Phenotypic Coefficient Of Variation Research Articles

Induced genetic variability for quantitative and biochemical traits of local landraces of rajmash (Phaseolus vulgaris) of north-western Himalayas

The present study was carried out during rainy (kharif) seasons of 2020 and 2021 at Regional Horticulture Research Station (Sher-e-Kashmir University of Agricultural Sciences and Technology, Jammu, Jammu and Kashmir), Bhaderwah, Doda, Jammu, Jammu and Kashmir to evaluate genetic variability for quantitative and biochemical traits of local landraces of rajmash (Phaseolus vulgaris L.) of north-western Himalayas. Twenty-two induced mutant lines of rajmash generated with gamma rays and ethyl methane sulphonate were screened for quantitative, qualitative and anthracnose reactions under natural and artificial conditions in the field during kharif 2020 (M3) and 2021 (M4). The highly significant differences imply that induced mutant lines for different traits exhibited substantial amount of genetic diversity. Zinc content (55.38) and grain yield/plant (33.24) both had high phenotypic coefficients of variation, while 1000-seed weight (10.14) and protein content had low values (9.83). Zinc content had highest genetic advance, measured as a percentage of the mean, and the highest heritability, followed by grain yield/plant, iron content, number of pods/plant, number of clusters/plant, days to flowering and number of seeds/pod, whereas days to maturity and 1000-seed weight were moderate. The number of pods/plant (0.774), number of seeds/pod (0.556), number of clusters/plant (0.729), length of pod (0.648) and 1000-seed weight (0.620) all exposed a highly significant relationship with grain yield/plant but the days to flowering (-0.636) and days to maturity showed negative correlation (-0.602). It is obvious that the 9 induced mutant lines of Bhaderwah local and Poonch local i.e. R-BL-M3-1, R-BL-M3-9, R-BL-M3-10, R-BL-M3-12, R-BL-M3-13, R-BL-M3-14, R-PL-M3-18, R-PL-M3-20 and R-PL-M3-22 showed the minimum anthracnose disease incidence along with early emergence and superiority in grain yield/plant compared to controls. These mutant lines may be carried forward for the development of mutant genetic stocks and varietal development programmes of rajmash for north-western Himalayan region.

Genetic Variability in Fusarium Wilt Resistant BC2F1 Lines of Yard Long Bean (Vigna unguiculata subsp. sesquipedalis (L.) Verdcourt) Variety Githika for Yield and its Related Traits

Yardlong bean is a highly popular and profitable vegetable traditionally cultivated in the humid tropics of Kerala and is an inexpensive source of vegetable protein. Developing sustainable host plant resistance mechanisms, such as using the backcross method to introduce single-gene resistance into susceptible crop varieties, is crucial for reducing losses due to Fusarium wilt. In the present study Thirty-five resistant backcross progenies (BC2F1) of Yardlong Bean (Vigna unguiculata subsp. sesquipedalis (L.) Verdcourt) variety Githika were evaluated for various genetic parameters for yield and its related traits using Completely Randomized Design at Department of Genetics and Plant Breeding, College of Agriculture, Vellayani, Trivandrum. High phenotypic coefficient of variation (PCV) and genotypic coefficient of variation (GCV) were observed for traits such as the number of pods per plant, pod weight, pod yield per plant, crude protein content. High Heritability(H) and High Genetic advance as percent mean (GAM) were observed for traits such as Number of pods per plant, Pod weight, Pod length, Number of seeds per pod, Pod Yield per plant, Crude fibre and Crude protein content. This significantly suggest that additive gene action is predominant in these traits and low reliance by environmental factors on these traits, making such character a good candidate for direct selection. The study helps in assessing genetic variability to identify traits as well as lines with maximum similarity with recurrent parent which could be used for further crop improvement program.

Genetic Studies on Variability, Heritability and Genetic Gain of Yield and Yield Related Traits in Foxtail Millets (Setaria italic L.)

