Intergenomic Interaction, Heterosis, and Improvement of Crop Yield

Srivastava, H. K.

doi:10.1016/s0065-2113(08)60886-x

Cited by 24 publications

(11 citation statements)

References 259 publications

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“…Thus, the conventional method of shuffling and recombining genes through heterosis breeding using the diverse ecogeographical genotypes/varieties offers a better option to generate new hybrid rice with superior grain quality. In such a hybrid, the positive aspects of performance both for grain yield and quality attributes are combined resulting in a genetic phenomenon called "hybrid vigour" or "heterosis" (Srivastava, 1981(Srivastava, , 1991 where young seedlings are highly vigorous and mature plants have better reproductive characteristics.…”

Section: Journal Of Sustainable Agriculturementioning

confidence: 99%

Governance of Gene Action and Combining Ability for Certain Grain Quality Traits in Three Diverse Rice (Oryza sativaL.) Growing Ecosystems

Verma

Santoshi

Srivastava³

2003

Journal of Sustainable Agriculture

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Traditional varieties or land races from diverse rice growing ecosystems serving as repository of desirable gene pools for rice improvement including rice hybrids have been marginalized or are at the verge of perhaps total genetic erosion. Biotechnology patent systems and intellectual property rights intrinsic with genetically engineered rices weigh in at odds, competing with these good grain qualified traditional rices. Genetic analyses have been made to uncover the supremacy of gene action and combining ability for certain grain quality related physicochemical traits in seven diverse ecogeographical genotypes of 'indica' rice using a 7 ϫ 7 half-diallel cross following Griffing's Model-1, Method-2. Comparative results obtained from 7 parents + 21 F 1 s + 21 F 2 s revealed the involvement of both additive (polygenic) and non-additive (epistasis or interallelic) gene action(s) in the governance of grain quality traits. However, the ratio of σ 2 g /σ 2 s exhibited greater importance O. P. Verma is affiliated with the New Delhi University of Agriculture and Technology, CRS, Ghaghraghat, Bahraich, India. of non-additive genes for all the traits except kernel length in F 1 . This suggests the plausibility of exploitation of heterosis in rice as a self-pollinated crop. Epistasis gene action (interallelic interaction) was found to be more pronounced for all the traits. The genotypes NS 19 (for grain weight), T 21 and IR 24 (for both kernel length and L/B ratio) and Jal Lahri (for protein content) emerged as good general combiners with high 'gca' values. The six specific crosses, viz., Mahsuri/IR 24, NDR 359/Jal Lahri, Sarjoo 52/Jal Lahri, Mahsuri/T 21, Sarjoo 52/NS 19 and Sarjoo 52/T 21, revealed significant 'sca' effects suggesting their role in improvising for certain physico-chemical grain quality traits. These crosses were found to retain at least one parent with high 'gca' value and the other parent having either high, average or low 'gca' effects indicating for the occurrence of both additive as well as non-additive genetic interactions. These findings may be of greater relevance in shuffling and combining the genes/traits between traditional and modern rice varieties (e.g., semi-dwarf, good to moderate tillering, medium maturity and good grain quality with high protein content) in almost all rice growing ecosystems.

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Section: Journal Of Sustainable Agriculturementioning

confidence: 99%

Governance of Gene Action and Combining Ability for Certain Grain Quality Traits in Three Diverse Rice (Oryza sativaL.) Growing Ecosystems

Verma

Santoshi

Srivastava³

2003

Journal of Sustainable Agriculture

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“…Despite the multiple cases where the bases of heterosis have been clarified, some authors have been searching for a ”unifying principle” [131], such as genome-wide changes in DNA methylation [132, 133], small RNA expression and epigenetic regulation [134–136], reduced metabolic cost of protein recycling in hybrids [137], gene dosage effects in macro-molecular complexes [138], enhanced metabolic efficiency due to weak co-aggregation of allozymes [139], organellar complementation [140] and phytohormonal expression [141]. These molecular processes may indeed distinguish heterozygotes from homozygotes, but if they were the general hidden causes of heterosis, correlations between levels of heterosis for different traits would be observed, and this has never been reported so far [142, 143].…”

Section: Discussionmentioning

confidence: 99%

Heterosis is a systemic property emerging from nonlinear genotype-phenotype relationships: evidence fromin vitrogenetics and computer simulations

Fiévet

Nidelet

Dillmann

et al. 2017

Preprint

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Heterosis, the superiority of hybrids over their parents for quantitative traits, represents a crucial issue in plant and animal breeding. Heterosis has given rise to countless genetic, genomic and molecular studies, but has rarely been investigated from the point of view of systems biology. We hypothesized that heterosis is an emergent property of living systems resulting from frequent concave relationships between genotypic variables and phenotypes, or between different phenotypic levels. We chose the enzyme-flux relationship as a model of the concave genotype-phenotype (GP) relationship, and showed that heterosis can be easily created in the laboratory. First, we reconstituted in vitro the upper part of glycolysis. We simulated genetic variability of enzyme activity by varying enzyme concentrations in test tubes. Mixing the content of ”parental” tubes resulted in ”hybrids”, whose fluxes were compared to the parental fluxes. Frequent heterotic fluxes were observed, under conditions that were determined analytically and confirmed by computer simulation. Second, to test this model in a more realistic situation, we modeled the glycolysis/fermentation network in yeast by considering one input flux, glucose, and two output fluxes, glycerol and acetaldehyde. We simulated genetic variability by randomly drawing parental enzyme concentrations under various conditions, and computed the parental and hybrid fluxes using a system of differential equations. Again we found that a majority of hybrids exhibited positive heterosis for metabolic fluxes. Cases of negative heterosis were due to local convexity between certain enzyme concentrations and fluxes. In both approaches, heterosis was maximized when the parents were phenotypically close and when the distributions of parental enzyme concentrations were contrasted and constrained. These conclusions are not restricted to metabolic systems: they only depend on the concavity of the GP relationship, which is commonly observed at various levels of the phenotypic hierarchy, and could account for the pervasiveness of heterosis. Author summary Heterosis, or hybrid vigor, is a genetic phenomenon that is widespread in the living world and is extensively exploited in domesticated species. First described more than 200 years ago, it has only been elucidated on a case-by-case basis. We propose a unifying principle of heterosis, hypothesizing that its pervasiveness reflects the general non-linearity of genotype-phenotype relationships. To corroborate this model, we first used theoretical developments that established the link between heterosis and the curvature of the genotype-phenotype relationship. Then we reconstituted in vitro a small metabolic pathway and mixed the content of different “parental” test tubes to simulate crossings. We showed that reaction rates in hybrid tubes were frequently faster than in parental tubes. The conditions for having heterosis were analyzed using computer simulations of this system, and proved to be direct consequences of the curvature of the enz...

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“…Hybrid vigor or heterosis resulting from genomic interactions can be used in the improvement of crop yield (Srivastava and Brady, 1981). As an allopolyploid species with three ancestral genomes, a high degree of intergenomic heterosis is expected in wheat .…”

Section: Future Workmentioning

confidence: 99%