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The material of the present study consisted of twenty four genotypes of cherry tomato to study the genetic components for growth, yield and quality at university orchard, Tamil Nadu Agricultural University, Coimbatore, India. The genetic variability demonstrated that phenotypic coefficient of variation was higher contrasted with genotypic coefficient of variation for all the attributes in 24 genotypes. Even though PCV was more than GCV but the difference was very narrow suggesting that, there was less influence of environment. High estimations of heritability and genetic gain increase were displayed for plant height at final harvest, the number of primary branches plant-1 at final harvest, inter nodal length of main stem, stem girth, the number of flowers cluster-1, the number of flowering clusters plant-1, the number of fruits cluster-1, the number of fruit cluster plant-1, days from fruit set to fruit maturity, per cent fruit set, the number of fruits plant-1, fruit length, fruit girth, fruit width, the number of locules fruit-1, fruit weight, the number of seeds fruit-1, weight of seeds fruit-1, weight of 1000 seeds, yield plant-1, fruit firmness, pericarp thickness, shelf life of fruits, total soluble solids, total sugars, ascorbic acid, titrable acidity, lycopene, total carotenoids, total phenol and total antioxidant. Thus, the selection might be effective for improving these traits.

An experiment was carried out to estimate the genetic parameters such as variability, heritability, genetic advance, character association and path analysis for twelve quantitative characters in 50 genotypes of green gram [Vigna radiata (L.) Wilczek]. The GCV for all the characters studied was less than the PCV indicating the interaction of genotype with the environment. High heritability coupled with high genetic advance as per cent of mean was observed for the number of primary branches per plant, seed yield per plant, plant height, the number of pods per plant, 100 seed weight and days to 50 per cent flowering. Character association studies revealed that the number of pods per plant, the number of clusters per plant, the number of seeds per pod, the number of primary branches per plant, plant height, days to maturity, pod length and 100 seed weight showed a positive and significant correlation with seed yield per plant. Path analysis revealed that the number of pods per plant had a high positive and direct effect on seed yield.

The present investigation was carried out in the F3 population of three black gram crosses viz., LBG-787 x LBG-752, TU-94-02 x KU-1006, and TU-94-02 x LBG-752 along with their parents. High PCV and GCV were recorded for plant height, the number of clusters per plant, the number of pods per plant and seed yield per plant in two crosses, LBG-787 x LBG-752 and TU-94-02 x KU-1006 indicating the existence of wide variability for these traits in the progenies of these crosses. High heritability coupled with high genetic advance as per cent of mean were recorded for plant height, the number of clusters per plant, the number of pods per cluster, the number of pods per plant and seed yield per plant in the cross LBG-787 x LBG-752 and for plant height, the number of branches per plant, the number of clusters per plant, the number of pods per cluster, the number of pods per plant and seed yield per plant in the cross TU-94-02 x KU-1006, respectively. This indicates the scope of selection for these traits in a particular population since there is a wide range of variation and additive gene action for the traits.

The present investigation was carried out at National Pulses Research Centre, Vamban during Rabi 2017-18 season to assess the extent of genetic variability among the newly developed 49 greengram genotypes based on the yield and yield contributing traits. Observations were recorded on days to 50% flowering, days to maturity, plant height (cm), the number of branches per plant, the number of clusters per plant, the number of pods per cluster, the number of pods per plant, pod length (cm), the number of seeds per pod, 100 seed weight (g) and seed yield (kg/ha). The analysis of variance revealed the presence of significant variation for all the characters studied except for the number of seeds per pod. In general, the PCV values were higher than the GCV values indicating the influence of environment in controlling these traits. Among the estimates of genetic parameters, heritability along with genetic advance are normally more helpful in predicting the gain under selection. In the present investigation, plant height, the number of branches per plant, the number of clusters per plant, the number of pods per plant, hundred seed weight and seed yield have recorded a high heritability coupled with high genetic advance. High heritability coupled with high genetic advance indicated that the selection may be effective for these traits.

