Heterosis For Yield Research Articles

Advances in Breeding for Oil Quality Enhancement in Indian Mustard (Brassica spp. L.): Achievements, Challenges, and Research Opportunities

Major objectives in oil crop improvement are enhancement of seed and oil yield, quality of oil according to its use, i.e. edible or industrial uses, breeding of varieties that fit in different cropping systems and breeding biotic and abiotic stress resistant/tolerant varieties. Despite traditional breeding approaches, including pure line breeding, yielding only modest gains in productivity, recent advancements in mustard breeding have led to significant breakthroughs in both productivity and oil quality. This review discusses the innovative breeding strategies that have contributed to these advancements, with a focus on hybrid development, oil quality enhancement, and biotechnological approaches. To enhance productivity, researchers at the University of Delhi have developed hybrid seed production techniques using transgenic Barnase-barstar systems and cytoplasmic male sterility (CMS) systems. These systems enable large-scale hybrid seed production, with field trials demonstrating significant yield heterosis ranging from 31% to 55% compared to national check varieties. In addition to productivity, improving oil and meal quality has been a key objective. By integrating genes from canola-quality mustard lines, breeders have achieved reductions in erucic acid and glucosinolates, enhancing the health profile and industrial applicability of mustard oil. A high-density linkage map developed using an F1 double haploid mapping population has facilitated the marker-assisted backcross breeding of desirable traits, enabling precise transfer of key quality traits. Transgenic approaches, such as antisense RNA technology, have led to the development of high-oleic, low-linoleic mustard lines with improved fatty acid profiles. These advancements reflect a strategic combination of conventional and biotechnological methods, demonstrating a clear pathway for boosting mustard yields while enhancing oil quality. Molecular markers reported for genetic diversity assessment, mapping and tagging genes/QTLs for different qualitative and quantitative traits and their use in marker-assisted selection have been presented. This progress not only addresses current challenges but also sets the stage for future research aimed at further optimizing productivity, oil quality, and resistance to pests and diseases in mustard cultivation.

Gene Action and Heterosis Studies for Yield and its Attributes in Bitter Gourd (Momordica charantia. L) under Temperate Ecologies

Thirty crosses developed through Line x Tester mating design along with their parents were evaluated for combining ability, heterosis and gene action for yield and its attributes in bitter gourd. The experimental material was evaluated in RCBD design with three replications at three different locations viz., Vegetable Experimental Farm, Division of Vegetable Science, SKUAST-Kashmir, Shalimar Srinagar (E1); Faculty of Agriculture, Wadura, Sopore (E2) and KVK Malangpora, Pulwama (E3). The mean squares due to parents vs crosses were significant for all the traits, which indicated the possibility of sufficient amount of heterosis exploitation for these traits. The \(\sigma\)2sca was found to be more than \(\sigma\)2gca for all the traits under study which indicated the preponderance of non-additive gene action for the traits. Both the variances (\(\sigma\)2gca and \(\sigma\)2sca ) were significant for most of the traits which reflects the importance of both additive and non-additive gene effects in the inheritance of these traits. The lines viz: NDBG-4, NDBG-1, NDBG-5, Pant Karela-1 and NDBG-7 were found to be good general combiners for most the economic traits. The extent of heterosis exhibited by crosses were estimated over standard parent (Arka Harit). The crosses viz: Pant Karela-1 × Arka Harit, NDBG-4 × Arka Harit, NDBG-1 × Arka Harit, NDBG-7 × Jounpuri, NDBG-5 × Jounpuri, NDBG-5 × Local bitter gourd, Pant Karela-1 × Jounpuri, NDBG-4 × Local bitter gourd and NDBG-4 × Local bitter gourd showed high standard heterosis for yield and yield attributes. These crosses can be exploited as desirable hybrids for yield.

Heterosis and inbreeding depression for grain yield and yield contributing characters in wheat (Triticum aestivum L.)

Heterosis and inbreeding depression for grain yield and yield contributing characters in wheat (Triticum aestivum L.)

