Effect of Length of Rotation on Losses from Black Shank in Flue‐Cured Tobacco Varieties¹

Abstract

Synopsis Five flue‐cured tobacco varieties were grown in rotations on a black shank‐infested soil. In the 1‐year rotation, losses from black shank increased rapidly in succeeding tobacco crops, while in the 3‐year rotation losses decreased. The difference in black shank losses between the 3‐ and 1‐year rotations was significant in 1956 and 1957. The black shank pathogen was not eliminated from the soil by a 3‐year rotation or a 4‐year period between tobacco crops.

Race distribution and distribution of sensitivities to mefenoxam among isolates of Phytophthora parasitica var. nicotianae in Guizhou province of China

“…In the absence of resistant flue-cured tobacco cultivars, crop rotation may provide some disease control. A three-year crop rotation of tobacco and corn resulted in less disease (Matthews et al, 1959). Other than metalaxyl/mefenoxam, recently several newly registered fungicides have been used extensively around the globe to control oomycete pathogens.…”