High Heritability Research Articles

Cross potential selection: a proposal for optimizing crossing combinations in recurrent selection using the usefulness criterion of future inbred lines.

In plant breeding programs, rapid production of novel varieties is highly desirable. Genomic selection allows the selection of superior individuals based on genomic estimated breeding values. However, it is worth noting that superior individuals may not always be superior parents. The choice of the crossing pair significantly influences the genotypic value of the resulting progeny. This study has introduced a new crossing strategy, termed cross potential selection, designed to expedite the production of novel varieties of inbred crops. Cross potential selection integrates fast recurrent selection and usefulness criterion to generate novel varieties. It considers the segregation of each crossing pair and computes the expected genotypic values of the top-performing individuals, assuming that the progeny distribution of genotypic values follows a normal distribution. It does not consider genetic diversity and focuses only on producing a novel variety as soon as possible. We simulated a 30-year breeding program in 2 scenarios, low heritability (h2=0.3) and high heritability (h2=0.6), to compare cross potential selection with 2 other selection strategies. Cross potential selection consistently demonstrated the highest genetic gains among the 3 strategies in early cycles. In the 3rd year of the breeding program with a high heritability (h2=0.6), cross potential selection exhibited the highest genetic gains, 138 times that of 300 independent breeding simulations. Regarding long-term improvement, the other selection strategies outperformed cross potential selection. Nevertheless, compared with the other 2 strategies, cross potential selection achieved significant short-term genetic improvements. Cross potential selection is a suitable breeding strategy for the rapid production of varieties within limited time and cost.

Unraveling Promising Genetic Variability Associated with Strong Culm and Yield Parameters in Inter Sub-Specific Cross Derived Recombinant Inbred Lines in Rice (Oryza sativa L.)

Strengthening the rice culm through genetic improvement has been an important target in breeding to abate the lodging problem in rice. The present investigation was attempted to study the variability, genetic parameters and trait association in recombinant inbred lines (RILs) derived from inter sub-specific cross of elite indica mega variety ‘Swarna’ and Tropical japonica strong culm accession ‘IRGC 39111’. Analysis of Variance (ANOVA) displayed significant variation in RILs for all the traits studied. The investigation revealed high estimates of GCV and PCV along with high heritability and genetic advance as percent of mean (GAM) for all culm strength (CS) traits revealing the role of additive gene effect and selection of these traits shall be effective in rice improvement. Correlation studies revealed that the internode breaking weight (IBW) and bending moment at breaking(M) had a high significant positive correlation with all the CS traits, panicle weight and grain yield. Thus, the direct selection of positively associated traits can improve the lodging resistance in rice. The principal component analysis (PCA) showed that, seven principal components (PCs) out of 23 traits attributed approximately 92.9% of the total cumulative variability. The traits culm thickness (CT), Internode breaking weight (IBW), section modulus (SM), bending stress (BS), Bending moment at breaking (M) contributed maximum to the total diversity and the lines with higher trait values for the aforementioned traits could be utilized as donors to improve the culm strength and its attributing traits in future breeding programs. From this study, it is evident that tropical japonica lines can be a great source of genetic diversification for rice improvement.

Maximizing growth without compromising wood density: Selecting superior Norway spruce clones

The study examined a free-growing (initial stand density 400 trees ha–1), 50-year-old grafted clonal Norway spruce plantation in Eastern Latvia to assess the genetic control and variability of growth traits and wood density. The latter was used as a proxy for structural timber strength. Results showed moderately high heritability in growth traits and moderate variability in wood density among clones, with an estimated genetic coefficient of variation CVg, of 8.6%. Even when grown at a very low density on nutrient-rich soil, 85% of the trees met the density requirements for construction timber (C18 in accordance with EN 338). The negative correlation between growth traits and wood density was weak at both individual tree and clonal levels (–0.08 < rP < –0.06; –0.16 < rG < –0.09), making it feasible to select fast-growing clones with wood density required for structural timber. The observed variation underscores the importance of selective breeding to ensure optimal timber quality, with implications for enhancing sawn wood strength grades and promoting climate-resilient forestry practices. Keywords: tree breeding; structural timber; clonal forestry; wood properties; plantation forestry; climate-smart forestry

Assessment of Heritability and Genetic Advance for Yield and Yield Related Traits under Different Dates of Sowing of Bread Wheat (Triticum aestivum L.)

