Hybrid Breeding Research Articles

Dynamic Niches-Based Hybrid Breeding Optimization Algorithm for Solving Multi-Modal Optimization Problem

Some problems exist in classical optimization algorithms to solve multi-modal optimization problems and other complex systems. A Dynamic Niches-based Improved Hybrid Breeding Optimization (DNIHBO) algorithm is proposed to address the multi-modal optimization problem in the paper. By dynamically adjusting the niche scale, it effectively addresses the issue of niche parameter sensitivity. The structure of the algorithm includes three distinct groups: maintainer, restorer, and sterile lines for updating operations. However, the maintainer individuals often stagnate, leading to the risk of the local optima. To overcome this, neighborhood search and elite mutation strategies are incorporated, enhancing the balance between exploration and exploitation. To further improve individual utilization within niches, a niche restart strategy is introduced, ensuring sustained population diversity. The efficacy of DNIHBO is validated through simulations on 16 multi-modal test functions, followed by comparative analyses with various multi-modal optimization algorithms. The results convincingly demonstrate that DNIHBO not only effectively locates multiple global optima but also consistently outperforms other algorithms on test functions. These findings underscore the superiority of DNIHBO as a high-performing solution for multi-modal optimization.

Genome-wide association study of growth and reproductive traits based on low-coverage whole-genome sequencing in a Chubao black-head goat population

The Chubao black-head goat is a novel hybrid breed that combines the advantages of Macheng black goats, such as good reproductive performance, strong adaptability, and resistance to rough feeding, with the superior growth and meat characteristics of Boer goats. Given the substantial economic importance of growth (such as birth weight, body height, body length, and chest circumference across different growth stages) and reproductive traits (particularly average litter size after first parity), the aim of this study was to identify significant SNPs and candidate genes associated with these traits in Chubao black-head goats. Through whole-genome sequencing (with 34 goats at approximately 15× coverage and 466 goats at approximately 1× coverage), genotype imputation, and quality control, 22,665,331 SNPs were identified and subsequently used for genetic analyses. Heritability estimates indicated that growth traits exhibit moderate to high heritability (ranging from 0.297 ± 0.071 to 0.535 ± 0.118), while reproductive traits demonstrated low to moderate heritability (with a value of 0.220 ± 0.108). By performing FarmCPU-based genome-wide association studies, we identified 48 potentially significant SNPs associated with growth traits and 7 with reproductive traits. Additionally, 85 candidate genes (such as COL14A1, ZNF148, and TTC39C) linked to growth traits were identified and enriched in pathways associated with fundamental molecular biological activities such as protein deubiquitination, regulation of mRNA stability, and the MAPK signaling pathway. Furthermore, 10 candidate genes (such as SOHLH2, CCNA2, and SOX7) associated with reproductive traits were identified and enriched in pathways related to specific reproductive processes such as oocyte differentiation, endoderm formation, and progesterone-mediated oocyte maturation. Overall, these findings provide valuable preliminary insights into the molecular mechanisms underlying growth and reproductive traits in Chubao black-head goats. However, further functional validation is needed to effectively use these potential SNPs and candidate genes in improving the breeding of these traits in this breed.

Comparative Analyses of Green Plantlet Regeneration in Barley (Hordeum vulgare L.) Anther Culture

The efficient doubled haploid (DH) plant production methods play a key role in accelerating the breeding of new varieties and hybrids in cultivated plants. Consequently, DH plant production methods are continuously improving for barley (Hordeum vulgare L.) breeding and research programs. Two plant regeneration (FHGR and K4NB) and three rooting media (MSr, N6I and ½N6I + Ca) were compared with four F1 barley cross-combinations to clarify the effect of medium on the regeneration of green and albino plantlets and acclimatization. The plant regeneration efficiency was higher using K4NB medium (74.53 green plantlets/100 anthers and 30.85 albino/100 anthers) compared to FHGR (55.77 green plantlets/100anthers and 21.32 albino/100 anthers). The percentage of acclimatization was highest when the K4NB regeneration medium was combined with the MSr rooting medium. Altogether, 61.83% of the anther culture-derived plantlets of 8 cross-combinations acclimatized to the greenhouse conditions, and 1403 acclimatized plantlets were produced from the F1 cross-combinations. Haploid (22.52%), diploid (69.37%) and tetraploid (8.11%) plantlets were identified among the 111 tested green plantlets by flow cytometric analyses. The tetraploid lines can be explored to offer new scopes for future barley research and breeding directions. Nearly one thousand DH plants have been integrated into our barley breeding program.

