1959 Volume 28 Issue 4 Pages 257-266
1. Since 1954 the authers have carried out seed treatment investigations for principal vegetable crops with the view of examining the physiological and pathological effects of seed-soaking on seed germi-nation and growth of young seedlings, and the effects of seed protectant treatment on improving vegetable stands. The present report includes the results of experiments on carrot seed dressing per-formed during the period from 1955 to 1958.
2. In the field trials, carrot stands were improv-ed by dressing seeds with fugicidal dusts, especi-ally with thiuram (Arasan, Pomasol Forte, and Kawasen), dichlone (Phygon), and chloranile (Sp-ergon).
3. In the greenhouse experiments, carrot seeds naturally infected with Alternaria radicina were sown on steamed soil. This fungus proved to be
responsible for carrot damping-off, especially in the pre-emergence phase. The dressing treatment was effective in improving the stands by control-ling damping-off.
4. In the germination tests on Petri dishes, most fungicides used more or less inhibited seed germination and also the growth of radicles. Practically, however, the inhibiting effect seemed to be negligible when seeds were sown in soil.
5. The effectiveness of the dressing treatment appeared to vary with the following factors: den-sity of fungal infection of seeds, temperature of seed beds, and depth of seeding.
6. Recommendation based on the trials is the dressing carrot seeds with Arasan, Pomasol Forte, Kawasen, Phygon, or Spergon at the dosage of 0.75 percent of dehaired seeds by weight.