Fumigant Toxicity of Ricinuscommunis L.Oilon Adults and Larva of Some Stored Product Insects

Abstract

In this study fumigant toxicity of castor oil on adults and larva of two stored product insectsTriboliumconfusumand  Trogonellagranarium was investigated.Three concentrations were prepared 2%,5% and10% respectively by using acetone,statistical analysis showed thathightest  mortality  for adults of  T.confusum were 23.333% and 26.666% at 2% and 10% of castor oil and all three concentrations  significantly caused high mortality but 10% of castor oil killed 100% of khaprabeetles.Results also showed that 5% and 10%concentrations of castor oil were the most effective  on  first , second and third larval instars of T.confusum, as they caused 60% and 66.6% mortality for the first larval instar,  50% and 63.3%  mortality for second larval instar and, 33.3% and 40%  for third larval instar  at 5% and 10% concentration respectively compared with 0% at control treatment,in addition the three concentrations of castor oil affected first ,second and third larval instars of T. granarium significantly ,the percentage of mortality was  86.6%, 90.0% and 93.3% for the first laval instar compared with 40.0% at control treatment, 70.0%,70.0% and 80.0% for second larval instars compared with 20% at control treatment,and 40.0%, 63.3% and 80.0% for third larval instar compared with 20.0% at control treatment, at 2%,5% and 10% concentrations respectively.In summary, results indicated that these essential oils have good fumigant toxicity on stored-product pests.

Keywords:essentialoiles,castoroil,stored product insects.