Author
Timper, Patricia - Patty | |
MINTON, N - RETIRED - USDA ARS | |
Johnson, Alva | |
BRENNEMAN, T - UNIVERSITY OF GEORGIA | |
CULBREATH, A - UNIVERSITY OF GEORGIA | |
BURTON, G - RETIRED - USDA ARS | |
BAKER, S - UNIVERSITY OF GEORGIA | |
GASCHO, G - UNIVERSITY OF GEORGIA |
Submitted to: Plant Disease
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 3/31/2001 Publication Date: 7/1/2001 Citation: Timper, P., Minton, N.A., Johnson, A.W., Brenneman, T.B., Culbreath, A.K., Burton, G.W., Baker, S.H., Gascho, G.J. 2001. Influence of cropping systems on stem rot (Sclerotium rolfsii), Meloidogyne arenaria and the nematode antagonist Pasteuria penetrans in peanut. Plant Disease. 85:767-772. Interpretive Summary: The effects of crop rotation and pesticide treatment were evaluated in a field experiment that was naturally-infested with the organism that causes southern stem rot of peanut, the peanut root-knot nematode, and a parasite of this nematode. The crop rotations were peanut (P) rotated either two years of cotton (Ct), corn (C), or bahiagrass (B). The pesticide treatments for the peanut crop were the insecticide/nematicide Temik, the fungicide Moncut, Temik plus Moncut, and an untreated control. Populations of the nematode were lower in peanut in the Ct-Ct-P than in P-P-P,C-C-P, or B-B-P plots; and tended to be lower in plots treated with Aldicarb. Abundance of the parasite was highest in the P-P-P plots, intermediate in the B-B-P rotations, lowest in all other rotations, and was unaffected by aldicarb. The high parasite densities in the P-P-P plots may have contributed to the uncharacteristically low nematode populations in this monoculture. Incidence of stem rot in peanut was lowest in treatments wit Moncut, intermediate in the control, and highest in treatments with Temik alone. The more rapid plant growth in the Temik-treated plots may have created a favorable environment for stem rot. Technical Abstract: The effect of crop rotation (main plots) and pesticide treatment (subplots) on stem rot (Sclerotium rolfsii), Meloidogyne arenaria, and the nematode antagonist Pasteuria penetrans was determined in a field experiment with four replications per treatment. The field site was naturally infested with all three organisms. Peanut (P) was rotated with either two years of cotton (Ct), corn (c), or bahiagrass (B). The pesticide treatments for th peanut crop were aldicarb (3.4 kg a.i./ha), flutolanil (1.7 kg a.i./ha), aldicarb + flutolanil, and a control without either pesticide. Populations of M. arenaria were lower in peanut in the Ct-Ct-P than in P-P-P, C-C-P, or B-B-P plots; and tended to be lower in plots treated with aldicarb. Abundance of P. penetrans endospores was highest in the P-P-P plots, intermediate in the B-B-P rotations, lowest in all other rotations, and was unaffected by aldicarb. The high endospore densities in the P-P-P plots may have contributed to the uncharacteristically low nematode populations in the monoculture. Incidence of stem rot in peanut was lowest in treatments with flutolanil, intermediate in the control, and highest in treatments with aldicarb alone. The greater canopy cover in aldicarb- treated plots may have created a conducive environment for S. rolfsii infection. |