Harvesting hybrid and inbred sweet-corn seed in ENGLAND

Sweet corn is increasingly grown for seed in England. As the seeds are unusually susceptible to fungal diseases, especially if left too long in the ear, a better understanding is required of the relationship between seed harvesting and climatic conditions. Correct harvesting is essential for the different varieties grown in England, since they react differently to English climatic conditions. A study was therefore made of growing, harvesting, drying, threshing and storing hybrid and inbred sweet-corn seed in England. Inbred C 13 and its hybrid with Extra Early Bantam (John Innes Hybrid No. 1) were sampled between 12 September and 26 November, 1951. Harvestings on 23 October and 5 November gave the heaviest yields of hybrid, and on 5 November of inbred. Mature hybrid seeds were heavier than inbreds, the heaviest individual seed-weight of inbreds being on 8 October, and of hybrids on 23 October. Seed quality and appearance were best on 8 October for inbred and 23 October for hybrid, which could be harvested over a longer period without deterioration. Harvestings of 8 and 23 October gave most viable hybrid seeds, and inbred seeds from 24 September germinated best in the glasshouse, but inbreds from 23 October gave best germination outside. This indicates better adaptability of hybrid seeds. Seedling vigour is associated with harvesting date; inbreds were weaker and wilted more than hybrids. These results are discussed in relation to climatic conditions at the time of the experiment.