The present work comprised of 40 foxtail millet advanced breeding lines obtained from small millet scheme, MARS, Dharwad. These lines with checks viz., DHFT-109-3 and HMT-100-1 were evaluated in replicated yield trial at millet scheme, MARS, Dharwad, during rabi 2020-21 for assessing genetic variability, heritability, and genetic gain among 17 traits. Wide range of variation provides an ample scope for selection of superior and desired advanced breeding lines by the plant breeders for further improvement of these characters. The phenotypic coefficient of variation (PCV) was higher than genotypic coefficient of variation (GCV) for all the traits under study. In the present study foxtail millet advanced breeding lines exhibited moderate PCV and GCV for the most important economic traits viz., panicle length (18.01 and 15.85 % 15.85% and18.01%), panicle girth (15.25% and 15.45%), productive tiller per plant (18.44% and 19.40%) and straw yield per hectare (19.92% and 21.39%). The high phenotypic coefficient of variation and genotypic coefficient of variation were observed for characters viz., specific leaf area (21.08% and 22.44%), specific leaf weight (20.52% and 26.72%), grain yield per plant (9.32% and 10.99 %), grain yield per plot (8.85 % and 10.49%) and straw yield per ha (19.92 and 21.39). Most of the traits viz., plant height(79 %), flag leaf length(98%), flag leaf width ( 80%), number of productive tillers per plant (90%), panicle length(98%), panicle girth (97 %), SPAD at 50 per cent flowering (92%), test weight (63%), specific leaf area (88%), specific leaf weight (87%), grain yield per plant(71%) and straw yield per hectare (87%) showed the high estimates of broad sense heritability (h2 b) indicating the reliability of the estimates for variation between advanced breeding lines and effectiveness of selection.

Phenotypic Trait Analysis of Tomato (Solanum lysopersicum) Genotypes in Qatar and Indian Agro-climatic Conditions

Background: The study included four genotypes of tomato (EC620378, EC620380, EC620383, EC620534) which were cultivated to find out their similarities and differences based on phenotypic traits when they were grown under different soil zones of Doha (Qatar) and Meerut (India) to find out that which of the genotypes can be cultivated better in Qatar and India. Methods: The experiment was laid out in Randomized Complete Block Design (RBCD) with two replications. Statistical analysis for variation in quantitative characteristics among genotypes was done by collecting data in 15 qualitative and quantitative traits. Data showed great variation for almost all the traits. The principal component analysis involved plant height and days to marketable maturity as the most discriminating trait that accounted for greater variability in genotypes in both zones, and they should be considered in tomato improvement programs. The correlation analysis showed that fruit yield per plant was positively and significantly correlated with number of fruits per plant and fruit width. Present findings suggest that the identified superior genotypes may be utilized by different farms to further improve their breeding and cultivation strategies. Result: In Indian soil zone, genotype EC620534 performed extremely well in terms of maximum yield per plant. Similarly, in Qatar soil zone, EC620534 and EC620380 performed well. The phenotypic coefficient of variation (PCV) was higher than its corresponding genotypic counterpart (GCV) for all characters studied showing environmental influence. High broad-sense heritability were recorded for days to marketable maturity, fruit shape index and fruit weight in both agro-climatic zones, they were associated with low genetic advance indicating non-additive gene action and environmental influence, hence, heterosis breeding is recommended.

Evaluation of Genetic Variability for Yield and Associated Traits in Breeding Lines Derived from the Cross RNR-15048 × Tunga

