CLUBROOT 



WILLIAM L. DORAN 



CLUBROOT, a serious disease of 

 cabbage, broccoli, cauliflower, 

 and other crucifers, markedly 

 lessens production. With more than 

 3000 acres given over to the raising 

 of these plants in Massachusetts, 

 it is easy to see how economically 

 important it is for the vegetable 

 gardening industry of the State to 

 keep such crops free from the havoc 

 of fungi and insects. The well- 

 known author, Samuel Hopkins 

 Adams, must have been familiar 

 with this agricultural problem when 

 he wrote in Holiday, June 1951, 

 "No other product of the soil is so 

 buffeted by the winds of chance as 

 the humble cabbage leaf. Com- 

 pared to the risks of raising it, the 

 double zero on a roulette wheel is a 

 conservative investment." 



* Research Professor, Botany 



Soil-borne Disease 



The cause of clubroot is a fungus, 

 with the formidable name Plasmo- 

 diophora brassicaeWoT., which lives 

 in the soil, entering the plant 

 through the roots. The infected 

 roots become deformed, swollen, 

 and finally decay; meanwhile, 

 growth is stunted, and the plant 

 wilts and dies. 



If clubroot becomes severe, the 

 home gardener usually stops plant- 

 ing cabbage and related plants; 

 the commercial grower sometimes 

 resorts to a long rotation, which is 

 not always effective, probably part- 

 ly because of the presence of cruci- 

 ferous weeds, at least thirteen 

 species of which are known to be 

 hosts to this disease fungus; or, the 

 farmer may apply lime to the soil. 

 This procedure, however, does not 

 always prevent clubroot. 



