The Status of Trichoderma aggressivum, the Causal Agent of Green Mold, in the United States as Determined in Response to 2010-2011 Quarterly Surveys

摘要

In response to the loss of the label for the use of Topsin M 70 WP (thiophanate-methyl) to control Trichoderma aggressivum, the causal agent of green mold, The Pennsylvania State University and the American Mushroom Institute initiated an online quarterly survey to assess the severity of Green Mold in the United States mushroom industry. The survey was initiated in the spring of 2010 and was sent on a quarterly basis to Agaricus bisporus growers across the US. Survey results demonstrate continued disease pressure in the US industry from Trichoderma aggressivum. The average grower response rate over the two years was approximately 45%, representing a large percentage of the mushroom farms in the US. In the most recent survey, 82% of the growers reported having Trichoderma green mold on their farm with 42% of the respondents indicating that disease pressures are at least a moderate threat to profitability. Disease severity will be correlated with chemical usage (spawn treatment, supplement treatment, drenching) as well as farm size and fly pressure. The results of this survey can be used to determine the economic impact that Trichoderma aggresivum is having on US mushroom production on a square meter basis.