Aims: To evaluate the genetic variability of 45 rice breeding lines for 12 quantitative and 2 qualitative traits, aiming to identify and enhance traits that contribute to improved crop yield and nutritional quality in rice. Study Design: The experiment was carried out in Randomised Complete Block Design with two replications. Place and Duration of Study: During kharif 2023 at Agricultural and Horticultural Research Station, Kathalagere, Davangere. Methodology: The research utilized 45 breeding lines resulting from the cross RNR15048 × Tunga, sourced from the Department of Genetics and Plant Breeding, College of Agriculture Shimoga, along with 5 checks. Data was recorded and analyzed statistically using R software. Results: The significant differences among the breeding lines identified through the analysis of variance highlight the potential for selecting superior genotypes within the studied rice breeding lines. High to moderate values of the genotypic coefficient of variation (GCV) and phenotypic coefficient of variation (PCV) suggest that there is substantial genetic diversity for the traits evaluated, indicating a promising opportunity for genetic improvement through selective breeding. Conclusion: The findings of this study highlight the importance of focusing yield improvement programs on specific traits, including plant height, number of tillers per plant, productive tillers per plant, grains per panicle, filled grains per panicle, test weight, protein content, and overall grain yield. Emphasizing these traits is essential for enhancing the productivity and nutritional value of rice, ultimately supporting food security efforts.

Genetic Variability and Correlation Studies in Red Rice (Oryza sativa L.) for Yield Related Traits and Grain Zinc, Iron and Protein Content

Aims: Nutrient deficiencies, particularly zinc (Zn), iron (Fe) and protein, pose severe health risks especially in children and lactating women. Red rice is significantly rich in iron, zinc and protein compared to white rice. The present investigation was undertaken in this context to elucidate information on variability and character association in red rice genotypes to identify effective selection criteria for grain yield and quality improvement of red rice genotypes. Study Design: Randomized complete block design with two replications. Place and Duration of Study: Zonal Agricultural and Horticultural Research Station, Brahmavar, Udupi during Kharif 2023. Methodology: A total of 108 red rice genotypes were used in the study and observations were recorded for ten characters. Protein was estimated by Kjeldhal method, zinc and iron content by Atomic absorption spectrophotometer (AAS) method. The data collected was subjected to statistical procedures using R software. Results: Analysis of variance revealed significant variation among the genotypes for all the characters studied. Grain Zn (11.4-44.7ppm), Fe (13.11-37.12ppm) and protein (5.0-11.43%) showed wide range of variability. High genotypic and phenotypic coefficient of variation was observed for Zn, number of productive tillers per plant, Fe, grain yield per plant, number of grains per panicle and plant height. Correlation studies revealed that grain yield per plant exhibited significant positive association with yield component traits. Protein and Fe content had negative association with grain yield. Conclusion: The traits that have high PCV, GCV, heritability and genetic advance as per cent mean are controlled by additive gene action which is very valuable for selection. The traits that are positively correlated with grain yield can be used for indirect selection which aids crop improvement. Karthika, Bilihallga and Shahara genotypes have high protein, iron and zinc respectively, which can be used in the further breeding program to develop nutritionally rich varieties.

Estimation of Genetic Parameters in Bread Wheat (Triticum aestivum L.) Genotypes Evaluated Under High Temperature Yield Trial in Ethiopia

The study was carried out to estimate genetic parameters of 49 bread wheat genotypes and standard check evaluated at Kulumsa and Melkasa using alpha lattice design with two replications. The analysis of variance result showed highly significant differences among the genotypes for all traits (P< 0.001), implying the presence of considerable genetic variability for these traits. Out of 50 genotypes, four genotypes such as EBW2113062, EBW2113039, EBW2113037 and EBW2113056 were the top yielding genotypes across the locations. Furthermore, 30 of the 50 genotypes gave grain yield above grand mean whereas 14 genotypes had grain yield above the check, Dursa(1295.05kg/ha). In the other word, about 60% of genotypes were with mean grain yield above the overall mean and 30% of them provided mean grain yield above the check, Dursa, variety. High and moderate heritability estimates were found for most of traits showing that the variation observed was mainly under genetic control. The highest PCV and GCV values were observed for grain yield at both locations indicating better opportunity for improvement in this trait via selection. The phenotypic coefficient of variation (PCV) was generally higher than the genotypic coefficient of variation (GCV) for all characters at both locations. The difference between PCV and GCV was large in TKW followed by PHT and Grain yield indicating that these traits are influenced by the environment. However, differences between them were small for most of the traits indicating low effect of environment on the expression of characters at both locations. The genotypic correlations between grain yield with thousand kernel weights and hectoliter weight were highly significant showing their important contribution to grain yield. Therefore, the identified genotypes with better performance could be utilized in advanced bread wheat yield trial targeted for high temperature condition in the country.