Twenty groundnut genotypes were evaluated for 14 characters to study the genetic variability parameters, correlation coefficient and path analysis. Analysis of variance showed highly significant differences among genotypes for all the studied characters indicating that adequate variability was found among the genotypes studied for these characters. Days to 50% flowering, number of pods/plant, 100 pod weight, 100 sound mature kernel and sound mature kernel had high heritability coupled with high genetic advance as per cent of mean and medium to high genotypic coefficient of variation indicating selection would be rewarding for improving these traits because of greater control of additive gene effects, while the traits like primary branches per plant, pod yield and kernel yield had moderate GCV and heritability along with high genetic advance as per cent of mean revealed heritable component of genetic variance playing greater role in expression of these traits and selection would be effective. For seed size and quality related traits, medium heritability along with low genetic advance as per cent of mean was observed for KL/KW ratio, protein content, oil content and sugar content indicating high influence of environment on expression of these traits. Genotypic correlation coefficients revealed that pod yield had significant and highly positive correlations with plant height, primary branches per plant, pods per plant, 100 pod weight, 100 sound mature kernel, kernel yield and harvest index, while negative and significant for days to 50% flowering. 100 sound mature kernel and pods per plant had high positive direct effect and also highly significant positive correlation with pod yield. Therefore, selection for both component traits may helpful in identifying genotypes with high pod yield in groundnut.

Twenty six genotypes of pigeonpea were evaluated for 13 agro-morphological characters. Statistical analysis was carried out for estimation of various parameters. The ICPL-87 being shortest genotypes possessed the minimum number of branches, minimum pod weight, lowest 100-seed weight, shortest root length, lowest biological yield per plant and minimum yield per plant. Among all the genotypes, NDA-1 was the tallest genotype. The highest harvest index was showed by NDA-2009-1. Considering the performance of all the genotypes for important characters, including yield, the genotypes; NDA-2009-1, PUSA-992, DA-10-2, MAL-6, ICPL-87 and BRG-2 were promising. Root weight showed very high estimate of genetic advance (85.53%). The value of genetic advance was lowest for root length (20.89%). The residual effect (0.064) indicated that the thirteen characters included in this study explain 93.6 per cent of variation in yield in this population. Plant height, pod weight, root weight and harvest index were positively associated with seed yield simultaneously with positive direct effect. Therefore, direct selection against this character would be effective for seed yield improvement in pigeonpea.

The present investigation was conducted to estimate genetic parameters, correlations and path coefficients from different traits of nine genotypes in guava. The genotypes exhibited a wide range of variability for all the characters studied. The high estimates of GCV and PCV were recorded for fruit yield per plant, fruit weight, plant height, petiole size, acidity and number of seeds per fruit while low GCV and PCV were expressed by E-W plant spread, leaf length, fruit breadth and N-S plant spread. Heritability estimates revealed that all the characters under study ranged from 99.97 for leaf breadth to 61.99 for TSS. Genetic advance as percent of mean varied from 15.13 (fruit breadth) to 70.73 (number of seeds per fruit). High heritability coupled with high genetic advance as percent of mean was recorded for fruit yield, plant height, fruit weight, acidity and number of seeds per fruit indicating that these traits are under the control of additive gene action and phenotypic selection for their improvement will be effective. Significant positive association of fruit weight with fruit length (0.6134) and fruit breadth (0.7622)indicated the importance of these characters during selection for high yielding genotypes in future breeding programs.

The present investigation was conducted to explore the genetic variability, character association and path analysis for yield and yield component traits in maize. One hundred maize inbred lines obtained from Department of millets, TNAU were raised along with five checks in Augmented block design II and observations were recorded on twenty morphological traits. Analysis of variance showed significant genotypic variance for all the characters. High PCV, GCV heritability and genetic advance as percentage of mean were recorded for anthesis silking interval, number of tassel branches, number of kernels per row, grain yield per plant, cob weight, ear height and number kernel rows per cob. This indicated the effectiveness of selection towards these traits. Critical analysis of results obtained from character association indicated that grain yield per plant had positive significant association with cob weight, cob girth, number of kernels per row plant height, cob length, ear height, 100 kernel weight, tassel length and chlorophyll index. Thus selection for these traits could bring about an improvement in yield attributes of maize. Path analysis for the attributed traits revealed the direct influence of cob girth followed by number of kernels per row, shelling percentage, days to 50 percent silking and ear height on grain yield. Hence these traits could be used as an effective selection indicator to identify the elite genotypes from a population.

