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This study was conducted to evaluate the combining ability of newly acquired maize inbred lines over the environments. Twenty-eight crosses developed by crossing eight elite inbreds in a half-diallel mating design were evaluated during kharif, 2019 for 12 agro-morphological traits in RBD with two replications at two different environments reflecting diverse agro-climatic and ecological conditions of North-Western Himalayas (SAREC, Kangra and HAREC, Bajaura). Analysis of variance showed that there was sufficient amount of genetic variability in the material studied. In accordance to Bartlett’s test, error variance was homogeneous only for six traits. Estimates of σ2SCA were higher as compared to σ2GCA both within and across environments for all the traits, except days to 75 per cent brown husk at Kangra, representing prevalence of non-additive gene action for these traits. The inbred line B73 at Bajaura, and LM14 at Kangra were found to be good general combiner for most traits. The inbreds with good GCA can be used as potential parents for the development of high yielding single cross maize hybrids. The hybrid combinations namely, B73 × BAJIM1811 and BAJIM1522 × BAJIM1811 were identified as potentially superior ones at Kangra and Bajaura environments. The identified promising hybrids need further assessment for their superiority in performance across the locations and over years.

The current breeding effort aims to develop new wheat genotypes with higher genetic potential, thereby contributing to food security. Ten wheat genotypes were crossed in a half-diallel mating design. The F1 progeny from the 45 crosses, along with their ten parents, were evaluated in a randomized block design to estimate combining ability and the nature of gene action. Analysis of variance for combining ability revealed significant mean squares for both general and specific combining abilities across all studied traits. This indicates the importance of both additive and non-additive gene effects in the inheritance of these traits. The GCA/SCA ratio suggested the predominance of non-additive genetic action for all studied traits. Only five parents (HD3086, UP 2748, WH 1105, UP 2565, and HD 2967) exhibited good general combining ability for yield and associated traits. However, but none of them were found good combiners for all traits. Twenty-one crosses exhibited significant specific combining ability for yield and associated traits. The crosses UP 2748 x HD 3059, UP2565 x HD3086, WH 1105 x UP 2526, WH 1105 x WH 1021, and HD 2967 x WH 1021 were identified as good specific combiners for higher grain yield and associated traits. Utilizing these crosses in breeding programs that exploit heterosis can lead to the creation of new wheat genotypes with a broader genetic base. This approach, which involves crossing high-performing parents for some traits with low-performing parents for others, has the potential to produce offspring with superior characteristics in the next generation due to interactions between dominant genes.

Geraniums (Pelargonium spp.) are ornamental plants that are widely popular because of their abundant flowering, color variability, different flower patterns, and ease of cultivation. Genetic breeding of this species aims to reduce the plant size and flower color. The objective of this study was to carry out morphoagronomic characterization of parents and F1 hybrids and to estimate the combined capacity and hybrid performance in the circulating diallel in F2 geranium (Pelargonium sp.). We obtained 18 and 275 plants from the F1 and F2 generations, respectively. Characterization of the parental genotypes and F1 and F2 hybrids was performed based on the descriptors for Pelargonium. Parents and F1 hybrids were grouped using the Tocher and UPGMA methods and diallel analyses in the F2 generation. The F1 hybrids G8, G11, and G17 exhibited color combinations suitable for commercialization and are promising for inclusion in breeding programs. The effects of general combining ability (GCA) and specific combining ability (SCA) were significant for these traits were also significant. The results showed the presence of both additive and non-additive genes. However, non-additive and dominant genes were predominant in most characteristics studied. Diallel analysis of the F2 hybrids revealed that the best hybrid combinations for reducing plant height were 14 × 11, 14 × 13, and 15 × 12. Therefore, the implementation and use of diallel analysis were efficient in selecting superior parental genotypes and producing hybrids with high yields. [ABSTRACT FROM AUTHOR]

