Highest Positive Direct Effect Research Articles

Exploring the yield and yield contributing traits variability in dolichos bean (Lablab purpureus): A character association and path analysis approach

An experiment was conducted during 2019–20 and 2020–21 at ICAR-Central Institute for Subtropical Horticulture, Lucknow, Uttar Pradesh to evaluate the magnitude of variability in dolichos bean [Lablab purpureus (L.) Sweet] genotypes for important horticultural traits and their associations. The observed range and mean variations of the studied traits revealed a significant genetic diversity among the genotypes. The narrow gap in the genotypic (GCV) and the phenotypic coefficient of variation (PCV) for delineated characters indicated that they are governed by genetic factors, and environmental factors had little or no impact on the phenotypic expression of these traits. The traits including pod yield, days taken to first flowering, weight of pod, plant height, and pod width, showed positive GCV, indicating the presence of additive genes action. Traits such as pod weight, days taken to first flowering, and pod width displayed high heritability and moderate genetic advance, suggesting that the high heritability of these traits is due to the effects of additive genes and that genetic gain can be expected through the phenotypic selection. The higher genotypic correlations revealed an inherent association between the traits. Therefore, the selection criterion for high yield was proposed based on the strong character association between plant height, number of pods/cluster, pod width, and pod weight. The number of pods/plant, followed by the number of clusters/plant had the highest direct positive effect on yield. Consequently, pod yield may be increased through selection of heavier pods, more clusters/ plant, and more pods/cluster.

Combining ability of Egyptian cotton (Gossypium barbadense L.) reveals genetic potential for improved yield and fiber quality

BackgroundAs the most widely cultivated fiber crop, cotton production depends on hybridization to unlock the yield potential of current varieties. A deep understanding of genetic dissection is crucial for the cultivation of enhanced hybrid plants with desired traits, such as high yield and fine fiber quality. In this study, the general combining ability (GCA) and specific combining ability (SCA) of yield and fiber quality of nine cotton parents (six lines and three testers) and eighteen F1 crosses produced using a line × tester mating design were analyzed.ResultsThe results revealed significant effects of genotypes, parents, crosses, and interactions between parents and crosses for most of the studied traits. Moreover, the effects of both additive and non-additive gene actions played a notably significant role in the inheritance of most of the yield and fiber quality attributes. The F1 hybrids of (Giza 90 × Aust) × Giza 86, Uzbekistan 1 × Giza 97, and Giza 96 × Giza 97 demonstrated superior performance due to their favorable integration of high yield attributes and premium fiber quality characteristics. Path analysis revealed that lint yield has the highest positive direct effect on seed cotton yield, while lint percentage showed the highest negative direct effect on seed cotton yield. Principal component analysis identified specific parents and hybrids associated with higher cotton yield, fiber quality, and other agronomic traits.ConclusionThis study provides insights into identifying potential single- and three-way cross hybrids with superior cotton yield and fiber quality characteristics, laying a foundation for future research on improving fiber quality in cotton.

Correlation and Path Analysis Studies in Mungbean [Vigna radiata (L.) Wilczek] under Arid Environment of Western Rajasthan

Background: Mungbean is an important grain legume crop. It contains a high amount of protein, carbohydrates, vitamins and minerals. The productivity of this crop is still low, hence efforts should be made to improve the yield of mungbean by keeping knowledge about association between seed yield and its components. Thus, the present investigation was aimed to determine the correlation and path coefficient analysis for seed yield and its attributing traits in mungbean. Methods: Seventy-nine diverse genotypes of mungbean were evaluated during Kharif 2017-18 for eleven quantitative traits in randomized block design with three replications at the Experimental farm, Department of Genetics and Plant Breeding, College of Agriculture, Swami Keshwanand Rajasthan Agricultural University, Bikaner, Rajasthan. Result: Significant genotypic differences were observed for all the traits studied indicating a considerable amount of variation among genotypes for all the characters. The seed yield per plant exhibited highly significant and positive correlation with number of pods per plant, biological yield per plant, harvest index, number of seeds per pod and pod length. The characteristics such as biological yield per plant, harvest index, number of pods per plant, pod length, number of seeds per pod, plant height, 100-seed weight and days to 50 per cent flowering had high positive direct effect on seed yield per plant. Therefore, selection based on the traits viz., number of pods per plant, biological yield per plant, harvest index, number of seeds per pod, 100-seed weight and pod length could help in enhancing the seed yield per plant in mungbean.

