Combining Ability and Gene Action for Yield Improvement in Kenaf (Hibiscus Cannabinus L.) Under Tropical Conditions Through Diallel Mating Design

Nine morphologically distinct kenaf genotypes were hybridized to produce 36 hybrids following a half diallel mating design. The combining ability and gene action of 15 yield and yield components were assessed in hybrids and their parents across two environments. Except for the mid diameter and plant height traits, there were highly significant differences (p ≤ 0.01) between both the analysis of variance of environments and the interaction of genotype and environment. For the inheritance of these traits, additive gene effects were considerable, and the expression of these additive genes was heavily influenced by the environment. Significant differences were found for all studied traits for GCA except top diameter, and SCA except plant height and top diameter, implying the presence of both additive and non-additive gene action for the inheritance of the concerned characters. For all features except top diameter and number of nodes, the magnitude of GCA variation was significantly higher than that of SCA variance, indicating the additive gene's predominance. The parental lines P1, P3 and P4 were determined to be outstanding general combiners for fibre yield and yield-related parameters. Considering combining ability and genetic analysis study together, the crosses P1 × P4, P1 × P9, P2 × P3, P2 × P5, P4 × P6, P4 × P7, P4 × P9, P5 × P8, and P7 × P9 were found promising for their heterotic response to higher fibre yield, stick yield, seed yield and and could be useful by adopting proper strategies for future improvement in kenaf breeding programmes.

Genetic analysis of grain yield and yield-attributing traits in navy bean (Phaseolus vulgaris L.) under drought and optimal environments

Knowledge of the genetic basis of navy bean (Phaseolus vulgaris L.) performance under drought stress (DS) is important for planning appropriate breeding and selection strategies in DS environments. Twenty-eight F2 progenies generated from an 8 x 8 half-diallel mating design were evaluated to determine combining ability effects and mode of gene action of grain yield (GYD) and yield attributing traits in navy bean under DS and non-stressed (NS) conditions. The experiments were conducted in two locations in a 6 x 6 square lattice design with two replications during the 2020 dry season. There were significant (p < 0.001; p < 0.05) positive correlations for number of pods per plant (NPPP), number of seeds per plant (NSPP) and 100-seed weight (SW) with GYD under both DS and NS. General and specific combining ability (GCA; SCA) effects were significant (p < 0.05) under both DS and NS for most traits indicating the importance of both additive and non-additive gene effects in the expression of the traits. Parents with best combining ability for most of the studied traits were G1, G7, G6 and G8 under NS, and G3, G4, G7 and G8 under DS. The most promising progenies with high values for GYD and its component traits under DS were G2 X G3, G2 X G8, G4 X G5, G4 X G8, and G6 X G8. Good general and specific combiners with high significant positive effects under DS should be used further in breeding for moisture stress tolerance.

Pumpkin (Cucurbita spp.): A Crop to Mitigate Food and Nutritional Challenges

The world’s food and agricultural programs have gradually declined into an unsustainable situation due to challenges such as increase in world population, varied agro-climatic regions, increase temperature, extreme sole-culture growing techniques, and water shortage. A considerable emphasis has been put on few staple food crops coupled with repeated dieting, food scarcity, and essential mineral deficits, frequently inducing dietary disorders. Because relying on staple crops may lead to serious food shortages in the future, we must adjust our dietary habits to include a diverse range of non-staple foods and maximize their use in order to achieve food security and reduce the nutritional gap. To assure healthy meals around the world, an authentic and reasonable strategy is presented to draw additional awareness towards variations in agricultural production techniques and dietary preferences. The EAT-Lancet declaration highlighted the importance of increasing agri-based foods to achieve sustainable health. Expanding overlooked crops with abundant genetic stocks and possibly beneficial characteristics is an approach that might meet food and nutritional security challenges. Although undervalued, pumpkin is a valuable vegetable herbaceous plant that contributes to global food and nutritional security. This crop has already been identified as a revolutionary age crop, balanced food, and more adapted to low soil and atmospheric circumstances than other major crops. This review paper focuses on the potential uses of pumpkin as an underutilized crop; diversification and development of hybrids, particularly hybridization breeding through diallel mating design; and how implementation of this “modern” technology would contribute to the breeding of the neglected pumpkin vegetable and stimulate productivity and nourish the world’s largest malnourished, deprived, and starved populations.

