Evaluation of the relationship between numerical and weight percentage of kernel damaged by sunn pest, Eurygaster integriceps

One of the major damage of sunn pest, Eurygaster integriceps, is its destructive effects on the quality of wheat grains, which is known as sunn pest kernel damaged. Nymphs and adult of the bugs inject salivary glands enzymes by piercing-sucking mouthparts into the grains, which degrade glutens, reduce dough and bread wheat quality. Grain damage percentage is calculated by the both numerical and weighing methods. In this research, an experiment was conducted to compare the relationship between these two methods. We measured 225 damaged wheat grain samples delivered from Arak (n = 30 × 3), Ghazvin (n = 20× 3) and Lorestan (n = 25× 3). A digital scale with 0.1 mg precision was used to weigh kernels. For these samples, the number and weight of damaged and undamaged grains were recorded. In general, undamaged kernels with an average weight of 34 mg were heavier than damaged ones with average weight of 30 mg. Although, there was a significant difference between the numerical and the weight values, a significant positive correlation (r = 0.98; P