Technology for microencapsulations of botanical pesticide azadirachtin and its insecticidal effect

The botanical pesticide azadirachtin was microencapsulated using interfacial polymerization. The technical conditions for azadirachtin microencapsulation were optimized by orthogonal experiment. Results show that the encapsulating yield of azadirachtin reaches(83.16±1.22)% under the following conditions: the ratio of toluene-2,4-diisocyanate(TDI) to hexamethylenetetramine was 3︰4(m∶m) as the wall materials, the proportion of azadirachtin dry powder to wall materials was 30︰7(m∶m), the ratio of ethyl acetate??to xylene was 3︰2(m∶m) as solvent, respectively. Pot culture experiment shows that the microencapsulated azadirachtin has good insecticidal effects with bioactivity and a long effective duration.