Abstract
Three field trials were conducted to determine the effect of various levels of resistance of South African sorghum hybrids on follow-up generations of Busseola fusca Fuller (Lepidoptera: Noctuidae) and Chilo partellus (Swinhoe) (Lepidoptera: Pyralidae). In one trial, plants were artificially infested with B. fusca larvae while the other trials were subjected to natural infestation of C. partellus. The number of damaged internodes and moth exit holes per stem were used to calculate a relative survival index which estimates the survival of larvae to the adult stage. A moth production index was calculated to estimate the role of a hybrid in area-wide suppression of stemborer populations. In the B. fusca trial, resistant and susceptible experimental hybrids produced 40 000 and 113 000 moths per hectare respectively, compared to 80 000 and 83 000 moths per hectare produced by the commercial hybrids. Larval damage to whorl leaves, assessed on a 1 to 9 scale, indicated leaf-feeding resistance of commercial hybrids to B. fusca ranging from susceptible to intermediate. Yield losses suffered by the hybrids in the B. fusca trial were greater than that suffered by a susceptible experimental hybrid, indicating susceptibility of South African hybrids to B. fusca. The evaluation of sorghum varieties for their potential to reduce stemborer populations should indicate their usefulness in integrated pest management systems.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
