Rice Bean Genotypes Research Articles

A cluster analysis of Ricebean (Vigna umbellata (Thumb.) Ohwi and Ohashi) Accessions with Specified NaCl Salt Concentration at Seedling Stage under Controlled Conditions

The Ricebean is still seen as a crop that is underappreciated and mistreated. The term salinity describes the buildup of soluble salts in soils, which results in saline soils. The Department of Plant Breeding and Genetics, Faculty of Agriculture, West Bengal, India, used a completely randomized block design (CRBD) and a factorial pattern with three replications to conduct this experiment in a growth chamber. In the specified salt concentration of 120 mM of NaCl salt, data were gathered on a variety of seedling growth traits. D2 values should be lower within a cluster than between clusters. The distance between clusters within cluster III (462.54) is the highest, followed by cluster II (294.43) and cluster I (55.88). As a result, these two groups are more diverse, and hybridization between genotypes in these clusters would facilitate gene transfer. The gap between clusters III and II, VI and I, and clusters VI and IV had the largest intra-cluster distance. The shortest inter-cluster distances were between clusters IV & I, V & I, and V & II. Except for leaf fresh weight, shoot dry weight, root dry weight, and leaf dry weight and on germination percentage, relative reduction of dry weights, tolerance index (TI), and salinity susceptibility index (SSI) of various seedling traits, genotypes belonging to cluster I were found to have the least relative reduction for most characters. Therefore, it may be assumed that the genotypes KRB-10, KRB-271, KRB-189, KRB-273, KRB-77, KRB-81, KRB-95, and KRB-70, which belong to this cluster I, will be tolerant to salinity. Similar to this, twelve genotypes from cluster IV—KRB-56, KRB-211, Bidhan-1, KRB-73, KRB-102, KRB-66, KRB-272, KRB-104, KRB-274, KRB-44, KRB-39, and Bidhan-2—had the highest relative reduction for the majority of the characters. The aforementioned results showed that although the majority of the Ricebean genotypes under investigation had a wide range of individual qualities, when the constellation of traits was considered as a whole, they also belonged to different groups.

Nutritional and nutraceutical potential of rice bean (Vigna umbellata) -a legume with hidden potential.

In the recent years there has been paradigm shift in global agriculture for the exploration of different underutilized crops as future potential crops. Rice bean [Vigna umbellata (Thunb.) Ohwi and Ohashi] one of the lesser known pulses among Vigna species has gained attention during last decade as food and nutritional security crop. Rice bean seeds are well-balanced source of beneficial constituents such as protein, carbohydrates, minerals, vitamins, polyunsaturated fatty acids (PUFAs) and anti-oxidants for health benefits and combating malnourishment in human. In the present investigation, seeds of 15 diverse rice bean accessions from north-western Himalayan region were analyzed for nutrients, anti-nutrients and nutraceutical traits. Significant differences were observed among genotypes for different traits. The rice bean genotypes revealed variation for major quality traits including total carbohydrates (50.56-56.87%), crude protein content (22.56-25.97%) and lipid content (1.87 to 3.17%) with the higher proportion of linolenic acid followed by linoleic acid which are nutritionally desirable PUFAs. The genotype IC-548758 revealed higher proportion of desirable quality traits. Among protein fractions, globulins and albumins constituted major seed storage protein fraction in rice bean seeds. The wide range variation was also observed for anti-nutrients like including raffinose family oligosaccharides (RFOs), phenolics, tannins, trypsin inhibitor (TI), phytic acid, lipoxygenase activity and saponin content among genotypes. Insignificant correlation among iron, zinc, magnesium and manganese revealed good selection accuracy for genetic biofortification program in rice bean. In summary, the genotype IC-548757, IC-548760 and IC-548770 revealed lower proportion of anti-nutrients, whereas, the genotype IC-548759 and IC-548757 revealed higher level of free radical scavenging activity indicating nutritional and nutraceutical superiority of these genotypes. Overall, the study revealed nutritional superiority of genotype IC-548770, IC-548758 and IC-548760 with balanced proportions of nutrients and anti-nutrients. Rice bean legume has the potential to support more sustainable and resilient food and nutritional security in future. Our study highlights the potential of different rice bean genotypes as functional ingredients for future food and nutritional security programmes.

