U.S. Department of Agriculture: Agricultural Research Service, Lincoln, Nebraska
Document Type
Article
Date of this Version
3-2017
Citation
ANNUAL REPORT OF THE BEAN IMPROVEMENT COOPERATIVE, No. 60, March 2017. Published by USDA.
Abstract
INTRODUCTION: The common bean (Phaseolus vulgaris L.) crop is affected by more than 200 diseases, capable to narrow the production and decrease the product quality physiological, nutritional and commercial, including anthracnose. The bean anthracnose, caused by the fungus Colletotrichum lindemuthianum (Sacc. & Magnus), is one of the most serious bean diseases, affecting susceptible cultivars worldwide (Bianchini et al., 1989). Potassium has a big relation with the incidence reduction and diseases severity in plants, acting in the inoculum potential reduction (Huber and Arny, 1985). Thus, the research objective was evaluating the severity and the bean anthracnose control under different levels of potassium.
MATERIALS AND METHODS: The experiment was conducted in greenhouse with 5 liter pots in the Imperatriz city, in the Maranhão state, Brazil. Three common bean genotypes were used, being the Pérola cultivar (susceptible to anthracnose), BRS Estilo cultivar (moderately resistant to anthracnose) and BRS Madrepérola cultivar (resistant to anthracnose), in a completely randomized design with five treatments (0, 80, 120, 140 And 180 kg.ha-1 as potassium chloride) and 4 replicates. The inoculation was done with a manual sprayer at the end V4 stage at 35 days after emergence, with a 1.2 x 106 conidia.mL-1 inoculum suspension. Severity assessments were made at 9 and 15 days after inoculation (DAI) according to the descriptive diagram scale proposed by Tamayo (1995), which ranges from 1 to 9 and the closer to 1 the lower the severity. For the analysis, was used the statistical program GENES (Cruz, 2013).
Comments
U.S. government work.