QTL Mapping And Analysis For Leaf Width And Length In The Maize (Zea Mays L.)

Maize(Zea mays L.) is an important food, feed and industrial material crops and China’s second largest food crop. Maize leaves are the most basic vegetative organs for photosynthesis, Leaf shape influences photosynthetic efficiency and plant type. Leaf width, leaf length directly determines the maize plant type, so it is of great importance for the research of maize leaf width and leaf length. In this study,325recombinant inbred lines derived from the cross B73×1212as the mapping population were constructed, the phenotypes of eight leaves were identified in2012and2013. In the research a linkage map which consist of208molecular makers was constructed.Then QTLs of leaf width and leaf length were identified primarily by ICIM mapping method, We have identified some important consistency QTLs for laying the foundation for the research of molecular mechanism of leaf width and leaf length traits and maize plant type improvement. The main results are as follows:1. A linkage map which consists of208molecular makers was constructed, covering the10chromosomes of the maize genome. Respectively the number of markers on chromosomes1,2,3,4,5,6,7,8,9,10are:19,31,18,18,20,17,17,34,17,17. The chromosome length Respectively are213.6,191.4,152.9,184,228.4,128.1,164.5,163,151.2,149.9cM,the map total length is1727cM, the average distance between markers is8.31cM.2. QTL mapping for the width of8leaves, two years we have detected many QTLs.. Consistency QTL controlling leaf width mainly located on chromosome4,5,6and8. The area between umc1309and Y144489on chromosome8controls the lth,2th,3th,4th leaf leaf in two years environment, PVE of this area for the2th,3th leaf leaf width stablely is15%,for the4th leaf leaf width is8%, the favorable allele from the male parent1212. Anoher area on chromosome5, bin5.03, nearest molecular makers is umc1852, controlls the lth,2th,3th,4th,5th,6th,7th leaf width,the average PVE for each leaf width respectively were8.86%,6.29%,12.47%,8.79%,10.95%,19.01%,18.97%,13.33%, the favorable allele from the female parent B73. The area between bnlg1023and umc1503on chromosome4controls the4th,5th,6th,7th,8th leaf width, the average PVE for each leaf width respectively are5.04%(only2012),6.99%,9.81%,9.65%,5.95%,in two years environment, the favorable allele from the female parent B73.3. QTL mapping for the length of8leaves, two years we have detected many QTLs. Consistency QTL controlling leaf length mainly located on chromosome1,2,5and8. The area on chromosome8bin8.03, nearest molecular makers is umc1236, controls the lth,2th,3th,4th,5th leaf length, favorable allele from the male parent1212, average PVE is about8%. Anoher area on chromosome5between umc2198and Y211642controls the lth,2th,3th,4th,5th,6th,7th,8th leaf length, the average PVE are5.40%(only2012),6.34%,7.62%,8.15%,9.62%,8.19%,5.75%,4.56%(only2013).