Assessment of Correlation and Path Analysis for Seed Yield and its Component Characters in Greengram [Vigna radiata (L.) Wilczek

The present study was carried out during Kharif season 2021 at Crop Research Center (C.R.C), Sardar Vallabhbhai Patel University, Meerut. In the present study, twelve yield and yield related parameters have been studied in 25 diverse genotypes of greengram. The mean sum of squares for genotypes were highly significant for all the traits. In this experiment for majority of cases the genotypic correlation coefficient values was higher than the phenotypic values indicating that the phenotypic expression of correlation was influenced by environment. Seed yield/plant had a highly significant and positive correlation both at genotypic and phenotypic level with number of pods/plant, number of seeds/pod, biological yield and harvest index. Days to 50% flowering, days to maturity, plant height, number of branches/plant, number of pods/cluster and 1000 seed weight exhibited a non-significant correlation with seed yield. In this investigation seed yield per plant was dependent variable and rest of the characters were independent variables. Genotypic and phenotypic path coefficient analysis of seed yield/plant and its component attributes showed that highest positive direct effect towards seed yield/plant was observed by biological yield, harvest index, number of seeds/pod, number of pods/plant, days to 50% flowering, pod length, days to maturity and plant height. Seed yield/ plant could be improved by selection based on these traits.

Path and Genetic Divergence Analysis of Mustard [Brassica juncea (L.) Czern & Coss.] Genotypes

The present investigation consisting of seeds of 72 genotypes with 3 check varieties (Varuna, Kranti, NDR-8501) were used for experimentation under Augmented Block Design in Indian mustard germplasm/genotypes was carried out during 2019-20 on the Student Instructional Farm Acharya Narendra Deva University of Agriculture & Technology Kumarganj Ayodhya (U.P.) India. The characters studies were Days to 50 % flowering, Days to maturity, Plant height (cm), Number of primary branches/plants, Number of secondary branches/plants, Length of main raceme (cm), Number of silique in main raceme, Number of seeds/siliquae, 1000-seed weight (g) and Seed yield/plant (g). The highest positive direct effect on seed yield per plant exhibited by 1000 seed weight (0.2512) followed by length of main raceme (0.2189), the highest positive indirect effect on seed yield per plant was exhibited length on main raceme (0.0477) via seed pre-silique fallowed by the number of siliquae on main raceme (0.0332) via secondary branches per plant. The maximum intra-cluster distance was estimated in case of Cluster VI (2.652) followed by cluster I (2.520), Cluster IV (2.352), cluster III (2.329), cluster VIII (2.148). The highest inter-cluster distance was observed between cluster IV and VI (4.417) followed by cluster III and VI (4.270), VI and VIII (4.251), cluster I and VII (4.156). The maximum cluster mean was found in cluster I (9.21) for seed yield per plant followed by cluster III (8.67) and cluster VII (8.50).

EXPLORING THE RELATIONSHIP BETWEEN PLANT HEIGHT AND YIELD-CONTRIBUTING ATTRIBUTES OF WHEAT IN DROUGHT CONDITIONS

Plant height is the most dynamic yield-affecting trait which has strong genetic and phenological associations with yield performance in wheat. The objective of the study was to explore the effect of plant height on spike yield by investigating the interrelationship between height and yield components of ninety wheat genotypes under a drought environment. Different statistical procedures including correlation, regression, path coefficient, principle component, biplot, and cluster analysis were performed to dissect the associative role of height and yield components in setting the yield potential of wheat plants. High positive correlation and direct effects are seen for spike yield from seed weight (r = 0.73) and seed number (r = 0.60) with a participatory contribution of 58% and 40%, respectively. But plant height is negatively associated with thousand seed weight (-0.22*) and spike yield (-0.15) in such a way that each additional unit (1cm) of height reduces 0.11 g thousand seed weight and 0.06 g spike yield due to negative regression. PC1 and PC2 associate height and yield components respectively and both types of traits moderately oppose each other for simultaneous improvement. Highly tall and short plants were observed with low yield potential under water-limited resources due to strong negative effects either on seed weight or number. An increase in height favors seed number but reduces enough seed weight to cause comparative losses. Intelligent allocation of plant resources to height or spike defines the plant yield potential. Plants with moderate height ranging from 74-83 cm were seen with the best yield potential among five different classes of height. Genotypes HM729, HM829, and HM644 belonged to this class and their better yield potential was due to the balance ratio of seed weight and number. This work would help direct our breeding programs for the improvement of the height-oriented yield potential of wheat.

