Combined vigour tests to estimate relative seedling emergence in the field and germination after storage in sweet corn seed lots

Abstract

This study was carried out to test whether the radicle emergence (RE), cold (CT) and accelerated ageing (AAT) tests and their combinations of CT+RE and AAT+RE can be used to rank sweet corn seed lots according to field seedling emergence and germination after storage. Seed samples for eight hybrid seed lots were stored hermetically over 12 months at 20°C with 9.9-10.2% seed moisture. RE was counted between 32 and 72 hours, AAT was carried out at 41 ± 1°C and 100% RH for 72 hours, and CT at 5°C over two days. RE count was performed after AAT (AAT+RE) and CT (CT+RE). Seedling emergence was tested in two field sowings, in April and May 2022. The vigour test results were correlated with both seedling emergence percentages in the field and germination after storage. Both normal germination after CT (r = 0.73-0.94, P < 0.05-0.001) and AAT+RE72h (r = 0.71-0.84, P < 0.05-0.01) were significantly related to both parameters. The RE test was significantly related to seedling emergence, but not to any post-storage data. The normal seed germination percentage was found to be significant in only one case (sowing 2). Seed vigour in sweet corn seeds and its importance in relation to seedling emergence and seed storage are discussed.