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The climate is continuously changing, consequently increasing the drought-affected areas. As such, it challenges breeders to develop adaptive and drought-tolerant sunflower (Helianthus annuus L.) cultivars through evaluation and inducing genes tolerant to drought. Hence, the recent study aimed to assess the sunflower hybrids during 2019-2020 under well-watered and stressed conditions in a splitplot design with four replications at the Sindh Agriculture University, Tandojam, Pakistan. The observed data determined heterotic effects among 15 F1 hybrids for days to 75% flowering, days to 75% maturity, stem diameter, head diameter, biological yield plant-1, seeds head-1, seed index, and seed yield plant-1. The mean squares due to genotypes, treatments, and genotype by treatment were significant for all the traits, which exhibited that genotypes performed significantly across the environments for the above-cited traits. The F1 hybrids, such as, Mehran x Pehawar-93, gave maximum negative heterotic effects for phonological traits which will benefit the development of short-duration sunflower hybrids. Further, F1 hybrids like Thatta x UC-666 displayed higher heterotic effects for head diameter, stem diameter, number of seeds plant-1, seed index, and biological plant-1 and PSF-025 x B2 and HO.1 x B2 gave higher heterotic effects for the number of seeds head-1 and seed yield plant-1 under stress environment. [ABSTRACT FROM AUTHOR]

For the sustainable improvement of sorghum (Sorghum bicolor L.), local genotypes were conventionally crossed in East Java, Indonesia to determine a) the crossing success of different genotypes, b) germination percentage and seed setting traits, and c) the combining ability and heterotic effect of sorghum parental genotypes and their F1 diallel hybrids. Three sorghum genotypes (‘Lamongan-1’, ‘Tulungagung-2’, and ‘Jombang’) from the local germplasm were collected from various regions in East Java, Indonesia, and were crossed in a complete diallel design. The experiment was carried out in a randomized complete block design with four replications during 2018–2019 at the Agrotechnology Laboratory, Faculty of Agriculture, University of Muhammadiyah, Malang, Indonesia. Results showed that the parental genotypes and their F1 hybrids exhibited significant differences in seed weight and seed diameter and nonsignificant differences in germination percentage and seed setting. The parental genotype ‘Tulungagung-2’ and its hybrids ‘Jombang’ × ‘Tulungagung-2’, ‘Tulungagung-2’ × ‘Lamongan-1’, and ‘Jombang’ × ‘Tulungagung-2’ presented the highest germination percentages, seed setting, seed weights, and seed diameters. The genotype ‘Tulungagung-2’ had the highest general combining ability and was identified as a good general paternal and maternal parent for the production of promising F1 hybrids. The hybrid ‘Jombang’ × ‘Lamongan-1’ had the highest specific combining ability for all of the characters and was recognized as a promising F1 hybrid for improving sorghum yield. Cluster analysis divided all of the parental genotypes and their F1 hybrids into two large groups with a similarity of 13.13%. [ABSTRACT FROM AUTHOR]

Seven lines (‘VH-292’, ‘VH-259’, ‘Bt-802’, ‘Sadori’, ‘Shahbaz’, ‘CRIS-342’, and ‘Bt.ZZ.NL-370’), and three testers (‘VH-291’, ‘FH-113’, and ‘IR-3701’) of upland cotton (Gossypium hirsutum L.) were crossed through line-by-tester mating to produce 21 F1 hybrids. The lines, testers, and their F1 and F2 populations were grown in a randomized complete block design with three replications at Sindh Agriculture University, Tandojam, Pakistan, in consecutive cropping seasons. Analysis of variance revealed that the genotypes (including parental lines, testers, and their 21 F1 and F2 populations) and parent vs. hybrids differed significantly for all the studied traits, except for plant height in the F2 population and sympodial branches plant−1 in the F1 and F2 populations. Lines ‘VH-292’ and ‘VH-259’ and testers ‘VH-291’ and ‘FH-113’ exhibited higher plant height, sympodial branches, bolls plant−1, and boll weight than other genotypes and were identified as suitable parental genotypes for hybridization. The F1 and F2 populations of ‘VH-292’ × ‘VH-291’ and ‘VH-292’ × ‘FH-113’ produced more sympodial branches, bolls plant−1, and seed cotton yield plant−1 than other crosses. The F1 hybrid of ‘Bt-802’ × ‘VH-291’ and the F2 population of the ‘Sadori’ × ‘VH-291’ cross produced higher boll weight than other genotypes. Overall, the mean performance of the F1 hybrids for all the traits was better than that of their parents and the F2 populations likely due to heterotic effects in the F1 populations and inbreeding depression in the F2 populations. The significant mean squares for parental genotypes, crosses, and parents vs. crosses indicated that the data obtained in this work are valuable for determining parental performance, hybrid evaluation, heterotic effects, and inbreeding depression. Significant mean squares due to parents vs. crosses revealed the good scope of heterotic effects in the F1 populations for all the traits. [ABSTRACT FROM AUTHOR]

