Mapping Recombination Landscape and Basidial Spore Number in the Button Mushroom Agaricus bisporus

The button mushroom Agaricus bisporus is represented mainly by two varieties, a secondarily homothallic variety with predominantly heterokaryotic spores per basidia and heterothallic four homokaryotic spored basidium. Both varieties also differ in their recombination landscape the former showing crossovers (CO) at chromosome ends whereas latter has more evenly distribution of CO over chromosomes. are compatible, this been used to study segregation basidial spore number (BSN) genomic positions recombination, i.e., landscape, order find underlying genetic determinants. Knowledge on genes controlling might facilitate either conservation favorable allele combinations or disruption unwanted reduce linkage drag. For BSN, total seven QTL were found major 1 explaining ca. 55% phenotypic variation. It appeared, however, difficult map landscape. This phenotype can only be assessed meiotic offspring an intervarietal hybrid which laborious task. Nevertheless, was done, we able three QTLs for trait, one 2 not overlapping BSN. hurdles encountered discussed new strategy proposed that solves these. We propose use genetically unrelated mapping populations both cross between var. burnettii homokaryon thus segregating Homokaryotic intercrossed without limitation mating incompatibility marker homozygosity mushrooms directly these genotypes assess using next generation sequencing technologies will solve problems encountered, especially genotyping ends. approach useful efficient breeding general.