Yield Response and Efficacy of Penncap-M on Chinese Broccoli, 1984

Abstract

Abstract Broccoli yield, population estimates and feeding damage of cruciferous pests were used as indicators to determine the efficacy of Penncap-M. There was a 3-ft row spacing, 1.5 ft between plants, and 3 ft alley spacing between replicates. Treatments were arranged in a randomized block design with 4 replicates. Seedlings were transplanted on 31 Jul, following incorporation of 3 lb 10-10-10 fertilizer/100 sq ft and 10 lb lime/100 sq ft into a tilled plot and fumigation with bromomethane (1 lb/100 sq ft). A compressed air sprayer, with Teejet 8003 Fan type nozzles (one for the first application and 2, with a boom spacing of 30 inches, for the second and third applications) were used to deliver a foliar broadcast spray. Applications were made on 8, 15 Aug, and 5 Sep, coinciding with the seedling, post-seedling and mature plant growth stages. On 2 Aug it was necessary to treat all plants with Lannate to reduce a flea beetle population which would have caused high seedling mortality if left uncontrolled. Yield data were collected on 20 Sep bv weighing whole plants. Adult flea beetle populations on whole plants were assessed on 15 Aug by using the following rating index: 0 = 0 beetles, 1 = 1-10 beetles, 2 = 11-20 beetles, 3 = 21-30 beetles, 4 = 31-40 beetles, 5 = 41-50 beetles, 6 = 50+ beetles. Flea beetle feeding damage was also evaluated on 8 Aug by counting the number of feeding scars in a 1 cm2 area at the center of 1 randomly chosen leaf per plant. At the time of harvest (20 Sep) all imported cabbageworm and cabbage looper larvae on 5 randomly chosen plants per replicate were counted.