Heritability Values Research Articles

Exploring Genetic Variability and Diversity in Exotic Germplasm Collection of Cocoa (Theobroma cacao L.)

The current research investigates the genetic variation and diversity in exotic accessions of cocoa to identify materials with desired characteristics as well as important traits contributing to yield and variability. The experiment was conducted at Cocoa Research Centre, Kerala Agricultural University, from 2021 to 2023. The study comprises 23 exotic genotypes in which observations were recorded on quantitative traits on flowers, pods, and beans. Statistical analysis was carried out based on the observations recorded. The morphological evaluation revealed ample variability among the genotypes for all the quantitative characters studied. The average dry bean weight recorded was 1.08 grams, which is a desirable trait in selecting individuals with high processing efficiency for the chocolate industry. Characters such as single bean dry weight, pod value, pod index, and efficiency index have recorded high values of GCV, heritability and genetic advance as percent of the mean. Principal component (PC) analysis showed that the first three PCs with more than one Eigen-value contributed to 92.18 percent of total variability among the germplasm. Yield components viz. pod value, total bean weight pod-1 and single bean dry weight significantly contribute to maximum variability among the exotic germplasm. Moreover, genotypes were grouped into five clusters based on hierarchical agglomerative clustering technique. Hybridization program involving superior genotypes identified in diverse clusters as parents can produce high-yielding hybrids. The high values recorded for the genetic parameters by yield components suggest the selection of genotypes based on which can result in better-performing progeny.

Evaluation of Agronomic and Genetic Diversity in M2V1 Generation of Marigold (Tagetes erecta L.)

Marigold (Tagetes erecta L.) is an ornamental plant widely used as a potted or cut flower due to its vibrant colors and diverse flower shapes. High genetic diversity is essential for successful breeding programs aimed at developing superior varieties. Genetic information can be obtained by estimating variance components and heritability values, key parameters in plant breeding. A high heritability value suggests that genetic factors influence a plant's characteristics more than environmental factors. This study assessed the genetic diversity and performance of vegetative propagation from 2nd generation mutant plants (M2V1). The research was conducted at the Pasir Sarongge experimental field in Cianjur Regency from July to October 2023, using a randomized complete block design with 17 genotypes and three replicates. The genotypes included 14 from vegetative propagation of M2V1 mutant plants and three comparison varieties: “Maharani”, “BAIP 2”, and “BAIP 3”. Data analysis was performed using PKBT-STAT 3.1 software, followed by the honest significant difference (HSD) test at the 5% level. The results revealed significant differences among genotypes in plant height, stem diameter, canopy width, leaf width, flower weight, flower diameter, number of flowers per plant, total flower weight per plant, and flower stalk length. Floret types observed were either all ligulate or all tubuligulate, with flower colors ranging from orange to yellow to white. Traits such as canopy width, flower weight, flower diameter, and stalk length, which exhibited broad genetic diversity and high heritability, can be used for selection in future marigold breeding programs.

Impact of Heat Stress on Milk Yield, Milk Fat-to-Protein Ratio, and Conception Rate in Thai-Holstein Dairy Cattle: A Phenotypic and Genetic Perspective.

