Kumari N Swarna, Sivakumar C V
Tamil Nadu Agricultural University, Coimbatore - 641003, India.
Commun Agric Appl Biol Sci. 2005;70(4):905-8.
The efficacy of the obligate bacterial parasite, Pasteuria penetrans against the rootknot nematode, Meloidogyne incognita infestation was assessed in brinjal. The seedling pans with sterilized soil were inoculated with nematodes and root powder of P. penetrans were applied at different dosages viz., 0 x 10(6), 0.5 x 10(6) spores and 1 x 10(6) spores/pan. Seeds of brinjal cv Co2 were sown in the pans and seedlings were allowed to grow. The seedlings were transplanted to microplots containing sterilized soil. Observations on nematode infestation and plant growth were recorded at seedling, flowering, and fruiting stages. Nematode infestation was significantly reduced by P. penetrans treatment. There was 22, 75 and 86% reduction in nematode population of soil over control at seedling, flowering and fruiting stages, respectively, at higher spore density (1 x 10(6)). Egg mass production was decreased by 63, 78 and 89% over control at 35 (seedling), 100 (flowering) and 160 (fruiting) days after sowing respectively, at 1 x 10(6) spores treated soil. The parasitizing ability of P. penetrans increased with the age of the crop. At higher spore density the percentage of parasitization was increased from 52.0 (35 days after sowing) to 90.0 (160 days after sowing) %. At these stages of the crop, the spore load per juvenile also increased at the higher dose. The P. penetrans application enhanced the plant growth. The weight of the shoot was increased by 17.6% whereas root weight by 41.0% over the control at fruiting stage. The experimental results revealed the potential use of P. penetrans as biological control agent of M. incognita. Application of P. penetrans spores in the nursery is a good strategy since the mass multiplication is quite difficult.
在茄子中评估了专性细菌寄生虫穿透巴氏杆菌对根结线虫南方根结线虫侵染的防治效果。将装有灭菌土壤的育苗盘接种线虫，并以不同剂量施用穿透巴氏杆菌的根粉，即每盘0×10⁶、0.5×10⁶和1×10⁶个孢子。将茄子品种Co2的种子播于育苗盘中，让幼苗生长。将幼苗移栽到装有灭菌土壤的小区中。在幼苗期、开花期和结果期记录线虫侵染和植株生长情况。穿透巴氏杆菌处理显著降低了线虫侵染。在较高孢子密度（1×10⁶）下，在幼苗期、开花期和结果期，土壤中线虫数量分别比对照减少了22%、75%和86%。在播种后35天（幼苗期）、100天（开花期）和160天（结果期），经1×10⁶个孢子处理的土壤中，卵块产量分别比对照减少了63%、78%和89%。穿透巴氏杆菌的寄生能力随作物年龄增加而增强。在较高孢子密度下，寄生率从播种后35天的52.0%增加到播种后160天的90.0%。在作物的这些阶段中，较高剂量下每个幼虫的孢子负载量也增加。施用穿透巴氏杆菌促进了植株生长。在结果期，地上部重量比对照增加了17.6%，而根部重量增加了41.0%。实验结果揭示了穿透巴氏杆菌作为南方根结线虫生物防治剂的潜在用途。由于大量繁殖相当困难，在苗圃中施用穿透巴氏杆菌孢子是一种很好的策略。
