ROOT KNOT NEMATODE INFESTATION 59 



Ribes spp. (C) 



Buhrer, Cooper, and Steiner 1933: 20 Listing of red currant as a host was 



probably a misinterpretation, unfortunately copied by later authors. 

 Whittle and Drain 1935 (268): Currant and gooseberry listed as seldom 

 infested or highly resistant. Tennessee. 



The California State Department of Agriculture has an unpublished record of 

 infestation on R. grossularia, gooseberry. 



Rice, see Oryza. 



Richardia scabra (Richardsonia scabra), "Florida pursley," "Mexican-clover." 



Georgia Coastal Plain Experiment Station 1935 (81): More resistant 

 than crabgrass. 



1936 (83): Can be used successfully for control rotation. 



Gilbert 1921 (89): Mexican-clover a susceptible weed. 



Godfrey 1935: - 1 Infestations distinctly heavy. Hawaii. 



Neal 1889 (176): A fine substitute for susceptible cowpeas. Florida. 



Watson, Goff, and Bratley 1937 (259) : One of the most seriously infested 

 weeds in watermelon fields. Florida. 



Ricinus communis, common castor-bean, castor-oil tree. (C) 



Collins 1937 (41): No signs of nematode attack. Rhodesia. 

 Krishna Ayyar 1933 (132): No infestation found in pot experiment. India 



(Madras). 

 Naude 1939 (175): Castor-oil plants were found heavily infested. South 



Africa (Oudtshoorn). 

 Sandground 1922 (207): Parasitized more or less severely in South Africa 



(Basutoland, Natal, or Transvaal). 



Roquette, see Eruca. 



Rosa spp., and hybrids, rose. (N, S) 



Hume 1937: 22 All roses are attacked, but show much variation in the extent 



of damage; Var. Mme. Plantier does not suffer seriously. Florida. 

 McClintock 1930 (149): None resistant; marked differences in vigor; two 



vigorous growers which might be used in selecting for tolerance are 



R. multiflora and P. I. No. 22449 (R. banksiae; called "U. S. D. A. 



Odorata 22449"). Tennessee. 

 Watson and Goff 1937 (258) : For Florida conditions, roses should be grafted 



on a resistant stock, such as the "Texas Wax" rose. 



There are numerous reports of injury to roses; some of these possibly refer to 

 the varieties named above. Reh (198) mentioned rose as tolerant because of its 

 capacity for new root growth; the source of his quotation has not been found. 



Rosary-pea, see Abrus. 

 Royal sweet-sultan, see Centaurea. 

 Rubbertree, see Hevea. 



Rubus spp. (C) 



Florida State Plant Board 1921 (66): Infested shipments intercepted, one 



of blackberry from North Carolina and two of raspberry from Florida. 



Gardner 1926 (75): R. idaeus, European raspberry, and R. subuniflorus, 



"blackberry," observed to be hosts. California. 

 Morris 1934 (167): Blackberry selection Halls Lawton shows little suscep- 

 tibility to attack; all late-maturing varieties, e. g., Alfred, Blowers, 

 Eldorado, and others, have proved more susceptible to infestation than 

 the earlier maturing varieties. Texas. 

 Neal 1889 (176): R. subuniflorus (R. villosus), "blackberry," Bnd R. triv- 



ialis, southern dewberry, "slightly affected." Florida. 

 Selby 1897 (210, 211): Galls H to \% inches in diameter on blackberry and 

 raspberry roots and stems; "eel worms ... on the outer portion of the 

 galls below ground." Ohio. [These "eelworms" were not identified, 

 though "referred to Heterodera." In his 1910 handbook (212) Selby 

 described crown gall on raspberry, but did not mention nematodes.] 

 Whittle and Drain 1935 (263): Blackberry, dewberry, and raspberry listed 

 as slightly infested. Tennessee. 



20 See footnote 20, p. 17. 

 2i See footnote 10, p. 11. 

 " See footnote 5, p. 8. 