Stability analysis of yield and yield related traits in ricebean [Vigna umbellata (Thunb.) Ohwi and Ohashi

A study on stability analysis was carried out in 30 diverse genotypes of ricebean (Vigna umbellata Thunb.) in eastern hill region of India. Significant differences among the genotypes over the years were observed for all the three traits studied. The first two principal components axis (IPCA1, 90.4% and IPCA2, 9.6%) could explain 100% of the total of the interaction variation. Correlation study showed that the stability parameters are highly associated with each other (p < 0.01). Multi trait stability index and genotype selection along with strength and weakness view of the genotypes to the traits inferred higher productivity of BSKB 28 (G29) for number of pods/plant and seed yield/plant and Ukhrul 15 (G17) for number of seeds/pod. Different stability measures selected seven genotypes, namely, Bete 6 (G22), IC002567 (G8), Ukhrul 6 (G13), Ukhrul 14 (G16), Ukhrul 15 (G17), Bete 4 (G21) and BSKB 3 (G28) as the most desirable and stable performing with good yield over the years.

Crossability Barriers in Interspecific Hybridization of Ricebean [Vigna umbellata (Thunb.) Ohwi and Ohashi] with Other Vigna Species

Background: Ricebean [Vigna umbellata (Thunb.) Ohwi and Ohashi] is a multipurpose grain legume of Mid-Himalayan region mainly cultivated for food, fodder, green manure and has emerged as a good alternative to other pulse crops such as blackgram and greengram which do not flourish in this region due to their susceptibility to cold temperature stress. It is well reported that the nutritional value of ricebean is higher as compared to many other legumes of the Vigna family and has some superior qualities greater than greengram, blackgram and cowpea. It is also resistance to drought, diseases and pests specially the storage pests during growth period and possesses high percentage of seed viability. Despite having all the favourable traits, it is not much popular among the farmers due to the late maturity and indeterminate growth habit. Instead, farmers prefer other crops which fit easily into their cropping pattern and are easy to harvest. A little genetic improvement with respect to maturity and growth habit can revive its cultivation and show great results in its production as a valuable crop. Thus, the present investigation was formulated to introgress desired traits from mash and adzukibean into otherwise high yielding ricebean genotypes using inter-specific hybridization. Methods: The present investigation involves the inter-specific hybridization among three Vigna species viz, ricebean (Vigna umbellata), blackgram (Vigna mungo) and adzukibean (Vigna angularis). In the year 2017, six genotypes of ricebean (RBHP-36, RBHP-38, RBHP-43, RBHP-61, RBHP-107 and RBHP-108) were crossed with two genotypes of blackgram (HimMash-1 and Palampur-93) and one genotype of adzukibean (HPU-51) in glasshouse conditions. Result: The study revealed that successful crosses were possible only between ricebean and blackgram. All the Inter-specific crosses showed very low pod set percentage ranging from 0 -4% and F1 germination percentage ranging from 20-42%. Pod set percentage and pods harvested varied with combinations of two parental cultivars of each species for most of the inter-specific hybrids. The successful pod set was observed in 16 out of 36 inter-specific crosses. Highest crossability was observed in blackgram and ricebean crosses. Crossing of adzukibean with ricebean showed poor or no pod set among the entire cross combinations which are attributed to early embryo abortion and degeneration during embryogenesis.