Wheat (Triticum aestivum L.) is a self-pollinating annual plant extensively grown as staple food source in the world. Information on the extent of heritability and genetic advance among different traits of bread wheat genotypes is essential to designing breeding strategies with the objective to estimate heritability and genetic advance for different characters of bread wheat genotypes. A total of 10 bread wheat genotypes were evaluated for 15 traits sown, three at different dates in 10 days interval The first on 30 November 2022, second on 10 December 2022, and third 20 December 2022 in a Randomized Block Design with three replications at Student Instruction Farm, C.S. Azad University of Agriculture and Technology, Kanpur-208002 (U.P.) during Rabi, 2022-23. in Randomized Block Design. High PCV and GCV were observed from biological yield, grain yield, plant height and productive tiller per plant high heritability estimate were recorded for grain yield per plant followed by biological yield per plant, plant height, days to 50% heading, days to maturity, number of productive tillers per plant, 1000-grain weight and number of grains per ear in both generations on individual and grain yield per plant followed by biological yield, number of productive tillers per plant, plant height, seed hardness, days to maturity in both generations on pooled basis. High genetic advance was observed for grain yield per plant and biological yield per plant in both the generation; seed hardness, number of productive tillers per plant in F1 generation and grain yield per plant and biological yield per plant in both the generation on pooled basis. Consequently, since additive gene action controls the phenotypic manifestation of certain features, those traits should receive special attention in wheat breeding programs. Grain yield will therefore be increased by direct selection for these features.

313 Many farmers want a prediction of future performance, not necessarily breeding potential

Abstract High heritability is a characteristic of many performance traits in cattle translating to a relatively strong correlation between an (accurate) estimated breeding value for an animal and its (future) production potential. However, the broad sense heritability (i.e., numerator in the formula includes both additive and non-additive genetic variance) is often larger than the narrow sense heritability (i.e., numerator includes only the additive genetic variance) especially for low heritability traits like reproductive performance. Moreover, the repeatability of a trait can be greater again, the difference between the heritability and repeatability is the inclusion of a permanent environmental variance in the numerator. Accurate and pertinent omic-based animal-level features can contribute to an increase in narrow sense heritability owing to a possible reduction in the residual variance; such data can also provide insights into both non-additive genetic variance and the permanent environmental variance. Even at the level of the contemporary group, omic-level data from the likes of bulk blood/saliva/milk sample, can improve how systematic environmental effects are modeled in the mixed model equations thus also reducing the residual variance. The greater heritability will contribute to a strengthening of the correlation between future phenotypic performance potential and estimated additive genetic merit. Importantly, omic measures for individual animals can help predict the permanent environmental effect of that animal capturing the yet untapped contributor to phenotypic variance. Irrespective, predictions need to be replaced by prescriptions; end users are inundated with data yet crave actionable information. Animal breeders have a lush (pardon the pun!) history of distilling estimates of genetic merit for a plethora of traits into a single value per animal (i.e., breeding indexes); this is the first step in transitioning from predictions to prescriptions. Given the familiarity of end users with breeding indexes, the potential exists to develop production indexes to rank commercial animals on future expected performance taking cognizance of genetic and non-genetic effects. Such production indexes align well with the associated breeding index but where the estimates of genetic merit for the traits in question are replaced by estimates of production merit; these estimated production values are the sum of the additive genetic, non-additive genetic and permanent environmental effects. The weighting factors in the production indexes are more short-term using current costs and prices as opposed to breeding indexes which are longer term. In comparison with the breeding indexes, the production indexes can include ancillary information like gender, age, and month of calving/birth. Like breeding indexes, they are updated in real time. Examples of the application of genome-enabled production indexes are guides for valuing animals for purchase or culling.

