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Abstract Heterosis, recognized for improving crop performance, especially in the first filial (F1) generation, remains an area of significant study in the tobacco industry. The low utilization of leaf veins in tobacco contributes to economic inefficiency and resource waste. Despite the positive impacts of heterosis on crop genetics, investigations into leaf-vein ratio heterosis in tobacco have been lacking. Understanding the mechanisms underlying negative heterosis in leaf vein ratio at the molecular level is crucial for advancing low vein ratio leaf breeding research. This study involved 12 hybrid combinations and their parental lines to explore heterosis associated with leaf vein ratios. The hybrids displayed diverse patterns of positive or negative leaf vein ratio heterosis across different developmental stages. Notably, the F1 hybrid (G70 × Qinggeng) consistently exhibited substantial negative heterosis, reaching a maximum of -19.79% 80 days after transplanting. A comparative transcriptome analysis revealed that a significant proportion of differentially expressed genes (DEGs), approximately 39.04% and 23.73%, exhibited dominant and over-dominant expression patterns, respectively. These findings highlight the critical role of non-additive gene expression, particularly the dominance pattern, in governing leaf vein ratio heterosis. The non-additive genes, largely associated with various GO terms such as response to abiotic stimuli, galactose metabolic process, plant-type cell wall organization, auxin-activated signaling pathway, hydrolase activity, and UDP-glycosyltransferase activity, were identified. Furthermore, KEGG enrichment analysis unveiled their involvement in phenylpropanoid biosynthesis, galactose metabolism, plant hormone signal transduction, glutathione metabolism, MAPK signaling pathway, starch, and sucrose metabolism. Among the non-additive genes, we identified some genes related to leaf development, leaf size, leaf senescence, and cell wall extensibility that showed significantly lower expression in F1 than in its parents. These results indicate that the non-additive expression of genes plays a key role in the heterosis of the leaf vein ratio in tobacco. This study marks the first exploration into the molecular mechanisms governing leaf vein ratio heterosis at the transcriptome level. These findings significantly contribute to understanding leaf vein ratios in tobacco breeding strategies.

Hybridization is a widely used breeding technique in fish species that enhances desirable traits in cultured species through heterosis. However, the mechanism by which hybrids alter gene expression to form heterosis remains unclear. In this study, a group of hybrid tilapia was used to elucidate heterosis through interspecies crossing. Specifically, p38 was analyzed to describe the regulation of gene expression variation in hybrid tilapia. Transcripts from the Nile tilapia allele were found to be significantly higher than those from the blue tilapia allele in hybrid individuals, indicating that the expression of p38 was dominated by Nile tilapia sub-genomic alleles. The study also found a compensatory interaction of cis- and trans-acting elements of the Nile tilapia and blue tilapia sub-genomes, inducing a non-additive expression of p38 in hybrids. Eight specific SNPs were identified in the p38 promoter regions of Nile tilapia and blue tilapia, and were found to be promoter differences leading to differences in gene expression efficiencies between parental alleles using a dual-luciferase reporter system. This study provides insights into the non-additive expression patterns of key functional genes in fish hybrids related to growth and immunity response.

This research was undertaken to assess genetic control and combining effects of some essential traits of yield under drought stress. Forty-two hybrids under water-stressed and well-watered conditions were tested in field experiments for two years. Evaluation of the various genetic components of variation was performed. Both the additive (D) and the dominant (H1) variance components were important in most of the traits suggesting both additive and non-additive gene effects under both conditions. The study showed that the minimum number of genes under water-stressed (WS) conditions ranged from 0.02 for pod length to 16.13 for days to 50% flowering. The narrow-sense heritability ranged from 24% for the number of pods per plant and pod length to 66% for the number of days to 50% flowering under WS condition. The impacts of SCA and GCA have been determined. In both conditions IT93K-432-1 and IT97K-499-35 showed the strongest GCA results on both of the traits. Danila×IT93K-432-1, Danilla×IT97K-499-35, and TVu7778×IT99K-573-2-1 have been observed to have the best SCA effect under both conditions for most of the traits. In most traits, additive and non-additive gene effects plus additive × additive and additive × dominance gene interactions were common. In summary, additive and non-additive gene actions were detected; however, there was a preponderance of non-additive gene action in both conditions. As a result, the enhancement of these traits would involve a repetitive selection technique as a result of the prevalence of the dominant gene effect, which would allow favorable recombination of the genes in both conditions in later generations.