Rice bean (Vigna umbellata Thunb. Ohwi and Ohashi) protection against Callosobruchus maculatus F.” by presence of protein profile

To identify defence responses of rice bean against Callosobruchus maculatus, 10 genotypes of rice bean and a mungbean variety, PAU 911 as susceptible check were evaluated. The rice bean genotypes were found to restrain the growth and development of C. maculatus at different larval stages. To justify these results, seeds of different test genotypes were examined for the presence of plant protease inhibitors which inhibit insect proteases causing reduction in the availability of amino acids necessary for their growth and development. Trypsin, chymotrypsin and cysteine protease inhibitor content was significantly higher in rice bean genotypes which ranged from 299.99 to 342.97 TIU g−1 seeds, 235.07 to 251.45 CIU/g seeds and 1060.70 to 1574.99 CPIU/g seeds, respectively as compared to mungbean variety, PAU 911 (235.52 TIU/g seeds, 217.91 CIU/g seeds and 499.99 CPIU/g seeds, respectively). The protein profile showed a polypeptide band of 25–30 kDa corresponding to presence of protease inhibitors in rice bean genotypes except PAU 911. The results indicate that protease inhibitors in different genotypes of rice bean are very effective against C. maculatus.

Studies on efficacy of various <em>in vivo</em> and <em>in vitro</em> techniques on crossability and pod setting percentage in <em>Vigna mungo</em> x <em>V. umbellata</em> hybridization

The present investigation was carried out with objective to study the efficacy of various in vitro and in vivo techniques for the success of interspecific hybridization between urdbean and ricebean. Interspecific crosses were attempted between three genotypes of urdbean i.e. HPBU-111, Him Mash-1 & Palampur-93 and three genotypes of ricebean i.e. PRR-1, PRR-2 & VRB-3.The study of effect of immuno- suppressants revealed that amino caproic acid at 1000 ppm was found to be the most efficient immuno- suppressant in all the three combination for achieving maximum per cent of pod set. Four minutes of UV irradiation treatment to pollen gave maximum pod setting in Palampur-93 x PRR-2 and Him Mash-1 x VRB-3. The present study revealed the presence of pre-fertilization barriers in interspecific crosses between urdbean & ricebean and were confirmed by the low frequency of pod set. Both the parents involved in interspecific hybridization shows differential genotypic response which indicates the use of more number of genotypes of urdbean and ricebean.

Correlation between biophysical seed characteristics of rice bean, Vigna umbellata (Fabaceae: Faboideae: Phaseoleae) and the development of Callosobruchus maculatus (Coleoptera: Chrysomelidae: Bruchinae)

The bruchid, Callosobruchus maculatus is a serious pest of stored pulses. Four biophysical seed characteristics viz. Seed size, texture of seed surface, thickness of seed coat and seed hardness of 10 genotypes of rice bean, a wild pulse crop were investigated for assessing mechanism of resistance against C. maculatus. Oviposition preference and larval penetration in seed coat did not differ significantly among different test genotypes. Highest number of larvae which developed up to last larval/pupal instar were observed in susceptible check variety of mungbean, PAU 911 (30.00) and lowest in rice bean genotype, LRB 535 (0.83). Highest and lowest seed weight was noticed in rice bean genotype, LRB 529 (6.81 g) and PAU 911 (3.88 g), respectively. Almost similar seed coat thickness was recorded among different test genotypes. Maximum seed hardness was noted in genotype LRB 507 (6.45 kg) whereas minimum in PAU 911 (2.00 kg) among all test genotypes. Any remarkable correlation of biophysical seed characteristics of test genotypes with ovipositon, larval penetration and development of C. maculatus was not observed. Thus, biophysical seed characteristics of rice bean did not suggest to play a vital role in imparting resistance against C. maculatus.

Screening of rice bean genotypes against major insect pests and avoidable yield losses

Screening of rice bean genotypes against major insect pests and avoidable yield losses

Genetic divergence, path coefficient and cluster analysis of ricebean (Vigna umbellata) genotypes in the mid-altitudes of Meghalaya

