ABSTRACT
The relationship between damage by citrus leafminer, Phyllocnistis citrella Stainton, and 'Tahiti' lime yield were investigated in a 15-yr-old and a 5-yr-old lime orchard. Citrus leafminer population densities were controlled by insecticide applications of abamectin plus FC 435 oil, abamectin plus FC435 oil plus imidacloprid, and methomyl. The control was not treated. To ensure adequate citrus leafminer densities, adult citrus leafminer were periodically released in the experimental plots during fall and winter. For the 15-yr-old trees, the least amount of leaf area damage occurred in the abamectin plus FC 435 oil plus imidacloprid (1.9%) and the abamectin plus FC435 oil (2.3%) treatments compared with the control treatment (10-21%). In the 5-yr-old orchard, the least amount of leaf area damaged occurred in the abamectin plus FC 435 oil plus imidacloprid (0.4%) and the imidacloprid (0.1%) treatments compared with the control (20.85%). The percentage of leaf area damaged was linearly correlated with the average number of mines per leaf, average mine days, and cumulative mine days in both orchards. In both orchards, the percentage of leaf area damaged and cumulative mine days was linearly correlated with the number of fruit per tree and total fruit weight per tree. Calculating the economic injury levels indicated that 16-23% and 18-85% of leaf area damaged caused significant yield reductions in 15-yr-old and 5-yr-old trees, respectively.
Subject(s)
Citrus/growth & development , Insect Control , Moths , Animals , Imidazoles , Insect Control/economics , Insect Control/methods , Insecticides , Ivermectin/analogs & derivatives , Methomyl , Neonicotinoids , Nitro Compounds , Population DensityABSTRACT
In experiments involving the induction of squamous cell carcinoma in 1846 hairless mice that were maintained on a wide variety of diets, it was found that those diets with the least optimum balance of nutrients had the greatest inhibitory effect on growth of cancer. Rate of onset and severity of tumors was caused to vary over a 20-fold range by means of dietary balance alone. These experiments suggest that dietary variation in general and intentional malnutrition in particular should be given special attention in the control of existing cancer in humans.
