The influence of seed vigour on field performance and the evaluation of the applicability of the controlled deterioration vigour test in oil seed rape (Brassica napus) and pea (Pisum sativum)

12 rape seed lots (3 cultivars each of 4 lots) and 9 pea seed lots (3 culti vars each of 3 lots) of various ages were used in laboratory tests and fiel d trials. Plants of older rape seed lots performed poorly throughout the gr owing season, and final seed yield was significantly lower compared to that of young seed lots. Germination percentage of rape seeds in a standard tes t correlated poorly with field performance, whereas germination after contr olled deterioration for 24 hours correlated significantly with plant growth in both sowings and with final yield in one sowing. Mean germination time in the standard test and after controlled deterioration had highly signific ant correlations with field performance and seed yield for rape seed in bot h sowings; the applicability of a vigour test for Brassica species based on germination rate is discussed. Seedlings produced by the older pea seed lo ts emerged more slowly than plants from the young seed lots, but difference s in growth characteristics diminished throughout the growing season. Diffe rences in seed yield were only slightly significant in one sowing. Controll ed deterioration improved the correlation of germination percentage and the mean germination time for pea seeds with field performance, but overall th e correlation with plant growth and yield was poor. The significance of the se findings is discussed.