Tobacco Insect Control with Karate, 1989

Abstract

Abstract Experiments were conducted at the Virginia Polytechnic Institute and State University, Southern Piedmont Agricultural Experiment Station, Blackstone, VA. Tobacco was transplanted into a Chesterfield-Mayodan-Bourne sandy loam soil on 18 May. A randomized complete block design containing 4 replicates was utilized to evaluate 5 insecticide treatments and an untreated control. Experimental plots, 40 ft long (24 plants) and 8 ft wide (2 rows) were separated by single untreated border rows. Blocks were separated by vacant 5- or 12-ft alleys. The test site was treated with Telone II (15 gal/acre) and Mocap 6 EC (1 gal) on 21 Apr and 22 May, respectively, to control tobacco cyst nematodes. Insecticide treatments were applied with a COs-powered backpack sprayer that delivered 20 gal of finished spray/acre at 60 psi through 3, TX-10, hollow cone tips. Applications for Test 1 were made on 7 Jul. After the first test was completed, the tobacco stalks were cut back to ca. 6 inch of the soil surface and single suckers were allowed to grow from each stub. On 23 Aug the second test received the same treatments as the first. Prior to the first test, all plants in the 1st row of each plot were artificially infested with 3-5 d old THW larvae. Before the second test, 3-5 d old THW and TBW were used to infest each plant in the first and second rows, respectively, of each plot. TA on the 4 upper leaves at least 3 inch long were counted on 10 plants/plot at 3, 7 and 14 DAT in Test 1, and at 2, 8 and 14 DAT in Test 2. THW and TBW were counted on all plants in the first and second rows, respectively. TFB were counted on 5 plants/plot on those dates in Test 2. It rained 1.1, 0.05 and 1.05 inch at 7, 8 and 9 DAT, respectively, in Test 1. There was no rainfall during Test 2.