Genomic evaluation for body weight, length and growth estimates in meagre Argyrosomus regius

Meagre (Argyrosomus regius) is a fast-growing sciaenid species which recently received a rising interest in aquaculture diversification and industry sustainability. The present study illustrates the first complete genomic evaluation of meagre for body weight, length and growth parameters using 810 offspring genotyped with a double-digest RAD sequencing approach. Offspring were assigned to both parents using SNP markers and a QTL associated with growth explaining approximately 3.25 % of the phenotypic variance was found. Using pedigree and genomic relationship matrix, moderate to high heritability estimates along with high genetic/genomic correlations between all studied traits were detected with the exception of the initial body weight. The predicted ability of the breeding values was higher using the genomic than the pedigree relationship matrix for body weight and growth. Present findings provide a better genetic insight of the production traits, as well as evidence that the implementation of the genomic information in breeding programs could be beneficial for the parental assignment as well as for the aquaculture production increase through genetic improvement using marker assisted or genomic selection.

Early exposure to phosphorus starvation induces genetically determined responses in Sorghum bicolor roots

Key message We identified novel physiological and genetic responses to phosphorus starvation in sorghum diversity lines that augment current knowledge of breeding for climate-smart crops in Europe.Phosphorus (P) deficiency and finite P reserves for fertilizer production pose a threat to future global crop production. Understanding root system architecture (RSA) plasticity is central to breeding for P-efficient crops. Sorghum is regarded as a P-efficient and climate-smart crop with strong adaptability to different climatic regions of the world. Here we investigated early genetic responses of sorghum RSA to P deficiency in order to identified genotypes with interesting root phenotypes and responses under low P. A diverse set of sorghum lines (n = 285) was genotyped using DarTSeq generating 12,472 quality genome wide single-nucleotide polymorphisms. Root phenotyping was conducted in a paper-based hydroponic rhizotron system under controlled greenhouse conditions with low and optimal P nutrition, using 16 RSA traits to describe genetic and phenotypic variability at two time points. Genotypic and phenotypic P-response variations were observed for multiple root traits at 21 and 42 days after germination with high broad sense heritability (0.38–0.76). The classification of traits revealed four distinct sorghum RSA types, with genotypes clustering separately under both low and optimal P conditions, suggesting genetic control of root responses to P availability. Association studies identified quantitative trait loci in chromosomes Sb02, Sb03, Sb04, Sb06 and Sb09 linked with genes potentially involved in P transport and stress responses. The genetic dissection of key factors underlying RSA responses to P deficiency could enable early identification of P-efficient sorghum genotypes. Genotypes with interesting RSA traits for low P environments will be incorporated into current sorghum breeding programs for later growth stages and field-based evaluations.

Use of Phenomics in the Selection of UAV-Based Vegetation Indices and Prediction of Agronomic Traits in Soybean Subjected to Flooding

Flooding is a frequent environmental stress that reduces soybean growth and grain yield in many producing areas in the world, such as the United States, Southeast Asia, and Southern Brazil. In these regions, soybean is frequently cultivated in lowland areas in crop rotation with rice, which provides numerous technical, economic, and environmental benefits. In this context, the identification of the most important spectral variables for the selection of more flooding-tolerant soybean genotypes is a primary demand within plant phenomics, with faster and more reliable results enabled using multispectral sensors mounted on unmanned aerial vehicles (UAVs). Accordingly, this research aimed to identify the optimal UAV-based multispectral vegetation indices for characterizing the response of soybean genotypes subjected to flooding and to test the best linear model fit in predicting tolerance scores, relative maturity group, biomass, and grain yield based on phenomics analysis. Forty-eight soybean cultivars were sown in two environments (flooded and non-flooded). Ground evaluations and UAV-image acquisition were conducted at 13, 38, and 69 days after flooding and at grain harvest, corresponding to the phenological stages V8, R1, R3, and R8, respectively. Data were subjected to variance component analysis and genetic parameters were estimated, with stepwise regression applied for each agronomic variable of interest. Our results showed that vegetation indices behave differently in their suitability for more tolerant genotype selection. Using this approach, phenomics analysis efficiently identified indices with high heritability, accuracy, and genetic variation (>80%), as observed for MSAVI, NDVI, OSAVI, SAVI, VEG, MGRVI, EVI2, NDRE, GRVI, BNDVI, and RGB index. Additionally, variables predicted based on estimated genetic data via phenomics had determination coefficients above 0.90, enabling the reduction in the number of important variables within the linear model.