The knowledge of genetic variability in a given crop species for characters under improvement is important in any plant breeding programme. Genetic parameters for yield and its correspondent characters in rice were estimated from a trial conducted at Rice Research Centre, Agricultural Research Institute, PJTSAU, Hyderabad during Kharif, 2017. In the present study, four Cytoplasmic Male Sterility lines, eight male lines and thirty-two hybrids and four checks were evaluated. The analysis of variance showed highly significant differences among the genotypes for all the characters, indicated the presence of enormous amount of genetic variability. High phenotypic coefficient of variation (PCV) and genotypic coefficient of variation (GCV) was observed for number of grains per panicle (26.55, 23.16) and grain yield per plant (21.67, 21.24) indicating that these characters could use as selection for crop improvement. High heritability coupled with high genetic gain as percentage of mean was observed for number of grains per panicle (70.26, 41.61) and 1000 grain weight (61.9, 29.52) which showed presence of additive gene action and thus the chances of fixing by selection will be more to improve such traits through pure line selection in the evaluated genotypes.

The present study was carried to identify the nature and extend of variability present for stay green and other twelve grain yield attributing traits in the F3 populations of five sorghum crosses viz., K8 × IS18551, CO26 × IS18551, CO26 × B35, CO30 × IS18551 and CO30 × B35. The high mean value coupled with moderate variability was observed for stay green trait in cross CO26 × IS18551 and leaf chlorophyll index, flag leaf length, panicle length, panicle weight and single plant yield in cross CO26 × B35. In cross CO 30 × IS18551, high mean value along with high variability was observed for biological yield and moderate variability for stem girth and number of leaves per plant. High heritability with high genetic advance as per cent of mean indicates that the heritability is due to additive gene effects and selection may be effective. This was observed for grain yield and maximum number of yield contributing traits viz., plant height, number of leaves per plant, panicle length, leaf chlorophyll index, stem girth, stay green trait and biological yield in cross CO26 × B35. Hence among the five crosses, CO26 × B35 considered as a best cross for further evaluation.

The present investigation was carried out with F2 plants of three different crosses of rice viz., BPT 2270 x AD09493, AD 08142 x Co (R) 50 and AD09493 x AD 11168. In this experiment, genetic variability, heritability, genetic advance, correlation and path analysis on seven quantitative traits viz., days to fifty per cent flowering, plant height, number of productive tillers, panicle length, thousand grain weight, spikelet fertility per cent and single plant yield were estimated. In all the three crosses, for the traits, days to fifty per cent flowering, plant height, number of productive tillers and thousand grain weight, minimum difference between PCV and GCV was obtained, indicating lesser influence of environment and more genetic control on the expression of these traits. The results of correlation analysis indicated that number of productive tillers had highest significant correlation with single plant yield and hence simultaneous selection for number of productive tillers, along with high spikelet fertility percentage can significantly improve the single plant yield in rice.

A study was conducted to evaluate stable and heritable variations among 55 turmeric (Curcuma longa L) genotypes in relation to morphological, biochemical, yield and quality traits. High Genotypic (GCV) and Phenotypic Coefficient of Variations (PCV) were registered for most of the traits except number of leaves per plant. High heritability coupled with high genetic advance as per cent of mean was observed for the traits plant height, pseudostem girth, number of tillers, petiole length, leaf area, number of mother rhizomes, weight of mother rhizomes, length of mother rhizome, girth of mother rhizomes, number of primary rhizomes, weight of primary rhizomes, length of primary rhizomes, girth of primary rhizomes, number of secondary rhizomes, weight of secondary rhizomes, length of secondary rhizomes, girth of secondary rhizomes, fresh yield per plant, oleoresin content, curcumin content except core diameter and number of leaves per plant which exhibited moderate and low heritability.

