Maximum Inter-cluster Distance Research Articles

Genetic analysis for growth and wood fiber properties in second generation clones of Acacia auriculiformis

Genetic variability of growth, wood density and fibre characters was determined in twenty second-generation clones of Acacia auriculiformis grown at IFGTB- Field Research Station, Neyvli, Tamil Nadu, India. Total volume revealed high phenotypic (29.10 %) and genotypic coefficient of variation (31.30%). Moderate PCV and GCV values were observed for height, fibre lumen diameter, Runkel ratio, slenderness ratio and wood density. The volume and fibre lumen diameter had high heritability 86 and 76 per cent, respectively. Fibre length, Runkel ratio, slenderness ratio and rigidity coefficient showed high heritability coupled with high to moderate genetic advance. Twenty clones was formed into four clusters by D2 analysis. Maximum inter-cluster distance was recorded between cluster II and cluster IV (7.396) and minimum inter-cluster distance was recorded between clusters II and IV (3.364). Higher intra-cluster values were observed in clusters I (4.171) and lower values in cluster III (3.179). Selection of clones based on clusters provides an opportunity for further improvement of growth and wood quality. Key wordsAcacia auriculiformis, Genetic Variability, Diversity, Heritability and Genetic advance

Assessment of genetic divergence through cluster analysis of chilli varieties

Our study on genetic diversity was conducted with six chilli genotypes with inter- and intra-specific cross varieties of the three most popular chilli species (Capsicum annuum L., Capsicum chinense Jacq., and Capsicum frutescens L.). Twelve quantitative characters, viz. plant height (cm), primary branches, secondary branches, number of flowers, number of fruits/plant; dry fruit weight (g), fruit length (cm), fruit diameter (cm), pedicel length (cm), pericarp thickness (mm), seeds/fruit, and seed weight (g), were taken into consideration. The analysis of variance revealed considerable variability among the genotypes for the character studied. Cluster analysis was used for grouping of parental and hybrid chilli genotypes under the study grouped into five clusters. Cluster I had the maximum (12) and clusters IVand V had the minimum number (1) of genotypes. The inter-cluster D2 values ranged between 40.404 and 127.530. The minimum inter-cluster distance was between clusters III and IV (40.404). The maximum inter-cluster distance was observed between clusters II and V (127.53). Diversity pattern and other horticultural performance among the genotypes of new varieties were generated due to the cross between Local Line Mahadev Pramanick and Sukhia bullet and also the cross between Local Line Mahadev Pramanick and Habanero orange (cluster II) as well as single parental variety i.e. Habanero orange. These genotypes were identified as promising varieties with respect to various characters may be taken into consideration as better parents for an efficient hybridization programme of chilli.

Genetic divergence in Indian mustard (Brassica juncea L. Czern. & Coss.

Genetic divergence was carried out in 15 Indian mustard varieties/strains, 4 testers and 60 F1s developed by crossing 15 lines with 4 testers. Based on D2 values between the pair of genotypes, 19 parental lines were grouped into five clusters in E1 (timely sown) & E2 (late sown) condition. In E1, cluster II was the largest having 8 genotypes followed by cluster I and IV with four genotypes. Whereas, in E2 cluster I was largest having 9 genotypes followed by cluster V which had four genotypes. In E1 the intra-cluster distance ranged from 0.00 (cluster V) to 581.64 (cluster IV). Cluster IV and V were the most diverse with inter-cluster distance of 7169.70 followed by cluster II and V (4829.11). Whereas, in E2 the intra-cluster distance ranged from 0.00 (cluster IV) to 296.03 (cluster V). Clusters IV and V were the most diverse with inter-cluster distance of 1894.16. The 60 F1s were grouped into eight clusters in E1 and E2. In E1, the maximum number of genotypes were grouped in clusters I and VI (12) and the intra-cluster distance ranged from 111.59 to 318.07. The maximum inter-cluster distance was observed between cluster IV and VIII (3554.76). Whereas, in E2 maximum number of genotypes grouped in cluster III (15) and intra-cluster distance ranged from 0.00 to 351.31. The maximum inter-cluster distance (D2) was observed between cluster V and VIII (43829.30).

