European corn borer (Ostrinia nubilalis Hbn.) -- international sources of resistance and their use for the development of Central European breeding material.

摘要

In the years 1999 and 2000, 18 and 34 lines and populations of maize, respectively, from Iowa, Missouri, Mexico and South Africa were tested for resistance to the European corn borer, Ostrinia nubilalis. Additionally date of flowering and dry mattercontent of the ear at harvesting time were documented, to compare the adaptation to the central European climate. The two well adapted European dent lines D408 and D06 were chosen as standards. The plants were manually infested with 60 neonate larvae per plant. The following resistance traits were examined: the relative damage of the plants, (relationship of damaged and non-damaged plants), amount of larvae alive at harvesting time in the plant, and in the year 2000 additionally an evaluation using a damage rating scale for stalk breakage from 1 to 9 (1=no damage, 9=stalk breakage under the ear). The lines and populations from Iowa and Missouri showed in 1999 and 2000 a higher level of relative damage, more larvae per plant at harvesting time and a higher stalk breakage in the year 2000 than the other material, except the European standard. All maize lines and populations had a lower dry matter content and a later date of flowering than the two European dent lines. Therefore it could be supposed thatthe material is not as well adapted to the European climate. The results showed a good resistance level of the international material, even if some breeding process is necessary to develop an earlier-maturing material.