Bamboo Spider Mite Control With Foliar Applied Acaricides
Bamboo spider mites, Stigmaeopsis celarius Banks (=Schizotetranychus celarius) live in protected web nests and are difficult to control. Current recommendations are outdated and do not reflect the new acaricide chemistries. Nine acaricides were evaluated for bamboo spider mite control. Bioassays were performed with a Precision Spray Tower. Acaricides were applied at 15 psi in 1 ml of an aqueous suspension on to 0.5 inch long sections of bamboo leaves, Phyllostachys nigra inverted on water moistened cotton wool pads placed in Petri dishes. Spider mites were scored as alive or dead based on the presence/absence of motile live stages at 1, 2 and 3 days posttreatment. Replicated bioassays were performed on 23, 28 and 30 September 2004. Data for corresponding replications for the trial dates were from 25 leaf arenas per treatment.
Talstar (bifenthrin) provided complete control of the heavily webbed bamboo spider mite colonies after 24 hours. Metasystox-R (oxydemeton-methyl), Tame (fenpropathrin), Sanmite (pyridaben) and Mesa (milbemectin) provided comparable results with Talstar at 2 and 3 days posttreatment. The selective contact miticides Avid (abamectin), Floramite (bifenazate) and Kanemite (acequinocyl) performed poorly against the bamboo spider mite after 3 days. Specialty bamboo growers require quick knockdown of incipient bamboo spider mite colonies that can rapidly construct dense web nests reducing pesticide contact, making conventional control methods difficult.
Table 1. Bamboo spider mite bioassay on Phyllostachys nigra foliage.
|Avid 0.15EC||118 ml||0.005||15c||30b||44b|
|Floramite SC||113 g||0.25||15c||15bc||23bc|
|Kanemite 15EC||917 ml||0.3||11c||15bc||26bc|
|Mesa EC||946 ml||0.02||60b||78a||78a|
|Sanmite 75WP||113 g||0.2||84ab||96a||100a|
|Talstar F||592 ml||0.1||100a|
|Tame 2.4EC||473 ml||0.3||89a||100a|
|Means within columns followed by the same letter are not significantly different (Tukey HSD test, P <0.05).|