Heterosis breeding is a potential technique to improve yields in sesame. Twenty-four diverse sesame genotypes were used as male parents and highly adoptable 3 local varieties were used as female parents. Thirty-eight hybrids were produced during rabi, 2013 and were evaluated along with parents and 3 checks during summer, 2014 in Randomized Block Design at Regional Agricultural Research Station, Polasa, Jagtial, India. The data was recorded for 8 biometrical traits viz., days to 50% flowering, days to maturity, plant height, number of primary branches per plant, number of capsules per plant, capsule length and number of seeds per capsule, 1000-seed weight and seed yield per plant. In this study, highly significant differences were recorded among sesame hybrids for all the traits studied. Further, 2 hybrids Swethathil x VS 07-023 and Swethathil x JL SEL 05-3 had recorded highest standard heterosis of 13.40% and 10.70% respectively. The same hybrids recorded statistically significant superior seed yield per plant ie., 28.7 g and 28.0 g respectively. These potential crosses can be utilized for further breeding program to develop potential purelines. [ABSTRACT FROM AUTHOR]

A 5 x 5 half diallel analysis was carried out involving 5 diverse genotypes of dolichos bean comprising pole and bush type growth habits to characterize the gene action involved in the inheritance of some of the quantitative traits and to identify good general-and specific-combiners. The results indicated additive genetic effects for number of inflorescences per plant, number of nodes per inflorescence, number of flower buds per inflorescence and protein content of pod was evident. In contrast, length of inflorescence, number of pods per inflorescence, pod length and number of seeds per pod were influenced by non-additive gene effects, while the characters like days to first flowering, days to 50% flowering, number of pods per plant, pod width, pod weight, shelling percentage of fresh pod and pod yield per plant were controlled by both additive and non-additive gene effects. Three parents namely, BCDB 1, DOLP VAR 10 and DOLP VAR 5 and 4 cross combinations i.e., DOLP VAR 10 x DOLB VAR 2, DOLP VAR 10 x Arka Jay, BCDB 1 x DOLB VAR 2 and DOLP VAR 5 x Arka Jay were identified as good general-and specific-combiners which could be exploited in future breeding programme. As high as 20.0% heterobeltiosis for pod yield per plant has been recorded through pod weight in this crop. [ABSTRACT FROM AUTHOR]

The magnitude of heterosis over mid-parent and better-parent for yield and yield contributing characters were calculated in 7 x 7 diallel set of four winter (Druchamp, Fanjai 2, Wei 132 and Zhong 65) and three spring wheat (HD 2687, UP 2425 and PBW 373) for two years. For grain yield 19 crosses showed heterobeltiosis as well as mid-parent heterosis in both the years. HD 2687 among spring and Zhong65 among winter adjudged best parents on the basis of high heterotic values for grain yield and its attributes. Winter x spring and winter x winter wheat crosses were found to be the potential crosses for high heterosis for grain yield per plant. On the contrary spring x spring and spring x winter were found to be the potential crosses for high heterosis for biological weight per plant. On the basis of high heterosis and stable performance Zhong 65/ HD 2687 and Zhong 65/ UP 2425 were the best winter x spring crosses followed by Druchamp/ Wei 132 a winter x winter cross. Heterosis for biological yield per plant, thousand grain weight, grain weight per ear, effective tillers per plant were independently associated with grain yield per plant in spring x winter as well as in winter x spring wheat crosses, therefore, heterosis for yield was through component heterosis in these crosses. The present study suggests ample scope for exploitation of heterosis for commercial production of hybrid wheat by involving winter wheat gene pool for getting further break through in wheat yields. [ABSTRACT FROM AUTHOR]

In cotton (Gossypium hirsutum L.), 45 cross F1 hybrids were produced by using 10 x 10 half-diallel fashion and were evaluated along with their 45 F2s and 10 parents in randomized complete block design replicated thrice during 2002. The magnitude of heterosis over mid-parent and better parent, as well as inbreeding depression, was calculated for various quantitative traits. Twenty seven F1 crosses showed significant positive heterobeltiosis for seed cotton yield. The cross F 1861 x RS 2115 showed highest heterobeltiosis for seed cotton yield and number of bolls plant-1 whereas LH 1836 x Pusa-101 and LH 1861 x H 1123 showed lowest heterobeltiosis for seed cotton yield and bolls plant-1, respectively. Therefore, eight crosses (F 1861 x C-2602-WIR-6109, C-2602-WIR-6109 x LH 1896, C-2602-WIR-6109 x Pusa-101, PIL 8-5 x LH 1896, PIL 8-5 x H 1123, LH 1836 x H 1123, LH 1861 x LH 1896 and H 1123 x RS 2115) were considered most promising for seed cotton yield per plant and other important characters. Significant negative inbreeding depression was recorded for yield and yield contributing traits indicating that the F2 was superior to the F1. The study showed the potential of commercial exploitation of heterosis through the production of hybrid cotton, as well as the potential of isolating the pure lines among the progenies of heterotic F1s for improvement of yield potential in upland cotton. [ABSTRACT FROM AUTHOR]