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An experiment was conducted under normal (with six irrigation during crop period) and stressed condition during Rabi 2019 in All India Coordinated Research Project (AICRP) on Wheat, MARS, Dharwad, Karnataka with the view of assessing genetic variability, heritability and expected genetic advance in 104 F4 families of the cross HD2864 × DBW14. The progenies exhibited wide range of variation for all the traits indicating the presence of enough genetic variability in the material under study. Under timely sown condition, the traits like leaf waxyness, NDVI at different stages, SPAD at different stages, number of productive tillers per plant, seeds per spike, grain filling duration, spike length, thousand grains weight and seed set percentage showed high variability. The traits like plant height, canopy temperature at different stages and membrane stability index showed low variability. Under late sown condition, the traits like leaf waxyness, plant height, NDVI at different stages, SPAD at different stages, number of productive tillers per plant, seeds per spike, yield per plant, row bulk yield and seed set percentage showed high variability. The traits like days to maturity, spike length and membrane stability index showed low variability. The findings shows that all traits related to crop yield are positively linked, except for canopy temperature at different growth stages. Promising lines identified through Heat susceptibility index (HSI) and Heat tolerance index (HTI) can be utilized in future breeding programs to enhance crop productivity.

The present investigation was carried out with 53 genotypes of cowpea to study association among yield contributing traits. The genotypes were sown in a randomized block design replicated with three replications at the National Pulse Research Centre, TNAU , Vamban, Pudukkottai, during Kharif,2022. Observations on ten traits were recorded and subjected to statistical analysis. The coefficient of phenotypic differences was substantially greater than the genotypic variation for all the characters under study, showing that the prevailing variation is mainly governed by the genotypic factor and substantial environmental factors. High heritability and genetic advance as percentage of mean were observed for the traits seed yield and 100 seed weight. This showed the role of additive gene action in the inheritance of these traits which gives the best chance of their improvement through simple selection. Association analysis revealed that number of cluster/plant and number of pods/plant had a significant and positive correlation on seed yield. Yield component traits viz., plant height, number of branches/plant, number of pods/cluster, number of pods/plant, 100 seed weight and seed yield were high inter-correlated among themselves. Furthermore, it was observed that the number of pods/plant, pod length, and 100 seed weight had the maximum positive direct effects on seed yield. So direct selection for these three traits could help to improve the seed yield potential of cowpea.

Fifty selected rice genotypes including two checks were evaluated during Kharif, 2022-23 for genetic variability, heritability and genetic advance as per cent of mean for 16 yield and its attributing traits along with six nutritional parameters in Ranadevi Post Graduate Research Farm, M. S. Swaminathan school of Agriculture, Centurion University of Technology and Management. Analysis of variance indicated highly significant differences among the 50 genotypes studied indicating that substantial variability is present among the genotypes. Total grains panicle-1, filled grains panicle-1, test weight, grain yield plant-1, straw yield plant-1, biological yield plant-1, protein content and mineral contents of Fe, Zn, Cu and Mn exhibited high genotypic coefficient of variation (GCV) and phenotypic coefficient of variation (PCV) suggesting that there is considerable genetic variability among the genotypes studied for the evaluated traits. All 22 traits showed a high heritability (broad sense) coupled with high genetic advance as percent of mean except panicle length, spikelet fertility, harvest index and carbohydrate content, which recorded moderate genetic advance as percent of mean, indicating that additive gene action operates for these traits and has potential for improvement through direct selection methods.