Evaluation of seed yield, essential oil compositions, and fatty acid profiles in advanced fennel (Foeniculum vulgare Mill) breeding populations

Metabolites derived from bitter fennel serve as flavoring and healing agents in the pharmaceutical, food, and cosmetic sectors. Previously, we developed three fennel breeding populations (Early, Medium, and Late Maturity Synthetic Cultivars) with the potential to produce higher seed yield. This investigation aimed to assess the quality and quantity of the important metabolites in these three cultivars alongside their elite parental populations. Our results showed that the highest amounts of essential oil yield and seed yield were produced by, two breeding populations, Medium and Late Maturity Synthetic Cultivars. These cultivars showed positive seed yield heterosis rates of 28% and 20%, respectively, above the averages of their parental populations. GC-MS analysis of the essential oil samples identified 24 components in total. The major compounds in all genotypes were trans-anethole (34.09–77.84%), limonene (4.99–12.66%), methyl chavicol (1.35–38.69%), and fenchone (6–13.07%). The highest amount of trans-anethole belonged to Fasa and the Medium Maturity Synthetic with 77.84 % and 73.10%, respectively. The analysis of fatty acid compositions in the genotypes was conducted using GC-FID, which revealed the presence of 19 unique fatty acids, of which ten were saturated, and nine were unsaturated fatty acids. Petroselinic acid (67.11–78.44%), and linoleic acid (9.14–11.60%) were the major unsaturated fatty acids in fennel seeds. The Early Maturity Synthetic exhibited the least saturated fatty acid content (7.24%), while the highest levels of unsaturated fatty acids were found in both the Early Maturity Synthetic (89%) and Hashtgerd (88.55%). The genotypes were categorized into four groups using a heat map analysis with hierarchical clustering. Overall, the results showed that the three synthetic cultivars of fennel have outperformed the elite parental populations for seed and essential oil yields, concentration of the major industrial secondary metabolites such as trans-anethole, and higher proportions of unsaturated fatty acids. These cultivars show potential for usage in the pharmaceutical and healthcare industries.

Chromosome-scale genome assembly-assisted identification of Brassica napus BnDCPA1 for improvement of plant architecture and yield heterosis

Chromosome-scale genome assembly-assisted identification of Brassica napus BnDCPA1 for improvement of plant architecture and yield heterosis

Genetic Components Derived Parameters and Heterosis in Okra under Saudi Arabia Conditions.

Four parental genotypes of okra were crossed in complete diallel design to study the direction and extent of relative heterosis and heterobeltiosis for yield and its associated traits for utilization of existing genetic diversity to develop heterotic F1 hybrids in okra. The additive genetic component (D) was significant in all studied traits except average pod weight. Nonadditive (H1 and H2) components were found to be significant in all studied traits. However, the values of the dominant effect (H1) were smaller than the D components for no. of nodes/plant, no. of pods/plant, weight of medium pods, weight of large pods, and total fresh pod yield. The maximum significant MP heterosis in the desirable direction (149.9%) was recorded for the weight of large pods/plot. The maximum significant heterobeltiosis in the desirable direction (120.1%) was recorded for the weight of small pods/plot followed by total fresh pod yield (107.4%), the weight of large pods/plot (104.9%), weight of medium pods/plot (92.1%), average pod weight (51.8%), number of pods/plant (38.4%), and plant height (34.3%). It could be concluded that plant height, average pod weight, and the number of branches could be considered for the development of elite hybrids (heterosis breeding) or inbred lines (pure line selection) in succeeding generations. Therefore, these parameters can be considered for selecting genotypes to improve the pod yield of okra. The superior crosses identified through heterosis analysis were Egyptian Balady × Line 4.1.18 (30.8 ton/ha), Line 4.1.18 × Egyptian Balady (29.8 ton/ha), Dwarf Green Long Pod × Line 4.1.18 (28.3 ton/ha), and Egyptian Balady × Dwarf Green Long Pod (27.6 ton/ha) as these crosses had high performance as well as significant and higher estimates of heterobeltiosis for fruit yield per plant and yield attributing other characters.