Correlation and Path Analysis for Agronomic and Processing Quality Traits of Potato (<i>Solanum tuberosum</i> L.) at Holetta, Central Ethiopia

Potato is the third most important food crop in terms of consumption in the world after rice and wheat. It is a nutrient-rich vegetable with just a small amount of fat and contains 16% carbohydrates, 2% proteins, 1% minerals, and 0.6% dietary fiber. The literature on path and correlation analysis and its application as a potato breeding tool is limited in comparison to its significance for processing purpose and the knowledge it adds for upcoming breeding work. The objective of this study was to determine the relation among tuber yield and processing quality traits of potato using correlation and path coefficient analysis. This experiment was conducted at Holetta Agricultural research Centre, Ethiopia during the main crop season of 2017. The experiment was laid out in randomized complete block design (RCBD) with three replications using 24 potato genotypes. Strong positive and significant correlation were found between total tuber yield and marketable tuber yield (r=0.98) at both genotypic and phenotypic levels. Stronger positive correlations were found between dry matter content and starch content (r= 1) and specific gravity (r=1). Path coefficient analysis of tuber yield and its components shows that dry matter content and marketable tuber yield exerted positive highest direct influence on total tuber yield. Specific gravity of tuber had high positive direct effect on dry matter content. So, to increase the performance of these traits for tuber yield and processing quality traits path analysis can be used. As a conclusion, most of the traits had positive correlations and direct effects with total tuber yield and dry matter content at phenotypic and genotypic levels. Therefore, those traits had practical importance in selection of potato genotypes for high total tuber yield and processing purpose.

Genetic association analysis in advance tomato (Solanum lycopersicum L.) lines for horticultural and yield contributing traits

Twenty-two tomato (Solanum lycopersicum L.) genotypes were examined for correlation and path analysis in the randomized block design under open field conditions. Total fruit yield showed a significant positive correlation with the number of fruits per plant, average fruit weight, lycopene content, and percent seedling survival in the field at both the genotypic and phenotypic levels. A strong correlation between these characters revealed that selection based on these characters would consequently improve the total fruit yield. Path analysis showed that the number of fruits per plant, average fruit weight, percent seedling survival in the nursery, and number of locules per fruit exhibited high positive direct phenotypic effects on total fruit yield, whereas the number of fruits per plant, average fruit weight, percent seedling survival in the field, and pollen viability had very high positive direct genotypic effects. Therefore, to increase the yield, it would be profitable to prioritize these traits in the selection program.

Elucidation of Genetic Variability for Seed Yield and Its Component Traits, along with Association Studies in pigeonpea [Cajanus cajan (L.) Millspaugh.

The experimental material consisted of fifty-five pigeonpea genotypes sown in Randomized Block Design (RBD) with three replications during the kharif, 2020-2021 crop seasons at the N. E. B. Crop Research Centre of G. B. Pant University of Agriculture and Technology, Pantnagar, Uttarakhand. The components of genetic variance, correlation, and path coefficient were estimated for seed yield and its component by using fifty five pigeonpea genotypes. The highest PCV (> 20%) was recorded for characters, viz. number of secondary branches per plant (62.34%), number of primary branches per plant (37.65%), number of pods per plant (33.00 %), and seed yield per plant (31.84%), and lowest estimates (< 10%) of PCV were found for days to 50% flowering (9.45%) and days to maturity (5.74%). The high estimates of GCV (> 20%) were recorded for traits viz., number of secondary branches (42.16%), number of pods per plant (32.65 %), and seed yield/plant (30.54%), and lowest estimates of GCV were (<10%) for days to 50% flowering (9.43%) and days to maturity (5.71%) number of seeds per pod (5.28 %) and 100-seed weight (9.51 %). The number of pods per plant, (0.858) had high positive direct effects on the seed yield per plant along with a positive and significant correlation (rp=0.77). Based on the present investigation, it is evident that delving into genetic variability, correlations, and path analyses provides a more effective approach for selection of superior cultivars for yield and related traits.