Fourty-eight ashwagandha [Withania somnifera (L.) Dunal] genotypes were studied for the genetic variability, heritability and trait association during 2018-19 based on 13 yield and quality traits. For all the 13 characters studied, highly significant (P < 0.01) differences were observed. Parameters such as withanolides, dry root yield per plant and crude fibre recorded higher estimates for GCV and PCV. High broad sense heritability and genetic advance were recorded for number of primary and secondary branches, number of berries, root length, number of secondary roots, fresh and dry root yield, starch, crude fibre and withanolides. These proved to be promising traits that would respond to selection of better genotypes owing to their high transmissibility and genetic variability. Character association study indicated that dry root yield had positive and significant association with the number of primary and secondary roots, fresh root yield and withanolides at both genotypic and phenotypic levels. Path analysis revealed that number of secondary roots and withanolides were major traits having high positive, direct effect and significant association with dry root yield. Hence, these traits would be quite effective when selected to improve dry root yield in ashwagandha. [ABSTRACT FROM AUTHOR]

Extensive knowledge on the variability parameters and frequency distribution of desirable traits could assist the plant breeders in formulating selection criteria for enhancing the genetic gain under selection. The F2 populations of two greengram crosses viz., COGG13-39 x VGG16-058 and COGG13-39 x VGG18-002 were evaluated for nine biometrical traits during rabi, 2022. Magnitude of difference between PCV and GCV estimates was less than 2.50% for traits viz., pods/plant, pod length, seeds/pod and hundred seed weight in both the populations. High heritability and GAM coupled with moderate to high GCV observed for pods/cluster, pods/plant, hundred seed weight and seed yield/plant signifies the role of additive gene action. Frequency distribution results pointed out that these traits were positively skewed in both the populations. Therefore, stringent selection of segregants with desirable traits and utilizing them in yield improvement programme in greengram can be effectuated. [ABSTRACT FROM AUTHOR]

A total of 64 medium duration rice accessions were evaluated for their genetic variability and genetic divergence during Rabi season 2020 at Pandit Jawaharlal Nehru College of Agriculture and Research Institute, Karaikal. Analysis of variance revealed significant differences for all the traits considered for the study. The traits spikelets per panicle and filled grains per panicle recorded high GCV as well as PCV thereby indicating that these traits would be improved effectively through selection. Other yield component traits viz., plant height, productive tillers per plant, spikelets per panicle, filled grains per panicle, fertility per cent, grain weight and single plant yield revealed high heritability coupled with high genetic advance, indicating that simple selection could be effective for improving these characters. The D2 values and hierarchical clustering analysis grouped the 64 germplasm into seven clusters. In both the clustering methods, the genotype Gold 44 was grouped under separate clusters indicating that, this is a diverse genotype among all the genotypes taken for study. Further, genotype AD 16124 was grouped under the same cluster in both the clustering methods with the highest cluster mean for grain yield per plant. Hence, this genotype could be efficiently utilized for the yield improvement programme in rice.

Little millet is one of the underutilized crops among the cereals, which is being cultivated by farmers of tribal agriculture. The landraces under cultivation possess excellent variability presenting good opportunities for selection. In view of this, the current study was carried out with 17 little millet landraces for 10 quantitative and nine qualitative traits. The study revealed the preponderance of additive gene action for all the 10 traits and hence effective selection could be done for their improvement. Higher to moderate ranges for PCV and GCV with minimum ECV for genetic variability for all the traits were observed. Among the nine qualitative traits, there were significant variations observed for inflorescence shape and panicle compactness. Hence, these traits could be utilized as major DUS descriptors in differentiating the little millet landraces in future. Further the PCA analysis exhibited three reliable principal components contributing to an overall variation of 74.54%. The traits such as days to 50% flowering, peduncle length and flag leaf length were the major positive contributors for variability across all the eigen vectors. These traits were found to exhibit a higher variability among the population and thus a rewarding selection and hybridization for improving these traits could be effected in future breeding programs. Among all the landraces and varieties chittan samai, perunsamai, ATL 1, CO 4 (samai), paakulam karunjamai and vellai samai could be further identified as desirable donors for improving the yield parameters in little millet breeding programs in future.