Estimation of heterosis for yield and its contributing traits in Brassica juncea L.

Brassica is an economically important genus consisting of oilseeds, vegetables, and forage crops. Brassica juncea L. is commonly known as Indian mustard. The current investigation was carried out with ten diverse parents, and 45 crosses in a half-diallel mating design. A total of 55 genotypes (45 F1 + 10 parents) were investigated for 14 traits, yield, yield characters, and oil content during rabi 2021-22 and 2022-23. All crosses along with their parents were assessed in RBD with three replications. Analysis of variance for combining ability showed that significant variation was present among 45 crosses and their parents. The cross DRMRIJ-31× BRIJRAJ showed positive significant mid-parent heterosis (30.76%) and better parent heterosis (30.20%), while the cross DRMR150-35 × RH-406 showed positive significant economic heterosis over both the checks (44.68% and 35.25%) respectively. The best crosses for yield/plant NRCDR-02 x PUSABOLD, NRCDR-02 x RH-761, NRCDR-02 x JM-2 and NRCDR-02 x BRIJRAJ exhibited positive and significant heterosis. Hence, these identified hybrids could be used for exploitation of heterosis after evaluating and testing with large multilocations.

Adaptation and plasticity of yield in hybrid and inbred sorghum

AbstractLocal adaptation and genotype by environment (G×E) interactions affect the expression of phenotypes in crop species. An investigation on the interplay between adaptation and G×E on sorghum heterosis phenotypes is lacking. To address this question, a set of 112 diverse grain sorghum hybrids and their 22 inbred parents of local and exotic origins, representing the primary female and male heterotic groups, were tested in five contrasting sorghum‐growing environments across 2 years in Queensland, Australia. Plant height, days to flowering, seed yield, grain weight, and grain number were measured and used in the estimation of heterosis. Midparent heterosis for yield ranged from –25% to 217% and was highly influenced by grain number. In contrast to observations in maize, the magnitude of heterosis for yield was not associated with site mean. Striking differences were observed in heterosis in hybrids from locally developed inbred parents compared with hybrids that were developed from exotic inbred parents developed in other countries. Heterosis in the latter combination was higher on average across all the test environments for the majority of traits. We hypothesize maladaptive phenotypic plasticity in the exotic parents contributed to the observed differences in heterosis estimates. These data confirm that heterosis estimates in sorghum must be obtained and interpreted in relevant genetic and environmental contexts. Breeders in developing countries with low sorghum hybrid seed uptake will find these insights useful when selecting hybrids for broader adaptation, improving efficiency of their breeding programs.

Heterosis for yield and yield contributing characters under terminal heat stress in wheat (Triticum aestivum L.)

Heterosis for yield and yield contributing characters under terminal heat stress in wheat (Triticum aestivum L.)

Viability of simultaneously selecting for grain yield and seed physiological quality in maize

ABSTRACT: Currently, the demand is not only for more productive corn hybrids, but also for those with high physiological seed quality. Seed quality is considered the sum of genetic, physical, physiological and sanitary attributes that directly interfere in plant vigor. The objective of this study was to evaluate the physiological parameters of the seeds of parents and maize inter varietal hybrids obtained in a reciprocal recurrent selection program through physiological and image analysis techniques and either to study the feasibility of simultaneously selecting for seed physiological quality and grain yield. Two experiments were performed, one in the field and the other in the laboratory. The evaluated traits in the field were days of female flowering, days of male flowering, insertion of the 1st ear, plant height and grain yield. For the physiological quality, the attributes of germination at four days, germination at seven days, vigor by the cold test, emergence speed index, and the ratio of the root length to shoot length were obtained using GroundEye®. Heterosis was measured for the agronomic and physiological traits. Through the contrast between the inter varietal crosse hybrids and reciprocals we measured the maternal effect. The magnitudes of heterosis allowed us to infer that as greater as the number of selection and recombination cycles, on average, greater heterosis for the traits grain yield and seed germination. The correlated response indicated that, high yield intervarietal hybrids have better seed physiological quality.