Presence of adequate genetic variability and its critical analysis are needed for initiating any crop improvement programme and for adopting appropriate selection techniques. An investigation was carried out to know the extent of genetic variability present in forty six genotypes of rice during kharif 2017. Analysis of variance revealed highly significant differences for all the 12 characters, indicating the presence of genetic variability among the genotypes. The magnitude of PCV was slightly higher than GCV for the traits viz., plant height, number of tillers per plant, number of panicles, panicle weight, grain number, test weight, single plant yield, plot yield and biomass, indicating less influence of environmental factors on the expression of traits and the possibility for genetic improvement through direct selection for these traits. The estimates of PCV and GCV were moderate for the traits viz., days to 50% flowering, panicle length and harvest index, indicating the influence of environment rather than the genotype alone. The heritability and genetic advance estimates were moderate for panicle length and high for all the other traits viz., days to 50% flowering, plant height, number of tillers per plant, number of panicles, panicle length, panicle weight, grain number, test weight, single plant yield, plot yield, biomass and harvest index, indicating the influence of additive gene action, as such selection would likely be effective for improvement of these traits.

Variability studies revealed that considerable amount of variability exist in the F2 population of rice cross CB 08504 × Prasanna through high values of PCV and GCV for characters like number of filled grains per panicle, spikelet fertility percentage and single plant yield. High PCV and moderate GCV was observed for number of productive tillers per plant while moderate PCV and GCV was recorded for days to first flowering and harvest index. High heritability coupled with high genetic advance as percent of mean was observed for the characters namely number of filled grains per panicle, number of productive tillers per plant, spikelet fertility percentage and single plant yield in the F2 population. The traits days to first flowering, number of productive tillers per plant, panicle length, number of filled grains per panicle, spikelet fertility percentage and harvest index were showing significant and positive correlation with single plant yield. The F2 population of CB 08504 × Prasanna performed better for earliness, yield and yield associated traits and could be utilised in future breeding programs to meet the increasing demand of rice.

Genetic variability, heritability and genetic advance of a character assist in setting up the breeding programmes for the improvement of the particular trait. In the current study high estimates of PCV and GCV were recorded for cob weight and single plant yield among the cross derivatives of UMI 1200 × CE 477. The GCV estimates of single plant yield (23.28 in BC1F1, 38.10 in BC2F1 and 33.23 in BC2F2) was observed in the cross derivatives of UMI 1200 × CE 477. Higher PCV and GCV values were obtained for cob weight and single plant in the other cross UMI 1230 × CE 477 also. The GCV values for single plant yield (39.00 in BC1F1, 39.00 in BC2F1 and 37.11 in BC2F2) were found among the cross derivatives of UMI 1230 × CE 477. The PCV and GCV values suggested sufficient variability and thus offers scope for genetic improvement through selection. Both the characters cob weight and single plant yield exhibited higher heritability associated with high genetic advance and hence direct selection of such characters would be effective in improving the yield.

One hundred and eighty genotypes of cowpea (Vigna unguiculata (L.) Walp) were evaluated during kharif 2017 and thirteen biometrical traits were recorded. Analysis of variance revealed that significant difference existed among the genotypes for all the traits studied. The phenotypic coefficient of variation was higher than genotypic coefficient of variation for all the traits studied. The high estimates of GCV was found in traits viz., number of pods per plant, number of clusters per plant, hundred seed weight and single plant yield. High heritability was observed for plant height, days to 50 per cent of flowering, number of racemes per plant, peduncle length, number of pods per plant, number of clusters per plant, days to maturity, pod length, hundred seed weight and single plant yield. High heritability coupled with high genetic advance as per cent of mean was observed for plant height, number of racemes per plant, peduncle length, number of pods per plant, number of clusters per plant, pod length, hundred seed weight and single plant yield. The high degree of variability was observed among the genotypes for different yield contributing traits. This could be utilised in the breeding programme for the improvement of cowpea.

