Further experiments on black-leg disease of sugar-beet seedlings

Soaking sugar beet seed for 20 min. in ten times its weight of water containing 40 p.p.m. ethyl mercury phosphate to control seed-borne Phoma betae gave better seedling emergence than surface treatments with commonly used organo-mercury dusts or with Panogen (methyl mercury dicyandiamide), thiram, Granosan M (ethyl mercury p-toluene sulphonanilide), captan, Dow 9 B (zinc trichlorophenate) or Cerenox (acylphenylhydrazone). In 4 years' field trials, soaking seed in ethyl mercury phosphate solution followed by dusting with an insecticidal dust, compared with a routine mercury-plus-insecticidal dust, increased seedling emergence at fifty-three of fifty-nine sites by an average of 10 % under good emergence conditions and by 20-30 % under adverse conditions. Final plant stand was increased each year by an average of 5.8, 3.4, 1.8 and 0.6 %, respectively.