High-pressure Liquid Injection of Isazofos for Management of Hoplolaimus galeatus and Tylenchorhynchus dubius Infesting Turfgrasses

Abstract

Three high-pressure liquid injection machines were used to inject isazofos into the root zone of turfgrass plots to evaluate its potential for control of Hoplolaimus galeatus and Tylenchorhynchus dubius. A Rogers root zone injector delivering isazofos at 2.3 kg a.i./ha through 30ordm; and 60ordm; spray tips at 5,000 psi (3.45 × 10[sup7] Pascals) significantly reduced nematode populations at 32 days after a single application and 33 days after a second application. In a second experiment with the Rogers injector at 2.3 kg a.i./ha, H. galeatus populations were significantly lower at 16 days after a single application and at 42 and 61 days after a second application with the 60ordm; spray angle tips. An Envirojet turfgrass injector used to inject isazofos at 1.15 kg a.i./ha and 2.88 kg a.i./ha at 3,000 psi (1.38 × 107 Pascals) significantly reduced nematode populations at 7 days after treatment at the low rate and at 63 days after treatment with both application rates. A Landpride material injector applying isazofos at 6.9 and 13.8 kg a.i./ha at 2,000 psi (1.38 × 10[sup7] Pascals) significantly reduced nematode populations at 7, 14, and 63 days after treatment at the high rate and at 63 days after the low-rate application. Although suppression of nematodes with isazofos was found, the degree of suppression is probably not enough to warrant recommendation of high-pressure delivery of isazofos for control of H. galeatus and T. dubius populations infesting turfgrasses. Key words: Agrostis canina, Agrostis palustris, annual bluegrass, control, creeping bentgrass, high-pressure liquid injection, Hoplolaimus galeatus, isazofos, Lolium perenne, nematicide, nematode, perennial ryegrass, Poa annua, turfgrass, Tylenchorhynchus dubius, velvet bentgrass.