Analysis of Genetic Variability, Heritability and Genetic Advance for Yield and Yield-related Traits of Linseed (Linum usitatissimum L.)

Linseed is recognized as an excellent source of essential minerals, nutrients, and is particularly rich in omega-3 fatty acids and alpha-linolenic acid (ALA), making it highly recommended for cardiovascular health. It is cultivated mainly for both linen and oil production, which is used for the production of paints, varnishes, and linoleum paste. The objective of the present investigation was to analyze genetic variability, heritability, and genetic advance for yield and yield traits among 75 linseed genotypes including ten checks using Randomized Block Design with three replications at Oilseeds Research Farm, Kalyanpur, Chandra Shekhar Azad University of Agriculture and Technology, Kanpur, Uttar Pradesh, (India) during Rabi season 2019-20. Analysis of variance revealed significant variation across all studied traits. The genotypic coefficient of variation (GCV) and phenotypic coefficient of variation (PCV) ranged from low to high, with the lowest GCV and PCV observed for days to maturity, number of seeds per capsule, and days to 50% flowering. Conversely, the highest GCV and PCV values were recorded for seed yield per plant (g), number of capsules per plant, number of secondary branches per plant, and plant height. All traits recorded the highest heritability. High heritability and genetic advance were recorded for seed yield per plant, number of capsules per plant, number of secondary branches per plant, plant height, thousand seed weight, number of primary branches and oil content, indicating the presence of additive gene action for these characters. In conclusion, the genotypes studied show significant genetic variation for yield and its attributes, which should be leveraged in future breeding programs.

Genetic Variability Studies in F2 Populations of Ridge Gourd [Luffa acutangula L. (Roxb.)] for Growth, Yield and Quality Traits

An experiment was conducted to study, genetic variability in ridge gourd during rabi 2024 at College of Horticulture, Bagalkot. The observations were recorded on various growth, yield and quality contributing characters of population-I (ArkaPrasan x Sirsi Local-2) and population-II (Jaipur Long x KLR-5). The analysis of variance indicated the prevalence of sufficient genetic variation among the genotypes from all the characters studied. The high phenotypic coefficient of variation (PCV) and genotypic coefficient of variation (GCV) were observed for node at first male flower appears, node at first female appears, TSS and crude fibre in population-I. Whereas, the traits like vine length, number of primary branches per vine, average fruit weight, fruit yield per vine and crude fibre in population-II. High heritability coupled with high genetic advance were observed for node at first male flower appears, node at first female flower appears, fruit length, fruit diameter, average fruit weight, fruit yield per vine, number of fruits per vine, number of seeds per fruit, fruit tenderness, TSS, crude fibre and vitamin C in the both F2 populations indicating these characters are governed by additive gene action. Hence, direct selection may be followed for the improvement of ridge gourd for these characters.

Genetic Variability and Association Studies for Morpho-floral Traits in Backcross Introgression Lines of Rice (Oryza sativa L.)

Background: Wild introgressions are pivotal in enriching the genetic diversity of cultivated varieties by introducing novel alleles beneficial for crop improvement. Understanding insights into genetic variability and association studies of morphological and floral traits are crucial for enhancing hybrid seed production in rice. Methods: 290 backcross introgression lines (BC4F2) from inter-specific cross of CRMS 32B (maintainer of male sterile line as low stigma exsertion recipient parent) cv. Oryza sativa with Oryza longistaminata (wild rice as high stigma exsertion donor parent) were assessed for 12 morpho-floral traits. The experiment was laid out in randomized complete block design (RCBD) at Institute of Agricultural Sciences, Banaras Hindu University, Varanasi, during Kharif, 2019. Result: ANOVA results showed significant differences among lines for all examined traits. The phenotypic coefficient of variation (PCV) was slightly greater than genotypic coefficient of variation (GCV) for each trait. High PCV, GCV, heritability and genetic advance as percentage of mean were observed for dual stigma exsertion percentage (DSE%) and total stigma exsertion percentage (TSE%), whereas moderate to high values of these parameters were noted for single stigma exsertion percentage (SSE%), grain yield per plant (GYPP), effective tillers per plant (ETPP) and grains per panicle (GPP) traits. Most traits showed positive skewness, except traits SFP (spikelet fertility percentage), SSE% and TSE%. Most traits recorded leptokurtic kurtosis, whereas plant height (PH), GYPP and TSE% exhibited platykurtic kurtosis. TSE% displayed a highly significant positive association with SSE% and DSE%, while GYPP showed a significant positive correlation with ETPP and GPP, presenting a promising opportunity for simultaneous selection of these traits.

