Effects of nematicides on population of pratylenchus penetrans and growth of flue-cured tobacco

Abstract

Abstract Field studies were conducted on loamy sand at Tamscu farm, Delhi, Ontario, to compare the spring ridge application of Telone C17 at 73 and 101L/ha, Vorlex at 28 and 84L/ha, Vorlex CP at 50L/ha, and spring rotovated application of oxamyl at 2.24kg/ha respectively for the control of Pratylenchus penetrans (Cobb) Filip. and Stek., and for effects on the yield and quality of fluecured tobacco. Experiments were conducted on May 9 in an area that had been summer fallowed in previous year. Nematode densities of P. penetrans per kilogram of soil were lower than other treatments and controls with Telone C17 at 73 L/ha treated plots on May 24; with Vorlex at 28 L on June 7; Vorlex at 84 L on May 24 and on June 7; Vorlex CP on June 7, and with oxamyl on Sept. 6. The nematode population counts per gram dry weight of root were lower with Telone C17 at 73 L/ha on June 7, July 5, and at 101 L/ha on July 5; with Vorlex at 28 L/ha on June 7, July 5, and Sept. 6; with Vorlex at 84 L/ha on June 7, June 21, July 5 and Sept. 6, and with Vorlex CP at 50 L/ha on June 7, July 5 and Sept. 6 in the ridged soil. The population was lower with oxamyl on June 21, July 5, and Sept. 6 in the rotovated soils. There was no difference in the agronomic data on yield, indices of grade, crop and maturity, while tobacco plant height and dry weight in the ridged fanning were greater with treatments of Vorlex at 84 L and Vorlex CP at 50 L/ha. The ridged farming had greater yield of tobacco than rotovated farming. Vorlex was the most effective of all nematicides used in the experiment.