Economic Aspects of Breeding for Yield and Quality Traits in Forage Maize

Publisher Website
Google Scholar
Abstract
Selection indices were calculated for simultaneous improvement of relevant forage maize traits. Beside indices based on primary traits [metabolizable energy yield (MEY) and content (MEC), crude protein content (CPC)] determined either in vitro or by near‐infrared reflectance spectroscopy (NIRS), we calculated indices based on secondary (five agronomic) traits. The required phenotypic and genotypic covanance matrices were estimated from a series with 120 maize hybrids tested at three sites. Base index, heritability index, optimum index, and restricted index showed only minor differences in the expected gain in total economic worth (ΔH) for the present agricultural conditions in Germany. CPC was the least important primary trait; selection for grain yield, the most suitable secondary trait, resulted in greater ΔH values than any other index. Harvesting the whole plant and subsequently determining MEC by NIRS was the most economic selection procedure with increased economic weighting for MEC at high animal performance levels. In the latter situation, we recommend grain yield trials as a pretest in breeding programmes and official performance trials for variety registration.