CULTURAL AND CHEMICAL CONTROL OF FUNGAL ROOT ROTS AND ROOT MAGGOTS IN COLE CROPS
KF CHANG1, SF HWANG2, RJ HOWARD1, P RAGAN1, LM DOSDALL2 and B CHOBAN3
1Crop Diversification Centre South, Brooks, Alberta, Canada, T1R 1E6; 2Alberta Research Council, Vegreville, Alberta, Canada, T9C 1T4; 3 Crop Diversification Centre North, Edmonton, Alberta, Canada T5B 4K3
Background and objectives
Results and conclusions
Fungicide trial: while no significant differences in disease severity or lesion length were observed between control and inoculated plots, average weight per head and total cauliflower production per plot were significantly greater in control than in inoculated plots. Overall, plants in fungicide-treated plots had shorter lesion lengths and lower disease severities than those in non-treated plots. Similarly, total weight per plot was significantly higher in the fungicide-treated plots than in the non-treated plots. Average weight per head was significantly greater for the Terrachlor and Bravo treatments than for the non-treated control. Lower disease severities were observed in plots treated with Benlate than those treated with Zineb.
Fungicide and insecticide trial: inoculation did not produce significantly lower head weights in the insecticide study. All treatments significantly reduced lesion lengths and disease severities, and increased total harvest and individual head weights. Diazinon and Lorsban, when combined with Benlate, resulted in significantly shorter lesions than when Benlate was used alone.
Mortality of cauliflower and cabbage seedlings was affected by planting method, whether by transplanting or direct seeding. On average, twice as much mortality occurred in direct-seeded cauliflower as in transplants. In cabbage, transplantings produced less mortality than direct seeding. Evidently, early transplanting of cole crop seedlings is advantageous for reducing the mortality caused by pathogens and pests.