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Meal crops & diseases. 
JOURNAL OP ACBCmm ISEAtd 
Vol. XXXI Washington, D. C., July 15,1925 No. 2 
BEAN VARIETAL TESTS FOR DISEASE RESISTANCE 1 
By R. D. Rands, formerly Pathologist , and Wilbur Brotherton, Jr., 2 Assistant 
Physiologist , Office of Cotton , Truck, and Forage Crop Disease Investigations , 
Bureau of Plant Industry , United States Department of Agriculture 
INTRODUCTION 
The discovery or development of disease-resistant varieties of beans 
(.Phaseolus vulgaris L.) has been recognized for several years as the 
most promising line of investigation looking toward the prevention 
of large annual losses. Several American and European investi¬ 
gators have published valuable evidence on the reaction of the com¬ 
moner bean varieties to the different diseases. Unfortunately, most 
of the standard American varieties have proved to be susceptible to 
one, two, and frequently all the major troubles. 
Hybridization has been resorted to, but this is complicated and 
time-consuming in securing resistance to anthracnose because of the 
variation in reaction among the varieties to an undetermined num¬ 
ber of biologic forms of the causal fungus, Colletotrichum Unde - 
muthianum (Sacc. and Magn., B. and C.). No variety resistant to 
all the known biologic forms has hitherto been reported. 
The success of the Cornell workers in combining the specific dis¬ 
ease resistance and other desirable characters of two or more varieties 
of beans into one strain is sufficiently well known to need no review. 
Considering the many different types of bean varieties, their geo¬ 
graphic distribution, climatic adaptation, and market requirements, 
the necessity for an abundance of resistant types with which to work 
is realized. The absence of such has been a serious handicap to the 
plant breeder. This paper presents the results of an extensive search 
for resistant material. 
A large collection of local and foreign varieties and species of beans 
has been made and tested. Although it was realized that many of 
the foreign varieties would probably not be adapted to direct com¬ 
mercial utilization in the United States, they might, through posses¬ 
sion of unusual resistance to one or more diseases, be valuable for 
hybridization with susceptible American types. While the informa¬ 
tion here given is in many respects preliminary in character, in 
others it seems conclusive enough to warrant bringing it to the atten¬ 
tion of other investigators. 
NOMENCLATURE AND AUTHENTICITY OF VARIETIES USED 
The names adopted by Jarvis ( 6 ) 3 have been generally used in 
listing the standard American varieties. Those introduced since the 
publication of his bulletin in 1908, or of uncertain classification, are 
1 Received for publication June 30, 1924; issued September, 1925. 
2 Resigned April 2, 1925. 
3 Reference is made by number (italic) to “Literature cited,” p. 153. 
Journal of Agricultural Research, Vol. XXXI, No. 2 
Washington, D. C. July 15,1925 
Key No. G-481 
59837—25f-1 
( 101 ) 
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eiRSAL INVESTIGATIONS. 