Genomic imprinting is an epigenetic phenomenon defined as the silencing of an allele, at least partially, at a given locus based on the sex of the transmitting parent. The objective of the present study was to detect the presence of SNP-phenotype imprinting associations for carcass weight (CW), carcass conformation (CC) and carcass fat (CF) in cattle. The data used comprised carcass data, along with imputed, high-density genotype data on 618,837 single nucleotide polymorphisms (SNPs) from 23,687 cattle; all animal genotypes were phased with respect to parent of origin. Based on the phased genotypes and a series of single-locus linear models, 24, 339, and 316 SNPs demonstrated imprinting associations with CW, CC, and CF, respectively. Regardless of the trait in question, no known imprinted gene was located within 0.5 Mb of the SNPs demonstrating imprinting associations in the present study. Since all imprinting associations detected herein were at novel loci, further investigation of these regions may be warranted. Nonetheless, knowledge of these associations might be useful for improving the accuracy of genomic evaluations for these traits, as well as mate allocations systems to exploit the effects of genomic imprinting.

Understanding the mode of inheritance of traits is vital in the selection of breeding methods for the grain yield and improvement of associated traits in a target environment. Combining ability is one of the powerful indices for the selection of the best cross combinations, parental lines that combine with other lines and the best breeding method for high grain yield improvement programmes. A total of 45 crosses were generated from ten maize varieties developed in low nitrogen environment in a diallel mating fashion without reciprocal. The resultant progenies were investigated in low- and highnitrogen soil to identify the mode of grain yield inheritance and those of related traits in the tested environments. Mean square analysis revealed the preponderance of additive and non-additive gene actions in the expression of maize grain yield and related characters tested under stress and optimal conditions. In this study, it is proved that both standard selection and hybridization breeding strategies are effective for the improvement of most traits involved. This experiment also confirmed the adequacy of sufficient variation in the gene pool present in the maize population that could be exploited in maize grain yield improvement programmes in the tropics. The ratio of SCA to GCA however emphasized the superiority of additive gene effects in the expression of most traits in the tested environments. The results, therefore, suggest that additive gene actions primarily condition the expression of maize grain yield and associated characters in the tested environments. Therefore, suggesting that the standard selection method would be effective for the improvement of most traits tested under the two environments.

Abstract Background Quantitative traits are typically considered to be under additive genetic control. Although there are indications that non-additive factors have the potential to contribute to trait variation, experimental demonstration remains scarce. Here, we investigated the genetic basis of growth in Atlantic salmon by exploiting the high level of genetic diversity and trait expression among domesticated, hybrid and wild populations. Results After rearing fish in common-garden experiments under aquaculture conditions, we performed a variance component analysis in four mapping populations totaling ~ 7000 individuals from six wild, two domesticated and three F1 wild/domesticated hybrid strains. Across the four independent datasets, genome-wide significant quantitative trait loci (QTLs) associated with weight and length were detected on a total of 18 chromosomes, reflecting the polygenic nature of growth. Significant QTLs correlated with both length and weight were detected on chromosomes 2, 6 and 9 in multiple datasets. Significantly, epistatic QTLs were detected in all datasets. Discussion The observed interactions demonstrated that the phenotypic effect of inheriting an allele deviated between half-sib families. Gene-by-gene interactions were also suggested, where the combined effect of two loci resulted in a genetic effect upon phenotypic variance, while no genetic effect was detected when the two loci were considered separately. To our knowledge, this is the first documentation of epistasis in a quantitative trait in Atlantic salmon. These novel results are of relevance for breeding programs, and for predicting the evolutionary consequences of domestication-introgression in wild populations.

