[Some biological characteristics of genetically engineered insecticidal Pseudomonas fluorescens]

Plasmid stability, Antifungal activity, plant-colonizing ability, UV resistance and inseticidal activity in field were analysed for the engineered Pseudomonas fluorescens (Pf) strain IPP202. The results indicated that the recombinant plasmid in IPP202 was very stable after successive diluting culturing and after continuous culturing, There was no significant change in the properties beneficial to plants, such as antifungal activity and plant-colonizing ability as compared with the original strain P303. IPP202 was much more resistant to UV than Bt strain HD73. The control effect in field against cotton boll worm in field was close to that of a locally used Bt-chemical mixture in normal applied concentration. All the data indicated that the engineered Pf strain was a one with prosperous future after further study.