Submitted to: Nematropica
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/21/2006
Publication Date: 6/1/2007
Citation: Starr, J., Ong, K., Huddleston, M., Handoo, Z.A. 2007. Control of meloidogyne marylandi on bermuda grass. Nematropica. 37(1):43-49. Interpretive Summary: Plant-parasitic nematodes are microscopic worms that live in the soil and cause an estimated ten-billion-dollar crop loss in the United States each year. Root-knot nematodes are the most important group of nematodes and damage many kinds of plants. In Texas, one specific root-knot nematode causes poor growth and unsightly appearance of many turfgrasses, including Bermudagrass putting greens. Unfortunately, the development of means to safely and effectively reduce this damage remains a major problem. In this study, scientists from Texas A & M University and the Texas Department of Agriculture compared the efficacy of two chemical nematicides and a commonly used biological control fungus in reducing the damage caused by root-knot nematodes to golf courses. An ARS scientist primarily provided expertise in identifying the species of nematodes present in the turf and soil. The results indicated that effective reduction of nematode numbers and improvement of turf color and quality were provided by only one chemical nematicide. This research is significant because it has revealed one means of controlling root-knot nematode damage on golf courses, and also because it indicates that a different biological control agent must be pursued in order to find a safer means of nematode control. This research will be used by scientists and extension personnel who are developing new methods for safely controlling nematode-induced turfgrass losses.
Technical Abstract: Meloidogyne marylandi is widely distributed on turf in Texas and is frequently associated with poor turf appearance and growth. Suppression of population densities of M. marylandi on established Bermudagrass through application of a new formulation of 1,3-dichloropropene (Curfew), fenamiphos (Nemacur), or the biological agent Paecilomyces lilacinus (MeloCon WG) was tested in separate experiments. Application of the fumigant 1,3-dichloropropene effectively suppressed nematode population densities for 10 weeks and improved turf color (P = 0.8) and quality (P = 0.14). Neither P. lilacinus nor fenamiphos effectively suppressed nematode population densities or improved turf appearance. Fenamiphos did reduce root galling (P = 0.05) in one of two experiments. Juveniles of M. marylandi encumbered with Pasteuria spp. endospores were observed during these studies, and the efficacy of this biological control agent in established turf needs to be investigated.