Mean performances, character associations and multi-environmental evaluation of chilli landraces in north western Himalayas

Even though many varieties have been recommended across agro-climate zones of Himachal Pradesh, yet the information on stability is lacking in this State. Hence, the present investigation was carried out to identify high yielding stable genotypes among various pre-adapted landraces. The material consists of 20 chilli landraces including check i.e. DKC-8. The experiment was laid out in a RCBD. The data were recorded and analyzed to work out mean performances and the inferences were drawn for parameters of variability, correlation coefficients, path coefficients and stability analysis. As per mean performances, CS7 and CS9 were earliest in flowering, CS13 is earliest in days to ripe maturity, CS10 had highest plant height and CS9 had highest average fruit weight and ripe fruit yield plant−1. High PCV and GCV were recorded for ripe fruit yield plant−1. Heritability and genetic advance were recorded maximum for plant height in summer seasons and were recorded maximum for number of ripe fruits plant−1 in winter season. Correlation coefficients showed that number of ripe fruits plant−1 and average ripe fruit weight were positively and significantly correlated with ripe fruit yield plant−1. Path coefficient analysis in summer and winter seasons showed that average ripe fruit weight had the highest positive direct effect on ripe fruit yield plant−1. The pooled data over environments were analyzed to estimate the interaction effects between genotypes × environment. The mean sum of squares due to genotypes, environments and genotypes × environment interaction were significant for all the characteristics. CS1, CS3, CS6, CS10, CS13, CS15 were adapted to all environments, CS7 and CS9 were specifically adapted to favourable environment and CS2 was specifically adapted to unfavorable environment for 50% flowering, landraces CS1, CS2 and CS3were well adapted to all environments for ripe maturity whereas landraces CS6, CS10 and CS19 were well adapted to all environment for number of ripe fruit and ripe fruit yield.

Genetic Evaluation of Recombinant Inbred Lines of Rice Derived from Swarna-Sub1 x AC 20431B for Yield Related Traits

Submergence is the third most important abiotic stress hugely affecting yield and productivity in rice. There are many wild varieties and landraces available which are tolerant to submergence stress. These genotypes can be utilized as donors in different breeding programs. The population derived from such germplasms are subjected to genetic evaluation for yield and yield related attributes for development of lines that are high yielding as well as tolerant to submergence. The present investigation was executed in 120 Recombinant Inbred Lines (RIL) population (F10) derived from Swarna-Sub1 x AC 20431B along with four land races and Swarna-Sub1 to elucidate the association existing between yield and yield attributing characters. Apart from this, Correlation and path analysis was also employed to study direct and indirect effect on grain yield. Observations for agro-morphological traits such as days to 50% flowering, plant height, panicle length, total number of tillers, number of effective tillers per plant, number of filled grains and Spikelet fertility, test weight, grain yield per plant, biomass per plant and harvest index were recorded and analyzed for various variability parameters. Correlation and path coefficient analysis were also carried out. High heritability and genetic advance values were observed for days to 50% flowering, plant height, panicle length, total number of tillers per plant, effective tillers per plant, filled grains per panicle, spikelet fertility, test weight, grain yield and biomass per plant. Among all the characters; filled grains per panicle, biomass and harvest index per plant showed significant correlation with grain yield. Effective number of tillers per plant has the highest positive direct effect on grain yield.

Association studies for yield and yield components in lucerne (Medicago sativa L.) genotypes.