Comparative analysis of the growth differences between hybrid Ningdu Yellow chickens and their parentals

Although the local high quality chicken breed in China has excellent flavor, its growth rate is inferior to that of foreign breeds. To improve the growth rate of local chicken breeds, it is crucial to study the mechanism of chicken muscle development. Herein, Ningdu Yellow chicken was used as the research object, and a new hybrid breed (W) was obtained by crossing the G, H and D lines, which combined the excellent physiological characteristics of its parents. Combined analysis of Ningdu Yellow chickens and their parents was carried out. Chickens from 105-day-old lines (W, G, H) were selected, and breast meat and serum were extracted for transcriptome sequencing and metabolome determination to study their growth differences. The live weight, carcass weight, half-eviscerated weight, eviscerated weight, and breast muscle weight of W were significantly higher than those of G and H. Differential expression analysis identified 1700 differentially expressed genes (DEG), and gene ontology and kyoto encyclopedia of genes and genomes (KEGG) analyses identified 33 and 1 pathways related to growth and development and steroid biosynthesis, respectively. Next, pairwise analysis identified 57 KEGG pathways, among which the MAPK signaling, steroid hormone biosynthesis, tight junction, and PPAR signaling pathways were involved in growth and development. Cluster analysis found that genes highly expressed in the W group were associated with regulation of the actin cytoskeleton, riboflavin metabolism, steroid biosynthesis, and glycerophospholipid metabolism. The top 2 clusters obtained by protein-protein interaction analysis were important for the growth and development of chickens. Finally, the metabolomic analysis found key differentially accumulated metabolites (DAM) that might be account for the growth differences. Further integrated analysis identified key DEGs and DAMs that might be responsible for the observed growth differences. This study identified genes governing growth traits in Ningdu Yellow chickens, laying a theoretical foundation for the development of chicken breeding, the utilization of hybrid supporting lines, and promotion of the Chinese chicken industry.

A jasmonate-mediated regulatory network modulates diurnal floret opening time in rice.

Diurnal floret opening time (DFOT) is a pivotal trait for successful fertilization and hybrid breeding in rice. However, the molecular mechanism underlying this trait is poorly understood in rice. In this study, we combined the cytological, genetic and molecular studies to demonstrate that jasmonic acid (JA) regulates DFOT in rice through modulating the turgor and osmotic pressure of the lodicules. We show that lodicules undergo dramatic morphologic changes, accompanied by changes in water and sugar contents during the process of floret opening. Consistently, a large set of genes associated with cell osmolality and cell wall remodeling exhibits distinct expression profiles at different time points in our time-course transcriptomes of lodicules. Notably, a group of JA biosynthesis and signaling genes is continuously upregulated, accompanied by a gradual increase in JA accumulation as floret opening approaching. Furthermore, we demonstrate that the JA biosynthesis gene OsAOS1 is required for endogenous JA biosynthesis in lodicules and promoting rice DFOT. Moreover, OsMYC2, a master regulator of JA signaling, regulates rice DFOT by directly activating OsAOS1, OsSWEET4, OsPIP2;2 and OsXTH9. Collectively, our findings establish a core regulatory network mediated by JA for modulating rice DFOT and provide effective gene targets for the genetic improvement of DFOT in rice.