Combining ability assessment helps select parents and hybrids with high performance, which can lead to increased yield and effective crop improvement. The present study aimed to evaluate 24 diverse crosses for ten different quantitative traits using line x tester mating in the kharif season. The experiment involved the assessment of crosses, which included 4 females, 6 males, and 1 commercial cultivar (Nishant). The evaluation employed a randomized block design (RBD) with three replications. Major discrepancies were observed in the genotypes of both parents and hybrids for all traits, indicating a significant amount of variation in fruit yield and other characteristics that contribute to yield. JBR-20-05 was found the best general combiner for days to 50% flowering, fruit length and plant height. JBR-20-04 was found to be the best general combiner for average fruit weight, fruit girth and total fruit yield per plant. The genotype identified in the JBR-20-07 study, resistant to fruit and shoot borer infestation, held significant potential for use in breeding and selection programs to enhance the resistance of brinjal varieties. Estimation of Specific combining ability effect revealed that among the hybrids, the hybrids JBR-20-04 x JBR-20-05 recorded highly significant specific combining ability (SCA) effects for total fruit yield per plant. The cross JBR-20-03 x JBR-20-05 showed high desirable significance to SCA for fruit and shoot borer infestation. Variance due to general combining ability was less than the variance due to SCA, and the ratio of GCA to SCA variance was less than unity. When choosing hybrids to enhance yield in brinjal (Solanum melongena L.) through breeding, it is crucial to prioritize specific traits that directly contribute to increased production. [ABSTRACT FROM AUTHOR]

The most important step in plant breeding is the correct selection of parents, and it would be wise to use heterotic groups for this. The purpose of this study is to analyse yield and its components as well as genetic diversity in line × tester wheat populations. It also seeks to present a coherent framework for the isolation of early superior families and the development of heterotic groups in bread wheat. F1 and F2 generations of 51 genotypes, including 36 combinations between 12 lines and three testers and 15 parents, were evaluated for yield and its components in a three-replication experiment according to the randomized block design. Line × tester analysis of variance, general and specific combining abilities, heterosis, heterobeltiosis and inbreeding depression were calculated. Heterotic groups created based on general and specific combining abilities were compared with each other. The results showed that there was sufficient genetic variation in the population and that further genetic calculations could be made. The selections made based on general and specific combining abilities, heterosis values and average performance of genotypes without heterotic grouping indicated different genotypes for each feature. The creation of heterotic groups made it possible to select genotypes that were superior in terms of all the criteria listed. It was concluded that heterotic groups created based on specific combining abilities may be more useful for breeding studies.

In this article we compared two approaches: one is Griffing approach for numerical components and other is Hyman's approach for graphical representation of the components through the mating design of Complete Diallel Cross design for p=5 parental lines. Griffing (1956) approach was a numerical approach based on the estimates of combining ability effects. Here use his fourth method. Hayman (1954) approach also have four components namely (i) complete, (ii) partial, (iii) over-dominance and (iv) no dominance. Hayman's approach based on the estimation of parts of variation. We use three mutually orthogonal Latin squares design of order 5 for the construction of mating designs. ANOVA and estimates of combining ability derived and analyzed. We demonstrate the numerical accuracy of the proposed design Griffing method I and Hayman's method by using Turnip data of 5x5 crosses of plant height. [ABSTRACT FROM AUTHOR]

Introduction Low diversity and poor genetic basis of germplasm in temperate regions is a significant challenge in maize breeding. Maize germplasms from tropical and subtropical regions often contain a broader genetic base and show larger diversity than germplasms from temperate regions. Therefore, it seems that foreign germplasms, especially germplasms from tropical and subtropical regions, can be used as a potential solution to strengthen the genetic base of germplasm in temperate regions. However, the efficiency of screening methods to identify superior and suitable sources of foreign germplasm remains a major challenge. The objective of this study was to determine the optimum number of testers and select suitable testers for screening maize lines derived from tropical and subtropical CIMMYT germplasm. Materials and methods In this experiment, three testers of temperate regions (MO17, B73, K1264/5-1) were crossed with 25 lines originated from the CIMMYT maize germplasm based on line×tester mating system. A total of 75 crosses along with the control hybrid (SC704) were evaluated in alpha-lattice experimental design in two replications each with four incomplete blocks in two regions (Moghan and Jiroft). Analysis of variance was done based on line×tester method, as well as separation of the effect of crosses into its components using the method suggested by Kemptorn (1957). GGE-biplot graphical analysis based on the methodology proposed by Fan et al. (2010) was also used to estimate the effects of general combining ability (GCA) and specific combining ability (SCA). Research findings The results showed that out of the 75 crosses, 32 crosses had higher and significant grain yield compared to the control hybrid SC704. The superiority of the superior cross compared to the control hybrid ranged from 1.46 to 3.77 tons per hectare. These findings highlighted the potential of utilizing tropical and subtropical CIMMYT germplasm to enhance maize yield in temperate regions of Iran. Based on the results, the lines No. 22, 9, 19, 12, 20, 5, 17, 21, 24, 14, 15, 23, and 11 had the highest positive GCA for grain yield, respectively. In general, in terms of grain yield, GCA, and SCA, it is possible to directly use lines No. 4, 5, 9, 11, 12, 19, 22, and 24 extracted from tropical and subtropical CIMMYT germplasm to improve grain yield in temperate regions. Evaluating the efficiency of the temperate maize testers also showed that two testers B73 and MO17 were highly efficient in selecting superior line derived from tropical and subtropical CIMMYT germplasm. Conclusion The results of the current study showed that it is possible to use maize germplasms from tropical and subtropical regions of CYMMIT to improve grain yield in temperate regions. Also, one temperate maize tester has the ability to distinguish superior sources (not all of them), although the use of two testers greatly reduces the risk of not choosing (deleion) a superior source. [ABSTRACT FROM AUTHOR]