An investigation was carried out to evaluate seventy lucerne ( L.) genotypes during 2020-Medicago sativarabi 21 at SRRS, IGFRI, Dharwad to determine the character association of ten morphological traits to improve the fodder yield. Analysis of variance revealed significant differences between the genotypes for all the traits studied. Correlation analysis revealed that dry fodder yield, plant height, number of branches per plant were significantly and positively associated at genotypic as well as phenotypic level with green fodder yield. Inter-correlation study revealed that a positive and significant association was found among plant height, number of branches per plant and dry fodder yield. The leaf to stem ratio, on the other hand, was negatively associated with green fodder yield. The results of path analysis revealed that dry fodder yield had the highest positive direct effect on green fodder yield, followed by plant height and number of branches per plant. While plant height and number of branches per plant contributed indirectly via dry fodder yield for green fodder yield.The study indicated that these characters would enhance the effectiveness of selection for higher fodder yield in lucerne

Variability, character association and genetic divergence studies in cowpea [Vigna unguiculata (I.)Walp] genotypes

The present experiment comprised of 46 cowpea genotypes to estimate genetic variability, interrelation among 13 quantitative characters and genetic divergence during 2020. High heritability coupled with highKharifgenetic advance as of mean was observed for the characters , seed yield per plant, number of per centviz.clusters per plant, number of pods per plant, plant height, days to 50% flowering and days to maturity. High phenotypic and genotypic coefficient of variation, heritability and high genetic advance as of mean per cent(GAM) were observed in seed yield per plant, number of clusters per plant, number of pods per plant and plant height. Seed yield per plant was found positively and significantly correlated with pods per plant, seeds per pod, pods per cluster, pod length and 100 seed weight. Path analysis revealed that number of seeds per pod, number of pods per plant and 100 seed weight would be selected as important towards seed yield charactersas they showed a high positive direct effect on seed yield. D analysis revealed that all the genotypes were 2grouped into seven distinct clusters. Cluster V had the maximum intra-cluster distance. The crossing among the genotypes of clusters V and VII, II and V, III and VI would result in novel recombinants as they showed high inter-cluster distance. Increased contribution to the divergence was found for the characters like plant height, seed yield per plant, number of clusters per plant and days to 50% flowering. Cluster V was found to be best performing for agronomic characters, followed by Cluster VI and Cluster III. Cluster II was best performing for nutritional value and earliness

Genetic Diversity and Association of Yield-Related Traits in Taro (Colocasia esculenta (L.) Schott) Sourced from Different Agroecological Origins of Nigeria

Taro’s production is characterized by low productivity due to a lack of sufficient improved cultivars suited to the different growing areas coupled with biotic and abiotic stresses. The first step in plant breeding program is to examine and quantify variations for traits of interest in a given set of genotypes so those variations can be exploited in breeding programmes. One hundred taro accessions were evaluated for 16 quantitative traits in a simple lattice design with the objective of estimating variability and determine and quantify association of characters with yield. Multienvironment trial analysis combined over seasons showed highly significant differences among taro accessions for several traits. Yield per plant showed a strong, positive, and highly significant genotypic correlation with plant height (0.99), leaf area (0.82), corm weight (0.99), and cormel weight (0.99). Genotypic path coefficient analysis showed plant height (1.49), leaf area (0.97), corm weight (0.76), and cormel weight (0.21) exerted a high positive direct effect on yield per plant indicating true relationship between the characters. Accessions EBNFC054, EBNFC045, EBNFC100, EBNFC046, EBNFC032, EBNFC075, EBNFC084, EBNFC057, and EBNFC037 were superior and could be promoted to field evaluation. This assessment of variability and associations can assist breeders to tap the potential of the genotypes for certain traits and identify major traits that could be used as a basis for the selection of superior taro genotypes.

Exploring Genetic Variability, Correlation and Path Analysis in Fenugreek (Trigonella foenum-graecum L.) for Crop Improvement

