Mapping And Analysis Of QTLs For Maize Leaf - Related Traits

Maize(Zea mays L.) is an important food, feed and Economy crops worldwide, especially as the largest crop in China. Maize leaves, as the most basic vegetative organs for photosynthesis, the photosynthetic efficiency and plant type were influenced by Leaf type, which is directly determined by Leaf shape, leaf length,Leaf width, Leaf area, as well as Leaf angle. In addition, its related traits is a quantitative character controlled by polygenes, with complex genetic mechanism and lower heritability, thereby can be easily affected by environment. Therefore, it is of great importance for the research of maize Leaf type related traits. In this research,a new genetic linkage association with the Leaf type related traits was constructed based on IBM Syn10 DH population Binmap. Complete interval mapping(CIM) were used to QTL mapping for phenotypic traits in three environmental, such as Chongzhou, Xishuangbanna and Harbin, we aimed to demonstrate the regulatory mechanism for Leaf type related traits and laid the foundation for the research of molecular mechanism of Leaf type related traits and maize plant type improvement. The main results are as follows:1. In this study, phenotypic data from Xishuangbanna and Sichuan Chongzhou, Heilongjiang Haerbin were collected and analyzed using IBM Syn10 DH population, combined analysis of variance showed that there was no significance difference between these groups, while the difference among families, environments, and families x environments were significant, indicating that Leaf type related traits were susceptible to impact by environmental factors.2. Phenotypic analysis and the mean value for four Leaf type related traits in IBMSynlO DH population among Haerbin, Chongzhou, Xishuangbanna were analysed. The results showed that the leaf type related phenotypic data showed a continuous variation and a normal distribution basically. Correlation analysis results demonstrated that leaf type related traits correlations with each other in three locations.3. using the QTL IciMapping Version 4.0, genetic linkage map contained 5935 Binmarker were reconstructed, The results showed that total map length was 1767.45cM, Chromosome length ranged from 119.51 cm to 263.57 cM, and the average genetic distance between adjacent markers was 0.30 cM.4. Phenotypic data for leaf type related traits were collected and QTL analysis were conducted using QTL IciMapping V4.0 software, with complete interval mapping QTL mapping methods. Under three environmental conditions,52 corn leaf type related traits QTL were detected, such as 12 QTLs,9 QTLs,17 QTLs and 16 QTLs related to leaf angle,leaf length, leaf width and leaf area respectively. Among them, Among them,4 QTLs including qLL-2-1 for leaf length, qLW-2-2,qLW-6-3 for leaf length,qLA-5-2 for leaf angle were detected two or three times in the three environments, located in the same loci with other report within a smaller region. Meanwile, there were also some QTLs which havn’t reported before, like qLL-1-1 for leaf length、qLAr-1-1 for leaf area、qLAr-2-1 for leaf area, qLA-7-1 for leaf angle. In this study, all the detected QTL for the leaf traits provided support for gene cloning and research on leaf traits,At the same time, Provide a theoretical basis for molecular marker-assisted breeding plant type.