Genetic variability, heritability, and genetic advance estimates in selected groundnut genotypes (<i>Arachis hypogaea</i> L.) for agro-morphological and yield traits.

Groundnuts (Arachis hypogaea L.), is a crucial food and oil crop in the tropics, require genetic variability assessment for efficient breeding programs using appropriate parameters like genetic coefficient of variation, heritability estimates, association among yield related traits and genetic advance. This study aims to identify genotypes with desirable traits to improve yield and adaptability, contributing to better crop improvement strategies. The study used a randomized complete block design with three replications, consisting of fourteen selected genotypes. Quantitative traits were used to estimate genetic variability parameters, heritability, and genetic advance. The analysis of variance revealed significant differences (p < 0.005) for all studied traits, indicating greater variability in genotypes. Characters exhibited different levels of variability, heritability, and genetic advance among the genotypes. The estimate of the broad-sense heritability ranged from 13.33% to 33.33% for canopy spread and days to maturity respectively. Low to high phenotypic coefficient of variation (PCV) and genotypic coefficient of variation (GCV) were recorded. The study found that traits such as number of branches, pods per plant, fresh and dry plant weight, kernel yield, pod yield, and shelling percentage showed high genotypic coefficient of variation, moderate broad sense heritability, and high genetic advance. These traits can be beneficial for groundnut improvement through effective phenotypic selection, resulting in high expected genetic gain. The study found that pod yield is significantly correlated with kernel yield, grain length, grain width, 100-seed weight, fresh and dry 100-pod weight, and number of pods per plant. Kernel yield is positively correlated with the number of branches per plant, pod per plant, fresh and dry 100-pod weight, 100-seed weight, grain length, and grain width. In addition, the first four principal components accounted for 90.37% of total variation in all morphological traits.

Genetic Studies on Yield and Its Components in Pigeonpea (Cajanus cajan L. Millsp.)

A field trial was carried out at the International Crop Research Institute for the Semi-Arid Tropics, Patancheru, Hyderabad during Kharif, 2023-24, with the aim of studying genetic parameters for yield and its components among pigeonpea genotypes which provides in developing an apt selection index to be included in the breeding programs. This research was conducted on 200 genotypes of Indian pigeon pea on seven traits. Data were analysed to calculate analysis of variance (ANOVA), phenotypic coefficient of variation (PCV), genetic coefficient of variation (GCV), broad sense heritability (h2bs) and estimated genetic progression as percentage mean using R software v 4.3.1. The results of the analysis of variance showed that there was a significant difference for days to 50% flowering, plant height (cm), hundred seed weight and seed yield per plant among the genotypes. The genotypic coefficient of variance was lower than the genotypic coefficient of variance for all the traits under selection. Higher extent of genotypic coefficient of variation is manifested by days to 50% flowering, plant height, seeds per pod, hundred seed weight and seed yield per plant. High heritability coupled with genetic advance as per cent mean was observed in seed yield per plant, number of days to 50% flowering and plant height. The results concluded that seed yield per plant, number of days to flowering up to 50%, and plant height are the traits that should be emphasized as selection indicator in Indian pigeon pea breeding programs.

Estimation of Genetic Variability for Yield and Its Component Traits in Chickpea (Cicer arietinum L.)

