National Center for Agricultural Utilization Research, USDA-ARS, 1815 N. University Ave., Peoria, IL 61604-3902, USA.
J Econ Entomol. 2013 Feb;106(1):57-63. doi: 10.1603/ec12226.
Technical improvements in the production and formulation of microbial agents will increase the potential for development of biological pesticides that are able to compete with chemical insecticides in the marketplace. Here we report the efficacy of a simple granule formulation containing microsclerotia of Metarhizium brunneum (Petch) (Hypocreales: Clavicipitaceae) for control of unfed and fed nymphs of Ixodes scpaularis Say (Acari: Ixoididae). Microsclerotial granules of M. brunneum applied to moist potting mix produce infective conidia within 2 wk and conidia remained viable for up to 8 wk after application. Microsclerotial granules produced from 3.05 x 10(9) to 1.24 x 10(10) conidia g(-1) granules in potting mix. Both unfed and fed nymphs were susceptible to infection when exposed to treated potting soil with up to 56 and 74% mortality, respectively. M. brunneum demonstrated a transtadial infection for fed nymphs exposed to treated potting mix with signs of a fungal infection becoming apparent only after molting into adults. High conidial production rates from microsclerotial granules of M. brunneum combined with significant tick mortality support the need for additional research to evaluate the efficacy of this treatment technology as a biopesticide option for control of ticks.
生产和配方技术的改进将提高微生物制剂的发展潜力，使其能够与市场上的化学杀虫剂竞争。在这里，我们报告了一种简单的颗粒制剂的功效，该制剂含有绿色木霉（Petch）（Hypocreales：Clavicipitaceae）的微菌核，用于控制未喂食和喂食的斑疹伤寒 Say 若虫（Acari：Ixoididae）。施用于湿润盆栽混合物的绿色木霉微菌核在 2 周内产生感染性分生孢子，并且在施用后长达 8 周内保持活力。从 3.05 x 10（9）到 1.24 x 10（10）个分生孢子/克颗粒在盆栽混合物中产生微菌核颗粒。未喂食和喂食的若虫在暴露于处理过的盆栽土壤中时都容易受到感染，死亡率分别高达 56%和 74%。感染过处理过的盆栽混合物的喂食若虫表现出跨龄感染，只有在蜕皮成成虫后才会出现真菌感染的迹象。绿色木霉微菌核颗粒的高分生孢子产量加上显著的蜱死亡率，支持需要进一步研究来评估这种处理技术作为控制蜱的生物农药选择的功效。