A knowledge of genetic variability parameters, heritability and genetic advance of the traits is essential in a breeding programme to select and advance a right individual from a population. The aim of this study was to estimate the genetic variability among the backcross (BC1F1, BC2F1) and selfed (BC2F2) population derived from two independent crosses of maize inbreds (UMI 1200 × VQL1 and UMI 1230 × VQL1) and select the efficient individual. Fourteen morphological traits were used to estimate the genetic variability components. The populations exhibited high PCV than the corresponding GCV for all the traits. Yield and its attributes like cob length and girth, number of kernel rows/ cob, number of kernels/ row and 100 grain weight revealed high heritability with high genetic advance as percent of mean in BC2F2 generations of both the crosses. Hence these traits indicated the presence of additive gene action and selection would be effective.

One hundred and sixteen forage-type hybrid parents of pearl millet were investigated in summer season for two years, the results revealed that the traits like number of tillers and leaf to stem ratio (L/S) at first cut (50 days after planting); and dry forage yield (DFY) at second cut (30 days after first cut) had high phenotypic coefficient of variation (PCV) values than genotypic coefficient of variation (GCV), hence selection will not be effective for these traits. Many of the desirable and undesirable forage quantity and quality linked traits under investigation had GCV almost equivalent to PCV, thus selection to improve those traits might be effective. High to moderate heritability coupled with high genetic advance per cent of mean (GA) was observed for plant height in both the cuts, indicating, this trait to be controlled by additive gene action and thus can be improved through selection, while, moderate heritability and high GA was observed for DFY at first cut; for green forage yield (GFY) at second cut and for total green forage yield (TGFY) from both the cuts, hence improvement in these traits will be possible through selection at later generations.

A field experiment was undertaken with a view to know the extent of heterosis, inbreeding depression, heritability and genetic advance for yield and yield components in cowpea [Vigna unguiculata (L.) Walp.]. Six generations viz., P1, P2, F1, F2, BC1 and BC2 of eight crosses involving sixteen diversified cultivars of cowpea [Vigna unguiculata (L.) Walp.] were evaluated for yield and its traits. Significant positive heterosis for seed yield per plant and its related traits followed by significant inbreeding depression indicated major role of non-additive gene actions in the inheritance of seed yield per plant and its attributes. For seed yield per plant top three heterotic crosses were cross II (GC-4 x Pusa komal) followed by cross VIII (Cowpea sabra x Waghai krushi) and cross I (GC-3 x Pusa falguni). High heritability coupled with high genetic advance for cross I (GC-3 x Pusa falguni) and high heritability coupled with moderate genetic advance for cross II (GC-4 x Pusa komal), cross III (GC-5 x Anand cowpea), cross IV (W-203-3 x W-3-1) and cross V (W-502-2 x W-3-2) for seed yield per plant indicated heritability was due to additive gene effects. Involvement of both additive and non-additive gene effects suggested that it would be desirable to follow cyclic method of breeding.

The present study was carried out to assess the genetic variability, heritability, genetic advance for yield and yield component characters in four hundred mutant lines of Rice. The crop was raised during kharif 2013 at Agricultural Research Station (ARS), Gangavathi, University of Agricultural Sciences, Raichur, Karnataka. The trials were set up in augmented design. Highly significant differences were observed for all the characters studied. Genetic variability parameters showed that phenotypic coefficient of variation (PCV) was higher than the respective genotypic coefficient of variation (GCV) and heritability is high for most of the characters. The characters studied in the present investigation expressed low to high heritability estimates ranging from 37.00 to 99.00 percent for normal soil and 52.00 to 99.00 percent for saline soil. High genetic advance as percent of mean along with high estimate of heritability and GCV are also observed for most of the characters. In normal soil, genetic advance was highest (190.58) for number of filled grains per panicle followed by number of grains per panicle (180.8) and lowest (4.47) for panicle length among yield characters. In case of saline soil, number of grains per panicle recorded highest (171.74) genetic advance followed by number filled grains per panicle (166.77) and the lowest (4.76) for per cent chaffyness. Biological yield, number of grains per panicle and number of filled grains per panicle are important in selection programmes aiming to improve rice yield and the breeder may consider these characters as the main selection criteria.

