A survey of seedling establishment in sugar-beet crops in 1980 and 1981

One hundred and twenty five crops distributed throughout the UK sugar-beet growing area were examined to identify the growth stage at which failures occurred during the seedling establishment phase. Establishment varied between 15 and 90% and averaged 64 and 67% in 1980 and 1981 respectively. It exceeded 70% in 46% of fields. Overall, the actual seed spacing was only 0·15cm wider than the 17·0cm intended but the number of seed stations in individual fields varied from 27% less to 19% more than the target. On average the drill failed to place a seed at 5% of seed stations but up to 14% misses were recorded. Germination in the field was 92% - only 1% less than in the standard laboratory germination test. However, on average, 16% (range 2 - 42%) of seeds which germinated failed to develop much further; the cause of only a quarter of these losses was identified as due to soil pests, diseases or being caught under stones or clods. There was a tendency for more seeds to fail between germination and emergence as the proportion of empty seed stations increased. Rapid emergence usually resulted in greater final emergence. There were post-emergence losses in 122 of the 125 fields. These losses averaged 6% and exceeded 14% on five fields. Birds were considered to have killed plants in 49 fields, soil pests caused losses in 20 fields and herbicides, fungal disease or grazing by rabbits or hares decreased plant stands in about 10 fields.