Department of Plant Protection, Faculty of Agricultural Sciences, Aligarh Muslim University, Aligarh, India.
J Appl Microbiol. 2021 Feb;130(2):424-438. doi: 10.1111/jam.14788. Epub 2020 Aug 12.
To ascertain the effectiveness of Aspergillus niger, Trichoderma harzianum, Pochonia chlamydosporia, Bacillus subtilis and Pseudomonas fluorescens against rice root-knot nematode, Meloidogyne graminicola, and to optimize their application methods.
The relative effectiveness of five indigenous biocontrol agents (BCA) against M. graminicola on rice cv. PS-5 was tested initially in pot culture. The BCAs, A. niger, P. chlamydosporia and P. fluorescens proved more effective, and significantly reduced the nematode disease. It is hypothesized that success of a biocontrol module may vary with the BCA and application methods. Hence, the effectiveness of the above three BCAs as well as seven different treatment schemes were evaluated in naturally infested farmer's fields during 2 consecutive years. In nematode-infested plots without any BCA treatments, terminal galls formed on the roots, and plants suffered a 19-31% decrease in the growth and yield. The treatments with P. chlamydosporia or A. niger through root-dip (RD) plus one soil application (SA) at 15 days after planting were found to be highly effective against the nematode.
Relatively greater nematode control was achieved with RD plus two SAs (15 + 30 DAP) but statistically the effect was on par with RD + one SA at 15 DAP. These treatments significantly reduced galling (22-25%), egg mass production (21-29%) and reproduction factor (63-70%) of M. graminicola, and subsequently increased the grain yield (11-21%).
Application methods enhanced the effectiveness of BCAs against M. graminicola. The RD plus one SA at 15 DAP proved to be most effective treatment to control root-knot disease in rice. Use of multiple treatments (root dip and SA) appears cumbersome, but in view of effectiveness and limitation of chemical control in rice paddies, farmers may adopt the above module that may lead to 11-21% yield improvement.
确定黑曲霉、哈茨木霉、厚垣轮枝孢、枯草芽孢杆菌和荧光假单胞菌防治水稻根结线虫、禾谷根结线虫的效果，并优化其应用方法。
最初在盆栽试验中测试了五种本土生物防治剂（BCA）对水稻品种 PS-5 上禾谷根结线虫的相对有效性。结果表明，黑曲霉、厚垣轮枝孢和荧光假单胞菌更有效，能显著降低线虫病害。假设生物防治模块的成功可能因 BCA 和应用方法的不同而有所不同。因此，在连续两年的自然感染农民田间，评估了上述三种 BCA 以及七种不同处理方案的效果。在没有任何 BCA 处理的线虫感染地块中，根部形成了末端瘤，植株的生长和产量减少了 19-31%。通过根浸（RD）加种植后 15 天进行一次土壤施用（SA）处理厚垣轮枝孢或黑曲霉的方法对线虫非常有效。
RD 加两次 SA（15+30 DAP）处理相对能更好地控制线虫，但在统计学上，其效果与 RD 加一次 SA 在 15 DAP 时相当。这些处理显著降低了禾谷根结线虫的瘤发生率（22-25%）、卵块产量（21-29%）和繁殖系数（63-70%），进而增加了稻谷产量（11-21%）。
应用方法增强了 BCA 对禾谷根结线虫的防治效果。在 15 DAP 时进行 RD 加一次 SA 处理被证明是控制水稻根结线虫病最有效的方法。使用多种处理方法（根浸和 SA）可能看起来繁琐，但考虑到稻田中化学防治的有效性和局限性，农民可能会采用上述模块，这可能导致 11-21%的产量提高。
