Phenotypic Coefficient Of Variation Research Articles

Variability and divergence studies on rice genotypes for micronutrient potential and its utility in biofortification

Rice is the staple food crop for more than half of the world population. Thus, rice varieties enriched with various micronutrients qualifies as a better alternative to combat micronutrient deficiency. The present investigation was undertaken to study the variability, heritability and genetic divergence for grain characters especially grain Zinc (Zn) content and grain Iron (Fe) content in 30 genotypes of rice. Among the 30 genotypes that were under investigation, the Phenotypic Coefficient of Variation (PCV) values were found to be higher than that of Genotypic Coefficient of Variation (GCV) values for all the traits. High heritability (>60%) was observed for all the studied traits. Days to 50% flowering showed highest heritability (99.1%) followed by test weight (94.8%) and grain Fe content (94.8%). The genetic advance as percent of mean ranged between medium (10%-20%) to high (>20%) with grain yield per plant showing the highest GAM (40.84%) followed by test weight (38.56%) and grain Zn content (33.73%). These 30 genotypes were assigned into groups of 11 clusters using Tocher’s method. Cluster I comprised of the most number of genotypes with 18 genotypes followed by Cluster V with 3 genotypes while the remaining 9 clusters were monogenotypic. Days to 50% flowering was found to have the highest contribution towards genetic divergence. These findings indicated that the genotypes under study have sufficient trait variability and varietal diversity which could be exploited in crop improvement programmes aimed at developing Zinc (Zn) and Iron (Fe) biofortified varieties.

Identification of Newer Stable Genetic Sources for High Grain Number per Panicle and Understanding the Gene Action for Important Panicle Traits in Rice

Rice is an important food crop extensively cultivated worldwide, and rice's grain yield should be improved to meet future food demand. Grain number per panicle is the main trait that determines the grain yield in rice, and other panicle-related traits influence the grain number. To study the genetic diversity, 50 diverse Indian-origin germplasm were evaluated for grain number per panicle and other panicle traits for two consecutive seasons (Rabi 2019 and Kharif 2020). The maximum genotypic and phenotypic coefficient of variation was obtained for the number of spikelets and filled grains per panicle. The genotypes were grouped into eight clusters with Mahalanobis' D2 analysis and six groups using Principal component analysis. Based on, per se, performance for grain number per panicle and genetic distances, six parents were selected and subjected to full diallel mating. The genotypes CB12132, IET 28749, and BPT 5204 were the best general combiners for the number of filled grains per panicle and other panicle branching traits, viz., the number of primary and secondary branches per panicle. The hybrid BPT 5204 × CB 12132 identified as the best specific combination for most of the studied panicle traits. The additive gene effects were high for the number of filled grains per panicle, the number of primary branches, and secondary branches, whereas non-additive gene action was high for the number of productive tillers and grain yield per plant. The information obtained from this study will be useful in rice breeding programs to improve panicle traits, especially the grain number, which would result in higher grain yield.

Study of genetic variability, heritability, and genetic advance for yield-related traits in tomato (Solanum lycopersicon MILL.).

Tomato is one of the most significant vegetable crops, which provides several important dietary components. Pakistan has a significant low tomato yield compared to other countries because of low genetic diversity and the absence of improved cultivars. The present study aimed to investigate the genetic variability, heritability, and genetic advance for yield and yield-related traits in tomato. For this purpose, eight tomato parents and their 15 crosses or hybrids were evaluated to study the relevant traits. Significant variation was observed for all studied traits. Higher values of the genotypic coefficient of variability (GCV) and phenotypic coefficient of variability (PCV) were recorded for yield per plant (YP) (kg) (37.62% and 37.79%), as well as the number of fruits per cluster (NFRC) (31.52% and 31.71%), number of flowers per cluster (24.63 and 24.67), and single fruit weight (g) (23.49 and 23.53), which indicated that the selection for these traits would be fruitful. Higher heritability (h2) estimates were observed for the number of flowers per cluster (NFC) (0.99%), single fruit weight (SFW) (g) (0.99%), and yield per plant (YP) (kg) (0.99%). Single fruit weight (SFW) (g) exhibited higher values for all components of variability. High genetic advance as a % of the mean (GAM) coupled with higher heritability (h2) was noted for the yield per plant (YP) (kg) (52.58%) and the number of fruits per cluster (NFRC) (43.91). NFRC and SFW (g) had a highly significant correlation with YP (kg), while FSPC had a significant positive association with YP (kg), and these traits can be selected to enhance YP (kg). Among the 15 hybrids, Nagina × Continental, Pakit × Continental, and Roma × BSX-935 were selected as high-yielding hybrids for further evaluation and analysis. These findings revealed that the best performing hybrids could be used to enhance seed production and to develop high-yielding varieties. The parents could be further tested to develop hybrids suitable for changing climatic conditions. The selection of YP (kg), SFW (g), NFC, and NFRC would be ideal for selecting the best hybrids.

