Potato Aphid Control with Nematicides/Insecticides, 1985

Nine soil treatments applied for nematode control were evaluated for their effect on potato aphid (PA) populations on processing tomatoes. A commercial tomato field located near Woodland, CA was used for the tests. Treatments were replicated 4 times in a complete randomized block design and consisted of double-row beds, 1.5 m wide and 32.3 m long. Tomatoes were direct seed planted on 25 Mar ’85, thinned to approximately 2 plants/25.0 cm/row at the 5-leaf stage and were furrow irrigated. Soil type was a very fine sandy loam (Laugenour). Temik, Nemacur and Dasanit treatments were shanked 5.1 cm deep into the soil and 7.0-10.0 cm outside of seedline at planting. Telone was shanked 25.0 cm into the soil on 20 Feb. Vydate was shanked in like granulars, but under pressure and with a small amount of water at plant emergence (17 Apr) followed on 13 May with a second application. Soil-Prep was applied on 21 Feb by soaking the entire raised bed with 6.4 cm of water containing the treatment using 2 drip lines/bed spaced 33.0 cm apart with emitters every 30.0 cm. Proportion infested plants was determined by examining the second or third true leaf above the cotyledon for the presence of PA on 10 randomly selected plants/replicate/observation date.