EVALUATION OF INSECTICIDE SPRAYS AGAINST BANANA RUST THRIPS, 1998:

R. F. L. Mau and L. R. Gusukuma-Minuto
University of Hawaii CTAHR
Dept of Entomology
3050 Maile Way, Rm. 310
Honolulu, HI 96822
Phone: (808) 956-7063
FAX: (808) 956-5888
e-mail: maur@avax.ctahr.hawaii.edu
 
T. Y. Hata
University of Hawaii CTAHR
Beaumont Agri. Res. Cnt.
461 W. Lanikaula St.
Hilo, HI 96720

 

BANANA: Musa cavendishii

‘Williams Hybrid’

Banana rust thrips;

Chaetanaphothrips

signipennis (Bagnall)

 

Efficacy trials were conducted from 2 Jul through 22 Sept at a commercial banana farm at Keaau, HI. Twenty immature banana bunches ready for bagging (industry standard) were selected and thrips populations visually accessed before treatment. Treatments were applied on 2 Jul with a compressed air sprayer equipped with an adjustable hollow cone nozzle (47 ml per bunch) at 35 psi. Each treatment was applied to 4 banana bunches selected at random. A spreader sticker, Latron B-1956 (Rohm and Haas, Philadelphia, PA) was added to all treatments at a rate of 2.0 fl. oz. per 100 gal. Insecticide sprays were allowed to dry before bagging. Banana bunches were harvested on 22 Sep and the percentage of thrips injured hands per bunch recorded. Percentages were transformed by arcsine transformation and subjected to ANOVA.

There was no sign of thrips injury on bananas prior to treatment. Provado and both rates of Success significantly reduced the percentage of damaged hands per bunch with thrips injury. There was no significant difference among Provado and Success treatments. Diazinon-500 AG is the current industry standard for banana rust thrips control. Diazinon was not included in the analysis due to severe thrips injury in one replicate only. Phytotoxicity was not observed with any treatment.

 

Treatment/formulation     Rate lb (AI)/100 gal         % hands with thrips injury
Provado 75WP     0.047         0.0b*
Success 6.0 fl. oz.     0.094         0.0b
Success 8.0 fl. oz.     0.125         5.6b
Check     ---         48.6a
Diazinon 500-AG1     0.5         25.0
Means followed by the same letter in a column are not significantly different by Waller-Duncan K-ratio t test, Kratio=100.
*Significant by ANOVA P>0.05.
1Diazinon not included in analysis due to severe thrips injury to one replicate only.

 

 

Trade Composition\
Common name
    Formulation         name     Source
Diazinon     EC         diazinon     Prentiss
                       
Provado     F         imidacloprid     Bayer
                       
Success     SC         spinosad     Dow AgroSciences