October 2004. The bean pod borer Maruca testulalis is a serious pest on beans in the Cook Islands. Information was sought on new insecticides, such as “Success”, “Spinosad” or “Steward “(Indoxacarb). Would they give effective control? Is there any information available about the withholding period on beans with these chemicals? Currently most farmers use “Attack”, but are looking for more selective insecticide with a shorter withhold period.
Papua New Guinea reported that it had runn a screening trial for “Success” for Brassica pests (especially caterpillars: Hellua undalis, Plutella xylostella, Spodoptera litora and Croccidolomia binotalis) and found it to very effective compared to conventional insecticides such as Karate and Delfin. There were also trials with “Steward” also on brassica caterpillars, which again was effective. But no trials wiht these chemicals have been done on bean pod borer. Both insecticdes have high ovicidal effects. Withholding period for leafy vegetables is 3 days (bean is not included) for Success.
DPI&F, Queensland aslo reported good control using Spinosad on an experimental crop to control Maruca. Applying the product at egg hatch or on early instar stages is important to get the best result. The withholding period for green beans and peas in Australia is 3 days.
Vanuatu reported excellent control of M. testularlis with Dipel (Bt).
The is a description on Maruca vitrata (syn. M testularlis) on Ecoport: http://ecoport.org/perl/ecoport15.pl?SearchType=entityDisplay&=19604&entityType=AR****&entityDisplayCategory=full&menuStyle=icon