Genetic Variance in Heparan Sulfation Is Associated With Salt Sensitivity.

High heritability of salt sensitivity suggests an essential role for genetics in the relationship between sodium intake and blood pressure (BP). The role of glycosaminoglycan genes, which are crucial for salinity tolerance, remains to be elucidated. Interactions between 54 126 variants in 130 glycosaminoglycan genes and daily sodium excretion on BP were explored in 20 420 EPIC-Norfolk (European Prospective Investigation Into Cancer in Norfolk) subjects. The UK Biobank (n=414 132) and the multiethnic HELIUS study (Healthy Life in an Urban Setting; n=2239) were used for validation. Afterward, the urinary glycosaminoglycan composition was studied in HELIUS participants (n=57) stratified by genotype and upon dietary sodium loading in a time-controlled crossover intervention study (n=12). rs2892799 in NDST3 (heparan sulfate N-deacetylase/N-sulfotransferase 3) showed the strongest interaction with sodium on mean arterial pressure (false discovery rate 0.03), with higher mean arterial pressure for the C allele in high sodium conditions. Also, rs9654628 in HS3ST5 (heparan sulfate-glucosamine 3-sulfotransferase 5) showed an interaction with sodium on systolic BP (false discovery rate 0.03). These interactions were multiethnically validated. Stratifying for the rs2892799 genotype showed higher urinary expression of N-sulfated heparan sulfate epitope D0S0 for the T allele. Conversely, upon dietary sodium loading, urinary D0S0 expression was higher in participants with stable BP after sodium loading, and sodium-induced effects on this epitope were opposite in individuals with and without BP response to sodium. The C allele of rs2892799 in NDST3 exhibits higher BP in high sodium conditions when compared with low sodium conditions, whereas no differences were detected for the T allele. Concomitantly, both alleles demonstrate distinct expressions of D0S0, which, in turn, correlates with sodium-mediated BP elevation. These findings underscore the potential significance of genetic glycosaminoglycan variation in human BP regulation.

Phenotypic Diversity of Released South African Bred Potato Varieties for Tuber Yield and Processing Quality

Abstract Potato (Solanum tuberosum L.) is a nutritious starchy tuber crop consumed as a staple food in most potato growing countries. Its productivity and production are limited by climate change; thus, it is of utmost importance to tap into the diversity of germplasm resources, therefore, diversifying the potato varieties available for production. The objectives of this study were to determine the phenotypic diversity among the selected Agricultural Research Council-Vegetable, Industrial and Medicinal Plants (ARC-VIMP) potato varieties for tuber yields and processing quality and to determine the correlation between measured traits. Two imported and 22 local potato varieties were planted in three different environments in South Africa. Significant (P < 0.001) differences in the tested varieties across all environments were observed for all measured traits. High broad-sense heritability (> 0.6) was observed for most of the traits, except for fry colour and the yield of unmarketable tubers. Nine ARC varieties and three standard varieties were associated with high tuber yield and quality traits, indicating their suitability for the fresh market and processing industry. Variety Mondial and five ARC varieties were associated with high tuber yield, indicating their suitability for the fresh market. Varieties released between 2004 and 2021 had high tuber yield, dry matter and specific gravity compared to the standard varieties and varieties released between 1980 and 1999, although there were slight differences in the magnitudes of their traits measured. These varieties could be recommended for commercial production for specific markets and for use as potential parents for further genetic improvement of the potato crop.

