Influência de cultivar e nível de infestação de Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) no rendimento do sorgo

Abstract

An experiment was conducted in the greenhouse to evaluate the effect of sorghum (Sorghum bicolor) cultivars and Spodoptera frugiperda (J. E. Smith) infestations, at different plant developmental stages, on sorghum yield. Second instar larvae of S. frugiperda were used to infest plants. Significant differences (P < 0,05) were found for the factors cultivar and stage of infestation for panicle (size and weight), grain (volume and weight) and 100 grain weight. No significant differences were observed for grain yield between damaged plant and the checks for the cvs. AG 3001 and CMSXS 375. However, the yield loss for the cv. BR 300 ranged from 11,6 to 21,7% for plants infested at 1st (15 days) and 4th stage (15 and 37 days), respectively.

Feeding preference of Spodoptera frugiperda on different sorghum genotypes

“…The S. frugiperda occurs more frequently in maize, which is more susceptible when compared to sorghum (CORTEZ, 1997) due to the insect's difficulty in feeding of sorghum. When the S. frugiperda feed, its maxillary palms and labratory gustatory receptors transmit information to the nervous system, which perceive the presence of chemical, physiological and / or morphological changes in the plant and transmit commands to the central nervous system of the insect, causing it to choose other plants to feed on (SMITH, 2005).…”