Multivariate Analysis using D2 and Principal Component Analysis in Mung bean [Vigna radiata (L.) Wilczek] for Study of Genetic Diversity

Background: Seventy breeding lines of mung bean were evaluated for 20 different characters and mean values were worked for genetic diversity by Mahalanobis D2 statistic. Methods: The experiments included 70 mung bean breeding lines which were collected from Plant Breeding Unit, Agricultural Research Station, Badnapur. They were grown during Kharif 2016 at experimental research farm Badnapur of Vasantrao Naik Marathwada Krishi Vidyapeeth, Parbhani. The data were recorded for 20 different characters on 10 randomly selected plants. The statistical analysis were done by Mahalanobis D2 statistics.Result: The results of D2 analysis indicated the presence of considerable genetic divergence among these breeding lines. In the present study, inter-cluster distances were worked out considering 20 characters and these distances ranged from 240.96 (between cluster V and cluster VII) to 1080.72 (between cluster V and cluster VIII). The inter-specific derivatives were grouped into eight clusters. The maximum inter-cluster distance was between cluster V and cluster VIII. The maximum inter-cluster distance was between cluster V and cluster VIII (1080.72), followed by cluster II and cluster III (932.25), cluster IV and cluster VIII (910.11), cluster VII and cluster VIII (738.30), cluster I and cluster VIII (732.61), cluster VI and cluster V (660.49) and cluster II and cluster VI (494.93). This suggested that there is wide genetic diversity between these clusters. Based on these studies, crosses can be made between breeding lines of these clusters to obtain desirable results either in transgressive breeding or in heterosis breeding. Cluster VIII and cluster IV showed high mean values for most of the yield contributing traits like100-seed weight, shelling %, harvest index, pod length, primary branches per plant, days to 50% flowering, days to maturity, leaf width and days to shattering. So the lines from cluster IV and cluster VIII can be used for mung bean yield improvement programme.

Evaluation of sunflower (Helianthus annuus L.) genotypes for quantitative traits and character association of seed yield and yield components at Oromia region, Ethiopia

Sunflower is one of the most important oil crops in Ethiopia in terms of edible oil and holds significant promise for improvement and development improved varieties. The present study was initiated to study the genetic diversity and performance of sunflower genotypes that enables to harness its seed yield and oil content improvement by using 25 genotypes including two standard checks namely Russian black and Oissa at Holeta Agricultural research center by using simple lattice design. The genotypes characterized for different agro-morphological traits and oil content. The analyses of variances have revealed highly significant difference among the genotypes for all the characters. The data revealed that sufficient variability was present among sunflower genotypes considered under this study. High Phenotypic coefficient variation, Genotypic coefficient variation and estimates of heritability (broad sense) were obtained for seed yield, oil content, oil yield, and thousand seed weight while the above parameters were found to be less compared to characters. High heritability accompanied with high genetic advance, as per percentages of mean was observed in case of seed yield, oil content, oil yield per plot, harvest index, head diameter and plant height suggesting importance of additive genetic action in the inheritance of these characters. While, high heritability coupled with moderate genetic advance was observed for days to maturity and days to 50% flowering, seed yield per plant, leaf number and reproductive phase. These indicate that the traits were controlled by additive gene action. Days to maturity, oil yield, seed yield per plant, head diameter and reproductive phase revealed positive association and had positive direct effect of seed yield. Based on genetic distance (D2 value), the genotypes under this study were grouped into two clusters indicating wider genetic diversity among the genotypes. Among the two clusters, cluster II represented the largest genotypes (18) followed by cluster I (4) genotypes and cluster S1, S2, and S3 genotypes. The clustering pattern indicated the absence of relationship between genetic diversity and geographical origin of genotypes. The maximum inter-cluster distance was observed between cluster I (D2 = 6.85). Out of the thirteen traits four significant principal components (PCs) exhibited more than 1 Eigen value and showed about 80.2% variability among the genotypes studied. The first PC accounted 41% of the variances that implies greater proportion of variable information explained by PC1. This indicates that any improvement of these characters would result in a substantial increment of seed yield.