The objective of the present study was to quantify the association between both pedigree and genome-based measures of global heterozygosity and carcass traits, and to identify single nucleotide polymorphisms (SNPs) exhibiting non-additive associations with these traits. The carcass traits of interest were carcass weight (CW), carcass conformation (CC) and carcass fat (CF). To define the genome-based measures of heterozygosity, and to quantify the non-additive associations between SNPs and the carcass traits, imputed, high-density genotype data, comprising of 619,158 SNPs, from 27,213 cattle were used. The correlations between the pedigree-based heterosis coefficient and the three defined genomic measures of heterozygosity ranged from 0.18 to 0.76. The associations between the different measures of heterozygosity and the carcass traits were biologically small, with positive associations for CW and CC, and negative associations for CF. Furthermore, even after accounting for the pedigree-based heterosis coefficient of an animal, part of the remaining variability in some of the carcass traits could be captured by a genomic heterozygosity measure. This signifies that the inclusion of both a heterosis coefficient based on pedigree information and a genome-based measure of heterozygosity could be beneficial to limiting bias in predicting additive genetic merit. Finally, one SNP located on Bos taurus (BTA) chromosome number 5 demonstrated a non-additive association with CW. Furthermore, 182 SNPs (180 SNPs on BTA 2 and two SNPs on BTA 21) demonstrated a non-additive association with CC, while 231 SNPs located on BTA 2, 5, 11, 13, 14, 18, 19 and 21 demonstrated a non-additive association with CF. Results demonstrate that heterozygosity both at a global level and at the level of individual loci contribute little to the variability in carcass merit.

Field pea (Pisum sativum L.) is a highly nutritious winter-season pulse crop. It is used as food, feed, and fodder and offers nutritional security to low-income people in developing countries. Different graphical approaches like Principal Component Analysis (PCA) and Genotype + Genotype × Environment (GGE) biplots were used along with the conventional line × tester to identify efficient parents, combining ability effects and distinct heterotic groups in field pea (Pisum sativum L.). The study used a line tester design (9 × 3) for seed yield and its associated traits. In the conventional analysis, lines Aman and HFP 715 and the tester GP02/1108, as well as crosses HFP 715 × GP02/1108, Aman × GP02/1108, and Pant P-243 × HFP 1426 showed the best GCA (General Combining Ability) and SCA (Specific Combining Ability) effects, respectively, for seed yield and its attributes. The σ2SCA > σ2GCA, and σ2D > σ2A in almost all the traits indicated control of non-additive gene effects. High manifestations of heterobeltiosis for seed yield were evidenced by the superiority of 24 out of 27 crosses over the better parent. The highest significant heterobeltiosis was observed in the cross HFP 715 × GP02/1108, followed by IPF 14-16 × GP02/1108, IPF 14-16 × HFP 1426, DDR-23 × HFP 1426, DDR-23 × GP02/1108, and Aman × GP02/1108 for yield and its attributes. The biplot techniques were used to analyze data and compare their results with conventional line × tester analysis. Overall, graphical analysis results were very similar to those of traditional analysis. Consequently, it can surely be assumed that these methods could be helpful in presenting data from field pea breeding experiments carried out with line × tester design.

