Genetic Analysis And QTL Mapping Of Spike Associated Traits In Wheat

Wheat is one of the most important crop plants in the world.The spike associated traits are important agronomic traits.It is of great value to understand their molecular genetic regulation and select them effectively for genetic and plant breeding purpose. These traits are quantitative and controlled by multiple genes. With conventional breeding methods, the selection efficiency of these traits is low. The advent of molecular markers and QTL(quantitative trait loci) mapping has made it possible to localize individual genes for this type of trait.The study were carried out by using SSR markers and a wheat DH populations, including 133 families,derived from anther culture from the F₁ of a cross between "zhengzhou 8761×chuanyu 35050". Spike associated traits ,such as plant height, internodal below spike, spike length, number of spikes, fertile spikelets per spike, sterile spikelets per spike and so on,were measured. The aims were to do genetic analysis about several traits of DH population ,construct molecular linkage map ,identify QTL and evaluate these effects using composite interval mapping. These works will do great help to fine mapping for QTL,map-based cloning of these genes,and maker-assisted selection.The main results were as follows:1. Genetics analysis of quantitative traits were carried out by using the investigated results in the normal irrigate and fertilize condition in 2004.Analysis the variance of differences between the parental groups on ten traits in the experiments showed significant difference between the plant height, internodal below spike, spike length, number of spikes, sterile spikelets per spike, spikelets per spike. Analysis the frequency distribution of each phenotype trait in DH population by SPSS,the test showed that all traits approximately fit normal distributions. Quantitative genetic analyses of wheat were carried out .It was shown that the heritability of plant height, internodal below spike, spike length, number of spikes, fertile spikelets per spike, sterile spikelets per spike, spikelets per spike, grains number per spike were respectively 92%, 83%, 79%, 30%, 48%, 48%, 53% and 47%. The number of segregating genes of those characteristics were 4.92, 6.02, 10.31, 11.56, 10.57, 10.49,...