Comparative characterization and correlation between lipids and volatile organic compounds in NingXiang and Berkshire-Ningxiang pork

ABSTRACT Lipids and volatile organic compounds (VOCs) are essential contributors to meat flavor. However, no studies to date have comprehensively explored the lipids and VOCs in raw pork from Ningxiang (NX) pigs and their hybrid breed Berkshire × Ningxiang (BN) pigs. This study aimed to identify the lipids and VOCs and reveal the crucial lipids for characteristic flavor formation. Samples were collected from the longissimus dorsi muscle of six NX and BN 8-month-old pigs each. The intramuscular fat (IMF) content of NX pork was 5.43%, almost twice that of BN pork (p < .01). Total 187 significantly different lipids were identified between NX and BN pork (variable importance in projection scores > 1, p < .05). Further analysis suggested 38 lipids were potential markers. Out of 66 identified VOCs, 16 key VOCs were screened both in NX and BN pork. Furtherly, hexanal-D, 2-methylbutanal, 3-methylbutanal, 1-penten-3-one, 1-octen-3-ol, and ethyl acetate-D were found to be key differential VOCs. Comparing with NX pork, BN pork significantly improved pungent odor. Correlation between the lipid markers and key VOCs demonstrated that phosphatidylethanolamine (PE), phosphatidylserine (PS), phosphatidylinositol (PI), phosphatidylcholine (PC), and triglyceride (TG) were identified as key differentiating compounds for characteristic flavor. Our findings provided a novel understanding of pork identification and a basis for improving the flavor quality of NX and BN pork.

Comparison of production performance and meat quality characteristics between Guizhou Black goats and F4 generation hybrids of South African Kalahari Goats

This study spanned 6 years and 4 generations, involving the progressive crossbreeding of South African Kalahari Goat (SK) and Guizhou Black Goat (GB) over three generations, followed by cross fixation F3 with F1 in the fourth generation, accompanied by the use of molecular markers technology to select a high fertility population, resulting in the creation of a hybrid goat, BKF4 (11/16 SK lineage and 5/16 GB lineage). A comparative evaluation of the BKF4 hybrid breed and its parental breeds was conducted. Reproductive and production parameters of GB, SK, and BKF4 goat groups were monitored, including lambing rate (LR), survival rate (SR), daily weight gain at 3 months of age (DWG), and adult body weight (ABW) (n = 110, 106, 112 per group). In addition, dressing percentage (DP) (n = 12 per group) and analyses of amino acids (n = 8, 6, 10 per group) and fatty acids (n = 6 per group) were conducted to evaluate meat quality indicators. Results: (1) Reproductive and production performance: The index of LR reached 199%, significantly higher than GB and SK (p ≤ 0.001), with a SR of 95.0%, markedly higher than SK (p ≤ 0.001); DWG was 276.5 g, ABW reached 56.6 kg and with a dressing percentage (DP) of 54.5%, they are significantly surpassing GB (p ≤ 0.001). (2) Regarding meat quality: pH45-value and crude protein content (CP) increased, while intramuscular fat content increased compared to GB and ash content decreased. The amino acid composition was similar to GB, but the taste was more similar to SK. However, there were some negative impacts on fatty acid composition and functionality. (3) PCA analysis revealed that: BKF4 exhibited superior meat quality compared to GB and SK, influenced by two key factors contributing 83.49% and 16.51% to the explained variance, respectively. The key factors affecting meat quality include intramuscular fat (IMF), nutrient index (NI), PUFAs/MUFAs, n-6FAs, and drip loss (DL).

Molecular dissection of the parental contribution in Paeonia Itoh hybrids.

Hybrid breeding between herbaceous peonies (the maternal parent) and tree peonies (the paternal parent) results in Paeonia Itoh hybrids (Itoh peonies), a triploid species that combines advantageous traits from both parental species, thus offering great economic value. However, the exact genetic contribution of the two parents is unclear. In this study, we introduce a straightforward approach utilizing heterozygous SNPs and Sanger sequencing of targeted gene fragments to trace the original bases back to their parents in Itoh peonies. Our results indicate that in triploid Itoh peonies, only one set of genes are derived from herbaceous peonies, and two sets of genes are derived from the tree peonies. Notably, the presence of three distinct bases of heterozygous SNPs across multiple Itoh cultivars suggests that the gametes from the paternal parents carry two sets of heterozygous homologous chromosomes, which could be due to meiosis I failure during gamete formation. To validate our method's effectiveness in parentage determination, we analyzed two Itoh hybrids and their parents, confirming its practical utility. This research presents a method to reveal the parental genetic contribution in Itoh peonies, which could enhance the efficiency and precision of hybrid breeding programs of triploids in Paeonia and other plant species.

