Evaluation of Foliar Applied Insecticide for Spwf Control, 1991:

A small plot field study was conducted in a commercial cotton field near Monte Alto, TX, to evaluate control efficacy of various insecticides and insecticide combinations against the SPWF. Experimental plots measured 1 row (40 inches) by 25 ft, with 1 buffer row between plots. Each treatment was replicated 4 times in a RCB design. Treatments were applied 28 May and 3 and 10 Jun with a CO2 pressurized backpack sprayer using 3, lOx nozzles per row (1 overtop, 2 on drops) in a total volume of 50 gal/acre (at 50 psi). Adult SPWF were sampled at 24 h after each application by counting the number of adults on the third fully expanded leaf from the top on 3 plants per plot. All other stages were sampled by removing designated leaves (1st sample–4th true leaf; 2nd sample–5th leaf from terminal; 3rd sample–6th leaf from terminal) from 3 plants per plot and transporting them to the laboratory for examination. Each leaf was placed under an index card containing 5 hole punches (0.25 inch diam each) and examined under magnification. All stages were counted and totaled for each leaf. Analyses for all SPWF stages were performed on the number collected per plot (total for 3 leaves). Counts for eggs and immatures were transformed using the Log transformation of data +1 because of unequal variances. On the last sample date, plots were given a visual rating on a 5 point scale of 1 to 3 with 0.5 increments based on the relative abundance of honeydew and sooty mold (1 least amount–3 heavy sooty mold).