Response of wetland rice to inoculation with azospirillum lipoferum and pseudomonas sp

Abstract

N2-fixing Pseudomonas sp. (H8) and Azospirillum lipoferum (34H) which were isolated from wetland rice were inoculated separately in wetland rice in pots containing an Ultisol. The root portion of a rice seedling was dipped overnight into the bacterial suspension and transplanted. Ten days after transplanting the bacterial suspension was inoculated into the soil. The inoculation promoted early tillering and reproductive growth of wetland rice. It significantly increased the filling rate of grains and grain weight per plant at harvest. But no increase of total dry weight and N content was observed. Inoculation increased acetylene reduction activity and the number of N2-fixing bacteria associated with roots at early flowering stage. In pots applied with labeled ammonium N (75 mg N/pot), 15N contents in various plant parts and in the whole plant at harvest were not decreased by inoculation, except in culms of Azospirillum-inoculated plants. © 1984 Taylor & Francis Group, LLC.