Influence of Nutrition During Conidiation of<i>Colletotrichum truncatum</i>on Conidial Germination and Efficacy in Inciting Disease in<i>Sesbania exaltata</i>

Abstract

Schisler. D. A.. Jackson. M. A.. and Bothasl, R. J. 1991. Influence of nutrilion during conidiation of Colletotrichum truncatum on conidial germination and efficacy in inciting disease in Sesbania exaltata. Phytopathology 81 :587-590. - Conidia of CollelOtrichum truncatum (NRRL 13737) were produced in semidefined. liquid media, with total carbon concentrations of 4 gl L and carbon/nitrogen ratios of 80:1, 30:1. and 1O:1. Conidia produced in 10: I medium were longer and thinner than conidia from 30: I and 80: I media, and a higher proportion contained two, rather than one, nuclei per conidium. After either 6 or 12 h on cellophane membranes, a greater proportion of conidia produced in the 10: I medium had germinated compared with conidia from 30: I and 80: I media. Germination on attached leaves of Sesbania exaltata was greatest with conidia from 10: I medium when assayed after either 6 or 24 h. Equality of variance Additionalkeywords: bioherbicide, hemp sesbania, nuclear number, phylloplane, sporulation, weed. Hemp sesbania (Sesbania exaltata (Raf.) Rydb. ex A. W. Hill) is a weed of increasing importance in soybean. cotton, and rice crops, especially throughout the Coastal Plain and Piedmont regions of the southeastern United States (5). Colletotrichum truncatum (Schwein.) Andrus and W. D. Moore has potential