ISSN:
1365-3059
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
Notes:
Experiments were conducted in the Guadalquivir Valley of Andalucía, southern Spain, in 1986 and 1987, using field plots naturally infested with different inoculum densities of the defoliating and nondefoliating pathotypes of Verticillium dahliae to determine the influence of verticillium wilt epidemics on yield of cotton cultivar Coker 310. The total number of bolls, the number of open bolls, and seed cotton yield were related to the growth stage of plants at first appearance of foliar symptoms, and to inoculum density and virulence of the V. dahliae pathotype prevailing in the soil. For the three yield components, the greatest reduction was observed in plants showing symptoms before opening of first flowers (about 650 degree-days after sowing). Yield increased with delay in the development of foliar symptoms during the crop season, and the effect of the wilt epidemics on yield was small or nil for plants that developed symptoms after opening of the first bolls (1400–1500 degree-days after sowing). A multiple regression equation was derived that related yield reduction to the physiological time accumulated from the time of sowing until the appearance of foliar symptoms and to the rate of disease intensity increase over physiological time. This multiple point model explained about 70% of the variation in cotton yield loss due to verticillium wilt.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1046/j.1365-3059.1997.d01-221.x