The present investigation was conducted with 12 chickpea genotypes, raised in randomized block design with three replications during the Rabi season 2023-2024 at at Organic Research Farm, Karguanji, Institute of Agricultural Sciences, Bundelkhand University, Jhansi (U.P.). The experiment was laid-out in randomized block design with three replications of the plant geometry was maintained at 30 cm x 10 cm. The present experimental material showed a wide range of phenotypic variation for number of seed per pod, number of primary branches per plant, biological yield per plant and seed yield per plant, number of secondary branches per plant, number of pods per plant and harvest index whereas, low phenotypic coefficient of variation was observed for plant height, 100-seed weight, days to 50 per cent flowering and days to maturity as revealed by high values of Coefficient of Range. The estimates of high heritability coupled with high genetic advance expressed as a per cent of mean were observed for biological yield per plant, seed yield per plant and number of pods per plant manifesting the preponderance of additive gene action on the expression of these traits. In the investigation, genotypes viz., RSG-44 and Aruna were superior not only for seed yield per plant but also related traits like 100-seed weight, biological yield per plant, number of pods per plant and number of primary branches per plant.

Unveiling the genetic variability, character association and principal component analysis for yield and yield contributing traits in brinjal (Solanum melongena) genotypes

The experiment was conducted during rainy (kharif) and winter (rabi) seasons of 2023 and 2024 at Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu to assess 45 brinjal (Solanum melongena L.) genotypes for growth and yield related parameters. The experiment was laid out in randomized block design (RBD) with three replications. The result showed high genotypic coefficient of variance (GCV) and phenotypic coefficient of variance (PCV) values for plant height, number of primary branches/plant, length of fruit and weight of fruit and yield/plant. Whereas, the traits such as days to first flowering, days to 50% flowering, fruit girth, fruit borer infestation and number of fruits/ plant exhibited medium GCV and PCV values. The registered high heritability values ranged from 94.29–99.49% and genetic advance as a percentage of the mean ranged from 19.25–70.25%. Correlation analysis on number of fruits/ plant showed positive and significant association with fruit yield/plant. Principal component analysis showed four principal components with eigen values of unity and accounted for 75.81% of total variance.

Variability assessment and screening of superior rice (Oryza sativa L.) genotypes for grain micronutrients and yield components

The present study was carried out to assess the genetic parameters and divergence in 38 rice genotypes for important yield and grain quality traits. Phenotypic coefficient of variation (PCV) exceeded genotypic coefficient of variation (GCV) for all the traits taken for the study, while high heritability was recorded for all the traits, except kernel length to breadth ratio and grain iron content. The trait number of grains per panicle exhibited high heritability (91.00%) and high genetic advance as a percentage of mean suggesting simple selection may be followed to improve the traits. Cluster analysis grouped the genotypes into seven clusters. The highest inter-cluster distance was observed between clusters VII and IV (537.17). Five genotypes excelled in grain yield, ten genotypes for grain zinc content and one genotype for grain iron content over the check variety Rajendra Bhagwati. Despite high variability in grain zinc and iron content, no genotype surpassed the check variety for all three crucial attributes i.e. grain yield, grain zinc and iron content. The experimental material's variability for grain nutrient status suggests their potential use in biofortification programs. Keywords: Rice, biofortification, micronutrients, variability, genetic diversity, heritability

Nitrogen use efficiency of open-pollinated maize cultivars and topcrosses under low nitrogen soil

