Date of this Version
Thesis (M.S.)—University of Nebraska—Lincoln, 1971. Department of Horticulture and Forestry.
Common blight and fuscous blight bacterial diseases are important diseases of beans in many production areas of the United States.Effective and reliable inoculation methods to identify tolerant and susceptible disease reactions are needed in breeding beans tolerant to these pathogens.The research reported in this thesis involved the comparison of leaf water-soaking and stem inoculation procedures.
The experiments were conducted in three different environments. Field plots were grown at Lincoln and the Scotts Bluff Station and inoculated with common blight and fuscous blight bacteria.A greenhouse study, in which the common blight organism was used, was also conducted.
In both locations in the field, the spray inoculation produced good visual symptoms of both diseases.This method can be used to inoculate rapidly large populations of plants.Under field conditions the scalpel method gave poor visual disease symptoms.A large number of plants showed stem breakage when this method was used.The scalpel method requires a great amount of time and would not be a good method where large plant populations are involved.
The Tepary varieties showed no visual disease symptoms when inoculated with both organisms.G. N. Nebraska #1 selection 27, G. N. Tara, and California Small White showed good tolerance to the bacteria causing both diseases.
The greenhouse study indicated that the scalpel method might be very useful in distinguishing degrees of susceptibility.Under greenhouse conditions the spray method showed G. N. 1140 and Tendercrop to be similar in susceptibility.However, almost all the Tendercrop plants died as a result of the scalpel inoculation while plants of the G. N. 1140 only showed slight stunting.
Advisor:Dermot P. Coyne