Evaluation of pesticides for management of thrips and tomato spotted wilt in dryland peanut, 2018

摘要

'TUFRunner 511' peanuts were planted at Edisto Research and Education Center in Blackville, SC on 26 Apr, at a rate of 5.5 seed/ft and depth of 2-in under dryland conditions. Soil type was a Barnwell sandy loam. Rotation history was cotton for the previous two years. Plots were four 40-foot single rows on 38 in. centers with treatments replicated four times and applied according to a randomized complete block design. Standard practices were used to manage tillage, weeds, fungal diseases and nutrition. Admire Pro and Velum Total were applied with a D2 orifice set to deliver 8.7 gal/A at 32 psi in-furrow. Thimet was applied with a SmartBox calibrated to deliver 4.7 lb/A in-furrow. Orthene was applied using two DG8002 nozzles/row (19-in spacing) delivering 15 gal/A on 8 May (11 days after planting [DAP]) for at-crack applications and 18 May (21 DAP). Thrips damage was rated 13 Jun (48 DAP) using a 0 to 10 scale where 0 = no injury and 10 = dead plants. Phytotoxicity was also rated 13 Jun using a visual percentage scale, based on severity. Tomato spotted wilt stunting was rated by visually estimating the % of row exhibiting stunting symptoms of the disease (based on loci counts per row where 1 locus was < 1 ft of consecutive tomato spotted wilt stunted plants) on 23 Aug (119 DAP). Ratings of % of row exhibiting symptoms or signs of stem rot (based on loci counts per row where 1 locus was < 1 ft of consecutive stem rot damaged plants or signs per row) were taken 21 Sep. The trial was dug and invertedon 21 Sep and harvested 25 Sep (moisture adjusted to 10%). SAS 9.4 PROC GLIMMIX was used to determine effects of treatments, with mean separations compared according to Fisher's Protected LSD at a = 0.05. Yield data was modeled according to a negative binomial distribution. Average monthly temperatures for the growing season are as follows: 61.3°F (Apr), 74°F (May), 80.1°F (Jun), 80.4°F (Jul), 79.9°F (Aug), and 79.6°F (Sep).