Extensive knowledge on the variability parameters and frequency distribution of desirable traits could assist the plant breeders in formulating selection criteria for enhancing the genetic gain under selection. The F2 populations of two greengram crosses viz., COGG13-39 x VGG16-058 and COGG13-39 x VGG18-002 were evaluated for nine biometrical traits during rabi, 2022. Magnitude of difference between PCV and GCV estimates was less than 2.50% for traits viz., pods/plant, pod length, seeds/pod and hundred seed weight in both the populations. High heritability and GAM coupled with moderate to high GCV observed for pods/cluster, pods/plant, hundred seed weight and seed yield/plant signifies the role of additive gene action. Frequency distribution results pointed out that these traits were positively skewed in both the populations. Therefore, stringent selection of segregants with desirable traits and utilizing them in yield improvement programme in greengram can be effectuated.

Maize is one of the important cereals in the world. It is a good source of carbohydrates (70-87%) and protein (6-13%). To develop a high-yielding variety of any crop, heritability and genetic advance are important selection parameters for the selection of yield and yield attributes. In this regard, the present investigation was carried out at the Namdeo Umaji Agri Tech India Private Limited, Pune, during Kharif, 2022 to study the extent of variability among maize genotypes. Observations were recorded on 19 polygenic traits and the mean values were subjected to statistical analyses. High GCV and PCV were recorded for anthesis and silking interval, number of leaves, lodging percentage, number of kernels per row and grain yield per plant. High heritability accompanied by high genetic advance was noted for anthesis and silking interval, lodging percentage, grain yield per plant, number of leaves per plant, number of kernels per row, number of tassel branches, leaf width, days to 50% silking, protein content, leaf length, number of kernel rows per cob, cob diameter and cob length. It indicates that these traits are governed by additive gene action and selection will be rewarding for improving these traits in maize.

Thirty advanced lines of wheat obtained from Borlaug Institute for South Asia (BISA), Ludhiana, Punjab were evaluated in a Randomized Block Design (RBD) with three replications for yield and its contributing characters at Agriculture Research Farm, Department of Genetics and Plant Breeding, School of Agriculture, Lovely Professional University, Phagwara, Punjab, India during rabi 2021-2022. Genetic variability, heritability and genetic advance per cent of the meanand analysis of variance were carried out for 14 traits. The mean sum of square (MSS) due to genotypes was highly significant for all the fourteen traits. Grain yield per plant exhibited the highest phenotypic coefficient of variation (PCV) followed by harvest index, the number of spikes per plant, the number of tillers per plant and biological yield per plant. Genotypic coefficient of variation (GCV) was found to be highest for grain yield per plant followed by harvest index, the number of spikes per plant, the number of tillers per plant and biological yield per plant. Very high heritability estimates were associated with high estimates of genetic advance for the number of tillers per plant, the number of spikes per plant, biological yield per plant, harvest index, grain yield per plant, chlorophyll content, and flag leaf area which revealed the presence of additive gene effects, showing the efficiency of selection method of breeding for improving these attributes in wheat.

Two hundred germplasm lines of upland cotton (Gossypium hirsutum L.) were evaluated for genetic variability and divergence for seed cotton yield attributing traits and fibre quality traits at Regional Agricultural Research Station, ANGRAU, Lam, Guntur. The analysis of variance indicated significant genetic variability among the germplasm lines. The close symmetry between the phenotypic and genotypic coefficient of variances and lower values of environmental coefficient variance for all the studied attributes indicated that the traits were genetically controlled and under less influence of the environment. Higher broad sense heritability and genetic advance for all seed cotton yield attributing traits indicated that these attributes were governed by additive genes and early phenotypic selection for their improvement might be effective. Five principal components (PCs) were depicted as having Eigen value >1 and cumulative variability of 66.17%, out of which PC1 accounted for 26.81% and PC2 for 14.08% of variability. The attributes of significance depicted in PC1 were seed index, lint index, upper half mean length, uniformity index, and staple length. Bi-plot revealed that Lam GPC232, Lam GPC223, Lam GPC225, Lam GPC135, Lam GPC62, Lam GPC85, Lam GPC168, and Lam GPC203 were the most divergent germplasm. These genetically diverse genotypes with the absolute and significant association of attributes could be utilized in a future cotton breeding program.

