64 MISC. PUBLICATION 4 6, U. S. DEPT. OF AGRICULTURE 



Experiments indicating nematode resistance in Var. "Roode Star" were re- 

 ported by Dorst (55) . The nematode in question- was not named and no clue 

 to its identity can be found in the paper. In the Netherlands it is often the 

 bulb-and-stem nematode, Ditylenchus dipsaci, that causes trouble in potatoes; 

 in other parts of Europe potatoes are injured by the sugar-beet nematode, 

 Heterodera schachtii; these two nematodes are probably more important than 

 root knot in the Netherlands. 



Var. Burbank. 



Headley 1918 (108) : Russet Burbank is supposed to be more resistant than 

 the smooth Burbank. 



Var. Irish Cobbler. 



Cunningham 1936 (51) : Tuber infestation fairly light, and later than in 

 other varieties (moderate in Var. Bliss Triumph, severe in Green Moun- 

 tain) ; roots of all three varieties heavily infested. New York (Long 

 Island) . 



Solidago spp., goldenrod. (C) 



Bessey 1911 (16): "Species of Solidago also free." 

 No reports of infestation in this genus have been found; possibly the roots are 

 seldom examined. See Weeds. 



Sorghum halepense (Andropogon halepensis) , Johnson grass. (C) 



Barrons 1939 (18) : Numerous larvae entered root tips of seedlings heavily 



inoculated in greenhouse. Alabama. 

 Bessey 1911 (16): No infestation found. 



Smee 1928 (214)'- "Johnston grass . . . immune . . . (South Africa)." 

 [No authority can be found for this statement except Fuller (70), who 

 had acknowledged, in a general way, his use of Bessey's (16) material.] 



Sorghum vulgare (Andropogon sorghum; Holcus sorghum), sorghum. 



Barrons 1939 (13): Numerous larvae entered root tips of seedlings (Var. 



Sagrain) heavily inoculated in greenhouse. Alabama. 

 Bessey 1911 (16): No infestation found on the various forms of sorghums, 



milos, kafir, etc. 

 California Nematode Committee 1925: 32 Resistant. 

 Collins 1938 (41) : Kafir not attacked (1 season). Rhodesia. 

 Godfrey 1928 (92): Infestation light on "Smilo" [Question: What plant 



was meant?]; infestation extreme on "Red milo maize" [meaning Dwarf 



Yellow Milo?] and on "Sorghum amber cane" [meaning Amber sorgo?] 



(one test each). Hawaii. 

 King and Hope 1934 (127): Sorghums beneficial in rotation for control. 



Arizona. 

 Krishna Ayyar 1933 (131, 182): Always found free and soil population 



reduced; no infestation found in pot experiment. India (Madras). 

 Watson 1929 (255): Sorghum usually "immune" or only slightly infested. 



Florida. 



Sorghum vulgare var. sudanense, Sudan grass. (N) 



Collins 1938 (4-1): Rhodesian Sudan grass not attacked (1 season). Rho- 

 desia. 

 Georgia Coastal Plain Experiment Station 1936 (S3) : Somewhat 



susceptible. 

 Tyler 1938 (237) : Viable eggs found in greenhouse experiment. [Infesta- 

 tion light.] District of Columbia. 



Sorrel, see Rumex. 

 Soybean, see Soja. 

 Speedwell, see Veronica. 

 Spider-flower, see Cleome. 

 Sprouts, see Brassica. 

 Spurge, see Euphorbia. 

 Squash, see Cucurbita. 

 Statice, see Limonium. 

 Stick-tight, see Bidens. 

 s - See footnote 6, p. 8. 



