Submitted to: Silverleaf Whitefly: 1997 Supplement to the Five Year National Research and
Publication Type: Abstract Only
Publication Acceptance Date: 8/1/1997
Publication Date: N/A
Technical Abstract: Honeydew contamination of cotton lint by whiteflies is a major concern at textile mills and is well documented. We determined relationship between frequency of insecticide applications triggered by thresholds of 5, 10, 15, and 25 adult whiteflies/leaf and honeydew production on cotton. On 4 dates lint was collected and analyzed for sugars using high performance liquid chromatography (HPLC). Whitefly densities and honeydew production were bot affected by frequency of insecticide applications. Densities of adults were generally higher in control plots, plots treated at 25 adults, and untreated plots than in plots treated at 5, 10, and 15 adults. Numbers of honeydew drops per square centimeter were higher in control, 25 adult, and untreated plots than in 5, 10, and 15 adult plots. Honeydew production was low throughout the season when spraying was initiated at 5 adults/leaf, but was not significantly different than when spraying occurred at 10 or 15 adults later in the season. Trehalulose was more abundant on lint collecte from control, 25 adult, and untreated plots than in 5, 10, and 15 adult plots. Honeydew drop densities were unexpectedly low in control and untreated plots on some later dates, especially on papers on bottom bolls. Control and untreated plants had fewer leaves than other plant during these times, suggesting leaf loss and plant level may account for some variability in honeydew production during late season.