One hundred upland cotton germplasm accessions were evaluated for eight traits to evaluate the per se performance, genetic variability, heritability, genetic advance as a per cent of mean, correlation and path analysis. The estimation of variability indicated that the number of monopodia per plant had high GCV and PCV. High heritability along with high GAM was found in plant height, internode length, the number of monopodia per plant, the number of sympodia per plant, the number of bolls per plant and seed cotton yield per plant which suggested that additive gene activity had a significant influence in the inheritance of these traits. Correlation analysis showed that the number of sympodia per plant, the number of bolls per plant and boll weight have a significant high positive correlation on the seed cotton yield. Path analysis showed that the number of bolls per plant and boll weight had the highest positive direct effect on seed cotton yield per plant.

The study was aimed to investigate the degree of genetic variability, heritability, and genetic advance among eight parents and fifty-six hybrids. The experiment was laid out in a randomized complete block design with two replications. The genetic parameters for 18 yield components and fibre quality traits were assessed. Analysis of variance was found to be highly significant for all the tested traits. Assessment of mean performance indicated the heterotic potential of hybrids over parents. The phenotypic coefficient of variation was slightly higher than the genotypic coefficient of variation suggesting a high level of environmental influence on these characters. The number of monopodia per plant and the number of bolls per plant had high PCV and GCV. High heritability coupled with high genetic advance was reported for the number of monopodia per plant, the number of sympodia per plant, the number of bolls per plant, boll weight, the number of seeds per boll and seed cotton yield, which implies additive gene effects and selection based on these traits will be effective for future crop improvement.

Genetic variability for plant type and seed yield components among 318 recombinant inbred lines of Pigeonpea [Cajanus cajan (L) Millspaugh] was studied during the Kharif season of 2017-18 and 2018-19. The characters studied include plant height, the number of primary branches, the number of secondary branches, days to flowering, and days to maturity, the number of pods per plant, the number of seeds per pod, pod bearing length and branching angle with the main axis. Significant genetic variability was observed among the recombinant inbred lines. Remarkable genotypic differences were found for many of the traits under study. The recombinant inbred line population studied under two environments showed less genotype and environment interaction. The difference between the phenotypic coefficient of variation (PCV) and genotypic coefficient of variation (GCV) is less indicating high heritability of the traits under study and control of additive gene action. The genetic advance over the percentage of the mean was also high for all the traits under study. From the study, it was inferred that genotypes with determinate plant types with a greater number of pod and primary branches early flowering and early maturing with high seed weight and acute branching angle play a significant role in enhancing the yield.

The genetic study was conducted among 68 genotypes comprising restorers and maintainers on milo and maldandi cytoplasm. Among the lines, IS 12735, DSMR-8, IS 33353 and IS 24175 exhibited full restoration on milo and DSMR- 4 and DSMR-8 on maldandi. The lines viz., IS 30383, IS 29335, IS 29914, IS 8012 and IS 12308 exhibited perfect maintainer reaction on both milo & maldandi. High heritability and genetic advance were observed for most of the traits. G x E interaction was also found to be high for the majority of the traits. A high amount of genetic variability among the population indicated an increased opportunity for the selection of restorers, maintainers as the variation is heritable.

The field experiment comprised of 30 cowpea genotypes were evaluated for genetic variability for important quantitative and quality traits during the Summer 2019 season. Analysis of variance showed that there was significant differences among the genotypes evaluated for all the characters studied. A high value of phenotypic coefficient of variation than genotypic coefficient of variation was observed for all the characters which revealed the influence of environment for phenotypic expression of the traits. High heritability and the high genetic advance were observed for days to 50% flowering, leaf width, the number of nodes on main stem, the number of main branches, the number of pods per plant, length of pod, the number of seeds per pod, test weight, seed yield per plant, fat content, lignin content and host preference mechanism of pulse beetle on the grain of cowpea indicating that the characters are governed by additive gene action and the characters which can be improved by simple selection. On Mahalanobis D2 statistics, the genotypes were grouped into four clusters. A maximum number of genotypes was observed in cluster I with 16 genotypes followed by clusters II and III with 8 genotypes each and cluster IV with solitary genotype. On the basis of divergence classes studied the genotypes viz., PMCP-1021, CP-20, CP-25, CP-26, CP-7, CP-2-1, CP-15, CP-9-1, CP-17, CP-2-1, PCP-1809, PCP-1124, PCP-1123, Phule Rukmini and Phule Pandhari can be used for the further breeding programme.