In the present study twenty-eight hybrid combinations resulting from the halfdiallel mating of eight quality protein maize (QPM) inbred lines were chosen in order to examine the potential to combine and gene activity for ten yield and component attributes. As part of the All India Coordinated Research Project (AICRP) on maize during the kharif-2020 season, the experiment was done at the research farm of college of Agriculture, Odisha University of Agriculture & Technology (OUAT) Bhubaneswar, using a randomized complete block design replicated thrice. Every observation recorded was subjected to statistical evaluation and it was revealed that the mean squares derived from the general combining ability (gca) and specific combining ability (sca) were highly significant (p ≥0.01). Estimates of sca effects were greater than that of gca effects for all of the variables used in the study, suggesting to the predominance of dominant gene action. The inbred lines Q4-DQL 2221-1-1(833.792), Q2-DQL 2099 (517.658) and Q3- DQL 2159 (350.325) shows high gca effects for yield and its attributing traits due to more additive gene action thus identified as good general combiners for yield. Twelve of the twenty-eight crosses showed significant (p ≥0.01 and 0.05) positive sca effect on grain yield. The best experimental crosses for grain yield based on per se performance and sca effects were Q2 x Q8 (2106.748), Q1 x Q6 (2053.048), Q3 x Q7 (2027.082), and Q3 x Q6 (1719.884). [ABSTRACT FROM AUTHOR]

In the present study twenty-eight hybrid combinations resulting from the half-diallel mating of eight quality protein maize (QPM) inbred lines were chosen in order to examine the potential to combine and gene activity for ten yield and component attributes. As part of the All India Coordinated Research Project (AICRP) on maize during the kharif-2020 season, the experiment was done at the research farm of college of Agriculture, Odisha University of Agriculture & Technology (OUAT) Bhubaneswar, using a randomized complete block design replicated thrice. Every observation recorded was subjected to statistical evaluation and it was revealed that the mean squares derived from the general combining ability (gca) and specific combining ability (sca) were highly significant (p ≥0.01). Estimates of sca effects were greater than that of gca effects for all of the variables used in the study, suggesting to the predominance of dominant gene action. The inbred lines Q4-DQL 2221-1-1(833.792), Q2-DQL 2099 (517.658) and Q3- DQL 2159 (350.325) shows high gca effects for yield and its attributing traits due to more additive gene action thus identified as good general combiners for yield. Twelve of the twenty-eight crosses showed significant (p ≥0.01 and 0.05) positive sca effect on grain yield. The best experimental crosses for grain yield based on per se performance and sca effects were Q2 x Q8 (2106.748), Q1 x Q6 (2053.048), Q3 x Q7 (2027.082), and Q3 x Q6 (1719.884).

The most important step in plant breeding is the correct selection of parents, and it would be wise to use heterotic groups for this. The purpose of this study is to analyse yield and its components as well as genetic diversity in line × tester wheat populations. It also seeks to present a coherent framework for the isolation of early superior families and the development of heterotic groups in bread wheat. F 1 and F 2 generations of 51 genotypes, including 36 combinations between 12 lines and three testers and 15 parents, were evaluated for yield and its components in a three-replication experiment according to the randomized block design. Line ×  tester analysis of variance, general and specific combining abilities, heterosis, heterobeltiosis and inbreeding depression were calculated. Heterotic groups created based on general and specific combining abilities were compared with each other. The results showed that there was sufficient genetic variation in the population and that further genetic calculations could be made. The selections made based on general and specific combining abilities, heterosis values and average performance of genotypes without heterotic grouping indicated different genotypes for each feature. The creation of heterotic groups made it possible to select genotypes that were superior in terms of all the criteria listed. It was concluded that heterotic groups created based on specific combining abilities may be more useful for breeding studies., Competing Interests: Imren Kutlu is an Academic Editor for PeerJ., (©2024 Deviren et al.)