EH Graham Centre for Agricultural Innovation (NSW Department of Primary Industries and Charles Sturt University), Yanco Agricultural Institute, Private Mail Bag, Yanco, NSW 2703, Australia.
J Invertebr Pathol. 2013 Jan;112(1):9-15. doi: 10.1016/j.jip.2012.10.006. Epub 2012 Nov 3.
A commercial formulation of Bacillus thuringiensis var. israelensis (B.t.i.) was evaluated for its potential to control chironomid midge larvae in newly sown rice crops in south-eastern Australia. Two replicated small-plot field trials were conducted using product application rates of 0.5-6 kg/ha. In trial 1 application rates between 2 and 6 kg product/ha all significantly (P<0.05) reduced populations of target Chironominae/Orthocladiinae by between 71% and 93% over the 19 day post-treatment monitoring period. Trial 2 was conducted using lower application rates (0.5-2 kg product/ha) and only the 2 kg product/ha rate significantly (P<0.05) reduced numbers of the target group (81% reduction) despite lower application rates resulting in target group suppression of 38-62%. Identification of larvae to species level from selected samples indicated that populations of Chironomus tepperi, the principal pest species that attacks the roots of rice seedlings, were reduced at all application rates; elimination of C. tepperi was achieved in trial 1 at an application rate of 2 kg/ha. Consistent with other studies, non-target Tanypodinae were not adversely affected by B.t.i., and in some treatments populations of Tanypodinae exceeded control levels by up to 73%. In the first trial, which was conducted under relatively high pest pressure, plant establishment was significantly (P<0.05) increased (120-157%) by Vectobac® WDG application rates of 2-6 kg/ha. No significant increase in plant establishment relative to the controls was identified in the second trial, when pest pressure was substantially lower and minimal damage occurred in the control bays. Overall, our results demonstrate that B.t.i. may be an economically viable alternative to broad-spectrum synthetic pesticides for the control of phytophagous midge larvae in establishing rice crops where members of the Chironominae, the group most susceptible to B.t.i., are the principal species of concern. The high specificity of B.t.i. for nematoceran Diptera should lead to reduced impacts on non-target organisms.
一种商业制剂的苏云金芽孢杆菌以色列变种（B.t.i.）被评估用于控制澳大利亚东南部新播种水稻作物中的摇蚊幼虫。使用 0.5-6 公斤/公顷的产品应用率进行了两次重复的小面积田间试验。在试验 1 中，2 至 6 公斤/公顷的产品应用率均显著（P<0.05）降低了目标摇蚊科/直翅目科的种群数量，在 19 天的处理后监测期间降低了 71%至 93%。试验 2 使用较低的应用率（0.5-2 公斤/公顷）进行，尽管较低的应用率导致目标组的抑制率为 38-62%，但只有 2 公斤/公顷的产品应用率显著（P<0.05）降低了目标组的数量（减少 81%）。从选定的样本中鉴定幼虫到种水平表明，攻击水稻幼苗根系的主要害虫种 Chironomus tepperi 的种群减少了，在所有应用率下都减少了；在试验 1 中，以 2 公斤/公顷的应用率消灭了 C. tepperi。与其他研究一致，非目标 Tanypodinae 不受 B.t.i.的不利影响，并且在某些处理中，Tanypodinae 的种群数量超过对照水平高达 73%。在第一次试验中，在相对较高的害虫压力下进行，Vectobac® WDG 的应用率为 2-6 公斤/公顷显著（P<0.05）增加了（120-157%）植物的建立。在第二次试验中，由于害虫压力显著降低，对照区几乎没有发生损害，因此相对于对照区，植物的建立没有显著增加。总的来说，我们的结果表明，在建立水稻作物时，B.t.i.可能是一种经济可行的替代广谱合成农药的选择，用于控制植食性摇蚊幼虫，其中最易受 B.t.i.影响的摇蚊科是主要关注的物种。B.t.i.对双翅目线虫目昆虫的高度特异性应该会减少对非目标生物的影响。
Zotero 插件