Submitted to: National Cotton Council Beltwide Cotton Conference
Publication Type: Proceedings
Publication Acceptance Date: January 8, 2003
Publication Date: January 8, 2003
Technical Abstract: Beauveria bassiana is an entomopathogenic fungus that was found infecting the Western tarnished plant bug (WTPB), Lygus hesperus in California cotton producing counties. WTPB is one of the most important pests of cotton and can cause annual losses exceeding $30 million. A San Joaquin Valley wide survey revealed that B. bassiana was present in almost every sample of WTPB collected throughout the year. Infection levels were generally 5-10% but some samples of WTPB were 50% or more infected with the fungus. A detailed study of 9 selected alfalfa fields revealed the presence of B. bassiana in every field. In one year, prevalence of B. bassiana was related to the age of production of the alfalfa fields sampled suggesting a buildup of inoculum with time. Similarly, the percentage infection was related to the WTPB population size. Percentage infection within a field was also related to time, i.e. prevalence of fungus increased throughout the year.