烟草黑胫病菌培养性状的研究

Cultural Characteristics of Phytophthora Nicotianae var. nicotianae,Pathogen of Tobacco Blank Shank

目的对烟草黑胫病菌的若干培养性状进行研究,进一步了解烟草黑胫病菌的培养特性的稳定性,为烟草黑胫病的相关研究和综合治理提供试验依据。方法从安徽10个主要生产烟草的市(县)多点采集发生烟草黑胫病的烟株,采用组织分离法进行病原菌分离,经纯化后获得69个烟草黑胫病菌(Phytophthora nicotianae Breda de Haan var.nicotianae Waterh.)菌株,对其进行游动孢子囊的诱导、配对培养、生长特性测定等进行研究。结果烟草黑胫病菌的主要培养性状为:异宗配合,与标准相对交配型菌株配对培养可以产生有性器官;卵孢子球形,满器或不满器,雄器围生,藏卵器小;孢子囊多近球形,乳突明显,有双乳突现象,孢子囊具脱落性,且孢子囊柄短,不对称孢子囊较常见,孢子囊外着生有长短不一的附属丝;菌丝最适生长温度为20～30℃,最高生长温度大于35℃,小于40℃,最低生长温度大于8℃,小于10℃。结论供试烟草黑胫病菌的培养性状与前人的研究结论基本一致,初步认为10多年来生态环境和农业措施的变化没有导致烟草黑胫病菌的生长性状发生较大的改变,表明烟草黑胫病菌的培养性状是较为稳定的。

[Objective] The study was conducted to observe culturaJ characteristics ofPhytophthora nicotianae Breda de Haan var. nicotianae The pathogenic microorganisms of tobacco blank shank, were studied to provide more information for integrated management of the disease. [ Method ] Sixty-nine isolates of the pathogen were obtained from diseased tobacco stem tissues collected from 10 localities in Anhui. Cultural characters of the isolates were studied by means of sporangium induction, partnership culture, morphological observation and growth property measurement. [Result] The results showed that these pathogenic microorganisms were heterothallic, with amphigynous antheridia and small oogonia, able to produce oospore when partnership culture with the standard opposite mating type isolates in vitro. They also showed that sporangia were mostly spherical or approximately spherical, conspicuously papillate or bipapillate, deciduous and with short caduceus. Some had hypha-like attachment filaments diverse in length and number. The asymmetry sporangia appeared frequently. The optimum temperature for mycelial growth was from 20℃ to 30℃, the maximum beyond 35℃ and below 40℃, and the minimum being between 8℃ and 10℃. [Conclusion] The research results showed that the culture characteristics of P. nicotianae var. nicotianae were mostly consistent with those reported former, suggesting that the change in ecological environment and agricultural measures had not let to the great change in culture characteristics in the past over ten years and that the characteristics of the pathogen was stable.