broth. 

 Source: Five strains were isolated from 



FAMILY IV. ENTEROBACTERIACEAE 349 



Broth: Turbid, with sediment. No pellicle Methyl red test is positive, 



formed. Citric acid, as well as sodium alginate, 



Litmus milk: Acid after 24 hours. .^^ be used as a sole source of carbon. 



Potato: Abundant, yellowish gray growth. t^t-^ ■. 11/. -, . 



, , , ^ , , 6 j& Nitrites produced from nitrates. 



Indole not produced. t^, , 



Hydrogen sulfide production is abundant. ^^^^'^ '^^^^"^ ^° hemolysis. 



Alginic acid is decomposed with the Aerobic, facultatively anaerobic, 



production of acid and gas. Temperature relations: Optimum, 30° C; 



Acid and gas from glucose and lactose good growth at 37° C; grows at 4° and 



(slow). Acid from fructose, arabinose, 45° C. 



galactose, raffinose, xylose, maltose, su- Chemical tolerance: Grows at pH 9.6. 



crose, salicin, glycerol, dulcitol, iso-dulci- r',^^ . i^ a ^^,. „„..+ ^^- ^ 1,1 ■ i 



, ' • , , , • , , • . Grows in per cent sodium chloride 

 tol, manmtol and sorbitol; de.xtnn is 



usually attacked. No acid from starch or 



inulin. 



Acetylmethylcarbinol is produced soil. 



(faintly). Habitat: Presumably soil. 



TRIBE II. ERWINIEAE WINSLOW ET AL., 1920. 



(Jour. Bact., 5, 1920, 209.) 



Er.wi.ni'e.ae. M.L. fem.n. Erwinia type genus of the tribe; -eae ending to denote a 

 tribe; M.L. fem.pl.n. Erwinieae the Erwinia tribe. 

 Characters as for the genus. 

 There is a single genus. 



Genus VI. Erwinia Winslow et al., 1917* 

 (Jour. Bact., 2, 1917, 560.) 



Er.wi'ni.a. M.L. gen. noun Erwinia of Erwin; named for Erwin F. Smith, pioneer Ameri- 

 can plant pathologist. 



Motile rods which normally do not require organic nitrogen compounds for growth. Pro- 

 duce acid with or without visible gas from a variety of sugars. In some species the number 

 of carbon compounds attacked is limited, and lactose may not be fermented. May or may 

 not liquefy gelatin. May or may not produce nitrites from nitrates. Invade the tissues of 

 living plants and produce dry necroses, galls, wilts and soft rots. In the latter case, a proto- 

 pectinase destroj-s the middle lamellar substance. 



The type species is Erwinia amylovora (Burrill) Winslow et al. 



Key to the species of genus Erwinia. 



I.f Pathogens that cause dry necroses, galls or wilts in plants but not a soft rot {Erwinia 

 sensu stricto). 



* Completely revised by Prof. Walter H. Burkholder, Cornell University, Ithaca, New 

 York, July, 1954. 



t The genus Erwinia as defined here is heterogeneous in nature and is composed of at 

 least two distinct groups. The first group constitutes Erwinia proper and does not produce 

 visible gas from sugars. Waldee (Iowa State Coll. Jour. Sci., 19, 1945, 435) has suggested 

 that the species in this first group be placed in a separate family, Erwiniaceae. 



