But does not harm other organisms . the toxin gene in different strains of b . thuringiensis can affect different mixes of insects so seed makers can select the version that seems best suited to a particular crop 不同的苏力菌菌株，各有不同的毒基因，影响的昆虫也不同，所以种籽生产商可以针对特定的作物，选用最适合的抗虫基因。
