Organic Mulch Increases Insect Herbivory by the Flea Beetle Species Disonycha glabrata on Amaranthus spp.

摘要

Amaranth ( spp.) is an increasingly high-valued niche vegetable crop among small organic growers in North Carolina, due to its increasing demand among diverse immigrant groups. Production is however hampered by insect pests such as the flea beetle (FB), (Coleoptera: Chrysomelidae), that cause significant yield reduction. Chemical insecticides are generally applied for pest control despite their known risks to health and the environment. Integrated pest management (IPM), which is a cost effective and environmentally friendly approach is still under-exploited in vegetable production by small growers. We studied IPM approaches, suitable for organic production of amaranth by screening nine amaranth varieties for resistance to the flea beetle (FB), . , grown with, and without, mulch. population was 60% higher in plots with mulch compared to plots without. The amaranth varieties and recorded the lowest and the highest population commensurate with low, and high leaf damage, respectively. Conversely, leaf yields in the mulched plots were 50% less than recorded in the zero-mulch counterpart, with variety recording the lowest. These findings will serve as building blocks for a sustainable pest management plan that is appropriate for organic production of spp. in North Carolina.