Characterization of wheat genotypes for terminal heat stress tolerance in Bangladesh

This study was aimed to determine the types and levels of variability, heritability, genetic progress, relationships between yield and the features that contribute to it, and some key indicators of terminal heat stress tolerance. Twenty different wheat genotypes were planted in the fields over the course of six different treatments spaced 10 days interval following a Randomized Complete Block Design (RCBD) with three replications. A high degree of significant variation was observed for all the characters studied. Estimates of the genotypic coefficient of variation (GCV) and phenotypic coefficient of variation (PCV) revealed that the phenotypic coefficient of variation was higher than the genotypic coefficient of variation, which indicates a large effect of environment on the expression of the characters studied. The highest estimates of PCV and GCV were observed for grain yield/plant followed by the number of tillers/plant. Heritability estimates revealed that characters like pollen fertility and sterility exhibited the highest heritability followed by days to maturity. The genetic advance was higher for grains/plants followed by plant height. Grain yield showed significant and positive phenotypic and genotypic correlations with grains/plant and 100-grain weight. Phenotypic path analysis revealed a significant direct positive effect of 100-grain weight on grain yield. Principal component analysis (PCA) revealed that the first five components having greater than one Eigenvalue contributed to 83.41% variability. The heat stress tolerance indices revealed that Bijoy and BARI Gom-25 had the lowest tolerance index (TOL), stress susceptibility index (SSI) values and highest yield susceptibility index (YSI) values which show more tolerance and less susceptibility to terminal heat stress and produce moderate grain yield under terminal heat stress. Balaka and Shughat had the highest mean productivity (MP), geometric mean productivity (GMP), and stress tolerance index (STI) values and produce high yields under terminal heat stress conditions.

Variability studies in Valan kakri (Cucumis sativus var. utilissimus L.) germplasm

Valan kakri is an underexploited vegetable and has great potential for genetic improvement through systematic approach. In this study, variability parameters were evaluated in 30 genotypes of Valan kakri collected from different villages across Udaipur during September 2019 and morphological studies were done at Rajasthan College of Agriculture, Udaipur. The genotypic coefficient of variation (GCV) and phenotypic coefficient of variation (PCV) were highest for fruit length (34.48%, 35.43%) followed by fruit weight (61.64 % and 62.04). Estimates for heritability (Broad sense) ranged from 69.70% for seed cavity breadth to 99.24% for acidity of fruit. Traits like fruit length, fruit weight, seed cavity length, acidity of fruit, ascorbic acid content had high GCV, PCV and heritability along with high genetic advance as percentage of mean. Therefore, selection can be effective for these traits in crop improvement programme.

Genetic Diversity, Heritability, Genetic Advance of Growth and Yield Traits of Some Okra (Abelmoschus Esculentus L. Moench) Accessions

Genetic improvement of okra for yield is significant to overcome the low genetic potential of the existing varieties and environmental factors which are the major constraints to okra yield. This study was carried out to understand the genetic nature of yield and its components on which selection can be made. The seed of each accession was sown in a plot laid out in randomised complete block design with three replications. Data were collected on fifteen agronomic characters and analysed. The magnitude of phenotypic coefficient of variation (PCV) and genotypic coefficient of variation (GCV) were highest for number of pods and lowest for number of days to germination respectively. The PCV was moderately higher than GCV in most of the traits studied, which indicated that environment played a little role in the expression of these traits. Low heritability was recorded for number of leaves and number of branches which indicated more influence of environmental effect, which may be due to the presence of non-additive gene action in the expression of the traits. High heritability and high genetic advance as percent of mean were recorded for plant height at flowering, days to 50% flowering, plant height at maturity, internode length, number of pods and days to maturity, indicating that these traits were less influenced by environment and presence of additive gene action. NGB00378A, NGB00299, NGB00304 and NGB00302 had higher fruit yields; flowered earlier, had longer harvesting period. Therefore, selection can be made on these for further improvement of this crop.