Unlocking the mystery of heterosis opens the era of intelligent rice breeding.

Heterosis refers to the phenomenon where the first filial offspring (F1) from genetically diverse parents displays advantages in growth rate, yield, and adaptability compared with its parents. The exploitation of heterosis in rice breeding has greatly increased the productivity, making a significant contribution to food security in the last half of the century. Conventional hybrid rice breeding highly relies on the breeder's experience on random crossing and comprehensive field selection. This process is time-consuming and labor-intensive. In recent years, rice hybrid breeding has encountered challenges stemming from limited germplasm resource, low breeding efficiency, and high uncertainty, which constrain the progress in yield increase, coupled with difficulties in balancing grain yield, quality, and resistance. Understanding the genetic basis of rice heterosis could lead to significant advancements in breeding concepts and methods. This will fully unleash the advantages of heterosis. In this review, we focus on the research progress of the genetic dissection of crop heterosis and briefly introduce some key advancements in modern intelligent breeding of rice hybrid.

Genetic Analysis for Popping Traits in Tropical Inbred Lines of Popcorn (Zea mays var. everta)

Aim: Combining ability studies in popcorn to identify superior parents for commercial hybrid breeding. Study Design: line x tester mating fashion. Place and Duration of Study: MRC, PJTSAU, Rajendranagar Hyderabad, between 2023-2024. Methodology: Popcorn (Zea mays var. everta) is a popular snack item both in India and other countries, the genetic base of popcorn germplasm is very narrow, and they resulted in few popcorn hybrids. In this study, a set of 44 popcorn hybrids obtained by crossing 22 inbred lines with two testers in line x tester fashion were evaluated along with parents and two standard checks i.e. Amber popcorn and BPCH-6. Results: Combining ability analysis implied significant differences among parents, crosses, parent’s v/s crosses for all the traits indicating variation in the selected lines of popcorn. For grain yield, lines PC 1, PC 116, PC 6-1, PC 12-2, PC 25, PC 201-1 and tester CML 451 were identified as good general combiners, whereas crosses, PC 1 x CML 451, PC 25-1 x CML 451, PC 71-1 x CML 451 and PC 5 x CML 286 showed high desirable sca effects for grain yield. The popping expansion trait in crosses viz., PC 22 x CML 451, PC 5 x CML 286, PC 72-2 x CML 451 displayed desirable sca effects. In addition to these hybrids PC 5 x CML 286 exhibited positive significant sca values along with high per se performance for both the traits. Conclusion: The lines which show desirable performance for yield and popping traits will be utilized in further development of popcorn hybrids.

Morphological and cytological assessments reveal pollen degradation causes pollen abortion in cotton cytoplasmic male sterility lines