Heat stress severely affects dairy cattle production and reproduction performances in tropical regions. Genetic selection to maintain adequate yield and reproductive performance while enhancing their ability to withstand heat is essential for improving the genetics of dairy cows. Therefore, in this study, we aimed to estimate genetic parameters affecting production and reproduction performances under heat stress conditions in dairy cattle and to investigate the threshold point of heat stress for milk yield (MY), milk fat-to-protein ratio (FPR), and conception rate (CR) in Thai-Holstein dairy cattle. The data included 168,124 records related to MY and milk FPR and 21,278 records of CR in Thai-Holstein dairy cattle, covering the period from 1990 to 2007. A multiple-trait threshold-linear random regression model based on a Bayesian approach via Gibbs sampling was used to estimate variance components, genetic parameters (heritability values, and genetic correlations), and decline rates for each studied trait. The threshold point of heat stress was identified as a temperature and humidity index (THI) of 76. At THI76, a decline was observed in the MY, milk FPR, and CR of Thai dairy cattle. The heritability estimates for MY, milk FPR and CR were 0.347 ± 0.032, 0.293 ± 0.021, and 0.032 ± 0.001, respectively. The genetic correlation between MY and milk FPR and MY and CR were -0.24 and -0.53, respectively, whereas those between milk FPR and heat tolerance as well as between CR and heat tolerance were -0.48 and -0.49, respectively. In addition, the decline rates in MY, milk FPR, and CR were found to be associated with a high percentage of Holstein genetics. In conclusion, the results obtained in this study reveal that the simultaneous consideration of the MY, milk FPR, CR, and heat tolerance traits of Thai-Holstein dairy cattle is possible. In addition, developing a genetic model that incorporates THI is essential for sustainably addressing heat stress problems.

Among-family variations of wood-color parameters, decay resistance, total phenol, and total flavanol content in the heartwood of the third-generation Acacia mangium in Indonesia

Abstract To evaluate the inheritance of natural durability of Acacia mangium Willd., wood-color parameters (Y [lightness], x [red to green], and y [yellow to blue]), mass loss by a white-rot fungus (Trametes versicolor) and brown-rot fungus (Fomitopsis palustris), and three different extracts (methanol extract, total phenol, and total flavanol content) were measured using the inner and outer heartwood of 10-year-old trees from 20 half-sib families in the third-generation A. mangium in Indonesia. The broad-sense heritability (H 2) values were moderate to high for the wood-color parameters and mass loss by white- and brown-rot fungi (H 2 = 0.210–0.851) and low to moderate for three different extracts (H 2 = 0.000–0.576). Significant negative phenotypic correlations were found between the three different extracts and mass loss by T. versicolor and F. palustris. In addition, negative correlations were found between the wood-color parameters and three different extracts. Similar results were found between the total phenol content and y and between the total flavanol content and Y in genetic correlations. Therefore, A. mangium families with lower Y and y in heartwood could produce progenies with higher total phenol and total flavanol content, leading to higher natural decay resistance.

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.

Short communication: Do veterinary diagnoses coming from electronic recording system of veterinary treatments have the potential to be used for breeding in small populations? The case of the dual-purpose Alpine Grey cattle breed

In cattle breeding, emphasis has historically been placed on productive traits, so-called primary traits, while health and fitness traits have been overlooked due to their low heritability and partly negative genetic correlations with productivity. In addition, the recording of phenotypes caused problems due to a lack of high-quality information and / or high costs of recording. This oversight has additionally led to increased incidences of fertility issues and health problems in cattle populations, resulting in economic losses and consumer concerns regarding animal welfare and food safety. This study investigates the potential use of veterinary diagnoses, collected via the Italian electronic recording system of veterinary treatments, for breeding decisions in the local dual-purpose Alpine Grey cattle breed for which the consideration of functional traits in breeding has also become imperative over the last years. The dataset comprised 97 821 records spanning from 2021 to 2023, representing 8 273 individuals and 18 110 lactations of the Alpine Grey breed. Each record documented the administration of treatments for mammary, respiratory, and urogenital pathologies. After data editing and model development, heritability estimates were obtained for each pathology using univariate linear animal models and gibbs sampling algorithms. Results indicate that mammary pathologies affected the highest number of cows (11%), followed by respiratory (4%) and urogenital (5%) pathologies. Heritability estimates ranged from 0.01 to 0.04 across all traits, confirming generally low heritability values. Respiratory pathologies exhibited the highest heritability (0.04; sd 0.04), followed by mammary (0.03; sd 0.01) and urogenital (0.01; sd 0.01) pathologies. This study, although preliminary, provides valuable insights into the health status of local dual-purpose Alpine Grey cattle and highlights the potential of considering veterinary diagnoses for improving animal health and welfare in dairy cattle breeding. However, the low heritability of these traits, which is consistent with literature data, clearly shows the current limitations of using them for breeding. Further, the diagnostic key of the Italian electronic recording system of veterinary treatments should be specified for the use of health data for breeding purposes, as it is formulated in too general manner in its current form. Nevertheless, their significance for animal welfare and economic sustainability underlines the need for their consideration in dairy cattle breeding. Therefore, further research with larger sample sizes and consideration of additional indicators, such as somatic cell counts, is recommended to enhance the accuracy of genetic evaluations and improve breeding strategies for sustainable cattle production.

