Hybrid Vigour and Hybrid Mimics in Japonica Rice

In crop improvement programs, hybrid vigour (heterosis) is an important breeding strategy but the molecular mechanisms of hybrid vigour are still unclear. Grain yield declines after F1 generation due to phenotypic segregation. We found that, at the early seedling stage in hybrids derived from the te...

Full description

Saved in:
Bibliographic Details
Published in:Agronomy (Basel) 2022-07, Vol.12 (7), p.1559
Main Authors: Zhang, You, Ovenden, Ben, He, Yao, Ye, Wenwei, Wu, Xianjun, Peacock, William James, Dennis, Elizabeth S.
Format: Article
Language:English
Subjects:
Biomass
Cereal crops
Cluster analysis
Crop improvement
Crop yield
Gas exchange
Germination
Germplasm
Grain
Heterosis
hybrid mimics
Hybrid vigor
Hybrids
Hypotheses
Inbreeding
Molecular modelling
Photosynthesis
Phylogenetics
Physiology
Plant reproduction
Rice
Seedlings
Seeds
Soil fertility
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:In crop improvement programs, hybrid vigour (heterosis) is an important breeding strategy but the molecular mechanisms of hybrid vigour are still unclear. Grain yield declines after F1 generation due to phenotypic segregation. We found that, at the early seedling stage in hybrids derived from the temperate japonica rice varieties ‘Doongara’ and ‘Reiziq’, hybrid vigour was approximately 40% greater than in the better parents. Inbred high-yielding lines (Hybrid Mimics) were developed from the ‘Doongara’ × ‘Reiziq’ F1 by selfing and recurrent selection for F1-like plants in the F2 through to the F5 generation. Grain yields are stable over subsequent generations in the Hybrid Mimic lines. The importance of photosynthesis in early seedling development was demonstrated. Photosynthesis-related genes were expressed in the hybrid earlier than in the parents; physiological evidence using gas exchange indicated the early commencement of photosynthesis. Dark germination experiments supported the requirement for photosynthesis for early vigour in hybrids.
ISSN:2073-4395
2073-4395
DOI:10.3390/agronomy12071559