168 



Family: PSEUDOMONADACEAE 

 Trite: Ps El) DOMONA DEAE 

 Genus : Phytomonas 



Phytomonas campestr I S (Pammel) Bergey et al. 

 Insect concerned: Plus ia brass icae ; Agriolimax agrestis L. 



Pammel (l895) first isolated Bacillus ( Phytomonas ) 

 campestr is from diseased rutabagas. Two years later Smith 

 (1897) showed experimentally that this organisn, which 

 causes "black rot of crucifers, could "be transmitted "by 

 slugs, Agriolimax agrestis L. , and the cabbage worm, 

 Plusia brass icae. No actual proof of the insect trans- 

 mission of this disease in the field has, as yet, been 

 forthcoming. 



For a description of this organism see Bergey's Manual 

 (5th ed. , page 1^8). 



* Pammel, L. H. 1895 Bacteriosis of rutabaga ( Bacillus 



campestr is , n. sp. ). Iowa Agr. Exp. Sta. Bui. 27, 



130-13 1 +. 

 Smith, E. F. 1897 Pseudomonas campestr is (Pammel), the 



cause of a brown rot in cruciferous plants. Zent. Bakt. 



II., 3, 28^-291, ^08-^15, 1^78-^86. 



Phytomonas medicaginis var. phaseol i cola 

 (Burkholder) 



Insect concerned: The thrip, Heliothrips femoral is . 



This bacterium was isolated from leaves, pods, and 

 stems of beans afflicted with halo blight. Buchanan 

 (1932) showed that this bacterial disease of beans was 

 transmitted by the thrip Heliothrips femoral is . The 

 bacterial lesions on the plants are always associated with 

 the feeding wounds of the insect. According to Leach 

 (19^0), the transmission appears to be incidental and 

 entirely mechanical and under field conditions the insect 

 is probably of little importance as a vector of the disease 



For a description of this organism see Bergey's Manual 

 (5th ed. , page 19*0- 



Buchanan, D. 1932 A bacterial disease of beans trans- 

 mitted by Heliothrips femoral is Reut. J. Econ. Entomol. , 

 25, ^9-53. 