Scouting rice (Oryza sativa L.) landraces for moisture stress tolerance using morphometric diversity analysis

Climate-change is a major threat to sustainable agriculture. Rice is one of the staple food grains that sustain 2/3rd of global population. Therefore, developing climate-resilient rice genotypes to combat moisture stress and other climate change factors are most important to address the challenges posed by climate change. The vast availability of genetic variance among the rice genotypes for different traits favours the selection of desirable donor parents. A field investigation was carried out to characterize 21 traditional rice landraces under induced moisture stress in 2 environments including induced moisture stress (S) and non-stress (NS). The response to the varied level of environments was observed in terms of biometric and yield parameters followed by multivariate analysis and variability analysis. The study revealed higher phenotypic-coefficient of variation (PCV) and genotypic-coefficient of variation (GCV) for plant height and single plant yield in both environments. High heritability was also recorded in the moisture stressed environment for plant height (98.63 %), single plant yield (98.19 %) and productive tillers (95.12 %), whereas under NS, the heritability is more for single plant yield only (99.56 %). The genotypes formed nine clusters under the S environment, based on the Euclidean distance, of which the three CMS lines segregated in cluster III distinctly. The principal component analysis exhibited three principal components with a cumulative variance of 86.13 % and 86.40 % in the NS and S environments respectively. The traits such as days to 50 % flowering, panicle height, panicle length, grains per panicle, productive tillers, thousand-grain weight and single plant yield were the positive contributors. Spikelet fertility (%) and harvest index were positively correlated with seed yield per plant. Path-coefficient analysis was significant for grain yield, harvest index, spikelet fertility, pollen fertility and plant height and positively influenced by productive tillers plant-1. The study concluded the prospect of using Mattaikar, Rajalakshmi, Mallikar and Kuliyadichan as potential donors for developing upland rice with moisture stress resilience.

Genetic parameter estimation and genetic evaluation of important economic traits in white and yellow broilers

ABSTRACT 1. This study calculated descriptive statistics for the production traits of two broiler populations: 1) the Northeast Agricultural University broiler lines divergently selected for abdominal fat content (NEAUHLF white broilers), including fat and lean lines; and 2) the Guangxi yellow broilers. Their genetic parameters were estimated, including (co)variance components, heritability (h 2 ) and genetic correlations (rg), using the REML method. 2. Heritability estimates (h 2 ) for NEAUHLF white broilers ranged from 0.07 to 0.61. Traits with high heritability (h 2 >0.3) included body weight at 3, 5 and 7 weeks of age (BW3, BW5, BW7), carcass weight (CW), metatarsal circumference (MeC), liver weight (LW), gizzard weight (GW), spleen weight (SW) and testis weight (TeW), while in Guangxi yellow broilers, heritability estimates ranged from 0.18 to 0.76, with every trait exhibiting high heritability, except for SW (0.18). 3. Positive genetic correlations for NEAUHLF were found (rg >0.3, ranging from 0.31 to 0.84) between BW7 and metatarsal length (MeL), MeC, body oblique length (BoL), chest angle (ChA), LW, GW, heart weight (HW) and SW. Genetic correlations between abdominal fat weight (AFW) and BW1, BW3, BW5, CW, MeL, keel length (KeL), BoL and LW were positive (rg >0.3, ranging from 0.31 to 0.58). 4. Among the Guangxi population, BW (125 d of age) showed strong positive genetic correlations with all other traits (rg >0.3, ranging from 0.30 to 0.99), while AFW displayed strong positive genetic correlations with leg muscle weight (LeW), CW, BW and thigh diameter (TD) (rg >0.3, ranging from 0.44 to 0.51). 5. It was concluded that the characteristics of the two populations were different, which means there is a need to use different strategies when performing the breeding work to improve productivity and efficiency in both broiler populations.

