水稻不稔症之病因：無鞘腐病菌之長毛細蟎與水稻不稔症發生之關係

Abstract

水稻不稔症是因水稻葉鞘腐敗病菌(Acrocylindrium oryzae Sawada)及長毛細蟎(Steneotarsonemus spinki Smiley)的協力作用(synergism)之結果。雖然水稻葉鞘腐敗病菌主要造成水稻的褐化及穀粒的不稔，而長毛細蟎對水稻的直接傷害很小，僅幫助葉鞘腐敗菌的傳播及感染，但水稻不稔症病徵確需要葉鞘腐破病菌及長毛細蟎共同存在才能表現的。 長毛細蟎孤雌生殖之雄蟎後代具有生殖能力，且能與其親代母蟎交尾，而使母蟎新產生的卵，所孵伙出來的細蟎有雌雄蟎出現。 The etiology of rice sterile disease was certainly proved that the disease was caused by synergic effects of rice sheath rot fungus, Acrocylindrium oryzae Sawada, and rice tarsonemid mite, Steneotarsonemus spinki Smiley. Rice sheath rot fungus could primarily cause brown lessions and sterile grains and diseased rice plants. Although rice tarsonemid mites had a little damage on rice plants directly, the mites could carry the conidia of sheath rot fungus and help the fungus to infect rice plants. However, the syndrome appearance of rice sterile disease needed both rice sheath rot frungus and rice tarsonemid mites parasitize on rice plants togather. The parthenogenetic male progenies of rice tarsonemid mite had the reproduction ability, and could fertilized with their mother generation. Therefore, the mother mite fertilized by parthenogenetic male progenies reproduced both male and female mites in her new progeny generation.