Abstract Background Consumers purchase fresh strawberries all year long. Extending the fruiting season for new strawberry cultivars is a common breeding goal. Understanding the inheritance of repeat fruiting is key to improving breeding efficiency. Several independent research groups using multiple genotypes and analytic approaches have all identified a single genomic region in strawberry associated with repeat fruiting. Markers mapped to this region were used to evaluate breeding parents from the United States Department of Agriculture – Agricultural Research Service (USDA-ARS) strawberry breeding program at Beltsville, Maryland. Results Markers mapped to repeat fruiting identified once-fruiting genotypes but not repeat-fruiting genotypes. Eleven of twenty-three breeding parents with repeat-fruiting marker profiles were actually once fruiting, indicating at least one additional locus acting epistatically to suppress repeat fruiting. Family segregation ratios could not be predicted reliably by the combined use of parental phenotypes and marker profiles, when using a single-gene model. Expected segregation ratios were calculated for all phenotypic and marker-profile combinations possible from the mapped locus combined with a hypothetical dominant or recessive suppressor locus. Segregation ratios specific to an epistatic suppressor acting on the mapped locus were observed in four families. The segregation ratios for two families were best explained by a dominant suppressor acting on the mapped locus, and, for the other two, by a recessive suppressor. Not all of the observed ratios could be explained by one model or the other, and when multiple families with a common parent were compared, there was no predicted genotype for the common parent that would lead to all of the observed segregation ratios. Conclusions Considering all lines of evidence in this study and others, repeat-fruiting in commercial strawberry is controlled primarily by a dominant allele at a single locus, previously mapped by multiple groups. At least two additional genes, one dominant and one recessive, exist that act epistatically to suppress repeat fruiting. Environmental effects and/or incomplete penetrance likely affect phenotype through the suppressor loci, rather than the primary mapped locus. One of the dominant suppressors acts only in the first year, the year the plant is germinated from seed, and not after the plant has experienced a winter.

Thirty six entries of flax (Linum usitatissmum, L.) involving eight parental genotypes and their twenty eight hybrids were evaluated for straw yield and its related traits in the F1 during (2015/2016) and F2 populations during (2016/2017) under early (F2D1) and late (F2D2) sowing dates (two environments) in the Agricultural Research Station, Faculty of Agriculture, Ain Shams Univ., Shalakan, Kalubia Governorate. Mean squares due to genotypes, parents and crosses were highly significant for straw yield, plant height, technical stem length, fiber yield/plant, fiber percentage, fiber length and fiber fineness in the F1 and F2 generations (at early and late sowing dates), indicating that parental genotypes as well as their F1 and F2 generations exhibited reasonable degree of variability for all studied traits. Highly significant variations mean performance were found for parental genotypes and hybrids for straw yield/plant and its related traits in the F1, F2D1and F2D2, indicating presence of wide genetic variability among studied genotypes. The highest mean values were recorded under all studied environments, for straw yield/plant, fiber yield/plant and fiber fineness were found by S. 402/1 genotype, while Sakha 5 gave the highest mean values for plant height, technical stem length and fiber length. General and specific combining ability mean squares were highly significant for all studied traits in F1, F2D1 and F2D2 with the exception of a few cases, indicating the importance of both additive and non-additive gene effects in the expression of straw yield and its components. The additive effects were more important than non-additive effects under all studied environments for straw yield/plant (except at F2D2), plant height (except at F1), fiber percentage and fineness. On the other hand, the non- additive effects were more effective than additive effects for technical stem length, fiber yield/plant and fiber length. Results showed that the parents; Giza 11and Giza 12 for straw yield/plant, Sakha 5 for plant height and fiber length, Sakha 6 for fiber yield/plant, Jowhar for fiber percentage and S. 402/1, Sakha 2, Giza 12 and Sakha 5 for fiber fineness, these parents appeared to be the best general combiners for these traits. Some of the crosses exhibited highly significant and positive SCA effects included high x high and high x low general combiner parents, suggesting that the breeding procedure which utilize both additive and non-additive genetic variances would be more useful for improvement of straw yield and its components of flax.

