Plant Insecticidal Proteins and their Potential for Developing Transgenics Resistant to Insect Pests

Insects cause heavy damage to cultivated crop plants. Production of proteinaceous inhibitors that interfere with the digestive biochemistry of insect pests is one of the naturally occurring defence mechanisms in plants. These proteins include lectins, arcelins and inhibitors of alpha amylases and proteases of various larvae pests. Use of plant genes encoding effective inhibitors of major digestive enzymes, such as protease and a-amylase inhibitors of the target pest species is emerging as viable approach for the production of pest resistant transgenic crop plants. Therefore, it is important to characterize proteins and their genes from our indigenous crops in order to strengthen and broaden our gene bank for pest control manipulations. The availability of diverse insecticidal proteins and their genes from different plant species will make it easier to use one or more genes in combination to develop resistant crop plants. Eventually, insect resistant transgenic plants will certainly prove more economic than any conventional control strategy if long-term benefit of transgenic crops especially factors such as environmental damage and human health risks are considered.