Characteristics and breeding of a new cultivar of Pleurotus ostreatus 'Soltari'

Abstract

Oyster mushrooms are widely cultivated and consumed in Korea. P. ostreatus 'Suhan(ASI 2504)' is an ideal cultivar for mushroom farmers due to its dark pileus and thick stipe; however, as it is very sensitive to environmental conditions, an alternative cultivar is required. To develop a new cultivar, parental strains 'Suhan(ASI 2504)' and 'ASI 0665 (Heuktari)' were selected from various collected strains according to morphological characteristics. P. ostreatus 'Soltari' was developed by DiMon crossing between the dikaryotic strain 'Suhan' and the monokaryotic strain derived from 'Heuktari'. Thirty-eight of the 100 crossed strains were selected following analysis of mitochondrial genetic characteristics, and 'Soltari' was ultimately selected by continuous cultivation tests. The mitochondrial DNA profile of 'Soltari' was found to be the same as that of 'Heuktari, and a nuclear DNA profile of 'Soltari' was similar as those of the parental strains, 'Suhan' and 'Heuktari.' 'Soltari' mycelium grows adequately in moderate to high temperatures of 12-20 o C, although its optimum temperature was found to be 30 o C. Fruiting body production per 1.1-L cultivation bottle was approximately 158.8 g. Its stipe length and thickness were comparable to those of diameter and thickness were somewhat lower (42.72 vs. 51.33 mm and 18.18 vs. 22.46 mm, respectively). 'Soltari' was found to be more resistant to high CO 2 atmosphere than 'Suhan', and the color of the pileus of 'Soltari' was dark gray at high temperature. Therefore, it is suggested that this new cultivar 'Soltari' is a good alternative cultivar and will contribute to energy saving in oyster mushroom farms.