EFFECT OF SPIROTETRAMAT (MOVENTO®) ON HATCH, PENETRATION, AND REPRODUCTION OF ROTYLENCHULUS RENIFORMIS
Spirotetramat is a lipid biosynthesis inhibitor active against hemipteran insect pests and plant-parasitic nematodes such as Heterodera, Meloidogyne, Pratylenchus, and Tylenchulus. Reniform nematode (Rotylenchulus reniformis) has traits and behaviors that involve lipid biosynthesis; consequently, we wanted to know if spirotetramat could affect hatch, penetration, and reproduction of R. reniformis. To assess effects on hatch, R. reniformis eggs were exposed to Movento® solutions at 0, 50, 100, or 200 g a.i/ha and hatched juveniles counted up to 6 days later. Penetration on tomato (Solanum lycopersicum) roots and reproduction on pineapple (Ananas comosus) by R. reniformis as affected by spirotetramat at 0, 50, 100, or 200 g a.i/ha were also determined. Tomato and pineapple plants were treated with spirotetramat 14 or 28 days post-inoculation, respectively. Tomato roots were stained with acid fuchsin and checked for nematode penetration, or pineapple roots were shaken in sodium hypochlorite and eggs extracted. In insects, a secondary metabolite is the active moiety. In the hatching test, this secondary metabolite may not have been formed in the solution or may not have been mobile across the nematode eggshell, thus no effect was observed on nematode hatch. Penetration on tomato roots by R. reniformis was also not affected 14 days after spirotetramat application. However, in pineapple, reproduction of R. reniformis was suppressed by spirotetramat at 100 and 200 g a.i/ha compared to water control. Spirotetramat has the potential to control R. reniformis on crops.