The present investigation was carried out at Horticultural Research Station, Lam farm, Guntur, Andhra Pradesh during kharif, 2013-14 and 2014-15 to estimate the combining ability effects employing the line x tester mating design with nine lines and six testers. The analysis of variance revealed that significant differences among the parents and crosses for all the 12 characters studied. Six characters viz. fruit yield per plant, plant spread, days to 50% flowering, days to fruit maturity, number of fruits per plant and number of seeds per fruit were exhibited higher magnitude of sca variances than gca variances which revealed that non-additive gene action was played an important role in the inheritance of these trait. According to gca effects, the genotypes LCA-442, LCA-654, LCA-655, LCA-703-2 and LCA-453 found to be promising general combiners for yield and yield components. The sca effects revealed that nine crosses viz., LCA 466 x LCA 705-2, LCA 607 x LCA 703-2, LCA 355 x LCA 678, LCA 504 x LCA 705-2, LCA 446 x LCA 703-2, LCA 615 x LCA 453, LCA 442 x LCA 453, LCA 607 x G4 and LCA 654 x LCA were identified as promising hybrids for fruit yield and it’s yield component characters.

A field experiment was carried out with a view to estimate, combining ability and gene effects in brinjal (Solanum melongena L.). The experimental material comprised of 37 genotypes including 8 parents, 28 hybrids and one standard check (Surati Ravaiya) was laid out in Randomized Block Design with three replications at Regional Horticultural Research Station (R.H.R.S.), Navsari Agricultural University, Navsari, Gujarat during Rabi 2015-16. Combining ability analysis revealed that both additive as well as non-additive gene effects were important in the inheritance of all the traits studied. However, magnitude of variances due to sca was comparatively larger than those of gca for most of the economic traits indicated preponderance of non-additive gene action. Among the parents, JBGR-1, NSR-1 and JBL-08-8 were good general combiners for majority of the traits. The crosses viz., AB-09-1 × AB-12-10, AB-09-1 × AB-08-5, AB-08-5 × JBL-08-8 and GJB-3 × AB-12-10 showed higher order sca effects in addition to performance for fruit yield and its component characters.

An investigation was undertaken with a view to study the nature and magnitude of gene action for 10 quantitative traits among five crosses of brinjal through generation mean analysis. The study involved six generation viz., P1, P2, F1, F2, BC1 and BC2 of five crosses derived from six diversified parents. The results indicated that the magnitude and type of gene effects differed for the same trait in different cross combinations. Therefore, for the improvement of particular trait, segregating generations of individual crosses should be handled according to the gene action involved in its inheritance. Additive [d], dominance [h], additive x additive, dominance x dominance gene actions were equally important for primary branches per plant, fruit breadth, fruit weight, yield per plant and seeds per fruit in most of the crosses. The complimentary type of epistasis was detected for inheritance of days to first flowering and days to first fruit picking in BNDT x PPC, number of fruits per plant in PPC x BB 64, yield per plant in N-1007 x BB-64 and KASARALI x PPC, while duplicate type of epistasis was important for inheritance of remaining traits in all the crosses except in BNDT x PPC.

Because of essential economic and ecological concerns, there is increased interest worldwide in developing wheat cultivars that are more efficient in utilizing nitrogen (N) and better suited to N limitations. The objective of the present investigation was to get information on the type of gene action controlling the inheritance of wheat low-N tolerance traits in order to start a breeding program for improving such traits. Six parents of contrasting low-N tolerance were crossed in a diallel fashion. Evaluation of 6 parents, 15 F1crosses and 15 F2 crosses was done using a randomized complete block design with three replications under two levels of soil N, i.e. low-N (0 kg N/ha) and high-N (180 kg N/ha).The magnitude of dominance variance inF2's for all studied traits was much greater than that of additive variance under both high N and low N, suggesting that selection should be postponed to later segregating generations in order to eliminate masking effects of dominance variance and take advantage of the additive variance for the improvement of nitrogen use efficiency and grain yield traits. Narrow-sense heritability (h2n) in F2's was generally of higher magnitude under low-N than high-N, suggesting that it is better to practice selection for studied nitrogen efficiency and grain yield traits under low-N conditions to obtain higher values of selection gain.

