36th International Carrot Conference Abstract

Evaluating nematicides for the control of soil-borne nematode pests on vegetable crops in Ontario.

D. Van Dyk, K. Jordan and M. R. McDonald.

Department of Plant Agriculture, University of Guelph, 50 Stone Road East, Guelph, ON N1G 2W1, Canada.

Recently 1,3-Dichloropropene and similar fumigants were removed from the market in Canada, so damage to carrots (Daucus carota L., subsp. sativus (Hoffm.) Arcang) caused by northern root-knot nematode (Meloidogyne hapla Chitwood) has become a constraint to production. In 2011, chloropicrin fumigants were registered for many crops, including carrots. In 2012, a field trial was conducted in the Grand Bend area of Ontario to evaluate the efficacy of this fumigant. Plots were fumigated in three 24” bed strips during the spring prior to planting carrot cultivars Envy and Olympus. The treatments were PicPlus (cholorpicrin 86%) at 58, 67, and 96 kg a.i./ha, Vydate (oxamyl 24%) at 0.48 L a.i./ha, and an untreated check. Assessments of percent damage caused by root knot nematodes and violet root rot (Rhizoctonia crocorum) were conducted mid-season and at final harvest. At mid-season carrots treated with PicPlus at 96 kg a.i./ha had 13% total damage, compared to 32% in the untreated check. At harvest, PicPlus at 58, 67, and 96 kg a.i./ha had 83, 86, and 75% marketable carrots, respectively, significantly higher than carrots treated with Vydate (47% marketable carrots). Chloropicrin products provided acceptable control of northern root-knot nematode damage on carrot in muck soils. In January 2013 a greenhouse trial was conducted to evaluate additional nematicides. Mineral soil was inoculated with Meloidogyne hapla and treated with Busan 1236 (metam sodium 42.5%) at 210 L a.i./ha, Dazitol (capsaicin 0.42%, allyl isothiocyanate 3.7%) at 59 L a.i./ha, MustGrow (oriental mustard seed meal 100%) at 840 kg a.i./ha, Movento (spirotetramat 240 g/L) at 685 g a.i./ha, Agri-Mek (abamectin 2%) at 2 L a.i./ha, and MCW-2 (fluensulfone 15%) at 4 kg a.i./ha. An inoculated and non-inoculated check was also included. Tomatoes cv. Roma were transplanted into conetainers in a randomized complete block design. Tomatoes treated with Dazitol were similar to the grower standard Busan in gall rating (0.8 to 0), and dry shoot weight (13.0g to 16.3g) at harvest. MustGrow had significantly higher SPAD green rating (27.9 to 22.4), dry root weight (7.4g to 4.6g), dry shoot weight (16.7g to 12.9g) and lower gall rating (0.5 to 2.5) than the inoculated check. MCW-2 exhibited phytotoxicity at the rates applied in this study. Treatments of foliar applied Movento and an Agri-Mek drench did not differ significantly from the inoculated and non-inoculated checks. The nematicides Dazitol and MustGrow showed acceptable control compared to the grower standard fumigant in this initial greenhouse study.

Last updated Thursday, 25-Jul-2013 11:52:44 CDT