Comparison of Progeny-Testing Methods in <em>Lolium perenne</em> L.

From 22 genotypes, selfed (S1) and testcross progenies were investigated. The latter were generated by i) polycross (PX) and ii) 2 topcrosses (TC) using cms-inbred lines as a tester. Progenies were tested for annual dry matter yield in 3 successive years, the 3-year average was 76.7 dt/ha for S2 and 76.9, 80.1 and 74.5 for PX, TC 1 and TC 2, respectively. Genetic variance was highest for S11 (20.42), while the average of the 3 testcrosses was 12.22. However, the genotype-year interaction variance of S: Was 52.21, being 2--3 times greater than for the 2 topcrosses. PX progenies were the most stable across years. Predicted response to selection was highest for S1 (10.4 %). Genetic correlation (rg) between S1 and the testcrosses was highest with TC 2 (rg = 0.593+ +). [ABSTRACT FROM AUTHOR]