408 AGRICULTUEAL AND INDUSTRIAL BACTERIOLOGY 



sequence of which there is prompt wilting of the leaves. 

 Yellow, slimy masses of bacteria ooze from the surface of 

 the cut bundles, which are made yellow. Apparently the 

 bacteria may enter the plant throug 1 ! the roots or the water 

 pores and stomata. 



PSEUDOMONAS JUGALANDIS 



This organism causes a serious blight of English walnut 

 in parts of California. It is a typical yellow pseudomonad. 

 It produces discolored or black cankers on the nuts, injur- 

 ing them commercially. It also attacks the young shoots. 



PSEUDOMONAS MEDICAGINIS 



This organism is the cause of stem blight of alfalfa, a 

 disease of the first crop of this plant in certain parts of the 

 western United States. It is described as producing watery, 

 semitransparent yellowish or blue-green appearance on one 

 side of the stem. The bacterial slime oozes from the diseased 

 area. This dries, giving the stems a varnished appearance. 

 Occasionally the crown of the plant may be involved. 

 Apparently the bacteria gain entrance through cracks 

 caused by freezir>s> and thawing in the spring of the year. 



The organism diners from most of the other pseudo- 

 monads pathogenic for plants in that it produces a fluores- 

 cent green pigment when grown on agar. 