Standard heterosis for yield and its attributing traits in brinjal (Solanum melongena L.)

Standard heterosis for yield and its attributing traits in brinjal (Solanum melongena L.)

Gene Effect Analysis for Grain Yield, Yield Components and Physiological Characters in Bread Wheat Under Water Limited Conditions of Bundelkhand Region

The present study was conducted during rabi, 2019-20 and 2020-21 with 08 bread wheat diverse parents and their 28 F1s (half diallel, excluding reciprocals) to study gene effects and heterosis for grain yield, yield attributes and physiological traits. Days to heading and days to maturity had general mean values of 89.8 days and 130.4 days, respectively. The parent GW 322 showed early heading in 88 days, while the genotype DBW 110 exhibited early maturity in 128 days. The hybrid NW 5054×PBW 723 (13.45 cm) had the highest spike length, followed by HD 3086×NW 5054 (13.40 cm) and PBW 723×NIAW 34 (13.25 cm). The grain yield per plant ranged from 17.37 g to 21.85 g in parents and 14.99 g to 23.41 g among hybrids. The cross HD 3086×K 1006 (23.41 g) and the parent HD 3086 (21.85 g) depicted the highest grain yield per plant. The parent NIAW 34 and the hybrid HD 3086×NIAW 34 showed the highest chlorophyll fluorescence. All three key physiological traits showed significant and positive associations with grain yield and harvest index. All the seventeen characters showed high GCA effects than SCA effects and indicated for preponderance of additive gene effects for yield, its components and physiological traits. An appraisal of GCA effects found that HD 3086 was a good general combiner for the majority of characters, while the crosses, HI 1544×NIAW 34, HI 1544×GW 322 and NW5054×PBW723 with significant SCA effects were found promising under water limited conditions of Bundelkhand region.

Study of heterosis for grain yield and its components in wheat (Triticum aestivum L. em. Thell.)

The extent of wheat heterosis was determined by synthesizing 45 hybrids in a 10×10 diallel method, eliminating reciprocals, to determine how widespread it is. The 57 entries that made up the experimental material—10 parents, 45 crosses and 2 checks (HD 3086 and UP 2628), were assessed over the course of rabi 2018–19 using a Randomized Block Design (RBD) with three replications, and observations were made for 12 characters. For yield and its component traits, analyses of heterosis over mid parent, better parent and two standard checks were conducted. ANOVA exposed that there was a high significance existed among all the genotypes for all the characters studied. Yield and its contributing traits have been evaluated for their maximum heterotic range. One cross i.e., CAL/NH//H567.71/3/SER1/4/CAL/NH//H567.71/5/2* KAU2/6/...×PBW 692 showed positive significance for relative heterosis, heterobeltiosis and standard heterosis over both checks for grain yield per plant. In terms of the number of productive tillers per plant and the number of grains per spike, UP 2901×QLD 73 was found to be a superior heterotic F1. By displaying a negative significant standard heterosis over both checks, the cross between CAL/NH//H567.71/3/SER1/4/CAL/NH//H567.71/5/2*KAU2/6/...×UP 2901 demonstrated its earliness. The desired significant relative heterosis, heterobeltiosis and standard heterosis for spike length were present in HD 3234×UP 2762. The finest heterotic cross combinations for harvest index were determined to be CAL/NH//H567.71/3/SER1/4/CAL /NH//H567.71/5/2* KAU2/6/...×UP 2762 and VORB/SOKOLL×QLD 73. Higher heterotic crossings may be used to identify transgressive segregants that will increase bread wheat production and yield-contributing characteristics.

Combining ability, heterosis and gene action for yield and its component traits incastor (Ricinus Communis L.)