Maximizing genetic gains across agronomic and consumer preference traits in St. Augustinegrass breeding

AbstractCombining large multi‐environment trial (MET) datasets to decide which genotypes to move forward in the breeding process can be challenging, especially when dealing with negatively correlated traits. The use of a selection index has long been identified as an effective strategy in these situations. However, the method has found limited application in turfgrass breeding. The objective of this study was to use MET data for St. Augustinegrass [Stenotaphrum secundatum (Walt.) Kuntze] breeding lines evaluated across the southern United States to compare genetic gains achieved with the additive additive genetic index (AI) versus the turf performance index (TPI) incorporating agronomic as well as consumer preference traits. The use of either selection index produced more positive genetic gains across traits than direct selection even in the presence of negative correlations. However, the higher genetic gains obtained with AI versus TPI indicate that the use of an index that weighs traits according to their importance is a better approach for selection. Moreover, under a more stringent selection intensity, none of the best lines identified with AI would have been selected with TPI emphasizing the importance of choosing selection criteria that provide a more nuanced ranking of lines. Additionally, higher heritability values and gains from selection were obtained for turfgrass quality under stress (drought and shade) than under normal conditions indicating that selection under stress environments might be more efficient. Most of the evaluated St. Augustinegrass lines outperformed the checks, further supporting the value of cross‐institutional breeding collaborations.

Environmental and additive genetic factors that affect artificial insemination success in Latxa dairy sheep breed

In the Latxa breed, flocks within the breeding program make use of high genetic value rams to inseminate their ewes once per year. Despite the relevance of the insemination results in the genetic progress and on farms’ productivity, external and genetic factors that affect artificial insemination (AI) success have not been up to now explored in this sheep population. For that, 135,351 edited AI records from 63,480 inseminated Latxa Cara Negra from Euskadi ewes, using 853 service rams, collected between 2000 and 2021, were used. The outcome of an AI event was treated as a binary response of either success or failure in becoming pregnant. To identify the environmental factors influencing the AI result, a multiple logistic regression was first calculated on a selection of variables related to the ewes, to the ram, and to other non-sex-specific aspects. With relevant variables detected, a threshold model, including the pedigree information of the inseminated ewes and the service rams, was used to estimate the genetic components of the trait in both sexes. Findings show that the AI success is higher in ewes who had the previous parturition from an AI event, in those with a lambing-AI interval longer than 210d, with 3 years and 2 lambings, with high prolificacy and in those having their first parturition at 1 year of age rather than at 2 or 3 years of age. In counterpart, the higher the milk produced in the nearest record before AI date, the poorer the AI results. Furthermore, relevant variability was linked to the year of insemination, the herd and the technician in charge of the insemination procedure. Regarding genetic parameters, heritability values, on the observable scale, and repeatability were 0.057 ± 0.004 and 0.204±0.007 in females and 0.009 ± 0.037 and 0.032 ± 0.002 in males, respectively. These results evidence that the AI success is under moderately low additive genetic control, with the surrounding environmental variables being the strongest controlling factor. An effort to enhance some farm management practices should be encouraged to efficiently improve reproductive results. Although genetic selection on AI success is viable, the genetic progress may be scarce. An option to improve reproduction by means of selective breeding might be the development of a multi-trait index.

Heritability and Genetic Advance Studies on Fruit Yield and It’s Attributes Traits in Brinjal (Solanum melongena L.)

