Progress 08/01/11 to 09/30/12
Outputs
OUTPUTS: 1) Through a laboratory rearing experiment we determined that BMSB require fruits to complete development when restricted to a single woody plant: Cornus alternafolia: Three diet treatments were established: we fed 1st and 2nd instar nymphs either water alone, leaves alone, or fruits alone. This was repeated starting from filed collected 3rd and 4rth instar nymphs and again starting with stink bugs that had already reached maturity. Only treatments receiving fruits alone developed normally to reached maturity or, in the case of adults, live throughout the experiment. We conclude from this study that BMSB is an obligate frugivore as opposed to a folivore that can include fruits in their diet. This explains it's extraordinary host range, as fruits are not defended chemically the way leaves are and no specialized adaptations need to be in place in order to exploit evolutionarily novel plants. The next question is whether there are particular species of plants, such as Paulownia tomentosa with leaves nutritious enough to bring BMSB through to maturity in the absence of fruits. 2). Community Garden -Addresses Objective 1: Establish biology & phenology of BMSB in specialty crops Various vegetables in the University of Delaware Community Garden in Newark, DE were surveyed from mid- June through late August were sampled to determine which vegetable crops are preferred, the severity of damage and the impact on marketability. Sampling occurred once a week. The types of plants surveyed included zucchini squash, yellow squash, Cherokee purple tomatoes, Mortgage lifter tomatoes, tomatillos, okra, eggplant, white & yellow onions, Lemon basil, Sweet basil, California Wonder bell peppers, Golden California Wonder bell peppers, Jalapeno peppers, Anaheim peppers, and Hungarian Wax peppers. The number of nymphs, adults, and egg masses of Brown Marmorated, Brown, Green, and other stink bugs were recorded using a 5 minutes count for each crop. 3). Sweet Corn Projects - Newark Research Farm - Addresses Objective 2: Develop Monitoring & Management tools : An insecticide trial evaluating labeled and non-labeled insecticides was established on the University of Delaware's Research farm in Newark, DE. Nine treatments were replicated four times in a randomized complete block design. Plots were sampled starting at late whorl to determine when the first application should be applied. Unfortunately, BMSB populations were virtually non-existent until the end of July when plants were in the brown silk stage. A pre-treatments count was done on August first by counting number of Brown Marmorated Stink Bugs (BMSB) adults and nymphs observed during a two minute search time per treatment. Plots were harvested on August 6th and the number of clean, and BMSB damaged ears were recorded for each treatment. PARTICIPANTS: Douglas W. Tallamy is Professor and Chair in the department of Entomology and Wildlife Ecology at the University of Delaware. Joanne Whalen is Extension specialist (IPM ag crops) in the department of Entomology and Wildlife Ecology at the University of Delaware and Brian Kunkel is Extension Specialist (IPM Ornamentals) in the department of Entomology at the University of Delaware. An undergraduate (Jonathan Baker) and a graduate student (William Cissell) assisted with field studies. TARGET AUDIENCES: Target audiences include growers of corn, soybeans, peppers, green beans, tomatoes, eggplant, grapes, and apples, as well as homeowners who experience overwintering populations of BMSB. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
Our surveys and laboratory projects largely addressed the need to establish the biology and phenology of BMSB in speciality crops. In sweet corn our surveys suggest that when infestations occur from silk emergence through pollination, aborted kernels may result. When infestations occur during the blister and milk stages, kernel abortion is less of a concern, however, BMSB are capable of causing a significant number of discolored and collapsed kernels which may be problematic for the marketability of fresh market and processing sweet corn ears. Our laboratory experiments suggest that all fruiting plants, including important crops like corn and soybeans, regardless of their geographic origin in relation to Asian populations of BMSB, support growth and development in BMSB, Foliar resources alone appear to be inadequate for development except in isolated special cases. This was the first year of this project and no publications have resulted as yet.
Publications
- No publications reported this period
|