BackgroundUnderstanding the mechanism of male sterility is crucial for producing hybrid seeds and developing sterile germplasm resources. However, only a few cytoplasmic male sterility (CMS) lines of cotton have been produced due to several challenges, like inadequate variation of agronomic traits, incomplete sterility, weak resilience of restorer lines, and difficulty in combining strong dominance. Therefore, the morphological and cytological identification of CMS in cotton will facilitate hybrid breeding.ResultsTwo F2 segregating populations of cotton were constructed from cytoplasmic male sterile lines (HaA and 01A, maternal) and restorer lines (HaR and 26R, paternal). Genetic analysis of these populations revealed a segregation ratio of 3:1 for fertile to sterile plants. Phenotypic analysis indicated no significant differences in traits of flower bud development between sterile and fertile plants. However, sterile plants exhibited smaller floral organs, shortened filament lengths, and anther atrophy on the flowering day in comparison with the fertile plants. When performed scanning electron microscopy (SEM), the two F2 populations revealed morphological variations in the anther epidermis. Cellular analysis showed no significant differences in pollen development before pollen maturation. Interestingly, between the pollen maturation and flowering stages, the tapetum layer of sterile plants degenerated prematurely, resulting in abnormal pollen grains and gradual pollen degradation.ConclusionThe results of this study suggest that fertility-restoring genes are controlled by a single dominant gene. Sterile plants exhibit distinctive floral morphology, which is characterized by stamen atrophy and abnormal anthers. Pollen abortion occurs between pollen maturity and flowering, indicating that premature tapetum degradation may be the primary cause of pollen abortion. Overall, our study provides a theoretical basis for utilizing CMS in hybrid breeding and in-depth investigation of the dominant configuration of cotton hybrid combinations, mechanisms of sterility, and the role of sterile and restorer genes.

Development and characterization of a novel intergeneric hybrid grouper (Cromileptes altivelis ♀ × Epinephelus lanceolatus ♂)

Distant hybridization often gives rise to offspring with hybrid vigor in plants and animals, and this method has also shown great potential in aquaculture. Grouper, an economically important marine species, has witnessed rapid growth in its related industry. To cultivate a new grouper variety with accelerated growth, superior meat quality, and high economic value, we successfully obtained fertilized eggs through artificial insemination, using humpback grouper (Cromileptes altivelis) as the maternal parent and giant grouper (Epinephelus lanceolatus) as the paternal parent. The hybrid groupers were successfully hatched and reared for up to 14 months. This study conducted comprehensive comparative analyses between the hybrid offspring and the parental species, focusing on embryo development, growth rate, morphological characteristics, chromosome karyotype and muscle nutrient composition. The hybrid grouper embryos completed their entire development, from fertilization to hatching, in an average duration of 20 h and 37 min, under controlled conditions of 28.5 ± 0.5 °C temperature and 28 part per thousand (ppt) salinity. Remarkably, the hybrid groupers exhibited significantly faster growth than humpback groupers, with an absolute weight growth rate 1.6 times higher. Additionally, the hybrid groupers displayed a 4.7% increase in meat yield compared to giant groupers. In terms of morphology, cluster analysis and principal component analysis were used to analyze the morphological framework data of the three grouper species, revealing that the hybrid groupers were more similar to giant groupers in their morphological framework. Chromosome karyotype and simple sequence repeats (SSR) analysis confirmed that the hybrid groupers have a total of 48 chromosomes, inheriting one set of chromosomes from each parent. This study provides a foundation for grouper hybrid breeding, and the hybrid groupers obtained in this research have the potential to become excellent commercial varieties.

Genetic comparison among some cultivars of Catharanthus roseus (L.) G. Don. using three intergenic spacers of the chloroplast genome

Abstract. Susanto AH, Dwiati M. 2024. Genetic comparison among some cultivars of Catharanthus roseus (L.) G. Don. using three intergenic spacers of the chloroplast genome. Biodiversitas 25: 2999-3007. Catharanthus roseus (L.) G. Don belongs to the Apocynaceae family and is recognized as both an ornamental plant and a medicinal herb. By means of both hybridization and mutation breeding, numerous cultivars of C. roseus have been developed over time. This encourages the necessity for molecular characterization to establish a DNA barcode for each cultivar, particularly in relation to its potential as a medicinal herb. Therefore, this study aimed to genetically compare some cultivars of C. roseus based on three Intergenic Spacers (IGS) of the chloroplast genome, namely trnQ-rps16, rps16-trnK, and trnL-rpl32. Ten samples of C. roseus were randomly collected from around Purwokerto City, Central Java, Indonesia, representing cultivars with various corolla and flower eye colors. Universal primers were used to amplify the three molecular markers. The results showed that some insertion-deletions (indels) with rps16-trnK and trnL-rpl32 were observed, indicating some potential barcodes for C. roseus cultivars, following pharmacological analysis. On the other hand, very little genetic difference among samples was found with trnQ-rps16. It can be concluded that some other molecular markers, specifically those more closely related to the expression of flower color in C. roseus, should be explored to obtain candidate DNA barcodes in assisting the authentication of medicinal herbs.

