THE IMPORTANCE OF WESTERN CORN ROOTWORM IN CONTINUOUS MAIZE

• Main Authors: Marija Ivezić, Ivana Majić, Emilija Raspudić, Mirjana Brmež, B. Prakatur
• Format: Article
• Language: English
• Published: Faculty of Agrobitechnical Sciences Osijek 2006-06-01
• Series: Poljoprivreda
• Subjects: Western Corn Rootworm; maize hybrids; continuous maize; root damage; grain yield
• Online Access: http://poljoprivreda.pfos.hr/upload/publications/6_IVEZIC.pdf

Western Corn Rootworm (Diabrotica virgifera virgifera LeConte) is considered to be one of the most important and potentially most severe pest of maize worldwide. The pest was detected in Croatia for the first time in 1995. Since then it has been spread over all areas with maize production in Croatia. The economically most efficient and preventive control measure is crop rotation and growing maize hybrids that show tolerance to WCR. The trials were settled in the area near Dubosevica where in 2002 and 2003 the economic damages caused by WCR were up to 80%. The aim of this investigation is to determine damages on maize root caused by WCR and loss in grain yield on commercial maize hybrids in continuous farming. Pheromone traps, type Csal♀m♂N®, were used in order to monitor WCR population dynamics. In the period of two months, 366 WCR adult beetles in total were captured. Root damage was evaluated according to Iowa Node Injury Scale and grain yield was measured and corrected to 14% moisture. Furthermore, the plant lodging, as a consequence of larval feeding, was assessed. The results have shown that root damage for hybrid Bc 5982 was 1.15, and 0.73 damage was on Pr 35p 12 roots. The grain yield obtained from hybrid Bc 5982 was 11.7 t/ha, and Pr 35p 12 had 12.3 t/ha. Statistical analyses showed that there were no significant differences in root damage and losses in grain yield between the two investigated hybrids. Results of this investigation indicate that growing maize for 2 to 3 years in continuous farming, in the same field, would not cause economically significant loss in maize gain yield.