Selecting Of 14 Pleurotus Eryngii Parent Strains And The Predicting Of The Heterosis Of F1 Generation Strains

The crossbreeding was a method to attain gene recombination by the combinations pairing of monokaryotic mycelium. Seen from the status quo of breeding in some developed countries, crossbreeding was one of the best effect methods in breeding and has been using most widely. P. eryngii was a kind of rare and advanced fungi which will have a development planning. Study on the p. eryngii cultivation has been performed more wide than crossbreeding, it is important to attain p. eryngii strains with properties of good quality, high-yield and vigorous adaptability.In this experiment, 14 p.eryngii strains were used as testing material. Monokaryotic mycelium was attainted by sing-spore isolation of strains which had different desirable characteristics, then they were paired. New varieties which coincided with people's need were attained by recombination of genetic material and generalization of desirable characteristics.The mycelium growth state, the agronomic characteristics of fruitbodies, nutritive ingredient, early maturity characteristics and the yield of 14 p.eryngii strains were compared. The results showed that the higher yield of these strains were PL 14, PL 17 and PL15; the economic properties of PL 15, PL 16, PL 17 and PL3 strains were better than other strains; the mycelia rate of PL2 and PL 12 mother cultures grew faster than others at 24℃; the higher resistant strains were PL 14, PL7 and PL11; the premature cultivated variety was PL14.Esterase isozyme of mycelia of 14 p.eryngii strains were studied by orthogonal slab polyacrylanide gel electrophoresis, the genetic variance and genetic relationship of strains were studied with esterase isozyme techniques and cluster method. The results showed that there was plentiful expression on isozyme band at 0.672 of Rf value. But it was different in the numbers of isozyme bands, position and enzyme activity, individual strains had its peculiar bands. The similarity coefficient of these strains ranged from 0.333 to 1.000. There were various degrees of genetic diversity, however in terms of all the strains tested the degree of genetic variability as a whole was not so plentiful. It indicated that germplasm of p.eryngii was diverse, on the same time, there were no positive connection on one certain degree between the geographical distribution and the genetic variance.Cluster analysis based on the coefficient of genetic similarity in the tested strains of p.eryngii was carried out by UPGMA. The results showed that the heterosis was stronger when the cross combinations were produced by most of parent strains in different groups, while the heterosis was weaker when the cross combinations were produced by parent strains in the same group. So parent strains in different groups should be selected in thecrossbreeding. Ninety-five cross combination were obtained through monospore crossbreeding. When mutually complementary enzyme bands and new enzyme bands of the new cross combinations appeared twenty-two crossbreeding filial generation by comparison of enzyme bands between parent strains and cross combinations, the heterosis of the crossbreeding filial generation was stronger and high quality strains could be select easily.