Genetic diversity and correlation studies in rice (Oryza sativa L.)

The present investigation consists of 26 germplasm used for the experiment was conducted during Kharif-2019 in Randomized Block Design with three replications at Field Experimentation Centre, Department of Genetics and Plant Breeding, Sam Higginbottom University of Agriculture Technology and Sciences, Prayagraj (Allahabad). The data were recorded on thirteen quantitative characters to study genetic variability, heritability, genetic advance, correlation coefficient, path coefficient and genetic divergence. On the basis of mean performance highest grain yield per plant was exhibited by SHIATS DHAN-2 (38.4 g), followed by SHIATS DHAN-1 (38.0 g), SHIATS DHAN- 3 (37.60 g). Analysis of variance among 26 germplasm showed highly significant differences for all the characters under study indicated the presence of a substantial amount of genetic variability. Higher estimates of GCV and PCV were for higher estimates of GCV and PCV were for Spikelets per panicle followed by tillers and number of panicles. High heritability was recorded for days to maturity followed by Days to flowering 50%. High heritability coupled with high genetic advance is recorded for spikelets per panicle. Correlation study revealed that grain yield per plant showed the high positive significant association for all the characters plant height, flag leaf width, number of tillers, number of panicles, panicle length, biological yield per plant and spikeslets per panicle at both phenotypic and genotypic levels. Path coefficient analysis revealed that plant height, flag leaf width, number of panicles, panicle length, days to maturity, biological yield per hill and harvest index had positive direct effect on yield at phenotypic level for improvement of grain yield in rice. Based on the relative magnitude of D2 values, the genotypes were grouped into seven clusters by Euclidean methods of divergence study. Cluster I consist of a maximum of eight genotypes, followed by cluster II with six genotypes, cluster III with three genotypes, cluster IV with three genotypes, cluster V with two genotypes, cluster VI with one genotype, cluster VII with three genotypes. The maximum inter-cluster distance was observed between cluster VII and V followed by cluster V and IV. Thus, the genotypes from the clusters having maximum inter-cluster distance can be selected and used as parents for hybridization programme to develop desirable lines. Maximum genetic divergence was exhibited by grain yield per hill and test weight contributed to 78.77% of total divergence which is needed to be focused while selecting parents for hybridization programme.

Genetic Divergence Study in Maize (Zea mays L.) Inbred Lines under North Western Himalayan Conditions

Genetic divergence in 50 maize inbreds including five checks was assessed based on some morpho-physiological and yield contributing traits using Mahalanobis D2 statistics. The experiment was carried out in an augmented block design at Maize Research Station, SKUAST-J, Udhampur, J&K during Kharif 2019-20. All the inbreds were grouped into ten clusters based on D2 analysis. Maximum numbers of genotypes (12) were grouped in cluster III whereas cluster X (1) was the smallest. Maximum inter-cluster distance was observed between cluster VIII and cluster IX indicating presence of maximum diversity among the genotypes falling within these clusters. The genotypes in the cluster VIII showed better performances having high shelling percentage (%), grain yield per plot (g), cob length, kernels per row and 1000 kernel weight (g). It is expected that crossing of inbred lines belonging to high-medium D2 values may tend to produce high heterosis for yield. Perusal of the data indicated that moisture percentage contributed maximum of 8.90 per cent whereas, days to 50 % silking contributed the lowest of 0.73 per cent to the total genetic divergence.