The present investigation was conducted at the Main Vegetable Research Station, Anand Agricultural University, Anand during the period of 2023-2024. The experimental material comprised twelve generations viz., P1, P2, F1, F2, B1, B2, B11, B12, B21, B22, B1S and B2S of four families involving eight diverse cultivars of brinjal (Solanum melongena L.) used to study the heritability and genetic advance of brinjal for yield and shoot and fruit borer incidence. The experiment was laid out in a compact family block design with three replications. Higher magnitude of heritability along with a higher value of genetic advance as per cent mean was estimated for day to first flowering in family 2, plant height in family 1 and family 4, leaf blade length in family 4, leaf blade width in family 2, fruit length in all families, fruit girth in family 3 and 4, fruit weight in all families expect to family 2, fruits per plant in family 2, fruit yield per plant in all families expect family 4 and shoot and fruit borer incidence in family 2 which suggested preponderance of additive gene effect. The higher value of heritability coupled with the higher value of genetic advance shows higher selection efficiency, permitting plant breeders to efficiently select individuals or groups of individuals. In crops like brinjal, high narrow sense heritability estimates are particularly beneficial for developing enhanced varieties through the fixation of additive gene effects.

Variation in Seedling Quality Attributes of Lentil (Lens <i>culinaris</i> Medik.) After Harvested Under Different Sowing Dates

Planting dates are the most important components for Lentil seedling growth and development. Seeds planted in diverse environmental situations lead to changes in various seedling development and the final output of the yield. The present study, aimed to assess the effect of different planting (sowing) dates harvested seeds on the physiological properties of nineteen (19) lentil genotypes. Lentil was growing during two consecutive planting days on average the normal (main) 17/08/2021 and lately 16/09/2021, then harvested seed extract after five months of storage, planted CRD with two factorial designs and three replications under laboratory condition within a white plastic container filled with autoclaved 3.0kg sand applying 100ml distilled water. The lentil was grown per standard, and the lentil's postharvest physiological quality parameters were evaluated. Results indicated that the lowest speed of germination index was obtained during late planting time or stress situations on the genotype Adda (8.78) and ILL-1760 (8.94). Seedling length is the seedling vigor criterion and is statistically significantly different between planting dates at 1%. The effect of planting day on seedling fresh weight was significantly different (p < 0.01) on genotype Beredu (0.0022) on the main planting day. The seed viability on vigor index (II) as shown in was affected by planting date (p < 0.01) and genotypes (p < 0.01). The heritability value of shoot length, root length, and seedling fresh weight equal zero was the variation due to environmental it had no genetic effect after five months of storage both main and late planting. The seedling vigor index, fresh and dry weight traits maximum on the main planting day on the genotype Beredu indicates 0.0445, 0.00218, and 0.00045 respectively. Seeds from the main planting day had the best seedling traits performance and recorded minimal germination time compared to late planting seeds. Lentil seeds planted lately finally recorded lower seedling fresh and dry weight, vigor, and speed of germination index as compared to those harvested lentil seeds in main planting dates. As a result, when there is adequate rainfall necessary for lentil growth, development, and final output.

Bayesian approach for assessment of co-variances and genetic parameters of production and reproduction traits in Sahiwal cattle.

