Overlap effects of cyromazine concentration, treatment method and rearing temperature on the Southern cowpea weevil (Callosobruchus maculatus F.) reared on cowpea

Journal Article

• Magazine \ Newspaper: African Journal of Microbiology Research
• Issue Number: 32
• Volume Number: 5
• Pages: 5848-5853

Publication Abstract

Overlap  of  insect  growth  regulator  (cyromazine)  concentration,  treatment  method  and rearing 
temperature  was  studied  on  the  southern  cowpea  weevil,  Callosobruchus  maculatus  F.  (Bruchidae: Coleoptera),  under laboratory conditions.  A concentration of  5%  cyromazine  and  dipping  treatment  at 30°C  showed  a  significant  reduction  in  the  reproductive  rate  by  0.5%.  Moreover,  increasing  thecyromazine  concentration  led to  a  decrease  in  food  consumption.  Hence, treatment  of  cowpea  seeds via  dipping  method  provided  more  protection  compared  to  spraying  method.  Also,  the  increase  of cyromazine  concentration  led to  an  increase of  generation's  lifespan.  The longest generation  lifespan recorded was  33.33  days when treated with 5%  cyromazine  by dipping  at  30°C. On the other hand,  the shortest generation  lifespan  recorded was 25.33 days  when treated with  1%  cyromazine  concentration by  dipping  at  30°C.  This study showed  that there is no effect of the overlap between  studied  factors, neither in the disparity of sex ratio nor in the disparity of males and females body weights.