Genetic variability and divergence in okra (Abelmoschus esculentus)

An experiment comprising of 10 genotypes of okra {Abelmoschus esculentus (L) Moench} sown in RBD with three replications was conducted during rainy season of 2019 and 2020 at Vegetable Research Farm, BUAT Banda. The genotypic coefficient of variation (GCV) and phenotypic coefficient of variation (PCV) were highest for days to 50% germination and lowest for first flower, days to 50% flower, days to maturity, fruit length, fruit diameter, number of seeds/fruit, fruit yield/plant, fruit yield/plot and fruit yield (q/ha). The heritability estimates were high for days to 50% germination, average fruit weight, number of fruits/plant, fruit yield/ plant and fruit yield (q/ha) indicating that selection based on phenotypic performance would be more operative. The high heritability coupled with high GAM was observed for days to 50% germination, average fruit weight and number of fruits/plant, indicating that additive gene effect was more important. Based on D2 analysis, 19 genotypes were grouped into six clusters. The cluster I had seven genotypes followed by cluster II and III with six and three genotypes respectively, while and remaining clusters were monogenotypic. The cluster II recorded maximum intra cluster distance, followed by cluster I and clusters III. Maximum inter-cluster distance was observed between cluster III and VI, followed by that between cluster III and IV and between cluster I and III, suggesting that genotypes belonging to cluster III and VI, III and IV and I and III are more divergent than the rest of the clusters. Per cent character contribution towards genetic divergence was maximum for fruit yield (q/ha), followed by average fruit weight, days to 50% germination, number of seeds/fruit and fruit yield/plant showing selection of these characters. Apart from the above findings it can be concluded that, selection and hybridization of genotypes from high divergent clusters III (Kashi Kranti, Hisar Naveen, P-8) and VI (Punjab Suhavani) and cluster I (NDO-10, Azad Bhindi-1, Kashi Vibhuti, Arka Abhay, Kashi Vardan, Arka Anamika, Kashi Pragati) and cluster III (Kashi Kranti, Hisar Naveen, P-8) are expected to yield potential F1s and transgressive for further exploitation.

A Pathway to Assess Genetic Variation of Wheat Germplasm by Multidimensional Traits with Digital Images.

In this paper, a new pathway was proposed to assess the germplasm genetic variation by multidimensional traits of wheat seeds generated from digital images. A machine vision platform was first established to reconstruct wheat germplasm 3D model from omnidirectional image sequences of wheat seeds. Then, multidimensional traits were conducted from the wheat germplasm 3D model, including seed length, width, thickness, surface area, volume, maximum projection area, roundness, and 2 new defined traits called cardioid-derived area and the index of adjustment (J index). To assess genetic variation of wheat germplasm, phenotypic coefficients of variation (PCVs), analysis of variance (ANOVA), clustering, and the defined genetic variation factor (GVF) were calculated using the extracted morphological traits of 15 wheat accessions comprising 13 offspring and 2 parents. The measurement accuracy of 3D reconstruction model is demonstrated by the correlation coefficient (R) and root mean square errors (RMSEs). Results of PCVs among all the traits show importance of multidimensional traits, as seed volume (22.4%), cardioid-derived area (16.97%), and maximum projection area (14.67%). ANOVA shows a highly significance difference among all accessions. The results of GVF innovatively reflect the connection between genotypic variance and phenotypic traits from parents to offspring. Our results confirmed that extracting multidimensional traits from digital images is a promising high-throughput and cost-efficient pathway that can be included as a valuable approach in genetic variation assessment, and it can provide useful information for genetic improvement, preservation, and evaluation of wheat germplasm.

Variability in antioxidant capacity and some mineral nutrients among ninety-one Indian accessions of bottle gourd [Lagenaria siceraria (Molina) Standl.

