Genetic dissection of the developmental behaviours of plant height in wheat under diverse water regimes.
Plant height (PH), a crucial trait related to yield potential in crop plants, is known to be typically quantitatively inherited. However, its full expression can be inhibited by a limited water supply. In this study, the genetic basis of the developmental behaviour of PH was assessed in a 150-line wheat (Triticum aestivum L.) doubled haploid population (Hanxuan 10 x Lumai 14) grown in 10 environments (year x site x water regime combinations) by unconditional and conditional quantitative trait locus (QTL) analyses in a mixed linear model. Genes that were expressed selectively during ontogeny were identified. No single QTL was continually active in all periods of PH growth, and QTLs with additive effects (A-QTLs) expressed in the period S1|S0 (the period from the original point to the jointing stage) formed a foundation for PH development. Additive main effects (a effects), which were mostly expressed in S1|S0, were more important than epistatic main effects (aa effects) or QTL x environment interaction (QE) effects, suggesting that S1|S0 was the most significant development period affecting PH growth. A few QTLs, such as QPh.cgb-6B.7, showed high adaptability for water-limited environments. Many QTLs, including four A-QTLs (QPh.cgb-2D.1, QPh.cgb-4B.1, QPh.cgb-4D.1, and QPh.cgb-5A.7) coincident with previously identified reduced height (Rht) genes (Rht8, Rht1, Rht2, and Rht9), interacted with more than one other QTL, indicating that the genetic architecture underlying PH development is a network of genes with additive and epistatic effects. Therefore, based on multilocus combinations in S1|S0, superior genotypes were predicted for guiding improvements in breeding for PH.
Wu
Xianshan
X
National Key Facility for Crop Gene Resources and Genetic Improvement/Key Laboratory of Crop Germplasm and Biotechnology, Ministry of Agriculture/Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
Wang
Zhenghang
Z
Chang
Xiaoping
X
Jing
Ruilian
R
D001947:Breeding; D018507:Gene Expression Regulation, Developmental; D006238:Haploidy; D040641:Quantitative Trait Loci; D014908:Triticum / Q000235:genetics* / Q000254:growth & development* / Q000378:metabolism; D014867:Water / Q000378:metabolism*
D014867:Water