

LIST OF DISEASES OF ECONOMIC PLANTS 89 



RAPHANUS. 



R. sativus, radish. 



Actinomyces scabies (Thax.) Gues., scab. Ohio, Ind. 



Albugo Candida (Pers.) O. Kuntze, white-rust. General. 



Alternaria brassicae macrospora Sacc, leaf-spot. Conn. 



Ascochyta sp., leaf-spot. Mass. 



Bacillus carotovorus L. R. Jones (Erwinia carotovora (Jones) Com. S. A. B.). 



soft-rot. N. Y. 

 Bacterium campestre (Pam.) EFS. (Phytomonas campestre (Pam.) Com. 



S. A. B.) black-rot. Ohio. 

 Cercospora cruciferarum Ell. and Ev., leaf-spot. Ala. 

 Corticium vagum Berk, and Curt., stem-rot. Mass., N. Y., Del., Ohio, 



111., Wash. 

 Erysiphe polygoni DC, powdery mildew. Tex., Mo. 

 Peronospora parasitica (Pers.) D By., downy mildew. Widespread. 

 Plasmodiophora brassicae Wor., clubroot. Conn., N. Y., Pa., Minn. 

 Puccinia sarcobati (Pk.) Bethel, rust. Southwestern States. 

 Pythium aphanidermatum (Edson) Fitz., black-root. Widely scattered States 



east of Miss. River. 

 P. debaryanum Hesse, damping-off. Va., Minn. 

 Sclerotinia sclerotiorum (Lib.) Mass., stem-rot. Minn. 



RESEDA. 



R. odorata, mignonette. 



Cercospora resedae Fckl., leaf -spot. Widespread east of Great Plains. 

 Corticium vagum Berk, and Curt., stem-rot. Conn. 

 Fusarium sp., root-rot, N. Y. 



RHAMNUS. 



R. cathartica, buckthorn. 



Cercospora rhamni Fckl., leaf -spot. N. J. 



Puccinia coronata Cda., crown-rust. Vt., N. Y., 111., Wis., Minn., Iowa, 

 N. Dak., S. Dak. 

 R. purshiana, cascara buckthorn. 



Cylindrosporium rhamni Ell. and Ev., leaf-spot. Idaho. 

 Marssonia rhamni Ell. and Ev., leaf -spot. Wash. 

 Phyllosticta rhamnigena Sacc, leaf-spot. Wash. 

 Puccinia coronata Cda., crown-rust. Pacific Northwest; Mont. 

 Septoria blasdalei Sacc. and Syd., leaf-spot. Calif. 



RHEUM. 



R. rhaponticum, rhubarb. 



Ascochyta rhei Ell. and Ev., leaf -spot. General east of Rocky Mts. 



Bacillus carotovorus L. R. Jones (Erwinia carotovora (Jones) Com. S. A. B.), 

 soft-rot. Ohio. 



Colletotrichum erumpens Sacc, anthracnose. Pa., W. Va., 111. 



Corticium vagum Berk, and Curt., stem-rot. N. Y., 111., Wash. 



Ozonium omnivorum Shear (Phymatotrichum omnivorum (Shear) Dug.), root- 

 rot. Tex. 



Peronospora rumicis Cda., downy mildew. Calif. 



Phyllosticta straminella Bres., leaf-spot. N. Y., Pa., Ind., 111., Minn., Mo., 

 N. Dak., Nebr. 



Phytophthora sp., crown-rot. N. J., Pa., Del., Tenn., 111., Mich., Mo. 



P. cactorum (Leb. and Cohn) Schroet., crown-rot. Pa. 



P. parasitica rhei G. H. Godfrey, foot-rot. Md., D. C, Va., Kans. 



Puccinia rubella (Pers.) Arth., rust. Nebr. 



Sclerotium rolfsii Sacc, stem-rot. Va. 



RHODODENDRON. 



Rhododendron sp., rhododendron. 



Armillaria mellea (Vahl) Quel., root-rot. Wash. 



Coccomyces rhododendri (Schw.) Sacc, leaf -spot. W. Va. (on R. maximum). 

 Coryneum rhododendri Schw., leaf -spot. Wash., Oreg. (on R. calif ornicum) . 

 Cryptostictis sp., leaf-spot. Pacific coast. 



Exobasidium vaccinii (Fckl.) Wor., hypertrophy. Pa., N. C, Fla., Ind., 

 Iowa, Wash., Oreg. 