Bottle gourd is amongst the widely grown yet under-researched cucurbit vegetable in India and sub-Saharan Africa. The fresh immature leaves, fruit and seed are used for food and medicinal purposes, as rootstock for watermelon. Despite the economic and culinary importance, availability of wide variation in Africa and India, the bottle gourd genetic resources remains under-utilized, particularly with respect to harnessing the nutritional quality. In the present study, we evaluated 91 bottle gourd accessions from India and identified promising bottle gourd accessions for quality traits such as total phenol content, total antioxidant capacity, magnesium, iron, zinc and copper contents. High genotypic coefficient of variation and phenotypic coefficient of variation (>20%) were recorded for all the biochemical traits and mineral nutrients. High heritability (h2) with high genetic advance was recorded for phenol content (99.00/62.76%) and antioxidant activity (99.71/62.58%) whereas high heritability (h2) with low genetic advance was recorded for all the mineral nutrients except magnesium (98.79/49.84%). Simple correlation coefficients among the different traits revealed a highly significant positive association of total phenol content with antioxidant activity, magnesium, iron and zinc content. Euclidian cluster analysis grouped 91 accessions into 12 clusters based on Ward's distance. Eigen value from principal component analysis depicted the first two components accounted for 62.43 cumulative percent of total variation which signifies a high degree of correlation between the analyzed traits. The promising accessions IC-0336825, IC-0385814, IC-0418246 and IC-0284925 and check cultivar Pusa Santusthi for phenol content, antioxidant activity and mineral nutrients (Mg, Fe, Zn and Cu) may be used as donors in the quality breeding program in bottle gourd. The implication of identified promising bottle gourd accessions for development of new cultivars in bottle gourd is discussed.

Genetic Variability Studies in Advanced Breeding Lines of Brinjal (Solanum melongena L.) for Fruit Yield and Quality Parameters

An experiment was carried out to assess genetic variability in thirty advanced breeding lines of brinjal during Rabi season 2021-2022 at the College of Horticulture, Mudigere. The experiment was laid out in randomized complete block design with three replications. Analysis of variance indicated the presence of large variability for different characters under study. The genotypic coefficient of variation and phenotypic coefficient of variation was high (>20 %) for the number of primary branches at 30 DAT, average fruit weight, whereas, plant height at 30 and 90 DAT, number of primary branches at 90 DAT, stalk length, fruit yield per plot, estimated fruit yield per hectare, dry matter content and fruit phenol content showed moderate GCV and PCV. High heritability coupled with high genetic advance (>20 %) in per cent of mean were recorded for plant height at 30 DAT, number of primary branches at 30 and 90 DAT, days to first flowering, average fruit weight, stalk length, fruit yield per plot, estimated fruit yield, dry matter content and fruit phenol content indicating that these traits are controlled by additive gene action. Therefore, studied characters may be included in assortment criterion for improvement in fruit yield per plant and yield contributing traits.

Utilizing genetic variability parameters of garden pea (Pisum sativum L.) germplasm for yield and quality traits

In present study, 159 diverse pea genotypes were evaluated at Vegetable Research Farm, Punjab Agricultural University, Ludhiana, Punjab, India to study genetic variability, heritability and genetic advance involving 14 morphological traits. The analysis of variance showed significant differences among genotypes for all the traits under study except node at which 1st pod appears. On the basis of mean performance, the maximum yield was observed in PB-90 which was followed by PB-89 and 2009/PMVAR-6. Highest coefficient of variation was observed for number of seeds/pod and highest genotypic and phenotypic coefficients of variation were recorded for number of pods/plant followed by plant height and total yield/plant. Very high heritability estimates were observed for plant height (99.89) followed by total yield/plant (99.71) and days to 1st picking (99.43) while genetic advance as percent of mean was observed high for number of pods/plant (65.35) followed by plant height (58.66) and total yield/plant (42.17). High heritability along with high genetic advance was found for all traits under study. High heritability estimates coupled with high genetic advance reflects the presence of additive gene action for expression of these traits.

