H. Egri BosnyáknéDepartment of Plant Production and Protection, Institute of Plant Science, Faculty of Agricultural and Environmental Science, Kaposvár University, H-7400 Kaposvár, Guba S. utca 40. Hungary
S. KeszthelyiDepartment of Plant Production and Protection, Institute of Plant Science, Faculty of Agricultural and Environmental Science, Kaposvár University, H-7400 Kaposvár, Guba S. utca 40. Hungary
Damage induced on soybean by Tetranychus urticae Koch (Acari: Tetranychidae) is easily recognizable. We were curious to know whether, in addition to this visual and quantitative damage, change occurs also in the nutritional value of the harvested product.
The Weendei analysis showed that as compared to the healthy items, the protein content (P=0.048) of the miteinjured seeds as well as their composition (P=0.048) has changed. No significant changes in the raw fat content could be confirmed by the statistical results of the study (P=0.643). Concerning the contents of raw ash (P=0.069) and raw fibre (P=0.859), there were no significant differences.
Three distinct changes in protein structure were confirmed by gel electrophoresis. Substantially less 69 kDa protein was detectable in the infested soybean, whereas no 48 kDa protein was present in the control sample; it only appeared in the infested ones. There was a higher amount of 30 kDa protein in the infested stock. In summary, alteration in the protein structure was caused by T. urticae, and changes were triggered in the protein content of the affected soybean plants. The protein structure-change in damaged soybean items caused further decline in the feed consuming capacity of farm animals.