The present investigation has been carried out at Agricultural Research Station, Mandor, Jodhpur during month of Rabi season (October, 2016–April, 2017) to evaluate 35 genotypes of fenugreek to assess extent of genetic variability, heritability, genetic advance with correlation and path coefficient for yield and its contributing characters. The material was planted in Randomized Block Design with three replications and observations were recorded on individual plant basis. Analysis of variance recorded significant between genotypes for the characters studies. The genotypic and phenotypic coefficient of variation was higher for seed yield per plant (g). High heritability (broad sense) coupled with high genetic advance as percentage of mean was observed for branches per plant, no. of pods per plant, pod length (cm), seeds per pod, test weight (g) and seed yield per plant (g). The correlation analysis at genotypic and phenotypic level, seed yield per plant was positively significant correlated with branches per plant, number of pods per plant, test weight, harvest index, days to 50% flowering, pod length and seeds per pod, but except days to maturity at phenotype level which was correlated with negative significance. Path coefficient analysis suggested that the highest positive direct effect on grain yield per plant was exerted by harvest index (%) followed by seeds per pod, test weight, days to 50% flowering, plant height and branches per plant. Number of pods per plant, pod length (cm) and days to maturity contributed considerable negative direct effect on grain yield per plant.

Character Association and Path Co-efficient Analysis Among Inbred Lines of Pearl Millet (Pennisetum glaucum (L.) R. BR.)

A field experiment with 70 pearl millet inbred lines was carried out for analysis of character association and path coefficient for 21 metric traits. A perusal of character association indicated highly significant positive association of panicle weight, green fodder yield plant-1, dry fodder yield plant-1, number of productive tillers plant-1, spike girth, plant height, leaf blade length, number of nodes plant-1, spike length, harvest index, threshing percentage, leaf blade width and specific leaf area at 45 DAS with grain yield plant-1 as well as among themselves at both phenotypic and genotypic levels. Path coefficient analysis indicated that kernel yield plant-1 exhibited high positive direct effect on panicle weight followed by threshing percentage and green fodder yield plant-1. Critical analysis of results obtained from character association and path analysis indicated that grain yield plant-1 had strong positive association with panicle weight which also had high magnitude of positive direct effect. This reveals the importance of this component trait in selection of superior genotypes for higher yield in genotypes of pearl millet.

Genetic analysis of zinc rich landraces for yield, quality and nutritional traits in rice (Oryza sativa L.)

Aim: To study genetic variability, correlation, path and Principal Component Analysis (PCA) in a set of 100 zinc rich rice landraces along with four checks. Methodology: The study was carried out at the Regional Agricultural Research Station (RARS), Maruteru, during Rabi season, 2020-2021 in an Augmented Randomized Block Design. Results: Grain yield per plant, grains per panicle, productive tillers m-2 and test weight showed moderate genotypic coefficient of variation (GCV) and phenotypic coefficient of variation (PCV) coupled with high heritability and genetic advance as per cent mean. These traits also had positive and significant association coupled with high positive direct effect on grain yield per plant. They also contributed maximum variance to the total variability indicating the effectiveness of direct phenotypic selection for these traits for improving the grain yield per plant. Further, cluster analysis grouped the zinc rich rice landraces along with checks into three clusters. Cluster II had the highest genotypes (42), while Cluster I had 32 genotypes and Cluster III consisted of 30 zinc rich landraces along with three check varieties. Interpretation: Grains per panicle, productive tillers and test weight were identified as effective selection criteria for the improvement of grain yield towards development of high yielding zinc-rich rice varieties to curtail micronutrient malnutrition in areas with rice as staple food. Key words: Cluster analysis, Landraces, Oryza sativa, Path analysis, PCA, Zinc

Modeling the facets of burnout in Lisbon airport border officers using PLSc-SEM estimator

Border officers experience stressful moments during the working day at the border point at Lisbon airport (Portugal) that can lead to “emotional exhaustion,” which is the core component of burnout, and relates with “cognitive fatigue (weariness)” and “physical fatigue.” These theoretical concepts cannot be measured (or observed) directly by what are considered latent variables/constructs that are available in Shirom-Melamed Burnout Measure (SMBM). These constructs are, however, operationalized by the questions available in the SMBM, which correspond to observed variables (or manifest variables) expressed in an ordinal scale of seven categories. This questionnaire, reliable and internationally validated, was used in our research and considering the specialized literature, we proposed a hypothetical structural path model that expresses a priori perceptions about the causal relationships between the mentioned latent constructs, where “physical fatigue” is the target construct. A reflective model was estimated based on the sample of primary data and using a Variance-Covariance estimator of Structural Equations Modeling (VB-SEM), the consistent Partial Least Squares (PLSc), that corrects for bias to consistently estimate SEM’s with common factors. The results obtained allow a better understanding of the profile and characteristics of Portuguese border officers who work at Lisbon airport, as well as reveal that the latent exogenous construct “emotional exhaustion” has a high positive direct effect on the “cognitive fatigue,” and through this latter (mediator construct), an indirect effect on the endogenous construct “physical fatigue.” In turn, “cognitive fatigue” has the greatest positive direct effect on “physical fatigue.” The biggest difference identified was between the direct effect of “Emotional exhaustion” on “Physical fatigue,” which is higher for workers with more years of service, as expected. However, the multigroup analysis (using the nonparametric Permutation test) showed that this difference was not statistically significant.

