopa using ultra high performance liquid Chromatography. L-Dopa ranges from 2.94% in IC 332432 to 6.91% in IIHR MP62-1. Low L-Dopa accessions identified IC 332432 (2.94%) and IIHR MP95 (2.98%) was highly beneficial to consume as food with proper processing or boiling. The accessions having high L-Dopa is highly beneficial to the industries for preparation of drugs. High L-Dopa accessions IIHR MP62-1(6.91%), IIHR MP21 (6.77%), IIHR MP63-1(6.76%) and IIHR MP102 (6.57%) were itchy types and important for drug industry. Hence these high L-Dopa accessions can be utilised in future breeding programme of Mucuna to develop high yielding cultivars coupled with high L-Dopa. Correlation coefficient analysis revealed that L-Dopa has significant negative association with pod length indicates selection of smaller pods was a measure of selection index to obtain high L-Dopa accession could be used in breeding programme of velvet bean.