Author
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Burelle, Nancy |
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Submitted to: Proceedings of Methyl Bromide Alternatives Conference
Publication Type: Proceedings Publication Acceptance Date: 8/31/2007 Publication Date: 10/1/2007 Citation: Burelle, N.K. 2007. Multiguard: Effects on nematode populations and galling on tomato and pepper. Proceedings of Methyl Bromide Alternatives Conference. 118:1-3. Interpretive Summary: Technical Abstract: Multiguard® Protect, a commercial formulation of furfural (2-furancarboxaldehyde), was evaluated in a series of greenhouse trials over three seasons for effects on plant growth, nematode populations in roots and soil, and galling caused by Meloidogyne incognita. ‘Tiny Tim’ tomato (Lycopersinon esculentum) and ‘Capistrano’ bell pepper (Capsicum annuum) were transplanted into pots containing field soil naturally infested with Meloidogyne incognita, as well as other pathogenic and microbivorous nematodes, and soil microorganisms. In the first set of trials, Multiguard treatments were applied as soil drenches at rates equivalent to: 1) 452 kg/ha, 7 days preplant; 2) 452 kg/ha, 7 days preplant + 28 kg/ha, 2 weeks post-plant; 3) 85 kg/ha, 7 days preplant; 4) 85 kg/ha, 7 days preplant + 28 kg/ha, 2 weeks post-plant; and 5) 28 kg/ha, 2 weeks post-plant. The experiments were performed twice, once in fall 2005 and repeated in winter 2006. In the second set of trials, performed in fall 2006, Multiguard treatments were: 1) 28 kg/ha, 2 days preplant; 2) 85 kg/ha 7, days preplant; and 3) 452 kg/ha 7, days preplant. An untreated control was included in all experiments. In the first set of trials, under warm fall conditions and high root-knot nematode pressure, high rates of Multiguard increased root-knot nematode populations in both roots and soil in both tomato and pepper compared to the untreated controls, and lower rates of Multiguard. However, even with significantly increased numbers of nematodes in roots and soil, galling was significantly reduced on tomato at the 452 kg/ha rate. Under cool conditions and low soil nematode numbers in the winter trials, the low rates of Multiguard increased root-knot nematode populations in tomato and pepper roots, similar to the effect with the higher rates in the fall trial. As in the fall trials, regardless of the number of root-knot nematodes isolated from roots or soil, the two 452 kg/ha preplant Multiguard treatments significantly reduced galling on tomato. In the second set of trials, increasing rates of Multiguard reduced root-knot nematode juveniles in tomato roots. Only the highest preplant rate reduced juveniles in soil of tomato. Gall ratings on tomato reflected the treatment effects on soil nematodes, with the highest rate of Multiguard reducing galling on tomato. However, an increase in galling on tomato occurred with the lowest rate of Multiguard. Multiguard affects parasitic nematodes differently than beneficial microbivorous nematodes, especially those isolated from roots. This effect varies depending on the host plant and rate of treatment, and may be indicative of less detrimental, or stimulating influences on soil microoganisms, on which microbivorous nematodes feed. At high rates, there are indications that Multiguard has an effect on either the host plant or the nematode that inhibits gall formation in tomato. Regardless of the effects of Multiguard on nematode and microbial ecology, high rates of Multiguard effectively managed galling caused by M. incognita on tomato, while lower rates and post-plant applications were not effective, or did not increase levels of control over the high rates applied alone. |