The study was conducted to evaluate the nitrogen utilization efficiency (NUE) of open-pollinated maize cultivars under low nitrogen soil conditions. It took place at the Lower Niger River Basin Development Authority in Ilorin, Nigeria, during the 2019 and 2020 cropping seasons. The nitrogen treatments (0, 45, and 90 kg N ha⁻1) were assigned as the main plots, while the genotypes were designated as sub-plots in a split-plot design. The NUE of open-pollinated varieties (OPVs) and Topcrosses significantly increased with the application of 45 kg of nitrogen per hectare compared to 0 kg. Similarly, the maize grain yield for both OPVs and Topcrosses ranged from 1.40 to 3.57 t ha⁻1 and from 1.07 to 2.64 t ha⁻1 across the two years with the application of 45 kg of nitrogen per hectare compared to 0 kg. With the exception of days to 50 % silking, all other traits tested exhibited a significant correlation with grain yield. A gene pool for tolerance to low nitrogen may have been present in the cultivars Dmr-Esr Y Cif 2 and Acr 95 Tze Comp 4C3, which combined well with other cultivars to produce high grain yield and NUE. Topcrosses, including Ev Dt-Y 2000 Str C0 × Tze-W Dt Str C4, Dmr-Esr Y Cif 2 × Acr 95 Tze Comp 4C3, Ak 95 Dmr-Esrw × Tzb Rel D4 CO-W, Dmr-Esr Y Cif 2 × Tze-W Dt Str C4, and Br 9922 Dmr Sr × Ev Dt-Y 2000 Str C0, also demonstrated strong potential for maize grain yield and NUE. This suggests that these crosses could serve as promising candidates for developing low nitrogen tolerance in maize for low nitrogen soil environments. A positive relationship between fertilizer levels, NUE, and grain yield indicates that proper nitrogen fertilizer management can enhance both NUE and the grain yield of maize genotypes. Genetic analysis revealed that both phenotypic coefficient of variation (PCV) and environmental variance (δ2p) were higher than genotypic coefficient of variation (GCV) and genetic variance (δ2g), suggesting that environmental influences were more significant than genetic factors for the tested traits. Consequently, improving these traits may be achieved by manipulating environmental conditions.

Genetic Variability, Heritability, Genetic Advance, Path Coefficient Analysis, and Inter-Character Relationships in Colocynth (Citrullus colocynthis [L.] Schrad.) from Southeastern Villages of the Benin Republic

Genetic improvement of crops for important traits requires reliable estimates of genetic variability. heritability and genetic advance of intending parent materials to identify traits useful in planning an efficient breeding program through selection. Hence, the effectiveness of genetic improvement of a crop depends on the variability in the morpho-agronomic traits of individual genotypes. Understanding the variation that exists will allow the breeder to determine strategies to be adopted in his breeding program. The objectives of the present study were to estimate the magnitude of genetic variability and advance, heritability and inter-character relationships by simple correlations and path coefficient analysis in 40 local colocynth genotypes from Southeastern Benin. The experiment was carried out in a randomized complete block design with three replications in three locations for three years. 34 morpho-agronomic traits were observed in each genotype. Analysis of variance revealed that effects of genotype, genotype by year or location and genotype by year by location interactions were significant (p ≤ 0.01 or 0.05) for all the characters. Phenotypic coefficients of variation (PCV) values were relatively greater than genotypic coefficients of variation (GCV) for all traits. High magnitude of phenotypic and genotypic coefficients of variation as well as high heritability along with high genetic advance were recorded particularly for qualitative traits. All yield components, except time to emergence, time to tailspins, leaf limb width, fruit number per plant, fruit width, seed length, seed tegument percentage and stem pubescence texture, had significant and positive correlations with yield attributes represented by thousand-seed weight (TSW) and seed number per plant (SNP). Path coefficient analysis indicated that all the characters (except leaf pubescence texture, stem pubescence texture, fruit design produced by secondary skin color and male flower size) had positive direct effects on TSW and partly SNP. Results suggested that most of the 34 quantitative and qualitative traits studied could be effectively used as selection criteria in the breeding program of Citrullus colocynthis varieties with high yield.