GA-GBLUP: leveraging the genetic algorithm to improve the predictability of genomic selection.

Genomic selection (GS) has emerged as an effective technology to accelerate crop hybrid breeding by enabling early selection prior to phenotype collection. Genomic best linear unbiased prediction (GBLUP) is a robust method that has been routinely used in GS breeding programs. However, GBLUP assumes that markers contribute equally to the total genetic variance, which may not be the case. In this study, we developed a novel GS method called GA-GBLUP that leverages the genetic algorithm (GA) to select markers related to the target trait. We defined four fitness functions for optimization, including AIC, BIC, R2, and HAT, to improve the predictability and bin adjacent markers based on the principle of linkage disequilibrium to reduce model dimension. The results demonstrate that the GA-GBLUP model, equipped with R2 and HAT fitness function, produces much higher predictability than GBLUP for most traits in rice and maize datasets, particularly for traits with low heritability. Moreover, we have developed a user-friendly R package, GAGBLUP, for GS, and the package is freely available on CRAN (https://CRAN.R-project.org/package=GAGBLUP).

Sources and donors of the multi-row ear trait for hybrid breeding of corn in the VIR collection

BACKGROUND: The sign of the number of rows of grains on the cob is one of the key to improving the productivity of corn. The effects of the genes that control this trait have been poorly studied. The search for sources and donors of this trait is relevant for hybrid breeding. AIM: The aim of this study is to search for sources and donors of the multi-row ear trait in the VIR collection for involvement in the breeding of hybrid corn. MATERIALS AND METHODS: The studies were carried out on 16 lines (S3–6) with different inbredness and varying the number of rows of grains on an ear from 18 to 36, the exotic 8-row race CUZCO characterized by large grains and the MP-20 population with 20–36 rows of ears. Hybridization and crop recording were carried out in the field conditions of the foothill zone of the Kabardino-Balkarian Republic. RESULTS: Based on similar phenotypic characteristics, 16 lines of corn with a multi-row cob were ranked into 5 groups. Analysis of the structure of the ear of the experimental F1 hybrid between the MP-20 population and the 8-row, large-grain race CUZCO showed that the trait of multi-row ear and large-grain is manifested as incomplete dominance. The yield potential of the experimental simple hybrid was no less than 12.2 tons per 1 hectare with a harvest grain moisture content of 37% and an FAO ripeness group of at least 600. A significant drawback of corn lines with multi-row cobs is the high harvest moisture content of the grain. CONCLUSIONS: The collection of multirow maize lines serves as a valuable source of genes that control important quantitative traits and can be involved in the breeding of hybrid maize for its improvement.

Screening of New Dendrobium officinale Strains Adapted to Karst Forest Environmental Stress Based on Electrophysiological Detection Method

