Utilization of Neem Extracted Substance, Bt and Entomopathogenic Nematode on Azolla’s lnsect Pest Control

Abstract

Azolla is a bio-fertilizer   which   is   used   as a  green    manure.  Azolla    grows    vigorously   by   means of asexual   or   vegetative    reproduction.   When azolla  is  in  a proper    environment,  its   production  as  green   manure   is approximately  3  ton/rai   which    contributes  as  5-10  kg  N/rai.   However, using   azolla   as   green   manure is unlikely acceptable   in   Thailand   because   azolla is  easily imfested   by   insects.  Thus, this study   was established to compare   three   kinds of biological control   products   which   are   environmental   friendly.   There   were   neem    extracted substance (azadirachtin, Aza),  Bacillus  thuringiensis (Bt)  and   entomopathogenic   nematode   (Steinernema carpocapsae,  Sc).  It  was  found  that   among the  biological   products   used  in  the   experiment,  Bt  corporated   with   Steinemema   carpocapsae  (Bt+Sc) were  the most    effective   product   on  Azolla’s   insect   caterpillars control.  As   a   result,   the highest   azolla   production   was gained.   For  other   products   namely   Bt,  Bt+Sc+Aza   and Bt+Aza   were  less   effective  on  the   caterpillars  control, Respectively.