Genetic Divergence Studies in Horse gram (Macrotyloma uniflorum Lam.Verdc) for Quantitative Traits using Mahalanobis D2 Analysis

The present study aimed to estimate the nature and magnitude of genetic divergence in 60 horse gram genotypes for ten characters using Mahalanobis D2 analysis. The genotypes were grouped into thirteen clusters. Concerning intracluster distance, the genotypes falling within cluster III (31.51) has maximum divergence. Maximum inter-cluster distance was observed between cluster VIII and XIII (184.05), followed by cluster XI and XIII (170.83). Cluster VIII exhibited a higher mean for hundred seed weight, grain yield per plot and Bhusa yld/plot and cluster VI contained genotypes with the higher mean value for pod length and the number of seeds per pod. Among the yield contributing characters, the traits viz.,grain yield per plot (28.30%) followed by the number of pods per plant (26.21 %) and the number of branches per plant (18.36%) contributes to major genetic divergence.The results indicated that from cluster IV the genotype HA 871-5-67/2 was selected for plant height, from cluster II the genotype Morappur-1 was chosen for the number of branches per plant, from cluster XII the accession HG 102 was selected for the trait number of pods per plant, from cluster VI the genotype T 45 was chosen for pod length and the number of seeds per pod. From cluster VIII the genotypes 12EB and IC 9606 were nominated for hundred seed weight, grain yield per plot and Bhusa yield per plot(g).

Phenotypic Diversity of Ethiopian Coffee (<i>Coffea arabica </i>L.) Accessions Collected from Limmu Coffee Growing Areas Using Multivariate Analysis

Forty seven <i>Coffea arabica</i> L. germplasm accessions collected from Limmu district were field evaluated from 2004/5 to 2013/14 with two commercial check varieties at Agaro Agricultural Research sub center in single plot. The objective of the experiment was to assess the variability among the accessions using quantitative traits. Data for about eight quantitative traits were recorded only once in experimental period, while the yield data were recorded for six consecutive cropping seasons. Cluster, genetic divergence, and principal component analysis were used to assess the variability among the genotypes. The results revealed that average linkage cluster analysis for nine traits grouped the germplasm accessions in to three clusters. The number of accessions per cluster ranged from three in cluster III to 25 in cluster II. The clustering pattern of the coffee accessions revealed that the prevalence of moderate genetic diversity in Limmu coffee for the characters studied. The maximum inter-cluster distance was observed between clusters II and III; whereas the minimum inter-cluster distance was observed between clusters I and II. The study highlighted the possibility of using accessions of the distant clusters as potential candidates for the genetic improvement of Limmu coffee through hybridization. Moreover, the principal component analysis showed that the first four PCs extracted about 82% of the total variance of the 49 coffee germplasm accessions and also confirmed moderate diversity among the germplasm accessions since the entire variation cannot be explained in terms of few PCs. This, in turn, indicates that the involvement of a number of traits in contributing towards the overall diversity.

Genetic divergence for yield contributing characters in F5 families of rice (Oryza sativa L.)

Twenty-one different F5 families derived from eight different crosses involving seven improved parental genotypes of West Bengal were studied for genetic diversity on the basis of yield and its attributing characters. Based on D2 analysis, the 21 families were grouped into 8 clusters. Cluster I consisted maximum of 6 families followed by Cluster II with 4 families. Wilk’s Lambda criterion = 0.7 × 10-7 and V=716.42 with 240 df revealed a highly significant difference among the genotypes for the pooled effects of all the characters. The clusters VII and VIII were mono-familial although there was a common parent. The maximum inter-cluster distance was found between cluster III and IV. Relative contribution of 100-grain weight to the total divergence was highest, followed by plant height, days to 50% flowering and straw yield. &nbsp;

Multivariate Analysis of Phenotypic Diversity of Rice (Oryza sativa L.) Landraces from Lamjung and Tanahun Districts, Nepal

