Methods for mapping QTLs underlying endosperm traits based on random hybridization design

Several methods of interval mapping of QTLs underlying endosperm traits based on random hybridization designs and the triploid genetic model are proposed. The basic idea is: plants (or lines) from a population with known marker genotype information are randomly hybridized to generate a population of hybrid lines for endosperm QTL mapping; a mixture of seeds of each hybrid line is measured for the endosperm trait to get the mean of the line; then endosperm QTL mapping and effect estimation is performed using the endosperm trait means of hybrid lines and the marker genotype information of parental plants (or lines). The feasibility and efficiency of the methods are examined by computer simulations. Results show that the methods can precisely map endosperm QTLs and unbiasedly and efficiently estimate the three effects (additive effect, first dominant effect, second dominant effect) of endosperm QTLs.