Abstract:

The isolation method of Morchella strains directly affects the genetic stability, fruiting uniformity and yield of the strains. At present, the comparative study of different isolation methods of Morchella sextelata is still weak. In order to compare the effects of tissue isolation and multi-spore isolation on the cultivation performance of Morchella sextelata, and to evaluate the application potential of the two methods in strain breeding of morel, using the same fruiting body of Morchella sextelata as the test material, four strains were obtained by tissue isolation and multi-spore isolation, and their mycelial growth, bag-full time, fruiting phenology and yield were systematically determined. The results showed that all four strains contained both MAT1-1-1 and MAT1-2-1 mating-type genes, and the mycelial growth rate on PDA medium ranged from 14.1 to 15.2 mm/d without significant difference. The bag-full time of multi-spore isolated strain MS2 (26.5 d) was significantly shorter than that of tissue isolated strains TS1 (34.2 d) and TS2 (35.5 d). The interval from sclerotium to primordium of multi-spore isolated strains was shortened by about 2.5 d, and the first harvest time (73.3-74.0 d) was significantly earlier than that of tissue isolated strains (75.0-76.0 d). MS2 had the highest yield (0.45 kg/m²), which was significantly higher than that of TS1 and TS2, while MS1 had the lowest yield (0.35 kg/m²), showing significant differences among strains. Multi-spore isolation could produce greater phenotypic variation and screen out high-yield strains, but required strict selection. Tissue isolation had stable traits but low reproductive efficiency. Strain MS2 had excellent comprehensive characteristics and production application value. The results of this study can provide a scientific basis for the efficient strain isolation, breeding and stable cultivation of Morchella sextelata.

Key words: Morchella sextelata, tissue isolation, multi-spore isolation, mating-type genes, yield