Genetic variability, character association and path coefficient analysis in okra

A study was conducted to investigate the genetic architecture of different lines for fruit yield and its associated traits in okra. Fourteen parents, consisting of twelve lines and two testers, were crossed using a Line × Tester mating design in the spring-summer season of 2019-20 at Vegetable Research Farm, CCSHAU, Hisar. The resulting twenty-four hybrids were cultivated in a randomized block design with three replications during the rainy season of 2020-21. Fruit yield/hectare showed a significant range from 87.86 to 150.18 quintals with an average of 117.73 quintals. The phenotypic coefficient of variation ranged from 3.91% (test weight) to 20.23% (Number of branches per plant), slightly surpassing the genotypic coefficient of variation which ranged from 1.98% (test weight) to 12.15% (fruit yield) with high estimate of PCV for the number of branches per plant (20.23%) and a moderate estimate of both PCV and GCV for fruit yield (14.67%, 12.15%), number of fruits per plant (14.34%, 12.06%), respectively. This suggests that the traits studied were more influenced by genetic factors than environmental factors. High heritability coupled with high genetic advance as percentage of mean for traits such as number of fruits/plant (70.74%, 20.89%) and fruit yield/hectare (68.65%, 20.74%) suggested that additive genes play a major role in determining these traits respectively. This indicates that it is possible to select high-yielding genotypes by selecting parents with desirable traits. Fruit yield/hectare displayed positive and significant associations with most of the traits like number of fruits per plant (0.95) and plant height (0.36) at phenotypic levels. The number of fruits per plant, 1000 seeds test weight, fruit diameter, and number of branches per plant had the most significant positive effect on fruit yield. Ultimately, such analysis has the potential to assist breeders in formulating their selection strategies aimed at enhancing fruit yield.

Exploring Genetic Diversity for High CBD Content in Cannabis Accessions in Tropical and Subtropical Regions of India.

Cannabis, also known as marijuana or hemp, has been utilized since ancient times for industrial, religious, recreational, and medical uses.However, regardless of the intended use, there are legal requirements for quantitative testing of cannabinoids across the supply chains. This investigation aimed to evaluate the genetic diversity of 54 Cannabis samples collected from tropical and subtropical regions in India. The research found a high genotypiccoefficient of variation(GCV), phenotypiccoefficient of variation(PCV), heritability, and genetic advance for total cannabidiol (CBD) content. The genotypic and phenotypic correlation among the morpho-chemical characters revealed strong positive correlations among most characters. Clustering and Principal component analysis identified three accessions in cluster II (CIM-CS-65, CIM-CS-189 & CIM-CS-64) with high CBD content that could be used for breeding and as sources of high CBD content in Cannabis. CIM-CS-64, with its high CBD content with 0.01%THC content, holds potential as a valuable parental line for utilization in hybridization programs and recombinant breeding. Furthermore, in accordance with the NDPC Act of 1985, CIM-CS-64 can be commercialized for medicinal purposes, making it a promising source for the development of medicinal CBD products.

Exploring Genetic Variability, Trait Associations and Path Coefficient Analysis in Pea (Pisum sativum L.) to Advance Breeding Strategies

The experiment was conducted at seed breeding farm, Department of Plant Breeding and Genetics, College of Agriculture, JNKVV, Jabalpur, Madhya Pradesh, India during the rabi season (November, 2019–April, 2020) to estimate the parameters of genetic variability, assess the correlation among traits, and estimate direct and indirect effects. The ANOVA revealed that the mean sum of squares due to genotypes was highly significant for all the traits. The phenotypic coefficient of variation was higher than the genotypic coefficient of variation for all the characters. High values of phenotypic coefficient of variation and genotypic coefficient of variation were observed for most of the traits, while moderate values of phenotypic coefficient of variation and genotypic coefficient of variation were recorded for 100 seed weight, pod length, days to 50% flowering and days to first flower opening. High heritability with high genetic advance as a % of mean was recorded for most of the traits. Moderate heritability and high genetic advance were recorded for the number of primary branches plant-1, secondary branches plant-1 and pod length, indicating the control of additive gene action. Meanwhile, high heritability with moderate genetic advance for days to maturity showed non-additive gene action. Correlation coefficients and path analysis for phenological and quantitative traits indicated that the most important traits are number of seeds plant-1, number of effective pods plant-1, biological yield plant-1 and harvest index. Hence, directional selection through these traits may effectively improve seed yield and its attributes.