The magnitude and nature of genetic divergence play a vital role in the selection of the desirable landraces for its utilization in the breeding program. A study was carried out with 30 rice landraces at the Institute of Agriculture and Animal Science, Lamjung Campus, during June–November 2018 to determine relation among individuals, estimate the relative contribution of various traits of rice using principal component analysis, and identify the potential parents for hybridization using Mahalanobis distance (D2). The principal component analysis revealed that five among the thirteen principal components were significant (eigenvalue &gt;1) and contributed to 29.96%, 20.26%, 13.56%, 11.68%, and 9.22% of the total variance, respectively. PC1 included the traits that were related mostly to the yield, yield attributing, and grain characteristics. Landraces from Anadi group, Jetho Budo, Jarneli, and Rato Masino performed well in PC1 while landraces such as Mansara, Pakhe Sali, and Aanga performed well in PC2. The landraces were grouped into six clusters where 12 landraces were grouped into cluster I. Cluster analysis showed maximum and minimum intracluster distance in cluster VI (D2 = 35.77) and cluster I (D2 = 18.59), respectively. The maximum intercluster distance was obtained between clusters V and VI (D2 = 40.18) followed by clusters III and VI (D2 = 36.17) and clusters IV and VI (D2 = 35.74). Cluster III showed the highest mean value for grain width, flag leaf breadth, yield, and minimum mean value for plant height while mean values of total grain per panicle, filled grain percentage, and thousand-grain weight were maximum in cluster IV. Mean values of effective tiller and kernel width were found maximum in clusters V and VI, respectively. Landraces from clusters V and VI or clusters III and VI or clusters IV and VI can be used in the hybridization program to develop the superior hybrids by exploiting heterosis in segregating generation.

Estimating genetic divergence in rice (Oryza sativa L.) using D² analysis

Rice is the staple food across Asia, where around half of the world’s poorest people live and hence that necessitates breeding for high yielding genotypes. Genetic diversity present in the germplasm is pre-requisite for crop improvement as it helps in the development of superior recombinants. Knowledge about genetic diversity between the genotype can be utilized for the selection of diverse parents in hybridization programmes. In this study, using Mahalanobis D² statistics twenty four advanced genotypes were grouped into five different clusters based on their level of divergence. The Cluster III displayed the maximum intra-cluster distance with six genotypes followed by cluster II with ten genotypes. The cluster II and IV exhibited the maximum inter-cluster distance. Among the traits, days to 50% flowering contributed the highest towards total divergence.

Genetic diversity analysis in bread wheat (Triticum aestivum L.) under Gangetic Alluvium Zone of West Bengal

Forty-nine genotypes of bread wheat (Triticum aestivum L.) were screened at District farm, AB Block, B.C.K.V., Kalyani,&nbsp;Nadia, West Bengal during Rabi season for two years, i.e. 2015-2016 and 2018-2019 following Randomized Block&nbsp;Design with two replications to study genetic diversity following the Mahalanobis D2 statistics and principal component&nbsp;analysis. The highest contribution towards total divergence was yield plant-1 followed by the number of grains spike-1,&nbsp;plant height, weight of grains spike-1 and the test weight. The maximum inter-cluster distance was observed between&nbsp;cluster IX and I (86.392), followed by clusters VIII and IX (82.829) indicating that the genotypes being represented in&nbsp;these clusters were distantly related. Therefore, any two genotypes selected from these two clusters may be utilized&nbsp;in crossing programs to synthesis potential high yielding genotypes. Principal component analysis (PCA) extracted 5&nbsp;principal components explaining 80% to genetic variation. The PCA suggested that the genotypes are highly diverse.

Evaluation of genetic diversity in Lepidium sativum L. germplasm based on multivariate analysis

Lepidium sativum L. is a fast-growing and underutilized medicinal plant. The Indian system of medicinal and health recognized this plant as a source of several medicinal and nutraceutical molecules. The 94 accessions collected from different eco-geographical region of India were evaluated for two consecutive years to assess the level of genetic variability. The ANOVA revealed considerable variability for all the quantitative traits. The hierarchical clustering grouped all the accessions into 6 clusters. The clustering showed that majority of accessions i.e. 68 (72%) were genetically close as they grouped into three clusters (I, IV, V). The intra-cluster values ranged from 138.89 (cluster I) to 26.92 (cluster IV). The minimum inter-cluster distance was recorded 51.63 (between cluster III and IV), while the maximum inter-cluster distance was 361.02 (between cluster II and VI). The correlation among the traits were found to be of similar magnitude and direction for almost all the traits. The highest and lowest broad sense heritability was recorded for plant height (88.88%) and number of lateral branches (26.98%) respectively in first year, while in second year, the number of silique/plant (97.30%) and date of emergence (4.36%) respectively. The high estimates of genetic advance were noticed for all the traits except plant height, days of maturity and number of silique/plant. Through the present investigation diverse accessions have been identified that could utilized for further genetic improvement of Lepidium sativum.

