Amylase activities in insect (Aelia and Eurygaster)-damaged wheat

The extent of modification of wheat amylase activities caused by Aelia and Eurygaster attack on wheat grain was determined in different Spanish cultivars subjected to varying degrees of attack. High variation in diastatic activity and alpha-amylase and beta-amylase activities was found between cultivars, but no relationship could be established between these activities and bug damage within cultivars. Scanning electron micrographs of the cross-section of damaged kernels showed an empty cavity under the bite point. The surrounding cell walls and protein matrix were absent, but the starch granules were intact. Since wheat damaged by Aelia and Eurygaster does not have altered amylase activities, it appears that amylolytic enzymes are not involved in the alteration of bug-damaged wheat. (C) 2002 Society of Chemical Industry.