Driving Sustainable Popcorn Breeding for Drought Tolerance in Brazil

Drought currently affects several regions worldwide and tends to be more frequent due to climate change. It might compromise food security and the economic structure related to agribusiness. Popcorn has a crucial role in the Brazilian economy, but the cultivars that adapt to water stress, the most prejudicial abiotic stress for crop productivity, are unknown to date. This deficit of popcorn varieties adapted to heat and drought stresses will become more limiting with climate change. Given this scenario, knowing the genetic basis of agronomic traits under stress conditions is essential in promoting crop productivity and plant adaptation to abiotic stresses. Under two contrasting water conditions (WC) and different crop seasons (CS), we aimed to generate information about the combining ability of 10 popcorn progenitors and 15 hybrids through a partial diallel-mating design. The water stress was initiated at the male pre-anthesis stage. Significant genotype*crop seasons (G*CS), genotype*water condition (G*WC), and genotype*crop seasons*water condition (G*CS*WC) interactions were present. Regardless of CS and WC, non-additive effects controlled grain yield (GY), grain number per row (GN), ear length and diameter (ED), and 100-grain weight, while additive effects were present for popping expansion (PE). For each CS, regardless of WC, the cause-effect of GN (2018) and ED (2020) on GY seems to be an opportunity for indirect selection. Utilizing genetically broad-based hybrids is also a good opportunity for obtaining superior genotypes for GY and PE as it is possible to select inbred lines for both of these traits. We recommend the L76 × L61 hybrid for the Brazilian agribusiness context due to its greater productivity and dominance deviations.

Keberhasilan dan kompatibilitas penyerbukan sendiri dan silang pada hibridisasi interspesifik ciplukan (Physalis spp)

Tanaman ciplukan digunakan untuk menghasilkan buah segar, bahan baku nutraceutical, dan biofarmasi. Kapasitas genetik ciplukan dapat ditingkatkan dengan hibridisasi interspesifik. Ketidakcocokan adalah masalah yang muncul pada persilangan antarspesies. Tujuan penelitian adalah untuk mempelajari keberhasilan dan kompatibilitas penyerbukan sendiri dan penyerbukan silang hibridisasi interspesifik ciplukan. Penelitian dilaksanakan di Seed and Nursery Industry, Agro Techno Park, Universitas Brawijaya pada bulan Januari sampai Juni 2020. Penelitian menggunakan bahan 5 spesies ciplukan, yaitu Physalis P. angulata, P. peruviana, P. pruinosa, P. pubescens, dan P. ixocarpa. Pola perkawinan dialel digunakan serta pengamatan terhadap hasil penyerbukan diamati. Hasil penyerbukan silang interspesifik memiliki derajat kompatibilitas yang berbeda. Kompatibilitas penyerbukan sendiri pada setiap spesies tinggi. Penyerbukan silang interspesifik P. pubescens (PPB-68154-04) x P. angulata (PAN-69281) kompatibel. Inkompatibilitas parsial terdapat pada penyerbukan silang interspesifik P. angulata (PAN-69281) x P. ixocarpa (PIX-4418-2), P. pubescens (PPB-68154-04) x P. ixocarpa (PIX-4418-2) , P. pruinosa (PPN+3101) x P. angulata (PAN-69281), dan P. pruinosa (PPN+3101) x P. ixocarpa (PIX-4418-2). Inkompatibilitas lengkap terjadi pada penyerbukan silang P. angulata (PAN-69281) x P. pubescens (PPB-68154-04), P. angulata (PAN-69281) x P. pruinosa (PPN+3101), P. pubescens (PPB-68154-04) x P. pruinosa (PPN+3101), P. pruinosa (PPN+3101) x P. pubescens (PPB-68154-04), P. pruinosa (PPN+3101) x P. ixocarpa (PIX-4418-2), P. peruviana (PPV-45311-03) dan P. ixocarpa (PIX-4418-2). Penyerbukan sendiri dan penyerbukan silang yang kompatibel menghasilkan perbedaan pada karakteristik buah dan benih. P. pruinosa (PPN+3101), P. angulata (PAN-69281), dan P. pubescens (PPB-68154-04) menghasilkan jumlah benih yang berbeda pada penyerbukan silang interspesifik.AbstractCiplukan is used as a fresh fruit, nutraceutical raw materials, and biopharmaceuticals. Genetic capacity of ciplukan can be increased by interspecific hybridization. Incompatibility is an issue obtained during the interspecific hybridization. Research objective was to study success rate and compatibility of self-pollination and cross-pollination ciplukan interspecific hybridization. Research was conducted at Seed and Nursery Industry, Agro Techno Park, Universitas Brawijaya from January to June 2020. Physalis P. angulata, P. peruviana, P. pruinosa, P. pubescens, and P. ixocarpa were species included in this study. A diallel mating design pattern was used as well as observations of pollination. Interspecific cross pollination was found to have differing degrees of compatibility. Compatibility of self-pollination in each species is high. Interspecific cross-pollination of P. pubescens (PPB-68154-04) x P. angulata (PAN-69281) is compatible. Partial incompatibilities exist in interspecific cross-pollination of P. angulata (PAN-69281) x P. ixocarpa (PIX-4418-2), P. pubescens (PPB-68154-04) x P. ixocarpa (PIX-4418-2), P. pruinosa (PPN+3101) x P. angulata (PAN-69281), and P. pruinosa (PPN+3101) x P. ixocarpa (PIX-4418-2). Complete incompatibility occurred in cross-pollination of P. angulata (PAN-69281) x P. pubescens (PPB-68154-04), P. angulata (PAN-69281) x P. pruinosa (PPN+3101), P. pubescens (PPB-68154-04) x P. pruinosa (PPN+3101), P. pruinosa (PPN+3101) x P. pubescens (PPB-68154-04), P. pruinosa (PPN+3101) x P. ixocarpa (PIX-4418-2), P. peruviana (PPV-45311-03) and P. ixocarpa (PIX-4418-2). Compatible self-pollination and cross-pollination resulted differences in fruit and seed characteristics. P. pruinosa (PPN+3101), P. angulata (PAN-69281), and P. pubescens (PPB-68154-04) developed different numbers of seeds following interspecific cross-pollination.