One hundred and twenty germplasm of ricebean [Vigna umbellata (Thunb) Ohwi and Ohashi] were evaluated during 2015-16 and 2016-17 to study the yield related traits in ricebean in the mid-altitudes of Meghalaya. Luxuriant ricebean growth with a wide spectrum of variability for plant height, number of branches per plant, days to flowering, number of pods per plant and 100 seed weight was observed. The genotypic variance was moderate to high for the said characters which resulted in moderate to high heritability and genetic advance values. Grain yield/plant was positively and significantly correlated with number of clusters per plant, number of pods per plant and 100 seed weight. Moderateto high heritability and the genetic advance of these plant characters vis-a-vis their positive association and direct positive effect on grain yield/plant suggested for their consideration during selection of high yielding genotypes. All the tested ricebean genotypes could be grouped into seven distinct clusters. An analysis of the percentage contributionof individual characters towards genetic diversity revealed that 100-seed weight and days to 80% maturity, days to 50% flowering were the major characters contributing to genetic diversity in ricebean. Based on the results we found genotype CHAK HAWAI-2 may be used as parent for developing long pod with bold seed cultivar. Genotype ChakHawai-31 may be used as parent for developing high yielding genotypes. Genotype BKSB-23 had less bold seed but, high yield and may be used as parent for developing small seed and high yielding variety.

Studies on cross compatibility in interspecific crosses of Vigna radiata × Vigna umbellata species

The present study was undertaken to study the crossability barriers in interspecific crosses of Vigna radiata × Vigna umbellata. The basic materials of this experiment comprising of five mungbean MYMV Susceptible genotypes and five rice bean MYMV resistant genotypes. Interspecific crosses were attempted by utilizing rice bean genotypes as male parents and mungbean genotypes as female parents. The successful pod set was observed on 12 crosses out of 25 interspecific crosses of Vigna radiata and Vigna umbellata. The results revealed that highest crossability per cent was recorded in the crosses Yellowmung × KBR-1 (17.30 %), DGGV-2× RBL-35 (16.0%), Selection-4×KBR-1 (11.80%), Chinamung × KBR-1 (11.0%) and BGS-9× RBL-35 (10.20%) which were considered as successful crosses. This suggests that the parents of these four interspecific cross combinations may be ideal for transfer of useful genes across the two divergent species and to broaden the genetic base of interspecific hybrid and further, the existence of moderate hybrid pollen fertility (78.24%) coupled with moderate seed germination percentage (36.84%), lower hybrid lethality (21.43%) and lower hybrid breakdown (7.14%) was observed in Chinamung × KBR-1 followed by cross Selection-4 ×KBR-1. In the present investigation prominent observation noticed are strong pre-fertilization as well as post fertilization barriers were present in the cross between V. radiata and V. umbellata, while, growth and lethality of interspecific hybrid seedlings were influenced by the genotypes of both the parental species.

Character Association Study Among Components of Green Fodder Yield in Ricebean

Ricebean has been categorized as underutilized crop despite its nutritive quality and fodder yielding ability benign higher than other legumes of Vigna family. In addition to its nutritive value, this crop is fairly resistant to drought and flood conditions. The purpose of this paper is to provide important traits for direct selection of fodder yielding ricebean genotypes through analysis of phenotypic and genotypic association and path coefficient. In the present study, the degree of association between yield and yield contributing attributes were estimated in 85 germplasm lines for nineteen quantitative traits so that direct selection of the promising traits may be effective for the improvement of yield potential of future genotypes of ricebean. Correlation studies indicated that green fodder yield per plant was significantly and positively associated with green fodder yield per day, number of leaves per plant, number of branches per plant, crude protein yield per plant, crude protein yield per plant per day, dry matter yield per plant, dry matter yield per plant per day, leaf stem ratio and plant height at both genotypic and phenotypic levels. Path coefficient revealed that green fodder yield per plant per day has highest direct effect and significant positive correlation towards yield. Other traits, crude protein yield per plant, dry matter yield per plant per day, days to 50% flowering, days to flower initiation and plant height were also found to be important fodder yield indicators in ricebean.

