U.S. Department of Agriculture: Agricultural Research Service, Lincoln, Nebraska
Date of this Version
3-2017
Citation
ANNUAL REPORT OF THE BEAN IMPROVEMENT COOPERATIVE, No. 60, March 2017. Published by USDA.
Abstract
INTRODUCTION The black armyworm Spodoptera cosmioides (Walker, 1858) (Lepidoptera: Noctuidae), is widely distributed in South America, except for southern Argentina, Chile, and regions located to the west of the Andes in Peru (SILVAIN, LALANNE -CASSOU, 1997). In Brazil, this specie has occurred in several crops, including soybean, cotton and bean, causing injuries on leafs and pods that result in substantial losses in the plant yield (SPECHT et al., 2004).
Thus, Host-Plant Resistance becomes an alternative method as a strategy in the control of this pest, since resistance features expressed by some plants can cause changes in the behavior, and / or biology of phytophagous insects, or provide greater support capacity to their attack (BOIÇA JÚNIOR et al., 2013). Therefore, the aim of this study was to evaluate the development and fitness of S. cosmioides larvae fed on bean genotypes.
MATERIAL E METHODS Bean genotypes used were BRS Pérola, IAC Harmonia, BRS Supremo, BRS Talisman and IPR Campos Gerais. The leaves of the genotypes (treatments) were individualized into 9-cmdiameter Petri dishes lined with deionized water moistened filter paper. In each plate, a newly hatched larvae of S. cosmioides was released. Experiment was carried out under a completely randomized design with 30 replications. Data on larval stage duration, larval survival and larval weight of S. cosmioides were recorded. In addition, the larval performance of S. cosmioides was observed by calculating the Fitness Index (FI), adapted from Boregas et al. (2013), using the formula: FI = larval survival (%) × pupal biomass (mg) / larval development period (days) / 10.
Comments
U.S. government work.