| Popis: |
A field evaluation of insecticides for Heliothis spp. control on cotton was conducted at the Plant Breeding Unit of Auburn University, Tallassee, AL. Cotton was planted 23 Apr in 40-inch rows. Six treatments were replicated 4 times in a randomized complete block design. Plots were nine rows × 75 ft with 25-ft alleys between blocks. Insecticides were applied with a high-clearance sprayer at a rate of 9.3 gal spray/acre (3.4 mph, 50 psi, 2 Teejet™ TX6 nozzles/row). Foliar applications were made for Heliothis spp. control on 2, 6, 19, and 23 Aug. Plots were sprayed with Guthion as needed for weevil control. Terminal damage and numbers oflarvae were estimated by examining 25 randomly selected plant terminals from the middle 3 rows of each plot on 5, 9, 22 and 27 Aug. Yield data were taken by mechanically picking 2 of the 3 middle rows of each plot. |
