Biomass yield of self-incompatible germplasm resources and their testcrosses in winter rye

Abstract

With 2 figures and 6 tables Abstract Winter rye is an ideal crop for the agricultural energy production because of its vigourous growth, high nutrient- and water use efficiency, and low input production. For the use in biogas plants, maximal biomass yield with dry matter contents of >30% is an essential breeding aim. The objectives were to analyse the potential of 25 germplasm resources of various geographic origin for the rapid improvement of biomass yield compared with 22 and 12 full-sib families selected for forage and grain use, respectively. Population per se and testcross performance with two testers were evaluated for early growth, heading, plant height, dry matter content and dry matter yield across seven environments (location–year combinations) harvested as whole plants at late milk-ripening. Dry matter yield ranged, on an average, from 130 to 141 dt/ha for population per se performance and from 150 to 158 dt/ha for testcross performance (0% water content). Genotypic variances were significant (P = 0.01) throughout, entry-mean heritabilities for biomass yield were moderate to high (0.67–0.91). In both materials, germplasm resources and forage rye had on average the highest biomass yield. The best individual entry was a population hybrid with ‘Florida Black’ as pollinator (173 dt/ha). Three released hybrid cultivars selected for high grain yield were among the entries with the lowest biomass yield at milk ripening. Germplasm resources showed significant genotypic correlations between dry matter yield and early growth, heading date, dry matter content in the testcrosses. Genotypic correlations between populations per se and testcrosses were significant and high for germplasm resources and forage rye. In conclusion, germplasm resources have a high potential for maximal biomass yield when whole-plant harvest occurs at milk ripening.