The idea of synergistic interactions between drugs and chemicals has been an important issue in the biomedical world for over a century. As complex diseases, especially cancer, are being treated with various drug cocktails, understanding the interactions among these drugs is increasingly vital to ensuring successful treatment regimens. However, the idea of synergy is not limited to only the biomedical realm and these ideas have developed across many different disciplines, as well. In this review, we first discuss the various terminology surrounding the idea of synergy, providing a comprehensive list of terms defined across numerous disciplines. We then review the most common methodology for detection and quantification of synergy, including the two most prominent reference models for describing additive interactions: Loewe Additivity and Bliss Independence. We also discuss advantages and limitations to each method, with a focus on the Chou-Talalay Combination Index method. Finally, we describe how methods development and terminology have developed among disciplines outside of biomedicine and pharmacology, to synthesize the literature for readers.

This paper offers comments on a previously published paper, titled “Multiple criteria decision making (MCDM) methods in economics: an overview,” by Zavadskas and Turskis (2011). The paper's authors made great efforts to summarize MCDM methods but may have failed to consider several important new concepts and trends in the MCDM field for solving actual problems. First, the traditional model assumes the criteria are independently and hierarchically structured; however, in reality, problems are often characterized by interdependent criteria and dimensions and may even exhibit feedback-like effects. Second, relatively good solutions from the existing alternatives are replaced by aspiration levels to fit today's competitive markets. Third, the emphasis in the field has shifted from ranking and selection when determining the most preferable approaches to performance improvement of existing methods. Fourth, information fusion techniques, including the fuzzy integral method, have been developed to aggregate the performances. Finally, the original fixed resources in multi-objective programming are divided such that both decision and objective spaces are changeable. In this paper, we add new concepts and provide comments that could be thought of as an attempt to complete the original paper.

Abstrak— Tingginya jumlah kematian ibu dan anak menempatkan Indonesia di rangking teratas kawasan Asia Tenggara.Penelitian yang dilakukan untuk mengurangi jumlah angka kematian ibu dan anak yaitu penyedian sarana dalam hal ini klinik bersalin disuatu daerah, demi tercapainya Milenium Development Goals (MDGs) di tahun 2015. Pengumpulan data yang mendukung penelitian ini, yaitu melakukan konsultasi dengan kepala Dinas Kesehatan Sulawesi Selatan sehingga dihasilkan kriteria-kriteria terbaik dalam pendirian klinik bersalin. Kriteria-kriteria tersebut disusun berdasarkan studi literatur, observasi, dan wawacara.Selanjutnya kriteria tersebut diberi penilaian perbandingan berpasangan dengan AHP untuk mencari bobot prior dengan skala penilaian antara 1 – 9, sedangkan untuk mencari bobot informasional dan upper excepted value menggunakan TFN (Triangular Fuzzy Number). Hasil yang didapat dengan menggunakan Fuzzy AHP non-additive dalam pendirian klinik bersalin menunjukkan bahwa kriteria prevalensi, penduduk, kesakitan, petugas, dan sarana merupakan kriteria utama dalam pendirian klinik besalin. Metode Fuzzy AHP non-additive didalam penilaian tingkat konsistensi dilakukan pada setiap level struktur hirarki dan mampu mengakomodir ketidak konsistenan dalam penilaian. Kata Kunci— AHP(Analitycal Hierarchy Process), non-additive, TFN (Triangular Fuzzy Number), upper excepted value.

A line x tester crossing programme was done using male sterile lines and a set of 11 genetically diverse pollinators as testers. F1's along with parents were evaluated during winter and summer seasons. During the seasons, for plant height and flower size, additive gene action was higher compared to non-additive gene action, while for flowering days and stalk length, non-additive and non-additive gene actions played important role during both the seasons, indicating the usefulness of hybrids in marigold cultivation. Similarly, for flower number during winter and for plant spread during summer, both additive and non-additive gene action played significant role. For other traits, gene action was inconsistent during different seasons.