EFFECTS OF SUNN PEST (EURYGASTER SPP.) SUCKING DEGREE IN GRAIN ON WHEAT QUALITY CHARACTERISTICS

Abstract

Sunn pest is the most important detrimental insect species for wheat in Turkey and neighbouring countries. Sunn pest reduce both wheat yield and quality. The aim of this study is to determine the effects of sunn pest sucking degree in wheat grain on two bread wheat (Triticum aestivum L.) quality. Experimental materials were formed by separating insect damaged wheat kernels into four categories as 1/4, 2/4, 3/4, and 4/4 according to their sucking degree. Main physical, chemical, biochemical, and technological characteristics of wheat groups were determined. Each wheat group had different quality characteristics and the increase in sucking degree (from 1/4 to 4/4) in sunn pest damaged wheat bulk caused to decrease on physical, biochemical, and technological characteristics. Golia variety was more sensitive than Sagittario in terms of sunn pest sucking degree. Protease and amylase activities, crude fibre and ash content of samples increased sharply; crude protein and starch content decreased partially; thousand kernels and hectolitre weight, largeness, falling number, and sedimentation values decreased accurately depending on increasing level of sucking degree in insect damaged wheat mass. Consequently; sucking degree in kernel had a strong effect on wheat quality characteristics and it is an important factor for evaluating insect damaged wheat mass properly. Therefore cereal industry should not only take damaged kernel ratio into consideration, but also sucking degree of insect damaged wheat mass must be considered. In classification of the sunn pest damaged grains, it should be, at least 1/4 and 2/4 sucked grains classified one group, 3/4 and 4/4 sucked grains classified another group. It would be also useful to give the proportion of these two groups in the insect damaged wheat mass.