| Abstrakt: |
Previous Texas High Plains research on the cotton plant's ability to compensate for early fruit loss indicated that 40-50% pre-flower square loss achieved through manual removal of pinhead squares could be fully compensated for lint yield and quality. Recent research also indicated that insect-induced early fruit loss could also be compensated, but at a much lower level than that for manual removal. However, the plant's ability to compensate insect-induced fruit loss may depend on soil moisture, other input variables, and overall plant vigor. The objective of this study was to quantify the compensatory ability of cotton to insect-induced fruit loss in a high input production system utilizing subsurface drip irrigation. Experiment consisted of four Lygus augmentation treatments [3 Lygus bugs per plant (3PP), 1 Lygus per plant (1PP), natural control or untreated control (UC), and spray control with no Lygus augmentation (SC)] to generate four levels of fruit loss during pre-flower and early flower stages, and all potential plant growth and reproductive parameters were measured. Preliminary results of the study suggested that the plant could compensate pre-flower square loss slightly better (25-30%) than the early flower fruit loss (20-25%) when environmental conditions were favorable. If conditions were not favorable, 25-30% of the fruit will be shed physiologically, therefore an insecticide intervention to save early squares may not be necessary. Consequently, it is important to consider plant compensation potential, input variables (fertility, moisture), and environmental stress while making insect management decisions. However, control costs and efforts to protect less than a 30% and 20% fruit shed during early squaring and during early flowering, respectively, may not be necessary under full irrigation production in the Texas High Plains region. [ABSTRACT FROM AUTHOR] |
