Abstract: In order to effectively prevent the mold mites Siteroptes reniformis from infecting cultivation objects， and consequently， control the pollution of symbiotic Nigrospora oryzae， we studied the effect of symbiont on development of the mite and selected methods for avoiding infection of the mite. It was found that the majority of mite S. reniformis carried one or two mould N. oryzae spores， the percentage was 31.6% and 49.1% respectively. By investigating the effect of mould N. oryzae on infection and development of mite on cultural medium， we found that mold mites infected culture successfully when mites and mould existed at the same time. Moreover， only N. oryzae stimulated the development of mould mite when mite was fed with seven mould. The mite completed development at the temperature from 16℃ to 30℃， and the developmental duration was the shortest 7.2±0.3 d at the temperature of 30℃. However， the size of suffulation body and the fecundity were the largest when the temperature was 16℃， which were 1.88±0.05 mm in diameter and 78.4±1.7 per female， respectively. By using different barrier method， it was showed that the glass jar brushed with mineral oil with screwed lids covered with preservative film or glass jar with the lid wraped over with Parafilm@ was the most effective way to prevent mites entering the culture jar. In conclusion， the symbiotic mould N. oryzae and the adaptive temperature were important for development of mite S. reniformis， and suitable barrier methods are also useful for controlling the mite.

Key words: tissue culture, Siteroptes reniformis, Nigrospora oryzae, fungal symbiont