|The effect of spirotetramat (Movento®) against reniform nematode, Rotylenchulus reniformis, on pineapple, Ananas comosus.|
P. WAISEN (1), B. Sipes (2). (1) firstname.lastname@example.org, Honolulu, HI, U.S.A.; (2) Univ of Hawaii At Manoa, Honolulu, HI, U.S.A.
Reniform nematode, <i>Rotylenchulus reniformis</i> is an economically important plant-parasitic nematode of pineapple. This pathogen can reduce pineapple marketable yield by 26.8-50%. Lack of host resistance in pineapple raises a need for nematode management. Spirotetramat is a group 23 insecticide, a lipid biosynthesis inhibitor with ambimobile translocation. Lipids play a significant physiological role in embryogenesis and molting of plant-parasitic nematodes therefore inhibition of lipid biosynthesis may provide a critical management tool. The objective of this study was to determine if spirotetramat is active against reniform nematode. Greenhouse bioassays were conducted where pineapple crowns were planted in steam-sterilized soil in 20-cm-d biodegradable pots. Approximately 3,000 <i>R. reniformis</i> eggs were inoculated onto 4-month-old plants. Four levels (0, 88, 100 and 175 g a.i/ha) of spirotetramat were applied 1 month post inoculation. Plants were harvested 6 months later for shoot and root weights, and a 250 cm3 soil sample collected. Data were normalized by log10 transformation and subjected to analysis of variance. The maximum nematode reduction was 64% at 88 g a.i. spirotetramat/ha rate with a corresponding reduction in dry root weight of 14.4% and an increase in shoot weight of 1.4% compared to the water treatment control. The 88 g a.i. spirotetramat/ha rate gave promising reductions in nematode numbers while promoting plant growth.