Across-population genomic prediction in grapevine opens up promising prospects for breeding

Crop breeding involves two selection steps: choosing progenitors and selecting offspring within progenies. Genomic prediction, based on genome-wide marker estimation of genetic values, could facilitate these steps. However, its potential usefulness in grapevine (Vitis vinifera L.) has only been evaluated in non-breeding contexts mainly through cross-validation within a single population. We tested across-population genomic prediction in a more realistic breeding configuration, from a diversity panel to ten bi-parental crosses connected within a half-diallel mating design. Prediction quality was evaluated over 15 traits of interest (related to yield, berry composition, phenology and vigour), for both the average genetic value of each cross (cross mean) and the genetic values of individuals within each cross (individual values). Genomic prediction in these conditions was found useful: for cross mean, average per-trait predictive ability was 0.6, while per-cross predictive ability was halved on average, but reached a maximum of 0.7. Mean predictive ability for individual values within crosses was 0.26, about half the within-half-diallel value taken as a reference. For some traits and/or crosses, these across-population predictive ability values are promising for implementing genomic selection in grapevine breeding. This study also provided key insights on variables affecting predictive ability. Per-cross predictive ability was well predicted by genetic distance between parents and when this predictive ability was below 0.6, it was improved by training set optimization. For individual values, predictive ability mostly depended on trait-related variables (magnitude of the cross effect and heritability). These results will greatly help designing grapevine breeding programs assisted by genomic prediction.

Haplotype Reconstruction in Connected Tetraploid F1 Populations

In diploid species, many multiparental populations have been developed to increase genetic diversity and quantitative trait loci (QTL) mapping resolution. In these populations, haplotype reconstruction has been used as a standard practice to increase the power of QTL detection in comparison with the marker-based association analysis. However, such software tools for polyploid species are few and limited to a single biparental F1 population. In this paper, a statistical framework for haplotype reconstruction has been developed and implemented in the software PolyOrigin for connected tetraploid F1 populations with shared parents, regardless of the number of parents or mating design. Given a genetic or physical map of markers, PolyOrigin first phases parental genotypes, then refines the input marker map, and finally reconstructs offspring haplotypes. PolyOrigin can utilize single nucleotide polymorphism (SNP) data coming from arrays or from sequence-based genotyping; in the latter case, bi-allelic read counts can be used (and are preferred) as input data to minimize the influence of genotype calling errors at low depth. With extensive simulation we show that PolyOrigin is robust to the errors in the input genotypic data and marker map. It works well for various population designs with ≥ offspring per parent and for sequences with read depth as low as 10x. PolyOrigin was further evaluated using an autotetraploid potato dataset with a 3 × 3 half-diallel mating design. In conclusion, PolyOrigin opens up exciting new possibilities for haplotype analysis in tetraploid breeding populations.

Genetic variability, heritability and genetic advance in Triticum aestivum

The present investigation was carried out to study gene action, heterosis, correlations, variance, genetic advance, heritability using diallel mating design at Research farm, Department of Agriculture, Mata Gujri college, Fatehgarh sahib during rabi, 2016-17 and 2017-18. The experiment was carried out in Randomized Block Design and observations were recorded on fifteen characters. The best heterotic cross for grain yield per plant was Kalyan Sona × WH-1080 followed by PDW-215 × CPAN-1796, Kalyan Sona× CPAN-1796, DBW-90 × PDW-215, DBW-90 ×WH-1080 and Kalyan Sona × DBW-90. Results revealed that grains per plant showed highly significant and positive genotypic correlations with days to booting, days to heading, spike length, plant height, harvest index and peduncle length. The experimental materials for the present investigation consisted of five lines viz., Kalyan sona , WH-1080, PDW-215, DBW-90 and CPAN-1796 and one check viz., PBW-725.

Evaluation of F1 Hybrids of Bottle Gourd (Lagenaria siceraria Mol. Stand) for Yield Attributes

An investigation was carried out to study the performance of 28 hybrids of bottle gourd (Lagenaria siceraria mol. stand) through diallel mating design excluding reciprocals. Observations were recorded on the traits, viz., number of primary branches per vine, days to 50% flowering, node number at which first female flower appears, days to initiation of first female flower, number of fruits per vine, days to first fruit harvest, fruit weight, fruit size, hundred seed weight, flesh thickness, vine length and fruit yield per vine besides quality traits such as moisture content and TSS content in the fruit. Among the 28 hybrids of bottle gourd studied, thecross ‘PSPL X Pusa Naveen excelled in yield per vine, followed by the crosses ‘DBG-5XPusa Naveen. Thus, first generation hybrids can be well-utilized for exploiting hybrid vigour to achieve improved quality.