Genetic diversity and morphological characterization of different Adenium genotypes

The current study at Tamil Nadu Agricultural University in 2023–2024 aims to characterize the morphological features and genetic diversity of 20 Adenium genotypes. The research was performed with various vegetative and floral traits, revealing significant variations among genotypes. Notable differences were observed in plant height, branching habit, caudex circumference, leaf characteristics and floral features. Genetic analysis showed high genotypic and phenotypic coefficients of variation for traits like petal thickness, number of branches per plant and diameter of the corolla tube. These traits also exhibited high heritability and genetic advance, indicating potential for improvement through selective breeding. Other traits, such as plant height and leaf dimensions, showed moderate heritability and lower genetic advance, suggesting the influence of non-additive gene action and environmental factors. Principal component analysis identified seven principal components accounting for 85.178 % of the total variation. The first 2 components explained 40.59 % of the variability, with plant height, number of branches, flower diameter and length of anther appendages contributing significantly to PC1, while leaf width, length of corolla tube and flower weight were major contributors to PC2. This study provides valuable insight into the genetic architecture of Adenium traits, offering a foundation for future breeding efforts aimed at developing improved varieties for commercial and ornamental purposes. These findings highlight the potential for genetic improvement in Adenium through selective breeding, particularly for traits with high heritability and genetic advance.

Assessment of Genetic Variability for Yield and Yield Related Traits in Safflower Core Subset Germplasm

One hundred and fifty safflower genotypes of Core subset germplasm provided by ICAR-IIOR, were evaluated to study genetic variability, correlation and principal component analysis (PCA). A wide range of phenotypic data with near normal distribution was observed for most of the traits analysed. High variability was observed for all the traits studied indicating diverse nature of the germplasm. Significant positive correlation was observed for seed yield with test weight and oil content. Genotype GMU 6869 has been identified as potential genotype surpassing the best check A1 for seed yield and earliness. Twenty three genotypes significantly superior to the 2nd best check PBNS-12 were identified. High heritability along with GAM was recorded for the traits number of effective capitula/plant, test weight and single plant yield indicating that these characters may be considered as selection criteria for genetic improvement in safflower. Principal component analysis revealed that first four principal components contributed 65.2% of total variance. PCA-variables plot and PCA Bi-plots revealed that two traits viz., LPB and HPB contributed maximum variations in PC1, while two traits viz., DAF & DAM contributed to the maximum variability in PC-2. Safflower accessions displaying highest performance for the traits studied were identified. These genotypes can be used as parental lines for improvement of specific traits in safflower breeding program.

Unveiling the genetic potential of Terminalia chebula Retz. accessions from North-East and South India: A morphometric analysis

This study examined genetic diversity and growth performance of thirty Terminalia chebula genotypes from various regions of India. Seedlings were evaluated for growth attributes over 180 days after transplanting (DAT). Significant variations were observed across accessions for traits like shoot length, root length, collar diameter and volume. MHTC 04 showed superior performance, with maximum shoot length (36.23 cm) and root length (38.47 cm) at 180 DAT. KETC 05 exhibited the highest collar diameter (1.08 cm) and volume index (39.35) at 180 DAT. The genetic analysis revealed low to moderate PCV and GCV for most traits. Volume index showed the highest PCV (47.31 %) and GCV (47.23 %). High heritability (>95 %) was observed for several traits viz., root length, collar diameter and volume index. Path coefficient analysis identified collar diameter and shoot fresh weight as having the strongest positive direct effects on quality index. Cluster analysis grouped 30 genotypes into 10 clusters with cluster II being the largest (8 progenies). Quality index contributed the maximum (59.30 %) towards divergence followed by shoot dry weight (13.94 %) and volume index (8.28 %). This study identified promising genotypes and important traits for T. chebula improvement programmes, highlighting the potential for selective breeding to enhance the seedling quality and growth performance.

Update on Antisocial Personality Disorder.