At present, the main methods of breeding Dendrobium officinale (D. officinale) include introduction and domestication, selective breeding, hybrid breeding, and mutation breeding. In the process, traditional methods of field investigation of agronomic traits are often used to select resistant varieties. Although these breeding methods are effective, they have a certain degree of subjectivity and empiricism, and the breeding cycle is long. Electrophysiological instruments were used in this experiment to test the material transport and metabolic capacity of D. officinale in a karst forest epiphytic environment and to quickly evaluate the suitability of different strains of D. officinale in a drought environment. These instruments detected the data on electrophysiological information of leaves of different strains of D. officinale under long-term drought conditions, providing immediate access to the inherent electrophysiological information of the leaves of these strains. Based on the electrophysiological parameters of D. officinale leaves as defined by the inherent electrophysiological information of plants, the water metabolism, nutrient transport, and metabolic capacity in different leaves were evaluated. The key electrophysiological indexes were verified by combining the results of chlorophyll fluorescence and chlorophyll content. The results indicate the following: (1) Parameters defined based on electrophysiological information effectively characterized the differences in intracellular water utilization, the nutrient transport status, and the metabolic capacity of different D. officinale strains. (2) The intrinsic physiological resistance, intrinsic physiological reactance, active nutrient transport capacity, and passive nutrient transport capacity were closely related to the growth status and chlorophyll function of D. officinale leaves. These electrophysiological parameters could serve as critical indicators for evaluating the drought resistance of D. officinale. (3) Under severe drought stress, strain LH1 exhibited less leaf damage, adequate water/nutrient supply, vigorous life activities, and excellent drought resistance. We found that strain LH1 demonstrates better adaptation to the arid environment of karst forest lands. The electrophysiological detection method employed in this study offers a new technique for screening wild-cultivated D. officinale resistance strains. The results indicate that the real-time online leaf electrophysiological information measured by the method in this study can characterize the energy and material metabolism of crops, greatly improving the efficiency of crop-variety selection and reducing costs. These conclusions can be used to obtain real-time information on the transmission of water and nutrients within plant cells and can provide theoretical support for studying the adaptation mechanisms of crops to adverse environments.

Validation of the Residual Feed Intake Model in Brangus Heifers: Determination of the Optimal Days on Feed Interval to Estimate Dry Matter Intake and Average Daily Gain.

Brangus cattle are gaining popularity in the Southeast U.S. due to the desirable heat tolerance from their Brahman influence combined with the superior carcass merit aspects of Angus genetics. However, little is known about the optimal evaluation conditions for this hybrid breed when placed on test for Residual Feed Intake (RFI), a heritable measure of feed efficiency that allows improvement in performance without altering carcass traits. To address this, dry matter intake (DMI) was measured on Brangus heifers for 70-d to determine the optimal days on feed required to estimate feed intake and ADG and assess if inclusion of ultrasound measures of carcass merit into the model impact RFI rankings for this breed. The 56-d test period had a regression coefficient of 0.96 (p < 0.0001), R2 = 0.94, rp = 0.97 (p < 0.0001), and rs = 0.97 (p < 0.0001), indicating little change in rank of cattle for DMI compared to a 70-d test. ADG was the limiting factor in determining test duration. Based upon examining only heifers that calved, ultrasound backfat measures should be included in the RFI model to normalize for differences in heifer maturity. Results from this study indicate that a test duration of 56-d is sufficient to accurately estimate DMI in this population. This data indicates on-test duration can be shortened, enhancing the rate of genetic change by reducing cost and increasing the number of animals that can be tested annually.

Assessment of the genetic diversity and population structure in Moringa oleifera accessions using DNA markers and phenotypic descriptors

Moringa (Moringa oleifera Lam.) is one of the multipurpose trees with significant promise as a high-value crop of industrial importance, having nutritional, therapeutic, and prophylactic properties. Genetic diversity is a cornerstone of any crop improvement program and plays a key role in the selection of promising parental lines for hybrid breeding. Morphological and molecular markers have been proven to be potential tools for the evaluation of genetic diversity, crop genetic improvement, and conservation of plant genetic resources. In the current study, morphological descriptors, RAPD, and SCoT markers were used to determine genetic diversity among 28 M. oleifera accessions. Significant morphological variations were noted for several economic traits across the accessions studied. Four primary clusters were visible on the dendrogram based on phenotypic markers, indicating clustering of accession from a shared geographical habitat. No correlation was estimated between morphological traits, indicating an environmental influence. Three RAPD and seven SCoT primer sets produced 37 and 46 markers, with 53.2 and 71.3% polymorphisms, respectively. Based on genotypic data and the UPGMA approach, all 28 accessions were separated into two major clusters in the phylogenetic tree, irrespective of any geographical areas. The clustering pattern indicates widespread plant species and rapid gene flow through cross-pollination in Moringa populations. Three subpopulations of the involved accessions were identified by population structure analysis; however, there was only a weak link with the location of plant cultivation. The expected heterozygosity for the three subpopulations varied from 0.23 to 0.32, as per R-based structural analysis. AMOVA's attribution of 86% and 19% of all variations to within- and between-populations, respectively, indicates that there has been gene flow across geographic regions. The PCA showed a wide distribution of genotypes in the scatterplot, also suggesting huge genetic variation among the M. oleifera population. The study revealed a significant level of genetic diversity among M. oleifera accessions, which can be harnessed to conserve plant genetic resources and develop high-yielding, nutrient-dense Moringa cultivars.

