THE DRY ROOT-ROT OF THE BEAN 

 Walter H. Burkholder x 



Very little consideration has been given to the diseases that affect the 

 bean plant (Phaseolus vulgaris L.) below ground. During the past few 

 seasons an investigation of bean diseases in New York State by the writer 

 has shown that such diseases are veiy common and frequently very 

 destructive. The most important of these, and one that is enphytotic 

 to the western bean section of the State, is the dry root-rot. This disease 

 affects all the commercial varieties of the dry shell beans, and, so far as 

 known, all those used for canning purposes. The dry root-rot may occur 

 also on other species of Phaseolus. The following are affected: the 

 tepary bean (P. acutifolius Gray var. latifolius Freeman), the scarlet 

 runner bean (P. multiflorus Willd.), the moth bean (P. aconitifolius J acq.), 

 the lima bean (P. lunatus L.), and the adzuki bean (P. angularis Willd.). 

 The disease has likewise been observed on the Black-eye cowpea (Vigna 

 sinensis [L.] Endl.) and the kulti bean (Dolichos biflorus L.). 



In New York State the disease is of general occurrence. It has been 

 observed in 90 per cent of the bean fields of the six largest bean-producing 

 counties, and is found wherever the crop has been grown to any extent. 

 Specimens of bean plants affected with the dry root-rot have been received 

 from A. H. Gilbert and G. A. Meckstroth, of the United States Bureau 

 of Plant Industry, collected at Burlington, Vermont, and Grand Rapids, 

 Michigan, respectively. 



It is not known when the dry root-rot first appeared in New York 

 State. A few growers claim to have observed it for at least twenty-five 

 years. Since it is now of such general distribution in the bean sections, 

 apparently it must have been present for a long time. As far as known, no 

 reference to this disease has ever been made in literature except by the 

 writer (1916 and 1917), and these references apply to New York State. 

 The disease therefore evidently originated in this region or was introduced 

 from a locality where it has not attracted attention. The symptoms of 

 the disease above ground are not striking and could readily be mistaken 



1 The writer wishes to acknowledge his indebtedness to Dr. Donald Reddick for helpful suggestions 

 and criticisms during the progress of this work. 



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