Genetic Variability, Correlation and Path Coefficient Analysis of Ash Gourd (Benincasa hispida (Thunb.) Cogn.) Genotypes

The present investigation was carried out during kharif season, 2018-2019 on 37 genotypes of ash gourd in Randomized Block Design to study the genetic variability, heritability, genetic advances, correlation and path coefficient. Results revealed high genotypic coefficient of variation (GCV) and phenotypic coefficient of variation (PCV) for seediness (44.197 and 44.09), fruit diameter (36.41 and 36.26), average fruits weight (32.308 and 32.27), number of lobes (21.73 and 21.63), peduncle length (25.72 and 25.651), petiole length (22.25 and 22.02), fruit length (25.82 and 25.68), seed width (24.84 and 24.62), number of fruit per plant (21.93 and 21.81), nodes at which first female flower appears (28.54 and 28.48), yield per plant (25.35 and 25.11) and yield per hectare (25.35 and 25.11), respectively. Whereas, high heritability (h2) coupled with genetic advance over mean (GAM) was registered highest in seediness (99.52% and 90.61%) followed by fruit diameter (99.23% and 74.41%), fruit length (98.87% and 52.60%), respectively. Fruit yield per plant showed highly significant positive phenotypic and genotypic correlation coefficients with avg fruit weight (0.708 and 0.709), vine length (0.359 and 0.368), fruit diameter (0.304 and 0.307), seed width (0.337 and 0.342), crop duration (0.370 and 0.356) and cotyledon length (0.295 and 0.305), respectively. The highest positive direct effects on fruit yield was exerted by average fruit weight (1.034) followed by number of fruit/plant (0.738) and vine length (0.062) whereas number of lobes (-0.087) shown highest negative direct effect followed by ovary length (-0.062) and cotyledon width (-0.059).

Morphological Variability and Molecular Diversity in Blackgram (Vigna mungo (L.) Hepper) Genotypes Using SSR Markers

A study on the Morphological variability of 25 Blackgram genotypes was carried out in which molecular diversity of 15 genotypes of Blackgram was studied by using 8 SSR markers. The GCV was lower than PCV for all traits, however, there was narrow difference in PCV and GCV, indicating the effect of environment in lesser frequency. The high seed yield was recorded in the genotypes PLU-429(8.06gm) followed by PL-416(7.37gm) and VBN-8(7.29gm). Among all the factors PC 1 to PC 8, the PC 1 (40.610) accounted maximum proportion of variability in the set of all variables. Association studies revealed that there was high and significant positive amount of genotypic as well as phenotypic correlation coefficient for traits viz., primary branches per plant, number of clusters per plant, number of pods per plant, harvest index. Path analysis revealed high positive direct effect was contributed by primary branches per plant, number of clusters per plant, number of pods per plant, harvest index both at genotypic and phenotypic levels. The Polymorphism information content PIC values of 8 SSR markers valued from 31 percent to 71 percent with mean of 51 percent. BG 18 exhibited highest PIC 71 percent and highest heterozygosity of 62 percent. As per Dissimilarity coefficient, 15 genotypes are grouped into five clusters, Cluster II & V has highest 4 genotypes while in compare with Cluster I, III & IV. SSR marker BG18 has highest number of alleles 5. Shannon’s information index(I) ranged from 1.465 for BG18 to 0.611 for BG07. Fixation index is ranged from 1.000 to -0.111 with mean 0.696. SSRs with high polymorphism information content successfully assisted in the differentiation of genotypes in this study.