A cocktail1 of compounds emitted by the beneficial fungus2(真菌) Muscodor albus may offer a biologically based way to fumigate3(熏蒸) certain crops and rid them of destructive pests. That's the indication from Agricultural Research Service (ARS农业研究局) studies in which scientists pitted Muscodor against potato tuber(块茎) moths5, apple codling moths(苹果小卷蛾) and Tilletia fungi6 that cause bunt diseases in wheat. The scientists--at ARS laboratories in Aberdeen, Idaho; Wapato, Wash., and other locations--conducted separate studies of Muscodor. However, their goal was the same: to learn whether volatile7(不稳定的,挥发性的) organic compounds (VOCs) released by the fungus could replace or diminish(减少,变小) the use of synthetic8 pesticides9.
In field trials conducted since 2007, ARS plant pathologist(植物病理学家) Blair Goates found that treating wheat seed or the soil with a formulation of Muscodor and ground rye completely prevented common bunt under moderate disease conditions. Caused by the fungus T. tritici, common bunt reduces wheat yields and grain quality. Although chemical fungicide seed treatments have kept common bunt outbreaks to a minimum, alternative controls are worth exploring if the chemicals lose effectiveness or are discontinued, notes Goates, with the ARS Small Grains and Potato Germplasm Research Unit in Aberdeen. Results from this study were published in the Canadian Journal of Microbiology.
At the ARS Yakima Agricultural Research Laboratory in Wapato, entomologist(昆虫学者) Lerry Lacey and colleagues tested Muscodor against potato tuber moths, which damage potato leaves and tubers, and apple codling moths, which feed inside apples. In fumigation10 chamber11 tests, 85 to 91 percent of adult codling moths died when exposed to Muscodor fumes12, while 62 to 71 percent of larvae13(幼虫,幼体) died or failed to pupate(化蛹) . In apple storage tests, a 14-day exposure to Muscodor killed 100 percent of cocooned14(茧,乱囊) codling moth4 larvae, which are especially difficult to control.
Lacey and colleagues have also been testing Muscodor's effectiveness in biofumigating sealed cartons(纸板盒,箱数) of apples stored at various temperatures. The results have been encouraging so far, he reports, and there appears to be no adverse15 effect(不利影响,副作用) on the apples' color, firmness or other characteristics.