Antisocial personality disorder (ASPD) is a characterized by lifelong or recurrent behavioral problems that begin in childhood or early adolescence. This communication provides an overview on ASPD including findings from recent reviews and new research. With regard to DSM-5's Section III Alternative Model of Personality Disorder criteria for ASPD, advocates point to the broader symptom coverage and harmonization with ICD-11; yet critics point to the lack of evidence for improved outcomes. A new report shows that antisocial individuals age faster than non-antisocial peers. ASPD has high heritability and newer molecular studies have found intriguing linkages to genes associated with crucial brain regions. A mentalization-based therapy model has been developed and early work shows promise. ASPD is common, widespread, and disruptive to individuals, families, and society. Chronic and lifelong, ASPD typically lessens in severity with advancing age. Assessment rests on the individual's history because there are no diagnostic tests. ASPD likely results from an interplay ofgenetic and environmental factors. Brain imaging studies have linked cortical dysfunction to antisocial behavior in crucial brain regions. Medication is sometimes targeted at the individual's aggression and irritability, but a more rational approach is to target co-occurring disorders. Cognitive-behavioral therapy and mentalization-based therapy models have been developed and are being studied.

Assessing Heat Stress Tolerance of Wheat Genotypes through Integrated Molecular and Physio-Biochemical Analyses

Heat as an abiotic stress significantly impairs the sustainable productivity of wheat (Triticum aestivum L.). To determine the tolerance of genotypes to heat stress, a comprehensive approach should be used that integrates simultaneous phenotyping and genotyping analyses. The aim of this study is to identify local heat-tolerant genotypes using simple sequence repeat (SSR) markers and evaluate the selected genotypes under field conditions for their tolerance to heat stress. Of the 12 SSR markers that showed polymorphism, eight were associated with six important traits. The use of hierarchical cluster analysis (HC) based on SSR markers led to the identification of 13 genotypes that showed varying results and were grouped into three distinct heat tolerance classes: tolerant (T), moderately tolerant (MT), and sensitive (S). The results showed that heat stress had a significant effect on 19 traits under this study, with significant variation in tolerance to heat stress between genotypes. The tolerant genotypes exhibited a range of average thousand-kernel weight (TKW) values between 40.56 and 44.85, while the sensitive genotype (Yecora Rojo) had an average TKW of 35.45. Furthermore, the tolerant genotypes showed two to three times higher levels of antioxidants compared to the sensitive genotypes when exposed to heat stress. Among the traits analyzed, six showed a favorable combination of high heritability (>60%) and genetic gain (>20%). Through the integration of principal component analysis and stepwise multiple linear regression, it was determined that six traits (grain yield, 1000-kernel weight, plant height, intercellular carbon dioxide, flag leaf area, and grain filling duration) revealed differences between the 13 genotypes. HC analysis of the six traits resulted in the same division of genotypes into three main categories as observed in an HC analysis based on SSR markers. It is worth noting that Saudi wheat, including KSU106, KSU105, and KSU115 as local genotypes, in addition to the 16HTWYT-22 genotype, showed higher heat tolerance compared to the other genotypes tested, indicating its potential suitability for agriculture in Saudi Arabia. These results contribute to breeding programs focused on developing heat-tolerant wheat varieties and accelerate progress in wheat productivity improvement programs.

Genome-wide association study of fiber quality traits in US upland cotton (Gossypium hirsutum L.).

A GWAS in an elite diversity panel, evaluated across 10 environments, identified genomic regions regulating six fiber quality traits, facilitating genomics-assisted breeding and gene discovery in upland cotton. In this study, an elite diversity panel of 348 upland cotton accessions was evaluated in 10 environments across the US Cotton Belt and genotyped with the cottonSNP63K array, for a genome-wide association study of six fiber quality traits. All fiber quality traits, upper half mean length (UHML: mm), fiber strength (FS: gtex-1), fiber uniformity (FU: %), fiber elongation (FE: %), micronaire (MIC) and short fiber content (SFC: %), showed high broad-sense heritability (> 60%). All traits except FE showed high genomic heritability. UHML, FS and FU were all positively correlated with each other and negatively correlated with FE, MIC and SFC. GWAS of these six traits identified 380 significant marker-trait associations (MTAs) including 143 MTAs on 30 genomic regions. These 30 genomic regions included MTAs identified in at least three environments, and 23 of them were novel associations. Phenotypic variation explained for the MTAs in these 30 genomic regions ranged from 6.68 to 11.42%. Most of the fiber quality-associated genomic regions were mapped in the D-subgenome. Further, this study confirmed the pleiotropic region on chromosome D11 (UHML, FS and FU) and identified novel co-localized regions on D04 (FU, SFC), D05 (UHML, FU, and D06 UHML, FU). Marker haplotype analysis identified superior combinations of fiber quality-associated genomic regions with high trait values (UHML = 32.34mm; FS = 32.73gtex-1; FE = 6.75%). Genomic analyses of traits, haplotype combinations and candidate gene information described in the current study could help leverage genetic diversity for targeted genetic improvement and gene discovery for fiber quality traits in cotton.