The investigation was carried out to assess growth, yield performance and the extent of genetic variation in thirty banana genotypes found in West Coastal Zone of India for fourteen characters. The genotypes showed substantial variation and the PCV was found greater than GCV for all the characters studied. High heritability in broad sense (h 2 b ) coupled with high genetic advance (GAM) was noticed for ‘number of living leaves at harvest’ and ‘fruit peel thickness’ indicating the role of additive gene action. The important yield characters viz ., bunch and fruit weight with high PCV, GCV, heritability and moderate to high GAM were proved as the primary selection criteria. The genomic group AAA was found better than others in both yield and quality characters at a time. The genotypes ‘Pache Bontha Bathesa’ (ABB) and ‘Udhayam’ (ABB) were found high yielding but considering quality characters, ‘Grand Naine’ (AAA) was found as the best in ecological conditions of the West Coastal Zone of India.

Genetic variability is a crucial tool for improvement of seed yield in sunflower. The analysis of variance of 23 hybrids revealed significant differences for all nine characters studied. The genotypic and phenotypic variation was high for seed yield per plant, head diameter and test weight indicating these characters were amenable for improvement by selection. All characters studied were least affected by environment as shown by correspondence between phenotypic co-variance (PCV) and genotypic co-variance (GCV). High heritability coupled with the high genetic advance was recorded for plant height, test weight, seed yield per plant, volume weight and head diameter. High heritability along with moderate genetic advance was observed for days to 50 per cent flowering and oil content indicating additive gene action controlling these traits.

Muluken Demelie 1 and Abiyot Aragaw 2 Ethiopian Institute of Agricultural Research (Werer Center), P.O. Box: 2003, Addis Ababa Ethiopia 1 International Potato Center – Ethiopia (CIP), .PO Box 10059 Addis Ababa, Ethiopia 2 ABSTRACT Sweet potato [ Ipomoea batatas (L.) Lam.] is important food security root crop in tropical and subtropical regions. It can tolerant of a wide range of edaphic and climatic conditions and grown with limited inputs. Genetic analysis reveals the genetic nature of the inheritance of tuber yield and yield components which is required to design efficient sweet potato improvement breeding strategy. Therefore, the objectives to determine genetic variability and to estimate the association of agro-morphological trait in sweet potato genotypes. Filed experiment was conducted at Were Agricultural Research Center using three varieties and eight accessions in Randomize Complete Block Design (RCBD) with three replications. Data were collected from twelve agro-morphological traits. This analysis of variance revealed significant (p

Sixty rice genotypes were evaluated during kharif 2013 for sixteen quantitative and quality traits to examine the nature and magnitude of variability, heritability, genetic advance and correlation. Analysis of variance revealed that the differences among sixty genotypes were significant for all the characters. The characters viz., number of effective tillers per plant, seeds per panicle and brown rice length exhibited high Genotypic Coefficient of Variation (GCV) and Phenotypic Coefficient of Variation (PCV). Small differences between GCV and PCV were recorded for all the characters studied which indicated less influence of environment on these characters. The characters viz., plant height, days to 50 per cent flowering, days to maturity and seeds per panicle exhibited high heritability coupled with high genetic advance indicating that simple selection could be effective for improving these characters. Grain yield per plant had significant and positive correlation with days to 50% flowering, days to maturity, plant height, effective tillers per plant, panicle length, seeds per panicle and kernel breadth after cooking.

The present experiment comprised with twenty two advanced rice cultures collected from various research institutes and was conducted during Rabi 2015-16 under upland rice ecosystem. The analysis of variance revealed that all the treatments are significant for various characters under studied i.e. days to 50% flowering, plant height, number of productive tillers per plant, number of panicles per square metre plot area, panicle length, number of filled grains per panicle, grain yield per plot, straw yield per plot and harvest index. The higher magnitude of PCV was recorded for number of productive tillers per plant, number of filled grains per panicle, grain yield per plot and harvest index and higher magnitude of GCV was recorded for number of filled grains per panicle. Days to 50% flowering, plant height, number of panicles per square metre plot area, panicle length and number of filled grains per panicle showed high broad sense heritability and moderate for grain yield per plot, straw yield per plot and harvest index. High heritability coupled with high genetic advance was recorded for plant height and number of filled grains per panicle indicated the major role of additive gene action in the inheritance of these characters. Thus, these characters may serve as an effective selection parameter during breeding programme in the upland rice ecosystem.