2种水分条件下玉米苗期根系性状QTL分析

QTL mapping for root traits in maize seedling under two water supply conditions

利用DH1M×T877衍生的180个玉米RIL家系在正常水分和干旱条件下对苗期主胚根长、种子根长、种子根数、节根夹角、节根直径、节根根长和节根数7个根系性状进行QTL分析。结果表明:2种环境下共检测到51个QTL,正常水分条件下检测到31个QTL,干旱条件下检测到20个QTL,单个QTL可解释4.82%～17.14%的表型变异。干旱条件下,在第2和第3染色体上分别检测到1个控制多个性状的QTL;正常水分条件下,在第1和第7染色体上分别检测到1个控制多个性状的QTL;仅在第7染色体上检测到1个控制2种水分条件下种子根长度的QTL,而其余性状均未发现共同的QTL。

A recombinant maize inbred line(RIL)population with 180 lines derived from inbred lines DH1 Mand T877 were treated under well-watered(WW)and water stress(WS)conditions,seven root traits including the primary root length,seminal root length,seminal root number,crown root angle,crown root diameter,crown root length,and crown root number were measured and further used for QTL analysis.A total of 51 QTLs explained 4.82%-17.14%of phenotypic variance were identified,including 31 and 20 QTLs under well-watered and water stress conditions,respectively.Two QTLs with pleiotropic effects were identified on chromosome 2 and 3 under water stress condition.Two QTLs with pleiotropic effects were identified on chromosome 1 and 7 under well-watered condition.Only one QTL associated with primary root length on chromosome 7 were detected both under well-watered and water stress conditions.These results will be useful for improvement of maize root system and sought tolerance by molecular marker-assisted selection.