충남 태안군 일대 4곳의 해안사구 지역에서 자생하는 9종의 사구식물 연관 근권세균 다양성을 2003년 10월부터 2004년 3월까지의 기간 동안 3차례에 걸쳐 denaturing gradient gel electrophoresis (DGGE) 기법을 이용하여 조사하였다. 그 결과 한 밴드가 계속 모든 시료에서 우점하는 것으로 나타났으며, DNA 염기서열 분석에 의하여 Lysobacter enzymogenes와 가장 유사한 것으로 나타났다. 기타 주요 밴

Indole-3-acetic acid (IAA) biosynthesis by bacteria occurs widely in rhizospheres. Bacterial species able to synthesize IAAmay be exploited for beneficial interactions in crop management systems. The objective of this study was to determine the response of ivyleaf morningglory (Ipomoea hederacea) seedlings to IAA and to an IAA-producing rhizobacterum, Bradyrhizobium japonicum isolate GD3. IAA solution and isolate GD3 suppression of seedling growth measured as radicle length and biomass depended on IAA concentration. Seedling radicle length was significantly reduced by ca. 29% with more than 1.0 ㎛ of IAA solution, compared to the control, 48 h after application. The cell concentration at 50% growth reduction (GR₅₀) of the seedling radicle was IAA production by isolate GD3 at 104.82 cfu, the cell concentration for 50% growth reduction (GR₅₀) of seedling radicle was 0.24 ìM, which was much lower than the IAA solution concentration (117.48 ㎛) required for GR₅₀. Therefore, excess IAA production by isolate GD3 may be more detrimental to morningglory radicle growth than standard IAA solution. Results confirmed involvement of IAA in suppressive effects of isolate GD3 on morningglory seedlings grown in a hydroponic system.