Answered

what is the chemical nature of alkoloids and which alkoloid is used to control insects in field

Answer :

ALKALOIDS ARE NITROGENOUS BY PRODUCTS AND POISONOUS.THESE ARE STORED IN DIFFERENT PARTS OF PLANTS .
NICOTINE WHICH WILL BE OBTAINED FROM THE PLANT NICOTIANA TOBACCUM(TOBACCO) IS USED TO CONTROL INSECTS IN FEILD
They are nitrogenous by- products and poisonous. They are stored in diffetent parts of plants.Nicotine is alkoloid and helpful as insecticide for killing insects in Tobacco plant( Nicotine Tobacco). Pytethroids is alkloid and helpful as insecticide for killing insects of Crysanthemum.