Author
Schneider, Sally | |
Trout, Thomas | |
Gerik, James | |
SHRESTHA, A. - UC KEARNEY AG CENTER | |
RODRIGUEZ-KABANA, R. - AUBURN UNIV. |
Submitted to: Proceedings of International Research Conference on Methyl Bromide Alternatives
Publication Type: Proceedings Publication Acceptance Date: 9/4/2005 Publication Date: 10/30/2005 Citation: Schneider, S.M., Trout, T.J., Gerik, J.S., Shrestha, A., Rodriguez-Kabana, R. 2005. Methyl bromide alternatives for perennial crop field nurseries. Proceedings of International Research Conference on Methyl Bromide Alternatives. October 31 - November 3, 2005 Proceedings, pp 41-1 - 41-4. Interpretive Summary: Certified nursery crops must be free of economically important plant parasitic nematodes, microscopic worms that attack plants. Methyl bromide is the most widely used soil treatment for meeting certification standards, as well as weed control, in perennial field nurseries. With the ban on import and manufacture of methyl bromide in effect since Jan. 1, 2005, growers need alternatives to methyl bromide. US nursery growers have obtained Critical Use Exemptions for nursery crops for 2005 and 2006. We found that using standard shank-injected fumigation methods with 1,3-dicholoropropene (1,3-D), 1,3-D + chloropicrin, and iodomethane + chloropicrin provided weed and nematode control similar to methyl bromide. Using drip-applied formulations of these same materials did not effectively control nematodes 24- and 36-inches deep in the deep alluvial loam soil. Microplots were used to evaluate experimental rates and combinations of sodium azide, furfural, metam sodium, acrolein, and propylene oxide. Weed and nematode control was promising with some rates and some combinations of these materials, but the nematode populations were too low to reach strong conclusions. Technical Abstract: Certified nursery crops must be free of economically important plant parasitic nematodes. Methyl bromide is the most widely used soil treatment for meeting certification standards in perennial field nurseries. With the ban on import and manufacture of methyl bromide imposed beginning Jan. 1, 2005, growers need alternatives to methyl bromide. US nursery growers have obtained Critical Use Exemptions for nursery crops for 2005 and 2006. An almond tree nursery trial was initiated in Sept. 2004. Shank-injected methyl bromide, Midas (67% iodomethane, 33% chloropicrin, 360 lb/acre), Telone II (1,3-dichloropropene, 31 gal./acre) and Telone C35 (61% 1,3-D, 35%chloropicrin, 47 gal/acre) provided good nematode control to a depth of 36 inches. Drip-applied formulations at the same rates effectively controlled nematodes to a depth of 6 inches, drip Midas and 1,3-D + chloropicrin provided nematode control to 12 inches, but none of the drip applications provided sufficient control at the 24 and 36 inch depth in the deep alluvial loam soil. All chemical treatments provided weed control comparable to methyl bromide 2 and 6 months after treatment. Germination of almond seed was comparable to methyl bromide in all chemical treatments except drip-applied Midas. Microplot trials were conducted to evaluate sodium azide, furfural, metam sodium, acrolein, and propylene oxide. Weed and nematode control was promising at some rates of these materials, but nematode populations were too low to reach strong conclusions. Additional evaluations are needed. |