Comparative assessment of ssr markers derived from different sources in genetic diversity analysis of Vigna genotypes

Mung bean (Vigna radiata (L.) Wilczek), also known as green gram, is an important food legume crop and provides an inexpensive source of dietary protein. Due to lack of sufficient variability and its importance in Asian countries there is need of broadening its genetic base. Genetic diversity among 21 Vigna genotypes of mung bean, rice bean and urd bean was assessed using SSR markers derived from genomic sequences of azuki bean (Ced) and mung bean (VR) and EST sequences of mung bean (MBM). Of the 67 SSR markers selected, 45 were found polymorphic among different genotypes which yielded 138 alleles of which 16 were mung bean specific, 27 urd bean specific and 17 rice bean specific alleles. Azuki bean derived SSRs (Ced) were more polymorphic. PIC value was similar in three sets of SSRs. Number of observed and effective alleles were more in Ced markers along with high value of various other parameters like EMR (3.6), MI (1.26), RP (2.7), H(0.33), H(0.62), and H(0.6), calculated to identify effectiveness of markers. Dissimilarity analysis divided mung bean and rice bean genotypes into two subclusters while 12 genotypes of urd bean formed two clusters.

Genetics of yield and its components in rice bean under mid altitude areas of Mon district Nagaland India

Genetic variability, correlation and path analysis for nine quantitative traits in nineteen genotypes of rice bean were studied at the Instructional Farm, Krishi Vigyan Kendra, Mon (Aboi), Nagaland under rainfed conditions during kharif 2015. Maximum phenotypic (PCV) and genotypic (GCV) coefficients of variation were observed in case of number of pods per plant (8.62 and 8.41%) and days to 50% flowering (8.08 and 7.88%). Both heritability and genetic advance are high for number of pods per plant (95.33% and 17.12) and days to 50% flowering (95.68% and 15.32). Days to 50% flowering with grain yield per plant (rg= 0.63 and rp= 0.80) and number of pods per plant with grain yield (rg= 0.89 and rp= 0.86) indicates highly significant and positive correlation at genotypic and phenotypic level. Path analysis revealed that only days to 50% flowering had showed high direct effect and highly significant positive correlation with grain yield per plant (0.848 and rg= 0.781), indicating the importance of selection based on this character to increase grain yield per plant.

Evaluation of genetic diversity in ricebean [Vigna umbellata (Thunb.) Ohwi and Ohashi] germplasm using SSR markers

Genetic improvement mainly depends on the extent of genetic variability present in the population. The molecular marker is a useful tool for assessing genetic variations and resolving cultivar identities. The objective of this study was to evaluate the genetic divergence of 40 germplasm lines of ricebean. Forty-four SSR markers were used in the present study, out of which only seven were found to be polymorphic. The dendrogram based on SSR marker analysis grouped the 40 ricebean genotypes into 2 clusters, where cluster I was the largest with 37 genotypes. STRUCTURE analysis for the estimation of population structure divided 40 genotypes into 4 groups in which P1 group consisted of 5 genotypes, P2 with 23 genotypes, P3 with maximum number of 7 genotypes, whereas, P4 consisted of 5 genotypes. The genetic variation revealed by SSR analysis will be used in the future breeding programme of ricebean for the selection of diverse parents for hybridization.

Antinutritional factors in ricebean, Vigna umbellata Thunb. (Ohwi and Ohashi) against Callosobruchus maculatus F. (Coleoptera: Bruchidae)

To identify some effective and eco-friendly inhibitors of a serious pest of pulse crops, Callosobruchus maculatus, seeds of 10 genotypes of rice bean, Vigna umbellata and mungbean variety, PAU 911 as susceptible check were screened. The different genotypes of rice bean were found to arrest the growth and development of C. maculatus at grub stages in varying levels. To confirm these results, the seeds of different test genotypes were analysed for the presence of three antinutritional factors (tannins, phytic acid and saponins). The amount of tannins, phytic acid and saponins was recorded highest in rice bean genotype LRB 507 (11.12 mg g−1), LRB 482 (32.30 mg g−1) and LRB 535 (4.17 mg g−1), respectively whereas lowest in mungbean variety, PAU 911 (8.24, 13.51 and 1.12 mg g−1, respectively). These antinutritional factors showed a negative correlation with adult emergence, growth index and adult longevity of C. maculatus but positive correlation with development period. Based on the results of the present study, all the rice bean genotypes were identified as resistant to C. maculatus as compared to susceptible check variety, PAU 911. The role of antinutritional factors in relation to C. maculatus infestation is discussed.

