Chen F, Guo Y B, Wang J H, Li J Y, Wang H M
Department of Plant Pathology, China Agricultural University, Beijing 100094, PR. China.
Plant Dis. 2007 Aug;91(8):957-963. doi: 10.1094/PDIS-91-8-0957.
Crown gall induced by Agrobacterium vitis is a worldwide plant disease in grape-growing regions. Rahnella aquatilis HX2, a new isolate from vineyard soil in Beijing, showed a significant inhibition effect on the development of crown galls in grapevines. In field trials, immersion of the basal ends of grape cuttings with HX2 cell suspension inhibited or completely prevented crown gall formation caused by A. vitis K308 in the roots of the plants from the cuttings. The 3-year average disease incidence in grape plants treated with HX2 was 30.8% compared to 93.5% in plants without HX2. The culture supernatant of HX2 exhibited a stronger inhibition effect on disease development than did the cell suspension. HX2 could be found in the grape rhizosphere, grown under field conditions, for up to 90 days after inoculation. There was no significant difference in the mean population sizes of root microflora between plants treated and not treated with HX2. The inhibition effect of HX2 on crown gall in sunflower, caused by different agrobacterial strains, varied between 30.7 and 100%, depending on strains. Our results showed that Rahnella aquatilis HX2 may be used as a biological control agent for crown gall disease of grapes.
由葡萄土壤杆菌引起的葡萄冠瘿病是葡萄种植区一种全球性的植物病害。北京葡萄园土壤中分离出的一株新菌株——水生拉恩氏菌HX2，对葡萄冠瘿病的发展具有显著抑制作用。在田间试验中，用HX2细胞悬浮液浸泡葡萄插条基部，可抑制或完全阻止由葡萄土壤杆菌K308引起的插条植株根部冠瘿的形成。用HX2处理的葡萄植株3年平均发病率为30.8%，而未用HX2处理的植株发病率为93.5%。HX2的培养上清液对病害发展的抑制作用比细胞悬浮液更强。在田间条件下接种后长达90天内，均可在葡萄根际发现HX2。用HX2处理和未处理的植株根际微生物群落平均种群大小没有显著差异。HX2对不同土壤杆菌菌株引起的向日葵冠瘿病的抑制效果在30.7%至100%之间，具体取决于菌株。我们的结果表明，水生拉恩氏菌HX2可作为葡萄冠瘿病的生物防治剂。
