Identification and validation of a locus for wheat maximum root length independent of parental reproductive environment

https://www.frontiersin.org/articles/10.3389/fpls.2022.999414/full

Frontiers in Plant Science，13:999414，doi: 10.3389/fpls.2022.999414 （2022）

Huangxin Chen1,2†,Conghao Zhao1,2†,Yaoyao Yang1,2,Zhaoyong Zeng1,2,Wei Li1,2,Yanlin Liu1,2,Huaping Tang1,2,Qiang Xu1,2,Mei Deng1,2,Qiantao Jiang1,2,Guoyue Chen1,2,Yuanying Peng1,2,Yunfeng Jiang1,2,Yun Jiang3,Yuming Wei1,2,Youliang Zheng2,Xiujin Lan1,2andJian Ma1,2*

Abstract

Maximum root length (MRL) plays an important role in the uptake of nutrients and resisting abiotic stresses. Understanding the genetic mechanism of root development is of great significance for genetic improvement of wheat. Previous studies have confirmed that parental reproductive environment (PRE) has a significant impact on growth and development of the next generation in the whole life cycle of a given plant. In this study, a recombinant inbred line population genotyped using the Wheat55K SNP array, was used to map quantitative trait loci (QTL) for wheat seedling MRL based on the harvested seeds from five different PREs. A total of 5 QTL located on chromosomes 3D and 7A were identified. Among them,QMrl.sicau-2SY-3D.2located in a 4.0 cM interval on chromosome 3D was likely independent of PREs.QMrl.sicau-2SY-7A.2was detected in two tests and probably influenced by PREs. The effect ofQMrl.sicau-2SY-3D.2was further validated using the tightly linked kompetitive allele specific PCR (KASP) marker,KASP-AX-111589572, in populations with different genetic backgrounds. Lines with a combination of positive alleles fromQMrl.sicau-2SY-3D.2andQMrl.sicau-2SY-7A.2have significantly longer MRL. Furthermore, four genes (TraesCS3D03G0612000,TraesCS3D03G0608400,TraesCS3D03G0613600, andTraesCS3D03G0602400) mainly expressed in wheat root were predicted to be associated with root growth. Taken together, this study reports on a major QTL independent of PREs and lays a foundation for understanding the regulation mechanism of wheat MRL at the seedling stage.