Evaluation of genetic variability in fragrant rose (Rosa × hybrida L.) cultivars under open field cultivations

Twenty six rose (Rosa × hybrida L.) cultivars grown for open field conditions were characterized using 16 vegetative and floral traits to obtain information on the nature and magnitude of existing genetic variability. The cultivars, Night Time, Christian Dior and Pusa Abhishek were early in flowering and Local Collection 3, Local Collection 4, Kashmir Velvet and Edouard had longer flowering duration; Christian Dior and Bonne Nuit had bigger flowers; Pusa Bahadur had long flower stalk; Local Collection 3, Local Collection 4, Edouard and Kashmir Velvet were having more number of flowers per plant and Pusa Bahadur, Night Time and Christian Dior were found with higher flower weight and shall help in further selection and hybridisation. The higher genotypic and phenotypic coefficients of variation were recorded for plant height, plant spread (E-W), plant spread (N-S), stem girth, number of shoots/ plant, number of petals/ flower, flower stalk length, number of flowers/ plant and 100-flower weight, indicating that genotypic variation contributed markedly towards total variability for the above traits. There is a greater scope for selection in improving flower yield. The high heritability with high expected genetic advance over mean (GAM) was observed for plant height, plant spread (E-W), plant spread (N-S), stem girth, number of shoots/ plant, flower bud length, flower diameter and flower stalk length. This also revealed the lesser influence of environment on these traits. Therefore, simple selection based on phenotypic values for these traits could be useful in their improvement for achieving higher flower yield. The trait specification identified genotypes could ideally be used as donor parents in rose breeding programme to develop desired genotypes for open field cultivation.

Studies on Genetic Variability, Heritability and Genetic Advance in Garden Pea (Pisum sativum L.) Genotypes under the Central Dry Zone of Karnataka, India

A field experiment was carried out to determine the genetic variability, heritability and Genetic advance present in twenty-two genotypes of garden pea during Rabi season 2021-22 at ICAR-Krishi Vigyan Kendra, Babbur farm, Hiriyur. The experiment was laid out in Randomized Complete Block Design with two replications. Observations were recorded on various yield and yield contributing characters. In general, the magnitude of the phenotypic coefficient of variation (PCV) was greater than that of the genotypic coefficient of variation (GCV) and the narrow difference between them indicates less environmental influence on the expression of the trait. High PCVand GCV (>20%) were recorded on plant height, number of branches per plant, pod thickness, number of pods per plant and non-reducing sugars which indicates the presence of high genetic variation and scope for effective improvement. All the characters studied in this experiment showed high heritability (>60%) in a broad sense coupled with high genetic advance as per cent over a mean (>20%) except for days to first flowering, days to 50 per cent flowering and days taken for first picking. This indicates the existence of additive gene action and the need for population improvement through selection. The genotypes that exhibit specific traits can be used in a hybridization programme

Genetic variability and trait association in Jhum Rice of Arunachal Pradesh, India

The study comprised of 19 jhum rice landraces from different parts of Arunachal Pradesh. The analysis of variance based on 14 quantitative traits revealed significant traits-wise variations across the genotypes. Based on cluster analysis the landraces were grouped into 3 distinct clusters. Principal component analysis (PCA) extracted 5 principal components (Eigen value >1) with 80.5 % of the total variance. About 60.4% of the cumulative variance was exhibited by the first three principal components. Traits like grain yield (GY), plant height (PH), primary branch per panicle (PBP), filled grain per panicle (FGP), test grain weight (TGW) and grain morphology exhibit heavy positive loadings in these first PCs. The value of the phenotypic coefficient of variation (PCV) was higher than the corresponding genotypic coefficient of variation (GCV) for most of the traits. The traits exhibits moderate to high PCV, GCV, heritability and genetic advance as a percent of the mean (GAM). High heritability couple with high GAM was exhibited by GY, TGW and PH. While moderate heritability with (GAM) was exhibited by panicle length (PnL), FGP and PBP. Except ligule length (LgL) and flag leaf width (FLW), all the traits displayed positive associations with GY. A high positive significant correlation (P≤ 0.01) was exhibited by grain width (0.716) and TGW (0.583). Path coefficient analysis revealed direct positive effects on GY by girth diameter (GD), flag leaf length (FLL), blade leaf width (BLW), filled grain number per panicle (FGP), TGW, and grain length (GL). The residual effect magnitude of 0.1386 indicated that 99.8 % of the variability was accounted by the traits included in the present study. Thus the study revealed information about the genetic diversity among the jhum rice landraces and associated yield contributing traits for future breeding programme.

