新月弯孢菌nit突变体的诱导与鉴定

采用硝酸盐缺陷型(nit)突变体互补测试法,对来自不同地区的5株新月弯孢菌Curvularialunata(wakker)Boed]菌株进行诱导与鉴定。通过对菌落生长量的测定表明,WAC培养基比KPS培养基更能抑制菌落的生长。将从两种诱变培养基中获得的抗氯酸盐突变体,同时接种到查彼克(Czapek)、CDA和MM培养基上进行鉴定。结果表明,经KPS诱变获得的nit突变体频率为15.40%,而经WAC诱变获得的nit突变体频率为24.73%。在获得的602个nit突变体中,由CDA、Czapek和MM分别鉴定出363个、184个和55个。用WAC-CDA组合筛选获得48.47%的NitM突变体,而其他组合的NitM突变体获得率均小于7.00%。表明WAC-CDA组合适合用于新月弯孢菌nit突变体的诱导与鉴定。

Recovery and Identification of nit Mutants of Curvularia lunata

Five strains of Curvularia lunata isolated from infected corn leaves collected from different regions in China are selected to test recovery and identification of nitrate-nonutilizing (nit) mutants. The colony’s growth of C.lunata is more restricted on WAC (water agar chlorate medium containing two point five percent KClO_3) medium than KPS (potato sucrose agar containing two point five percent KClO_3) medium. Three thousand chlorate-resistant sectors are identified on three different media which are used to assess nit mutants types. Two hundred and thirty one nit mutants (fifteen point four percents of all tested chlorate-resistant mutants) come from KPS. Three hundred and seventy one nit mutants (twenty four point seven three percents of all tested chlorate-resistant mutants) come from WAC. Among sixty hundred and two nit mutants, three hundred and sixty three are obtained from CDA (Czapek-Dox agar medium), one hundred and eighty four from Czapek, and fifty-five from MM (minimal medium). Forty eight point four seven percents NitM mutants are induced into combination of WAC and CDA medium, but the percentage of NitM mutants obtained from other medium combinations is less than seven percents. The results show that combination of WAC and CDA medium is more effective for recovery of nit mutants of C.lunata.