辣椒疫霉菌产孢培养基及诱导方法筛选

Screening of Medium and Induction Method for Sporangia Production of Phytophthora capsici

为筛选适合辣椒疫霉菌产孢的培养基和诱导方法。通过计算游动孢子数量,研究比较不同培养基和诱导方法对辣椒疫霉菌产生孢子囊数量的影响。研究结果显示:CA培养基最适合孢子囊的产生,孢子囊密度为5.68×102/cm2,其次为RA培养基,PDA、BA和LA最不适合孢子囊的产生。采用创伤接种法,将辣椒疫霉菌菌丝体接种于20 d大小的黄瓜果实上,于28℃,24 h光照培养4 d后,黄瓜接种部位可产生病斑,病斑及周围产生密集菌丝,病斑上产生大量孢子囊,其产孢量为1.35×104/cm2,而同样接种方法的甜椒果实上所产生的孢子囊数量较少或不产生。不同诱导方法比较显示,日光照射受伤菌丝所产生的孢子囊数量高于菌丝块水培法。研究结果表明,CA培养基、创伤接种黄瓜果实和日光照射受伤菌丝适宜辣椒疫霉菌孢子囊的产生。

The effects of different media and induction methods on sporangia production of Phyophthora capsici were compared by calculating the sporangia yield in order to select the optimal medium and induction method for sporangia production of /9. capsici. The results showed that CA was the most suitable medium for sporangia production（5.68x102 sporangia/cm2）, followed by RA medium. PDA, BA and LA medium were not suitable for the sporangia production of P. capsici. Young cucumber fruit less than 20-day old was inoculated with the mycelia of P. capsici by wound inoculation method and cultured at 28 ~C with illumination for 4 days, the lesion was formed, and the mycelia developed around the lesion and produced plenty of sporangia（1.35x104 sporangia/cm2）, but no sporangia or less sporangia was produced on sweet pepper fruits by the same inoculation methods. In the comparison of different induction methods, irradiating wounded mycelia with white light induced more sporangia than that of mycelial plugs were incubated in water. The results indicated that CA medium, cucumber fruit inoculated with the mycelia by wound inoculation and irradiating wound mycelia with white light were suitable for the sporangia production of P. capsici.