Precise as well as unbiased estimates of genetic parameters of economically important traits is important for framing breeding programmes meant for genetic progress of dairy animals. Present work was carried out to assess the co-variances along with genetic parameters of production and reproduction traits in Sahiwal cattle with Bayesian approach. Records of Sahiwal cattle kept at ICAR-National Dairy Research Institute, Karnal, Haryana for the period 1988-2016 were used. Heritability estimates ± posterior standard deviation for 305 days' milk yield (305DMY), lactation milk yield (LMY), lactation length (LL), peak yield (PY), days to attain peak yield (DPY), dry period (DP), gestation period (GP), calving to first insemination interval (CFI), days open (DO) and calving interval (CI) as obtained were 0.23 ± 0.03, 0.26 ± 0.03, 0.18 ± 0.03, 0.18 ± 0.03, 0.07 ± 0.02, 0.08 ± 0.02, 0.08 ± 0.02, 0.07 ± 0.02, 0.09 ± 0.02 and 0.02 ± 0.02, respectively and estimates of repeatability for the corresponding traits were 0.23 ± 0.03, 0.26 ± 0.03, 0.21 ± 0.03, 0.21 ± 0.03, 0.12 ± 0.02, 0.14 ± 0.03, 0.16 ± 0.03, 0.16 ± 0.03, 0.17 ± 0.03 and 0.17 ± 0.03. Moderate heritability values for 305DMY and LMY implies that sufficient additive genetic variability is available to obtain selection response. Repeatability estimates for 305DMY, LMY and PY were moderate, pointing towards the possibility of early appraisal of Sahiwal cattle for selection. Antagonistic genetic associations were observed between reproduction and production traits suggesting that reproduction traits need due attention while selecting high producing Sahiwal animals.

Association of Production and Selected Dimensional Conformation Traits in Holstein Friesian Cows.

The objective of this study was to estimate the heritability of dairy production traits and that for dimensional traits and to calculate the correlation between the two heritability values in a Holstein Friesian cow herd bred in Hungary. Data of 15,032 Holstein Friesian cows born in the period 2008-2018 from 666 sires were collected for the study in 6 large dairy herds. Among the conformation traits, stature (ST), chest width (CW), body depth (BD), and rump width (RW), and for production traits, in the first lactation of cows, the 305-day milk yield (MY), milk butterfat yield (FY), and milk protein yield (MY) were evaluated. Heritability estimates of ST, CW, BD, and RW were 0.49, 0.25, 0.31, and 0.30, and those of MY, FY, and PY were 0.40, 0.35, and 0.30, respectively. BD and RW had no phenotypic (b = -0.01) or genetic (b = 0.00-0.01) change. The production traits (MY, FY, PY) increased to a greater extent (b = 2.2-43.3) than the examined conformation traits over time. Consequently, it is indicated that the selection for dairy production did not result in an increase in the studied dimensional traits.

Genotypic variation in blueberry flower morphology and nectar reward content affects pollinator attraction in a diverse breeding population

BackgroundPollination is crucial to obtaining optimal blueberry yield and fruit quality. Despite substantial investments in seasonal beekeeping services, blueberry producers consistently report suboptimal pollinator visitation and fruit set in some cultivars. Flower morphology and floral rewards are among the key factors that have shown to contribute to pollinator attraction, however little is known about their relative importance for improving yield in the context of plant breeding. Clarifying the relationships between flower morphology, nectar reward content, pollinator recruitment, and pollination outcomes, as well as their genetic components, can inform breeding priorities for enhancing blueberry production. In the present study, we measured ten flower and nectar traits and indices of successful pollination, including fruit set, seed count, and fruit weight in 38 southern highbush blueberry genotypes. Additionally, we assessed pollinator visitation frequency and foraging behavior over two growing seasons. Several statistical models were tested to optimize the prediction of pollinator visitation and pollination success, including partial least squares, BayesB, ridge-regression, and random forest.ResultsRandom forest models obtained high predictive abilities for pollinator visitation frequency, with values of 0.54, 0.52, and 0.66 for honey bee, bumble bee, and total pollinator visits, respectively. The BayesB model provided the most consistent prediction of fruit set, fruit weight, and seed set, with predictive abilities of 0.07, -0.08, and 0.42, respectively. Variable importance analysis revealed that genotypic differences in nectar volume had the greatest impact on honey bee and bumble bee visitation, although preferences for flower morphological traits varied depending on the foraging task. Flower density was a major driving factor attracting nectar-foraging honey bees and bumble bees, while pollen-foraging bumble bees were most influenced by flower accessibility, specifically corolla length and the length-to-width ratio.ConclusionsHoney bees comprised the majority of pollinator visits, and were primarily influenced by nectar volume and flower density. Corolla length and the length-to-width ratio were also identified as the main predictors of fruit set, fruit weight, seed count, as well as pollen-foraging bumble bee visits, suggesting that these bees and their foraging preferences may play a pivotal role in fruit production. Moderate to high narrow-sense heritability values (ranging from 0.30 to 0.77) were obtained for all floral traits, indicating that selective breeding efforts may enhance cultivar attractiveness to pollinators.