Is the CslF6 gene involved in the accumulation of (1,3;1,4)-β-D-glucan in wheats, their wild relatives and their hybrids?

Mixed linkage (1,3;1,4)-β-d-glucan (MLG) is a well-recognized bioactive carbohydrate and dietary fibre with expanding applications in food industry. The MLG are small components of the cell wall of vegetative tissues of cereals synthetized by members of the Cellulose Synthase-Like genes (Csl). Within the family, the CslF6 has been the major contributor in wheat. It is of significant health and economic benefits to enhance MLG content in wheat, a staple grain with naturally low MLG levels. This study investigated the role of CslF6 gene in MLG synthesis and analysed total MLG contents, cell wall monosaccharide, glycosidic linkage composition, and profile of major comprising oligosaccharides of MLG in various wheat genotypes, their wild relatives (Aegilops caudata and Dasypyrum villosum), and hybrids between them. We observed a relationship between CslF6 gene expression and MLG accumulation across the different wheat lines. While Aegilops caudata and Dasypyrum villosum exhibited higher MLG content than other genotypes, hybrid breeding led to an increase in MLG content by 24.4% in durum wheat and 43.3% in T. aestivum. Variations in the ratios of major oligosaccharides released from MLG by lichenase treatment and in the compositions of cell wall monosaccharides and glycosidic linkages were also found. This study demonstrates that HPAEC-PAD and GC–MS-based glycomics are invaluable tools to assist breeders in selecting high MLG lines.

Assessment Results of Salinity Stressed F2 Population Originated from Interspecific Hybridization of Eggplant with Wild Relative Solanum incanum L.

Salinity, which is one of the major abiotic stresses, prevails in mostly arid and semiarid areas that is nearly 20% of the world’s cultivated area. Excessive amounts of salt around the plant root zone are detrimental to vegetative growth and economic yield. Today salinization is still severely expanding and posing a great threat to the development of sustainable agriculture. Although eggplant (Solanum melongena L.) is considered moderately sensitive, soil salinity mitigates strictly the growth and yield. Eggplant has significant crop wild relatives (CWRs) which are thought to be more tolerant to abiotic stresses and it is substantial to exploit their potential against salinity in hybrid breeding studies. It has previously been proven that Solanum incanum L. has tolerance to salinity stress. This study aimed to improve salinity-tolerant pure eggplant lines. Therefore, the acquired F2 population from interspecific hybridization between the pure line (BATEM-TDC47) with distinctive features from BATEM eggplant gene pool and S. incanum L., were subjected to salinity stress at 150 mM NaCl level with its parents and F1 plants. On the 12th day after the last salt treatment, the plants were evaluated using a 0-5 visual scale. Among the 256 stressed plants, 50 F2 individuals were determined to be salt tolerant. Additionally, some of their morphological and physiological features, such as shoot length, stem diameter, number of leaves, anthocyanin presence, prickliness, malondialdehyde (MDA), and proline levels, were studied and compared to the controls of their parent and F1 plants. Results showed that shoot length and stem diameter decreased dramatically under salt stress. According to the analysis, the average MDA and proline levels of the F2 population were identified as 10.9 µ mol g-1 FW and 8.4 µ mol g-1 FW, respectively. The distinguished 50 F2 plants that showed salinity tolerance were transferred to the greenhouse and self-pollinated to produce the F3 generation.