Abstract
Horticultural mineral oil (HMO) is an inexpensive, environmentally safe pest management alternative, and acceptable in some cases for products labeled for organic production. However, there has been insufficient information on efficacy and direct impact to vegetable crops, including tomatoes (Lycopersicum esculentum Mill.) and peppers Capsicum annuum L. under commercial conditions in south Florida. We conducted a series of field trials in Immokalee on pepper and tomato during two fall seasons and one spring season. Highly refined HMOs were tank mixed with fungicides, insecticides or sprayed alone at rates ranging from 0.5% to 2% at weekly intervals throughout the crop cycle. Pest populations significantly reduced in response to these sprays included silverleaf whitefly (Bemisia argentifolii Bellows and Perring), Broadmite (Polyphagotarsonemus latus Banks), green peach aphid (Myzus persicae Sulzer), and surprisingly, southern armyworm (Spodoptera eridania Stoll), and pepper weevil (Anthonomus eugenii Cano). It is not certain whether these effects were due to mortality, repellency or a combination of both. Some phytotoxicity and increased bacterial spot were observed with higher rates of oil on fall tomatoes, especially early in the fall season during hot weather. Nevertheless, HMO appears to be a useful and as yet under-exploited pest management tool for vegetable growers.
