Published online by Cambridge University Press: 27 March 2009
Since sugar beet was first grown on farms it has been difficult to establish single seedlings at the required spacing because each seed unit was liable to produce a cluster of seedlings. Plant breeders have introduced varieties with monogerm seed and these were used between 1960 and 1962 to see if they led to any savings in labour with hand and machine thinning and to determine the yields of beet after these treatments. The trials described show that, after machine thinning, predetermined final plant populations with 90% of single seedlings were obtained and, when a herbicide was effective in weed control, the labour requirement was about 5% of that required to hand single a crop from multigerm seed. When singled by hand the monogerm varieties required 90 % of the labour needed to single a multigerm crop but the mean yield per acre of the monogerm varieties used was at least six tons per acre less than that from a commercial variety with multigerm seed.