Volume 19 Part 1 Article 138
Title: On the usefulness of cytometric tools to select homokaryons in Agaricus bisporus
Author: M. Foulongne-Oriol, B. Buzzi-Amillano, M. Moinard, C. Spataro, S. Rousseau, S. Bitadeau, A. Rodier
Agaricus bisporus is one of the most commonly cultivated mushrooms worldwide. The current commercial cultivars are derived from a very narrow genetic basis. Despite its economic relevance, breeding efforts in this crop species are clearly hampered by its unfavorable life cycle equivalent to a pseudoclonal reproductive system. Most of the strains are bisporic with basides bearing a majority of heterokaryotic spores and a very small number of homokaryotic ones. A major bottleneck in the development of a breeding program for A. bisporus lies in the difficulty of isolating homokaryons (n) from heterokarons (n+n) among single spore isolates (SSIs). Several methods based on growth rate, fruiting ability or molecular markers are practiced, with, for each, their own drawbacks and limitations. Based on the difference in spore size between bisporic and tetrasporic A. bisporus strains (Callac et al. 2003), the aim of the study was to evaluate the usefulness of cytometric tools as a new method of isolating homokaryotic spores from SSI’s. While the feasibility of such an approach has been already demonstrated to characterize mushroom spores (Allman, 1992, Kullman et al. 2005, Veselska et al, 2014), to our knowledge, our work is one of the first attempt on A. bisporus.