ESTIMATION OF GENETIC VARIABILITY, HERITABILITY, AND GENETIC ADVANCE FOR YIELD AND YIELD CONTRIBUTING CHARACTERS IN SORGHUM (SORGHUM BICOLOR L.)

The field experiment was conducted at the Experimental Farm of College of Agriculture, Latur, during Kharif – 2021–2022 with 26 genotypes of Sorghum, including three checks genotypes as PVK-1009-C, PVK-400-C, and PVK-809-C, with the goal of studying genetic variability, heritability, and genetic advance for yield and yield contributing characters in Sorghum (Sorghum bicolor L.). An analysis of variance involving 26 Sorghum genotypes for 12 quantitative characters revealed significant differences for all the traits under study indicating the presence of wide genetic variability in the experimental materials. Fodder yield per plant field grade score, plant height, grain yield per plant, threshed grade score, and test weight had a significantly high genotypic coefficient of variation (GCV) and phenotypic coefficient of variation magnitudes. The present investigation clarified that plant height, number of grains per primary, field grade score, threshed grade score, grain yield per plant, and fodder yield per plant these character have high heritability coupled with a high genetic advance and high GCV, indicating the role of additive genes in governing the inheritance of these traits, which could be improved through simple selection.

Abstract 72: Genetic variance in heparan sulfation is associated with salt-sensitivity: a gene-environment analysis in EPIC-Norfolk, UK biobank, and HELIUS

Background: High heritability of salt sensitivity suggests an essential role for genetics in the relationship between sodium intake and blood pressure (BP). The role of glycosaminoglycan (GAG) genes, which are crucial for salinity tolerance througout evolution, remains to be elucidated. Methods: Interactions between 54,126 variants in 130 GAG genes and daily sodium excretion on BP were explored in 20,420 EPIC-Norfolk subjects. UK Biobank (n=414,132) and the multi-ethnic HELIUS study (n=2,239, comprising a balanced representation of people from European, Subsaharan, South Asian, Turkish, and Moroccan descent) were used for validation. Afterwards, urinary GAG composition was studied in HELIUS participants (n=57) stratified by genotype, and upon dietary sodium loading in a time-controlled crossover intervention study (n=12). Results: rs2892799 (NDST3) showed the strongest interaction with sodium on mean arterial pressure (MAP) (FDR 0.03), with higher MAP for the C-allele in high sodium conditions. Also, rs9654628 (HS3ST5) showed an interaction with sodium on systolic BP (FDR 0.03). These interactions were multi-ethnically validated (figures A and B, respectively). Stratifying for rs2892799 genotype, showed higher urinary expression of N-sulfated heparan sulfate epitope D0S0 for the T-allele. Conversely, upon dietary sodium loading, urinary D0S0 expression was higher in participants with stable BP after sodium loading, and sodium-induced effects on this epitope were opposite in individuals with and without BP response to sodium. Conclusion: The C-allele of rs2892799 (NDST3) exhibits higher BP in high sodium conditions when compared to low sodium conditions, whereas no differences were detected for the T-allele. Concomitantly, both alleles demonstrate distinct expressions of D0S0, which, in turn, correlates with sodium-mediated BP elevation. These findings underscore the potential significance of genetic GAG variation in human BP regulation.