An investigation on combining ability, heterosis and gene action for yield and its component traits in castor was carried out at AICRP Castor, UAS, Bangalore involving fifty hybrids developed from five pistillate lines as females and 10 testers as males. Analysis of variance revealed significant differences among parents and crosses for all yield attributing traits. The line YRCP-1 and tester RG-3160 showed significant positive effect for seed yield. The cross MCP-1×RG- 3160, expresses significant SCA effect for earliness, spike lengths, capsules on primary spike and seed yield/plant. Hybrids MCP-1 × RG-2787 (157.50 g) and DPC-22 × RG-2787 (186.77 g) involving poor performing parents produced high magnitude for seed yield/plant and yield attributing traits like 100 seed weight and oil percent (%).

Assessment of combining ability and heterosis for yield and its component traits in Indianmustard [Brassica juncea (L.) Czern and Coss.

Line × tester analysis was carried out to estimate heterosis and combining ability effects of 32 Indian mustard hybrids. Three lines, namely, RH 30-OA, RH 115-OA, and RH 832-OA, as well as two testers, Ogura 17 and Ogura 101 were discovered to be good general combiners with significant positive general combining ability (GCA) effects for seed yield/plant and component traits. Specific combining ability (SCA) effects for seed yield/plant were significantly positive for RH 30-OA × Ogura 101 and RH 832-OA × Ogura 72 crosses which exhibited significant economic heterosis compared to the standard check DMH 1.

Safflower heterosis for yield and its contributed characters

Twenty two hybrids were tested using line x tester design involving two cytoplasmic male sterile lines during rabi 2018, using Randomized block design with three replications. Twenty two along with three checks 'A-1,PBNS-12, PKV Pink' were evaluated at the field of Oilseeds Research Unit, Dr. PDKV, Akola during rabi 2019- 2020 to estimate extent of heterosis in safflower genotypes.Among all the crosses, AKS CMS 2A x GMU 1183 (46.15 % and 44.30%) exhibited highly significant and positive average heterosis for number of seeds/plant over mid and better parent. crosses, AKS CMS 2A x GMU 184 (49.26% and 34.44%) exhibited highly significant and positive average heterosis for 100 seed weight, whereas, cross AKS CMS 2A x GMU 5149 (15.28% and 9.32%) exhibited highly significant and positive average heterosis for volume weight. The highest heterosis and heterobeltiosis in desirable direction were recorded for seed yield/plant in AKS CMS 2A x GMU 1654 (246.96%) and the cross AKS CMS 3A x GMU 1183 (206.75%) showed highest and significantly positive standard heterosis over the checks i.e. PKV PINK, AKS 207 and PBNS-12.

Safflower heterosis for yield and its contributed characters

Safflower (Carthamus tinctorius L.) is one of the major edible oilseed crops grown in winter season in India. The first safflower hybrid released in India for commercial cultivation in all safflower growing regions was based on genetic male sterility system. Twenty two hybrids were tested using line x tester design involving two cytoplasmic male sterile lines during rabi 2018, using Randomized block design with three replications. Twenty two along with three checks 'A-1, PBNS-12, PKV Pink' were evaluated at the field of Oilseeds Research Unit, Dr. PDKV, Akola during rabi 2019-2020 to estimate extent of heterosis in safflower genotypes. Among all the crosses, AKS CMS 2A x GMU 1183 (46.15 % and 44.30%) exhibited highly significant and positive average heterosis for number of seeds per plant over mid and better parent. crosses, AKS CMS 2A x GMU 184 (49.26% and 34.44%) exhibited highly significant and positive average heterosis for 100 seed weight, whereas, cross AKS CMS 2A x GMU 5149 (15.28% and 9.32%) exhibited highly significant and positive average heterosis for volume weight. The highest heterosis and heterobeltiosis in desirable direction were recorded for seed yield per plant in AKS CMS 2A x GMU 1654 (246.96. %) and the cross AKS CMS 3A x GMU 1183 (206.75%) showed highest and significantly positive standard heterosis over the checks i.e. PKV PINK, AKS 207 and PBNS-12.Biotechnological tools, such as genetic engineering need to be perfected for incorporation of mitochondrial male sterility causing factor of sunflower into safflower to develop safflower hybrids which can be more easily produced.