Barnyard millet is an important short duration nutricereal. A study was conducted to measure the pooled variation and association among yield and its component traits in 27 barnyard millet genotypes raised in six locations. The experiment was raised in RBD with three replications. The pooled ANOVA revealed significant difference between genotypes. High PCV and GCV were recorded for number of productive tillers, flag leaf length, flag leaf breadth, single ear head weight, fodder yield per plant, grain yield per plant. Except for days to maturity, all attributes were governed by additive gene effects, which was evident for high heritability and genetic advance values. Correlation studies exhibited significant positive relationship of grain yield with panicle length, single ear head weight, thousand grain weight and fodder yield per plant. Results of path coefficient analysis indicated that single ear head weight and days to first flowering had direct effect towards grain yield. Thus, by using single ear head weight and days to first flowering as selection indices, grain yield of barnyard millet could be augmented.

Thirty-two cowpea genotypes were evaluated in randomized block design to assess the nature and magnitude of variability, heritability and genetic advance for ten quantitative traits. Analysis of variance unveiled that differences among the genotypes were significant for all the characters considered indicating the presence of a substantial amount of genetic variation among the germplasm studied. High estimates of GCV and PCV were recorded for clusters per plant, seed yield per plant, pods per plant, plant height and seeds per pod, while high estimates of heritability were recorded for all the characters under study. High heritability coupled with high genetic advance as per cent of mean was observed for plant height, seed yield per plant, clusters per plant, pods per plant, test weight, seeds per pod, pod length and branches per plant suggesting predominance of additive gene effects and these characters could be improved through selection.

The present investigation was conducted for character association and their causal effect of quantitatively inherited characters with 21 genotypes of pigeonpea. The genotypic and phenotypic coefficient of variation exhibited high for secondary branches per plant (21.07 and 21.94%, respectively), while low was found for days to maturity (3.71 and 3.82 %, respectively) and days to 50% flowering (4.82 and 5.25 %, respectively). Heritability coupled with genetic advance also observed high for secondary branches per plant (92.26 %). The seed yield showed highly significant and positive correlation with plant height (0.806 and 0.619) at both genotypic as well as phenotypic level, respectively. The path coefficient exhibited the highest positive direct effect of plant height (0.871) followed by primary branches per plant (0.423) and days to 50% flowering (0.171) on seed yield, at genotypic level. The highest positive direct effect on seed yield was exhibited by plant height (0.595) followed by primary branches per plant (0.235) and 100-seed weight (0.190), at phenotypic level. The genotypes viz., BAUPP 1610, AKTM 1637, BDN 716, ICPL 15072, WRG 327 and GJP 1820 were found promising in terms of yield and its attributing traits.

The purpose of this study was to determine the nature, extent and magnitude of genetic variability, as well as estimate of the coefficient of variability, heritability and genetic advance as a percentage of the mean. During the rabi, 2020-21, twenty-three diverse genotypes of carrot were laid out in RCBD design at the Experimental Farm of the Department of Vegetable Science, College of Horticulture and Forestry, Neri, Hamirpur, Himachal Pradesh. Observations were recorded on sixteen economic traits. For all traits, significant differences were found among all genotypes. PCV was greater than the corresponding GCV for all the traits, indicating that the environment has a significant impact on character expression. GCV, heritability and genetic advance as per cent of mean were high for root: shoot ratio, plant height at harvest, carotene content and total yield per plot, indicating that selection for these traits would be beneficial in improving carrot yield.

