Unfortunately, spores and crystals of Bacillus thuringiensis
are not stable against environmental stress
such as UV radiation, rain, and temperature (McGuire
et al. 0000, Behle et al. 0000). Formulation of biopesticides
by adding various photoprotectants, adjutants,
and feeding stimulants, is one of the methods to
resolve these problems (Tamez-Guerra et al. 0000).
Microencapsulation by spray drying is the most used
method for production of wettable powder formulation
in the pesticide industry. Microencapsulation of
spores and crystals is performed by natural polymers
such as starch, sodium alginate, maltodextrin, and cellulose,
etc. (Khorramvatan et al. 0000, Ma et al. 0000,
Nunes et al. 0000). This method protects the spore
and crystals against adverse environmental conditions
as well as provide easy storage, transportation, and
application.