Effects of temperature on fertility in hybrid hermaphroditic Argopecten scallops

Temperature is a critical factor affecting the growth, development and reproduction of aquatic organisms. The interspecific F1 hybrids between hermaphroditic bay scallops (Argopecten irradians) and Peruvian scallops (Argopecten purpuratus) exhibited significant heterosis in yield, but sterility in most hybrids hindered large scale interspecific hybridization and speciation. We first explored the physiological effect of temperature on the fertility of hybrid hermaphroditic Argopecten scallops with F1 hybrids treated at 6 different temperatures (18 °C, 20 °C, 22 °C, 24 °C, 26 °C, and 28 °C). The results showed that the final mortality rates from 18 °C to 22 °C were significantly lower than those from 24 °C to 28 °C. With the decrease of the temperature, the size, gonadal index, ATP content, and expression of most genes related to fertility regulation gradually decreased in F1 hybrids treated at 22 °C, 20 °C and 18 °C, and the apoptosis rate of oocytes gradually increased, but the activity of SOD (superoxide dismutase) and CAT (catalase) first increased and then decreased. The fertility of hybrids treated at 22 °C, 20 °C and 18 °C gradually decreased with the decrease of the temperature. According to gene expression, temperature may regulate the fertility of Argopecten F1 hybrids by affecting apoptosis, meiosis, ATP production and damage repair to inhibit the genesis and maturation of germ cells. Our findings suggest that temperature can affect the hybrid fertility of hermaphroditic Argopecten scallops and provide the basis for further research on the mechanism of temperature on sterility.

Studies on Heterosis for Yield and its Component Traits in Brinjal (Solanum melongena L.)

Studies on Heterosis for Yield and its Component Traits in Brinjal (Solanum melongena L.)

Integration of transcriptome and DNA methylome analysis reveals the molecular mechanism of taproot yield heterosis in radish (Raphanus sativus L.)

Heterosis, a crucial biological phenomenon, plays a vital role in determining the yield and quality of plants. Radish, an important root vegetable crop, exhibits notable heterosis in terms of root yield and quality. Nevertheless, the specific molecular mechanism behind the formation of heterosis in radish remains unclear. Herein, transcriptome and DNA methylome analyses were performed on F1 hybrids and parental lines. Expression level dominance (ELD) genes and allele-specific expression (ASEG) genes together significantly contribute to heterosis, primarily through energy metabolism and plant hormone signal transduction pathway. Additionally, an increase in the average methylation level in the F1 hybrids was observed compared to the parental lines. Interestingly, a negative correlation was found between the methylation level of differentially expressed genes (DEGs) in gene body regions and their expression levels in NAU-LB and the F1 hybrids. Conversely, a contrasting trend was observed between NAU-YH and the F1 hybrids. Furthermore, when the parental lines and the F1 hybrids were treated with 5-azacytidine, the hybrids were more sensitive to methylation inhibitors than their parents. A significant decrease was observed in root weight and total sugar content in the F1 hybrids compared to the control. Immunolocalization results indicated a significant decrease in the auxin content of the F1 hybrid under 5-azacytidine treatment. Proliferating cell nuclear antigen immunolocalization also revealed significant inhibition of vascular cambium activity in both the hybrids and parental lines. Notably, the expression profiles of a few differentially methylated DEGs including RsSUS1, RsSUC2a, RsIAA7, and RsIAA18, were significantly increased in the root of hybrids compared to their parents, suggesting a potential role for DNA methylation in yield heterosis. Collectively, these findings would provide valuable insight into the molecular mechanism underlying taproot yield heterosis and have the potential to facilitate the genetic improvement of taproot yield and quality in radish breeding programs.