茶薪菇‘赣茶AS-5’担孢子单核体菌株的交配型鉴定及菌丝生长速度

Mating type and mycelial growth rate of basidiospore-derived monokaryons of Cyclocybe chaxingu Gancha AS-5

摘要:

【背景】茶薪菇(Cyclocybe chaxingu)具有较高的食药用价值，加强优良菌种培育是推动茶薪菇产业发展的前提。杂交育种是目前食用菌育种常用的手段，单核体的获取及其交配型鉴定是杂交育种的基础性工作。【目的】开展茶薪菇单核体菌株的交配型鉴定，研究交配型对单核体菌丝生长速度的影响，为茶薪菇杂交育种提供理论依据。【方法】以茶薪菇‘赣茶AS-5’为研究对象，利用前期原生质体单核化获得的原生质体单核体菌株，进行互配确定标准测交菌株；收集‘赣茶AS-5’担孢子，将标准测交菌株与担孢子单核体配对及担孢子单核体互配后，进行担孢子单核体菌株交配型的分类；利用橡树木屑浸汁琼脂-榨橘汁(oak wood extract-squeezed orange juice, OWE-SOJ)琼脂培养基转换技术、核迁移及分子标记试验鉴定担孢子单核体的交配型；同时根据鉴定结果，随机选取不同交配型中可亲和的担孢子单核体进行杂交配对，考察其子实体形成情况。【结果】收集分离鉴定茶薪菇‘赣茶AS-5’的担孢子单核体共420株，交配型鉴定为T1、T2、T3和T4型的分别有69、126、148和77株，所占比例分别为16.43%、30.00%、35.24%和18.33%。OWE-SOJ技术、核迁移试验及分子鉴定交配型的结果一致，T1、T2、T3和T4的交配型分别为A1B1、A2B2、A2B1和A1B2，根据鉴定结果随机挑选的可亲和担孢子单核体杂交配对组合均可形成子实体。菌丝生长速度结果表明，A和B因子均显著影响担孢子单核体的菌丝生长速度，并且B因子对菌丝生长速度的影响效应大于A因子。【结论】OWE-SOJ、核迁移及分子标记技术均可准确鉴定茶薪菇担孢子单核体菌株的交配型，并且交配型存在偏分离现象，茶薪菇的单核体菌丝生长速度与交配型之间存在关联。

Abstract:

[Background] Cyclocybe chaxingu has high edible and medicinal values. Strengthening the breeding of elite strains is the premise for promoting the development of the C. chaxingu industry. At present, crossing is a common method in the breeding of edible fungi, and the acquisition of monokaryons and identification of the mating type is the basic work in the breeding of edible fungi. [Objective] To identify the mating type of C. chaxingu and evaluate the influence of mating type on the mycelial growth rate of monokaryons, thus laying a theoretical foundation for the crossing of C. chaxingu. [Methods] The protoplast monokaryons of C. chaxingu Gancha AS-5 were obtained by protoplast monokaryotation, and the standard tester strains were ascertained by mutual mating of monokaryotized protoplasts. Furthermore, basidiospores were collected. The basidiospore-derived monokaryons were matched with standard tester strains and with each other, respectively, and then the mating type of monokaryons was classified. The mating type of monokaryons was identified by oak wood extract-squeezed orange juice agar (OWE-SOJ), nuclear migration test, and molecular identification. [Results] A total of 420 monokaryons were collected and classified into four types, including 69, 126, 148, and 77 of T1, T2, T3, and T4, which accounted for 16.43%, 30.00%, 35.24%, and 18.33%, respectively. The results of OWE-SOJ, nuclear migration test, and molecular identification showed that the mating types of T1, T2, T3, and T4 were A1B1, A2B2, A2B1, and A1B2, respectively. The mating combinations of monokaryons randomly selected from the identification results could form fruiting bodies. Both A and B factors had significant effects on the mycelial growth rate of monokaryons, and the effect of B factor was greater than that of A factor. [Conclusion] OWE-SOJ, nuclear migration, and molecular techniques can accurately identify the mating type of monokaryons. Partial segregation appeared in the mating of monokaryons. There is an association between the mycelial growth rate and mating type of C. chaxingu monokaryons.