Submitted to: Proceedings of International Research Conference on Methyl Bromide Alternatives
Publication Type: Proceedings
Publication Acceptance Date: November 7, 2000
Publication Date: N/A
Interpretive Summary: The root-lesion nematode, Pratylenchus vulnus, has been identified as an important pest of Prunus in California and other parts of the world. However, little is known about the economic importance of this nematode to the peach industry in the southeastern United States. Determining the host susceptibility of commercially available peach rootstocks to P. vulnus that are currently recommended for management of other nematode related disease problems in the Southeast must be investigated. Guardian, Lovell, and Nemaguard peach rootstocks were evaluated for their susceptibility and growth response to a root-lesion nematode isolated from peach in Georgia. Nematode reproduction and pathogenicity on all rootstocks were determined after 29 months in outdoor microplots. All rootstocks were rated as hosts to this root-lesion nematode. These data provide useful insights into the utilization of commercial peach rootstocks established in orchards infested with root-lesion nematode in the Southeast. Therefore, recommending Guardian as an alternative management strategy to chemical control of root-lesion nematode would not be feasible at this time.
Technical Abstract: Guardian, Lovell, and Nemaguard peach rootstocks were evaluated for their susceptibility and growth response to Pratylenchus vulnus (Georgia-isolate). Nematode reproduction and pathogenicity as related to rootstock were determined 29 months after inoculation in outdoor microplots (25.4-cm-d x 30.5-cm deep). The nematode reproduced on all rootstocks. A significantly greater number of nematodes per gram dry root weight were recovered from Guardian than from Nemaguard, but neither rootstock differed from Lovell. Nematodes per gram of dry root is a better measure of nematode reproduction than numbers of nematodes per 100 cc soil or total nematodes recovered from roots. Tree growth as measured by fresh shoot and root weights and trunk diameters was lower in trees grown in soil infested with P. vulnus than in uninoculated soil.