Elucidation of the genetic architecture of water absorption capacity in hard winter wheat through genome wide association study.

Water absorption capacity (WAC) influences various aspects of bread making, such as loaf volume, bread yield, and shelf life. Despite its importance in the baking process and end-product quality, its genetic determinants are less explored. To address this limitation, a genome-wide association study was conducted on 337 hard wheat (Triticum aestivum L.) genotypes evaluated over 5 years in multi-environmental trials. Phenotyping was done using the solvent retention capacity (SRC) test with water (SRC-water), sucrose (SRC-sucrose), lactic acid (SRC-lactic acid), and sodium carbonate (SRC-carbonate) as solvents. Individuals were genotyped using genotyping-by-sequencing to detect single nucleotide polymorphisms across the wheat genome. To detect the genomic regions that underline the SRCs and gluten performance index (GPI), a genome-wide association study was performed using six multi-locus models using the mrMLM package in R. Adjusted means for SRC-water ranged from 54.1% to 66.5%, while SRC-carbonate exhibited a narrow range from 84.9% to 93.9%. Moderate to high genomic heritability values were observed for SRCs and GPI, ranging from h2=0.61 to 0.88. The genome-wide association study identified a total of 42 quantitative trait nucleotides (QTNs), of which five explained over 10% of the phenotypic variation (R2 ≥ 10%). Most of the QTNs were detected on chromosomes 1A, 1B, 3B, and 5B. Few QTNs, such as S1A_5190318, S1B_3282665, S4D_472908721, and S7A_37433960, were located near gliadin, glutenin starch synthesis, and galactosyltransferase genes. Overall, these results show WAC to be under polygenic genetic control, with genes involved in the synthesis of key flour components influencing overall water absorption.

Adaptation Test and Genetic Parameters Estimation of Chili (Capsicum spp.) by Automation Drip Irrigation System in UG Technopark, Cianjur

Bean stew efficiency in 2019-2021 is vacillated because of the utilization of improper assortments and ecological variable. This study plans to decide assortments that have ideal development and creation at UG Technopark and to decide the hereditary variety between bean stew assortments. This study used a Randomized Complete Block Design (RCBD) with three blocks and one factor made up of eight chili varieties. The information examination utilized in this review was investigation of varians (ANOVA) at 5 and 1% level and the post hoc test utilized Duncan's Various Reach Test at 5%. Noticed information additionally were broke down utilizing coefficient of hereditary difference, coefficient of phenotypic change and heritability examination. The results showed that the Bonita variety has the highest plant height, dichotomous height, and the largest stem diameter. Bishop's crown variation had the biggest character of crown width, length and width of leaves meanwhile Ayesha variety had the fastest flowering time. On the fruit characters, Bishop’s crown variety had the highest fruit weight per plant and fruit diameter. Reisa varieties had the highest fruit weight. Each character had a wide range of genetic coefficients of variation with values ranging from 16.50 to 77.96%, high phenotypic coefficents of variation with values ranging from 13.93 to 86.38% and high broad meaning heritability values ranging from 0.43 to 1.00.