Rice bean: nutritional vibrant bean of Himalayan belt (North East India)

Purpose The purpose of this paper was to analyse the present status of the information available on rice bean [Vigna umbellata (Thunb.)] cultivars with respect to its nutritional and functional characteristics. It is one of the non-conventional and under-utilized beans of South and Southeast Asia. In northeastern regions of India, it is an important crop for shifting cultivation or kitchen garden which is consumed as vegetable (tender pod) and pulse. The information gaps filling could be useful for several work proposals and for consumers and cultivators to know the nutritional strength and varied usability of the grain which in-turn can help in its commercialization. Design/methodology/approach The approach to information collection was emphasized on nutritional strength of the grain compared to other beans of Vigna family and the varied usability among the rice bean varieties of the Himalayan Belt. Findings The average carbohydrate, protein, fat, crude fibre and ash content of 75 genotypes of rice bean was found 59.96 ± 2.81, 20.78 ± 2.65, 1.74 ± 1.42, 5.07 ± 1.17 and 4.44 ± 1.03 per cent, respectively. It has high quality protein with all essential amino acid in balance manner. Among the minerals, it contains calcium, iron, zinc and potassium with high bio-availability of calcium (59.8 ± 0.3 per cent). The factors such as flatulence producing saccharides, trypsin inhibitors, polyphenols, phytic acid, saponin and tannins of rice bean were reported to be in the range of 3.28-5.87 per cent, 55.12-163.98 TIU/g, 0.58-1.82 1.88-8.17, 1.2-3.1 and 0.24-1.55 per cent, respectively. The toxic compounds such as hydrogen cyanide (0.09 mg/100 g) and L-3, 4-dihydroxyphenylalanine (0.36 mg/100 g) is lowest in rice bean. The nutritional advantages of rice bean over the other beans of Vigna family were required to emphasize to induce interest among the researchers, producers and consumers. Research limitations/implications In view of the recommended daily requirements with respect of amino acids, vitamin-B and minerals, rice bean could be a major component of the diet to fulfill them. However, the scanty information available on nutritional and functional components of rice bean varieties grown in northeastern India calls for the gap filing research to explore full potential of the bean. Originality/value The information about differences among the northeastern varieties of rice bean available on nutritional functional components essentially required the updating of research data to explore full potential and utility of the bean.

Introgression of mungbean yellow mosaic virus resistance in Vigna mungo (L.)Hepper and purity testing of F1 hybrids using SSRs

The present study was designed to transfer mungbean yellow mosaic virus (MYMV) resistance in urdbean from ricebean. Four MYMV-resistant ricebean genotypes (RBL1, RBL6, RBL35, and RBL50) were hybridized as males with the MYMV-susceptible urdbean line PS 1 using hand emasculation and pollination techniques under field conditions. The results revealed significant differences in the crossability of ricebean genotypes with an urdbean genotype. The highest number of crossed pods was obtained from the interspecific cross PS1 × RBL35. Crossability ranged from 0.6% to 2.89% with an average value of 1.87%. The number of F1 seeds in the crossed pod varied from 1 to 4. Molecular and morphological characterization verified the genetic purity of the developed hybrids. These hybrids exhibited resistance against MYMV infection under natural epiphytotic field conditions. The present study will help to develop improved varieties or lines of urdbean with stable MYMV resistance.