Genetic Variability Studies in Chilli (Capsicum annuum L.) Genotypes under the Mid Hill region of Himachal Pradesh, India

A field experiment was carried out at the Vegetable farm of Dr Y S Parmar University of Horticulture and Forestry, Nauni to evaluate variability parameters of fifteen yield and yield contributing characters in twenty-five chilli genotypes during the Kharif season 2020-21. The analysis of variance revealed significant differences among all the genotypes studied. High phenotypic coefficient of variation (PCV) and genotypic coefficient of variation (GCV) were observed for nine characters except for days to 50% flowering, fruit length and fruit diameter, plant height, days to maturity (mature green) and days to maturity (red ripe stage). High estimates of PCV and GCV coupled with high heritability and genetic gain were recorded for nine traits indicating the existence of additive gene action and these traits can be improved through selection.

STUDIES ON CHARACTER ASSOCIATION AND PATH COEFFICIENT ANALYSIS FOR YIELD AND YIELD RELATED TRAITS IN GREENGRAM [VIGNA RADIATA (L.) WILCZEK

Genetic association and path coefficient analysis were studied at phenotypic and genotypic levels in 19 genotypes of greengram for various quantitative characters during kharif 2022. The experimental design which was used to conduct the experiment was a randomized block design. Analysis of variance revealed highly significant differences among the genotypes for all the characters under study indicating the presence of adequate variability among the varieties. Estimates of phenotypic coefficient of variation (PCV) were higher than genotypic coefficient of variation (GCV) for all characters. High heritability was observed with high genetic advance as mean percentage by 100 seed weight, biological yield and harvest index. Number of clusters per plant, number of pods per plant, number of seeds per pod, 100 seed weight, harvest index and seed protein content showed significant and positive phenotypic correlations in seed yield per plant. Specific seed yield per plant showed significant and positive genotypic correlation with number of clusters per plant, number of pods per plant, number of seeds per pod, 100 seed weight, harvest index and seed protein content. High magnitude of positive direct effect at phenotypic level on grain yield per plant was shown by number of clusters per plant, number of pods per plant, pod length, number of seeds per pod, 100 seed weight, biological yield, harvest index and seed protein. High intensity of positive direct effect at genotypic level on seed yield per plant, number of clusters per plant, harvest index, biological yield, plant height and number of pods per plant was applied by material.

Elucidation of genetic variability, heritability, correlation and path coefficient in carrot (Daucus carota L.)

An experiment was conducted at the Punjab Agricultural University, Ludhiana, India, for 2 years (2019-20 and 2020-21), to study the genetic variability, heritability, correlation and path coefficient analysis in 28 genotypes of Asiatic carrot under 8 environments. The experiment was laid out in RBD with three replications. The analysis of variance showed that the genotype’s mean sum of squares was significant for all the traits studied, indicating that significant variation existed among them. A wide range of variation existed for average root length, root weight, root diameter, core diameter and root shoot ratio i.e., 14.5-21.0 cm, 40.9-77.8 g, 2.2-2.7 cm, 0.93-1.56 cm and 0.86 to 1.29, respectively. The average marketable yield of genotypes ranged between 365.55 to 584.55 q ha-1. Vegetative traits like shoot length varied from 42.0-64.7 cm, shoot weight from 44.71-80.14 g, and the number of leaves from 5.4 -7.2 among all genotypes. The magnitude of phenotypic coefficient of variation was greater than the corresponding genotypic coefficient of variation for all the traits indicating that trait expression is environmentally influenced. Root-shoot ratio, shoot length, number of leaves, root length, and root diameter all have exhibited highest heritability and moderate genetic advance that suggested additive gene action. Strong character association of root length, root diameter and root weight with marketable yield suggested as selection criteria for higher yield.

Estimation of Genetic Variability Parameters and Parent-offspring Correlation, Regression in Groundnut (Arachis hypogaea L.)