Studies on genetic divergence (D2) for fruit yield and its related traits in pumpkin (Cucurbita moschata Duch. ex. Poir)

An experiment was conducted at Main Experiment Station of Department of Vegetable Science at Acharya Narendra Deva University of Agriculture and Technology, Kumarganj, Ayodhya (U.P). The experimental material consisted of 28 pumpkin genotypes including three standard checks viz., Arka Chandan, Azad Kaddu and Pusa Vikash was conducted in a Randomized Block Design with three replications. Analysis of variance studies indicated significant differences among all the genotypes for all the characters under study. Genetic diversity was worked out using Mahalanobis D2 statistic. Based on D2 analysis, the genotypes were grouped into 7 distinct non-overlapping clusters. Cluster I, II and III had 6 genotypes in each clusters. Cluster IV, V and VI also had 3 genotypes and cluster VII had presented only one genotype. The maximum intra-cluster distance was in cluster V (139.09) and minimum intra-cluster distance was found for cluster VII (0.00). Clustering pattern revealed that geographical diversity was not associated with genetic diversity of genotypes. The maximum inter-cluster distance was observed between clusters III to cluster VII (503.329), which suggested that members of these two clusters are genetically very diverse to each other. The inter cluster values between cluster I to cluster VII (398.733), V to VII (325.792), II to VII (315.975), V to VI (312.753) and I to V (309.983) were also high. The minimum inter-cluster D2 value was recorded in case of cluster III to cluster IV (174.606). The wider genetic diversity were observed in cluster clusters I to VII, V to VII, II to VII, V to VI and I to V which indicated the potentiality of these diverse genotypes collection for providing basic material for future breeding programmes.

Genetic distance among mungbean germplasm pertaining to grain yield and yield components

Sixty greengram germplasm lines were subjected to multivariate analysis through Mahalanobis’ D2 statistics (Tocher’s method) and 60 genotypes were grouped into nine clusters. Cluster III was the largest with 19 genotypes, followed by cluster I having 17 genotypes, cluster II and VII with eight genotypes, cluster V having 5 genotypes and clusters IV, VI, VIII and IX were solitary clusters. The maximum inter-cluster distance was between cluster VIII and IV, followed by cluster VIII and V. It shows that there is wide genetic diversity between the clusters. On the basis of divergence between clusters, superior F1s or their transgressive segregants can be obtained by crossing between the genotypes belonging to cluster VIII and cluster IV and also between genotypes belonging to cluster VIII and cluster V which are having maximum inter cluster distance between them. Further such genotypes from above clusters which are having better per se are to be considered for hybridization programme.

Study of genetic divergence in rice (Oryza sativa L.) genotypes with high grain zinc using Mahalanobis’ D2 analysis

The present investigation was conducted with twenty-two genotypes of rice during Kharif, 2018 in RBD with three replications in five different locations. The 22 rice genotypes were characterized based on 16 quantitative traits viz., days to first flowering, days to 50 per cent flowering, days to maturity, the total number of effective tillers per plant, plant height (cm), panicle length (cm), the number of spikelets per panicle, the number of grains per panicle, spikelet fertility percentage, grain weight per panicle (g), grain yield per plant (g) , 1000-grain weight (g), grain yield per plot (kg), grain yield per hectare (kg), grain L/B Ratio, grain zinc content (ppm or mg /kg) using Mahalanobis D2 statistic. D2 analysis distributed the 22 genotypes into six clusters, of which cluster I was the largest with 15 genotypes. Cluster II had maximum intra-cluster values of 5.16 and the maximum inter-cluster distance was observed between the clusters III and V (40.51) followed by cluster IV and V (28.39) indicating the importance of the genotypes present in these clusters for exploiting heterosis for the desirable traits of these clusters.