Analysis of simple sequence repeats in rice bean (Vigna umbellata) using an SSR-enriched library

Rice bean (Vigna umbellata Thunb.), a warm-season annual legume, is grown in Asia mainly for dried grain or fodder and plays an important role in human and animal nutrition because the grains are rich in protein and some essential fatty acids and minerals. With the aim of expediting the genetic improvement of rice bean, we initiated a project to develop genomic resources and tools for molecular breeding in this little-known but important crop. Here we report the construction of an SSR-enriched genomic library from DNA extracted from pooled young leaf tissues of 22 rice bean genotypes and developing SSR markers. In 433,562 reads generated by a Roche 454 GS-FLX sequencer, we identified 261,458 SSRs, of which 48.8% were of compound form. Dinucleotide repeats were predominant with an absolute proportion of 81.6%, followed by trinucleotides (17.8%). Other types together accounted for 0.6%. The motif AC/GT accounted for 77.7% of the total, followed by AAG/CTT (14.3%), and all others accounted for 12.0%. Among the flanking sequences, 2928 matched putative genes or gene models in the protein database of Arabidopsis thaliana, corresponding with 608 non-redundant Gene Ontology terms. Of these sequences, 11.2% were involved in cellular components, 24.2% were involved molecular functions, and 64.6% were associated with biological processes. Based on homolog analysis, 1595 flanking sequences were similar to mung bean and 500 to common bean genomic sequences. Comparative mapping was conducted using 350 sequences homologous to both mung bean and common bean sequences. Finally, a set of primer pairs were designed, and a validation test showed that 58 of 220 new primers can be used in rice bean and 53 can be transferred to mung bean. However, only 11 were polymorphic when tested on 32 rice bean varieties. We propose that this study lays the groundwork for developing novel SSR markers and will enhance the mapping of qualitative and quantitative traits and marker-assisted selection in rice bean and other Vigna species.

Co-efficient of variation, heritability, genetic advance and variability for ricebean (Vigna umbellata (Thunb.) genotypes under mid hill conditions of Uttarakhand

The present investigation was carried out to estimate the genetic parameters for ten traits in ricebean genotypes. Fourteen genotypes of ricebean (Vigna umbellata (Thunb.) were collected from different regions of country were evaluated for yield and its components. The study revealed that the phenotypic coefficient of variation (PCV) was higher than genotypic coefficient of variation (GCV) for all traits. The value of PCV and GCV was higher for seed yield/plant, 100 seed weight and number of pods/plant. Heritability values were high for all the traits except leaflet size and pod length. High genetic advance was observed for days to 50% flowering, number of pods and seeds /plant, days to maturity, suggest that scope for improvement of these characters through selection. High heritability coupled with high genetic advance was registered for 50% flowering, number of pods and seeds /plant indicate that the genetic variance for these traits are probably owing to their high additive gene effect and thus there is better scope for improvement of these traits through direct selection. Therefore selection based on these characters will bring the desired improvement in seed yield of ricebean. With respect to mean performance of genotype, PRR-2, PRR-1 and PRR-2011- 1 was found superior among all the genotypes.

The transferability and polymorphism of mung bean SSR markers in rice bean germplasm

Rice bean (Vigna umbellata (Thunb.) Ohwi and Ohashi) is an understudied crop grown on poor soils in East Asia. Since no simple sequence repeat (SSR) markers have been developed for rice bean, our goal was to evaluate genomic SSR markers from mung bean (Vigna radiata L. Wilczek) and to provide basic tools for genetic study of rice bean. A total of 2,540 pairs of newly developed SSR primers from mung bean were tested to determine their transferability and polymorphism in rice bean. The results showed that 787 primers pairs (Vr markers) could be used to successfully amplify rice bean DNA loci. Of these markers, 47 showed reliable banding and polymorphisms among 24 rice bean accessions. These SSR markers were further analyzed using 230 acces- sions from a rice bean core collection held in the Chinese Academy of Agricultural Science: 165 alleles were detected in the accessions, and the number of alleles varied from 2 to 6 with a mean of 3.51 per locus. The PIC values varied from 0.042 to 0.711 and averaged 0.418. Population structure analysis indicat- ed that these 230 rice bean genotypes could be divided into six clusters, somewhat in agreement with the eco- regions across 12 different provinces where rice bean is originally collected. The present study supplies a set of useful group of SSR markers to accelerate the genetic study of rice bean and provide information for breeding program design.