Effect of heat stress on semen characteristics and genetics in Thai native grandparent roosters

Grandparent roosters are crucial in poultry breeding programs and significantly influence future bird generations' genetic makeup and performance. However, these roosters face considerable challenges from heat stress, which can adversely affect their reproductive performance, semen quality, and overall health and welfare. Our study aimed to investigate the effects of heat stress on the genetics of semen characteristics, identify the appropriate temperature and humidity indices (THI), and determine the threshold point of heat stress to prevent thermal stress. We analyzed data from 3,895 records of 242 Thai native grandparent roosters in conjunction with the THI using 7 THI functions and the regression method. The threshold point of heat stress, genetic parameters, rate of decline of semen characteristics per level of THI, estimated breeding values and selection index values were analyzed using the multivariate test-day model in the AIREML and BLUPF90 programs. Based on the regression coefficient and statistical criteria of the lowest -2logL and AIC values, the results showed that a THI of 78 was considered the threshold point of heat stress. The estimated heritability values ranged from 0.023 to 0.032, 0.066 to 0.069, 0.047 to 0.057, and 0.022 to 0.024 for mass movement, semen volume, sperm concentration, and the semen index, respectively. The reduction rates of mass movement, semen volume, sperm concentration, and semen index at a THI of 78 were -0.009, -0.003, -0.170, and -0.083 per THI, respectively. The genetic correlations among the semen traits were moderately to strongly positive and ranged from 0.562 to 0.797. The genetic correlations between semen traits and heat stress were negative and ranged from -0.437 to -0.749. The permanent environmental correlations among the semen traits (0.648-0.929) were positive and greater than the genetic correlations. Permanent environmental correlations between semen traits and heat stress were negative and ranged from -0.539 to -0.773. The results of the selection indices showed that the higher the selection intensity was, the greater the degree to which the selection index corresponded to genetic progress. The recommendation for animal genetic selection is that the top 10% is appropriate because it seems most preferred. Therefore, using a multivariate test-day model and selection index for the high genetic potential of semen traits and heat tolerance in Thai native grandparent roosters makes it possible to achieve genetic assessment in a large population.

Physiological and antioxidant responses of synthetic hexaploid wheat germplasm under drought

BackgroundAs a result of the world population and climate change impact increases (especially in arid environments), there is a critical need for high-yield, drought-tolerant wheat. Synthetic hexaploid wheat derived lines (SHW-DL), were created artificially by crossing different durum wheat cultivars (AABB) with accessions of Aegilops tauschii (DD), a beneficial source of new genes for common bread wheat (Triticum aestivum L). Here, we studied the response of a panel of 91 SHW-DL for drought tolerance based on physiological, antioxidant enzyme activities, and drought tolerance indices.ResultsA wide range of variation and high values of heritability observed for grain yield, physiological and antioxidant traits indicating that the SHW-DL panel constitutes a valuable gene source for drought tolerance improvement of wheat. Despite decreases in grain yield (YLD), leaf area index (LAI), and relative water content (RWC) an increase in the content of malondialdehyde (MDA) was observed. Moreover, drought streass increased the antioxidant enzyme activities of ascorbate peroxidase (APX), catalase (CAT) and peroxidase (POD), and also photosynthetic pigments, proline (Pro), and MDA content. With higher values of grain yield, physiological and biochemical traits such as photosynthetic pigments, and RWC, and lower content of MDA, and peroxidase (H2O2) activity, SHW-DL performed better compared to common wheat lines under water stress conditions.ConclusionsDifferent responses to water stress within the germplasm and between synthetic and common wheat suggest that selection for adaptive and suitable genotypes is possible for drought tolerance in synthetic wheat germplasm. Genotypes 54, 98, 102, 105, 122, 124, 143, 159, 196, and 198 were identified to be directly used in breeding programs or indirectly by crossing them with other wheat germplasm collections.