Genetic variability is major component which helps in selecting better genotypes under different environmental conditions, with this aim an experiment was conducted to understand the genetic potential, heritability, genetic advance and traits association of yield contributing characters for F6 and F7 families derived from the cross GKVK-6 × KCG-2 at the University of Agricultural Sciences, Bangalore in an augmented block design along with three checks viz., TMV-2, KCG-6 and KCG-2 during summer and Kharif 2017. Results from analysis of variance (ANOVA) revealed that highly significant differences were observed for all the characters studied. High genetic variability was observed for major yield contributing characters like the number of pods per plant (g), pod yield (g), kernel yield per plant (g), SMK% (sound mature kernel per cent), SCMR (SPAD chlorophyll meter reading) and SLA (specific leaf area) (cm2/g). Narrow difference between GCV (genotypic coefficient of variation) and PCV (phenotypic coefficient of variation) was observed for pods per plant, pod yield, SCMR and SLA and high heritability coupled with moderate genetic advance per cent mean was recorded for pod yield, SCMR and SLA indicating the involvement of additive gene action in controlling these traits. Three superior families were noticed with more pods plant-1, high pod yield plant-1, high kernel yield-1, high shelling (%), high SMK (%), high SCMR value, and low SLA value. Further, these superior families also revealed the presence of high parent offspring regression and intergeneration correlation, implying increased efficiency of selection for most of the traits considered and these were identified to be the important characters that could be used in selection for yield Keywords: GCV, PCV, Heritability, GAM, water use efficiency, Groundnut.

GENETIC VARIABILITY AND PRINCIPAL COMPONENT ANALYSIS OF YIELD CAUSATIVE CHARACTERS IN BRASSICA NAPUS L.

Current study was conducted at Department of Plant Breeding and Genetics, University of Agriculture, Faisalabad, Pakistan during 2019-20. Genetic variability, correlation (r) and broadsense heritability (h2 BS) were studied in ten diverse accessions of Brassica napus for analysis of yield causative characters. All the genotypes were found to be significantly different from each other for all studied traits which shows variability among genotypes. High values of phenotypic co-efficient of variance (PCV) and genotypic coefficient of variance (GCV) were observed for branches on the main stem, 1000-seeds weight (g), and the number of seeds per silique which is the sign of the presence of variability in these characters. The same characters depicted the higher heritability (>50) along with high genetic advance which was the indication of an additive type of gene action. The plant height showed significant positive association with branches on main stem (r = 0.73**), thousand (1000)-seeds weight (r = 0.90**), seed yield per plant (r = 0.66*) and oil content (r = 0.65*). The branches on the main stem showed a similar association with seed yield per plant (r = 0.91**) and 1000-seeds weight (r = 0.67*). The results revealed that branches on the main stem, seeds per silique and 1000-seeds weight were improved through mass selection. Principal component analysis revealed that the first four principle components (PCs) contributed up to 95% of total variation whereas, the first PC shared its maximum in total variation and selection from this PC could be exploited in further breeding programs.

Assessment of Genetic Variability to Contribute Yield and its Components Characters in Pigeonpea [Cajanus cajan (L.) Millsp.] Genotypes in Central Plain Agro-Climatic Region of Uttar Pradesh, India

The present investigation entitled “assessment of genetic variability to contribute yield and its components Characters in Pigeon pea [Cajanus cajan (L.) Millsp.]” genotypes in central plain agro-climatic region of uttar pradesh”was conducted at Oilseed Research Farm, Kalyanpur, C. S. Azad University of Agriculture and Technology, Kanpur- 208002 (U.P.) during kharif season 2021-22. Genetic variability studies were carried out for 34 pigeon pea genotypes during the years 2021-2022. The analysis of variance revealed that there was significant amount of variation for all the characters during these years. Days to maturity, plant height, number of secondary branches, days of 50% flowering, 100 seed weight, number of primary branches, biological yield, seed yield per plant, harvest index, number of pods per plant and number of seeds per pod was shown to have identified as high heritability value. High estimate of (phenotypic coefficient of variance and genotypic coefficient of variance) PCV and GCV were observed for the number of secondary branches, number of primary branches and days to maturity while moderate estimate of PCV and GCV were observed for plant height, 100 seed weight, days to 50% flowering, seed yield per plant, number of pods per plant and harvest index. The character association studies revealed that at genotypic and phenotypic level, seed yield per plant had positive and high significant correlation to harvest index, days to maturity, biological yield, 100 seed weight and number of pods per plant.