Nonfumigant alternatives to methyl bromide for management of nematodes, soil-borne disease, and weeds in production of snapdragon (Antirrhinum majus)

Abstract

Two field experiments were conducted in north Florida to examine effects of solarization and reduced-risk pesticides on weeds, nematodes, soil-borne diseases, and yield of snapdragon (Antirrhinum majus). Five treatments were replicated five times in a randomized complete block design: fumigation with 80:20 methyl bromide:chloropicrin, solarization, solarization + Kodiak® (product with Bacillus subtilis), solarization + Biophos™ (product with dipotassium phosphonate and dipotassium phosphate), and non-treated control. Methyl bromide was generally superior to treatments involving solarization, which in turn were superior to the control, for improving flower yield and managing weeds, nematodes, and mortality due to plant disease. In the second year, solarization was more effective than methyl bromide in reducing plant mortality; however, surviving plants were larger and more productive following methyl bromide. In the second year, Biophos™ + solarization was as effective as methyl bromide in improving plant height, but not yield. However, integrating solarization with Biophos™ did not provide benefits over solarization alone in terms of flower yield. In some cases, solarization alone provided results similar to methyl bromide for managing weeds, nematodes, and plant disease mortality.

Keywords:

• floriculture
• integrated pest management
• Meloidogyne incognita
• root-knot nematodes
• Pythium spp.
• solarization
• sustainable agriculture

Acknowledgement

This research was supported in part by USDA-CSREES Methyl Bromide Transitions Program grant no. 2006-51102-03566 entitled “Short-term methyl bromide alternatives for the Florida floriculture industry”, and by USDA, ARS Specific Cooperative Agreement no. 58-6618-6-207 entitled “Management of root-knot nematodes and other soilborne pests in floriculture production systems”. Mention of any trade names or products does not imply endorsement by the University of Florida or USDA. The authors thank Jeff Pack and Namgay Om for assistance in the field, John J. Frederick for technical assistance with nematode counting, Simon Poon for laboratory assistance, and Buck Nelson and the staff of PSREU for management of field plots.