Mapping QTLs underpin nutrition components in aromatic rice germplasm

As rice is an important staple food globally, research for development and enhancement of its nutritional value it is an imperative task. Identification of nutrient enriched rice germplasm and exploiting them for breeding programme is the easiest way to develop better quality rice. In this study, we analyzed 113 aromatic rice germplasm in order to identify quantitative trait loci (QTL) underpinning nutrition components and determined by measuring the normal frequency distribution for Fe, Zn, amylose, and protein content in those rice germplasm. Comparatively, the germplasm Radhuni pagal, Kalobakri, Thakurbhog (26.6 ppm) and Hatisail exhibited the highest mean values for Fe (16.9 ppm), Zn (34.1 ppm), amylose (26.6 ppm) and protein content (11.0 ppm), respectively. Moreover, a significant linear relationship (R2 = 0.693) was observed between Fe and Zn contents. Cluster analysis based on Mahalanobis D2 distances revealed four major clusters of 113 rice germplasm, with cluster III containing a maximum 37 germplasm and a maximum inter-cluster distance between clusters III and IV. The 45 polymorphic SSRs and four trait associations exhibited eight significant quantitative trait loci (QTL) located on eight different chromosomes using composite interval mapping (CIM). The highly significant QTL (variance 7.89%, LOD 2.02) for protein content (QTL.pro.1) was observed on chromosome 1 at 94.9cM position. Also, four QTLs for amylose content were observed with the highly significant QTL.amy.8 located on chromosome 8 exhibiting 7.2% variance with LOD 1.83. Only one QTL (QTL.Fe.9) for Fe content was located on chromosome 9 (LOD 1.24), and two (QTL.Zn.4 and QTL.Zn.5) for Zn on chromosome 4 (LOD 1.71) and 5 (LOD 1.18), respectively. Overall, germplasm from clusters III and IV might offer higher heterotic response with the identified QTLs playing a significant role in any rice biofortification breeding program and released with development of new varieties.

Genetic divergence of blackgram genotypes (Vigna mungo (L.) Hepper)

Divergence analysis was carried out among hundred black gram genotypes using Mahalanobis D2 analysis. Among ten characters studied, seed yield per plant (g) contributes maximum to the genetic diversity (33.31%). Black gram genotypes were grouped into 14 clusters. Among this, cluster I had maximum number of genotypes. Maximum intra-cluster distance was found in cluster II and the maximum inter-cluster distance was observed between cluster IV and XI. Cluster XI (VBG 19-002) showed the highest cluster mean for seed yield per plant (g), the number of branches per plant and the total number of pods. Cluster IV (VBG 18-076) had superior mean for days to 50% flowering, plant height (cm) and pod length (cm). Hence, hybridization of genotypes VBG 18-076 (Cluster IV) and Mash 114 (Cluster XII) with VBG 19-002 (Cluster XI) could give wide range of variability in segregating population.

Studies on genetic diversity for yield, quality and yield attributing traits in cluster bean [Cyamopsis tetragonoloba (L.) Taub.] genotypes

The study was carried out to assess the genetic divergence among 56 cluster bean genotypes using Mahalanobis D2. Fifty-six genotypes were grouped into 8 clusters based on 11 characters. The intra-cluster distances were seen to be lower than the inter-cluster distances. The maximum inter-cluster distance was noticed between cluster VI and VII whereas, inter-cluster D2 value was least between cluster I and V. The maximum intra-cluster distance was observed in cluster IV. Clusters V, VII and VIII had only one genotype each and hence intra-cluster distance was 0.00. The per cent contribution towards genetic diversity was maximum in 100 seed weight (52.08%) followed by the protein content of pods (45.19%). On the basis of inter-cluster distances observed, the genotypes with specific characters can be utilized for the hybridization programme.