Sap feeding insects are mostly from orders Homoptera and Hemiptera .These insects are with short life cycle such as aphids ,psyllids mealy bugs .....etc.They are able to gain resistance quickly because they give several or many generations annually .The green peach aphid for example may give one generation in ten days so easily can gain resistance against repeated sprayed insecticides .
Isoclast belongs to a new and unique class of chemistry, known as the sulfoximines,but they are able to cause blocking to necotinic receptor in the nervous system such as neonicotinoid insecticides. Sap feeding insects are able to gain resistance despite no record up to now because they are still new group with limited use .They can gain direct and cross resistance.