Submitted to: Journal of Nematology
Publication Type: Abstract Only
Publication Acceptance Date: 4/6/2010
Publication Date: 9/1/2010
Citation: Nyczepir, A.P., Meyer, S.L.F., Cook, J. 2010. Preplanting tall fescue grass for controlling Meloidogyne incognita in a young peach orchard. Journal of Nematology. 42(3):261. Interpretive Summary: Preplant fumigant nematicides have traditionally been used to control root-knot nematodes in peach in the southeastern United States. Preplant fumigant nematicides in combination with a nematode resistant rootstock are recommended for increased tree longevity and maximum protection against root-knot nematodes. However, in recent years growers have been faced with economic hardships which made it difficult to afford the costs associated with preplant fumigation and (or) not being able to get the land fumigated at the recommended time of year due to a conflict with managing other crops. Finding a nonchemical alternative to preplant chemical control of root-knot nematodes is warranted. Greenhouse and field studies were initiated to examine the susceptibility of tall fescue grass lines to the Southern root-knot nematode. Results indicate that all fescue lines tested were either poor or nonhosts for root-knot nematode. An initial test evaluating Max-Q for susceptibility to the Northern root-knot nematode indicated that Max-Q did not support nematode reproduction compared to the control treatment. The effect of 1- and 2 year tall fescue (cv. Max-Q) preplant groundcover rotations for the management of root-knot nematode was initiated in 2005 in a field experiment in central Georgia. In 2008, both fescue rotations suppressed nematode populations in the soil compared with 2 years of continuous peach These data provide useful insights into the potential use of tall fescue grass as an alternative to preplant chemical control of root-knot nematode prior to peach orchard establishment.
Technical Abstract: Preplant fumigant nematicides have traditionally been used to control Meloidogyne spp. in peach in the southeastern United States. The current preplant nematicides recommended for managing Meloidogyne spp. in peach include the soil fumigants, 1,3-dichloropropene and metam sodium. Because the economic hardships afflicting growers in recent years have made it difficult to economically afford these chemicals, finding an alternative nematode control is warranted. Greenhouse trials were initially conducted to evaluate the susceptibility of tall fescue grass (Festuca arundinacea = Schedonorus arundinaceus) lines with or without endophytes to M. incognita. Fescue lines evaluated included, i) Jesup EI (E+, wild-type endophyte present), ii) Jesup EF (E-, no endophyte present), and iii) Max-Q (E+, but non-ergot producing endophyte). Peach (susceptible Lovell rootstock) was included as the control. Nematode reproduction criteria were used in evaluating fescue susceptibility. Peach supported greater (P < 0.05) reproduction of M. incognita than all fescue lines. Differences in reproduction were not detected among the fescue lines and all fescue lines were either poor or nonhosts for M. incognita. Furthermore, the presence of the endophyte did not appear to affect nematode reproduction. In a separate greenhouse study, Max-Q did not support M. hapla reproduction compared to a tomato control. Additionally, investigation of the effect of 1- and 2 year tall fescue (cv. Max-Q) preplant groundcover rotations for the management of M. incognita was initiated in 2005 in a field experiment in central Georgia. In 2008, both fescue rotations suppressed (P < 0.05) soil population densities of M. incognita J2 compared with 2 years of continuous peach (root-knot nematode susceptible Halford rootstock reference control). No differences in suppression of M. incognita J2 population density were detected between the 1 and 2 years of fescue rotation. Therefore, a tall fescue rotation has potential as a nonchemical preplant strategy to manage M. incognita in peach orchards in the southeastern United States.