Parameter genetik padi beras merah (Oryza sativa L.) yang ditanam pada lahan kering dengan sistem gogo

Crossing of F2BC4P19-36 promising line with IPB 3S variety resulted in red rice strains. These strains were selected until obtaining the F5 generation. The research aimed to determine the genetic diversity, heritability values, and genotypic correlation coefficients among quantitative traits for yield of red rice strains in dryland with a continuous cropping system. The study was conducted from May to September 2023 in Tampak Siring Village, Batukliang, Central Lombok Regency, West Nusa Tenggara. It employed a Randomized Complete Block Design (RCBD) with 14 genotypes, replicated three times, totaling 42 treatments. Data analysis was performed using Analysis of Variance (ANOVA) at a 5% significance level. Genetic diversity, assessed broadly, was indicated by traits such as the number of unproductive tillers, number of filled grains, and number of unfilled grains; moderately by traits such as number of productive tillers, total tillers, 100-grain weight, and grain weight per panicle; and narrowly by traits such as plant height, panicle length, flowering duration, and harvesting period. Heritability values were high for yield, moderate for total tillers, number of filled and unfilled grains, 100-grain weight, and flowering duration, and low for traits like plant height, number of productive and unproductive tillers, panicle length, grain weight per panicle, and harvesting period. Genotypic correlation coefficients showed positive associations with yield for traits such as panicle length, grain weight per panicle, and flowering duration, whereas negative correlations were observed with yield for the number of unproductive tillers. Genetic diversity, heritability values, and correlation coefficients serve as determinants for selection criteria

Generation Mean Analysis for Estimating Gene Action, Heterosis and Inbreeding Depression in Yield and Foliar Disease Resistance in Three Faba Bean (Vicia faba L.) Crosses

This study was conducted at the Sakha Agricultural Research Station farm over three growing seasons (2019/20, 2020/21, and 2021/22) to introduce new faba bean genotypes possessing high yield potential and increased resistance to foliar diseases. The research involved six populations (P1, P2, F1, F2, BC1, and BC2) from three crosses (Cross-1: Santamora x Foal Sbai Labiade, Cross-2: Santamora x Misr 3, and Cross-3: Cairo 4 x Misr 3), analyzed using a randomized complete block design with three replications. Generation mean analysis revealed significant mid and better parent heterosis for most traits, indicating over-dominance. Inbreeding depression manifested negatively for chocolate spot and rust diseases but positively for seed count and seed yield per plant across all crosses. Non-allelic interactions were present for all traits, and dominance gene effects were more influential than additive gene effects for most traits. Mean performance analysis showed that F1 populations had lower disease reactions, but higher yields compared to the better parent, while F2 populations displayed greater genetic variability due to segregation. Heterosis was significant for yield and its components across all crosses but less beneficial for disease resistance. Inbreeding depression was significant and negative for disease reactions but positive for yield traits. The study found high broad-sense heritability for all traits, suggesting potential for phenotypic selection. Narrow-sense heritability values were moderate for qualitative traits and lower for quantitative traits. Genetic advance under selection indicated the highest gains were associated with moderate heritability values. Significant non-allelic interactions suggested the need for specific breeding strategies, with dominance gene effects more pronounced than additive effects. These findings support the feasibility of selecting high-yielding, disease-resistant faba bean genotypes through targeted breeding methods, aligning with previous research on the genetic inheritance of these traits.

Identification of candidate single-nucleotide polymorphisms (SNPs) and genes associated with sugarcane leaf scald disease

Leaf scald, caused by Xanthomonas albilineans, is a severe disease affecting sugarcane worldwide. One of the most practical ways to control it is by developing resistant sugarcane cultivars. It is essential to identify genes associated with the response to leaf scald. A panel of 170 sugarcane genotypes was evaluated for resistance to leaf scald in field conditions for 2 years, followed by a 1-year greenhouse experiment. The phenotypic evaluation data showed a wide continuous distribution, with heritability values ranging from 0.58 to 0.84. Thirteen single nucleotide polymorphisms (SNPs) were identified, significantly associated with leaf scald resistance. Among these, eight were stable across multiple environments and association models. The candidate genes identified and validated based on RNA-seq and qRT-PCR included two genes that encode NB-ARC leucine-rich repeat (LRR)-containing domain disease-resistance protein. These findings provide a basis for developing marker-assisted selection strategies in sugarcane breeding programs.