An experiment to estimate the extent of variability, heritability and genetic advance as percent of mean on twenty accessions of Indigofera tinctoria collected from diverse geographical locations and raised in the Orchard unit of the Department of Horticulture, Faculty of Agriculture, Annamalai University. The experiment was laid out in a randomized block design with three replications. The biometric observations of plant height, plant spread, the number of branches, the number of leaves, leaf area, biomass, fresh weight of shoots, fresh weight of leaves, glucoside content, indigo content dye yield and dye recovery were recorded at 160 days after sowing. High GCV estimates were recorded for dye yield, leaf area, dye recovery, glucoside content, the number of branches, the number of leaves, indigo content, plant height, fresh weight of leaves and fresh weight of shoot. The high heritability estimate for the glucoside content (82.02 %) revealed the possibility of increasing the glucoside content. The character dye yield was positively and significantly correlated with plant height, plant spread, the number of branches, the number of leaves, leaf area, fresh weight of leaves, fresh weight of shoot, biomass, glucoside content, dye recovery and indigo content both at genotypic as well as phenotypic levels.

The study was initiated to generate genetic information on important yield contributing characters of sweet potato genotypes maintained in Chhattisgarh. Twenty eight sweet potatoes (Ipomea batatas L.) genotypes were evaluated to estimate the genetic variability for different characters. The experiment was conducted using a Randomized Complete Block Design with three replications. The genetic parameters for yield contributing characters of different sweet potato genotypes were studied. Analysis of variance showed significant variation among the genotypes for all tested characters. The highest tuber yield was recorded in genotype Indira Naveen (27.84 t/ha) which was followed by TSP- 16-8 (25.42 t/ha), Indira Madhur (25.26 t/ha), Sree Bhadhara (24.81 t/ha) and Sree Rethana (24.48 t/ha). Diameter of tubers, vine length, vine internode length, the number of tubers per plant showed the highest genotypic and phenotypic variation. High heritability was observed for characters viz., dry matter of tubers followed by vine length, vine internode length, starch, TSS of tubers, tubers weight per plant, the number of tubers per plant, vine weight per plant, diameter of tubers, dry matter of foliage, length of tubers, harvest index, tubers yield. Variability in vine length, vine weight, dry matter of foliage, tuber weight per plant and tubers yield present in the genotypes could be used for the improvement of sweet potato.

Fifty germplasm lines of kenaf (Hibiscus cannabinus L.) were evaluated to study the genetic variability, heritability, genetic advance, correlation coefficient and path analysis for yield and yield attributes. The differences were statistically significant among the genotypes for all the characters. The genotype KIM-14 was found promising for fibre yield and yield contributing characters. The stick weight per plant recorded the highest variance at genotypic and phenotypic levels followed by plant height, days to flower initiation, days to 50% flowering, fibre yield and per cent fibre recovery and the lowest variance was for green weight and basal diameter. The higher phenotypic coefficient of variability (PCV) than genotypic coefficient of variability (GCV) for all the traits revealed that the characters were highly influenced by the environment. Days to 50% flowering showed high heritability followed by days to flower initiation, fibre yield, stick weight and plant height indicates a good amount of additive genetic components, can be easily utilized for the further crop improvement programme. Stick weight and plant height maintained higher and green weight maintained lower genetic advance. The moderate to high genetic advance with higher heritability over per cent of the mean was in stick weight and plant height indicates a preponderance of additive gene action. Thus, selections should make considering these characters to develop high fibre yielding varieties of kenaf. The value of genotypic correlation was higher than the phenotypic correlation indicates to eliminate the environmental effects for strengthening genetic association. The yield contributing characters were significantly associated with fibre yield per plant at both genotypic and phenotypic levels. Basal diameter (1.679) at a genotypic level and stick yield, per cent fibre recovery and days to flower initiation maintained positive phenotypic and genotypic direct effect on fibre yield per plant.