ROOT KNOT NEMATODE INFESTATION 39 



Var. "California" [meaning Var. Shanghai?]. 



Burtch 1930 (27): Seems to be fairly free. California. 

 Var. Creola. 



Poole and Schmidt 1929 (195): Resistant; potatoes infested (3 percent) in 

 cracks and lenticels (1 season). North Carolina. 



Var. Dixie " Yam." 



Poole and Schmidt 1929 (195): As resistant and as productive as Var. 

 Porto Rico on infested soils; rootlets infested at tips, potatoes slightly 

 scabbed (2.3 percent; 2 seasons). North Carolina. 



Var. Enormous. 



Poole and Schmidt 1929 (195): Resistant; roots slightly infested, also 

 potatoes (3.5 percent; 1 season). North Carolina. 



Var. Gold Skin. 



Poole and Schmidt 1929 (195): Resistant; very slight infestation of potatoes 



(0.2 percent; 1 season). North Carolina. 

 Whittle and Drain 1935 (263): Listed as seldom infested or highly re- 

 sistant. 



Var. Japan Brown. 



Poole and Schmidt 1929 (195): Resistant; rootlets infested at tips, potatoes 

 scabbed (3 percent; 1 season). North Carolina. 



Var. "New Gem." 



Poole and Schmidt 1929 (195): As resistant and as productive as Porto 

 Rico; slight infestation in roots, 2.1 percent in potatoes (2 seasons). 

 North Carolina. 



Var. "Old Long Red." 



Poole and Schmidt 1929 (195): Resistant; slight infestation' in rootlet 

 tips, scablike lesions on a few potatoes (1.2 percent; 2 seasons). North 

 Carolina. 



Var. Porto Rico. 



Poole and Schmidt 1929 (195): The Porto Rico strains and varieties have 

 been very resistant throughout the infested areas; infestation slight 

 in rootlets and in cracked potatoes (1 to 1.8 percent; 3 seasons); Var. 

 "Golden Porto Rico" resistant also (1 season); potatoes slighty infested 

 (2.1 percent) through cracks and lenticels. North Carolina. Porto 

 Rico roots and potatoes sent by R. C. Thomas from Tifton, Ga., showed 

 slightly greater infestation than was observed in North Carolina. 



Tyler, J. (Divison of Nematology, Bureau of Plant Industry. 1939): Heavy 

 infestation observed on one planting, with fewer salable potatoes than 

 from the Nancy Hall, supposedly a much more susceptible variety, in 

 adjacent rows. Grower said the severe splitting and the irregularities 

 of size and shape in both varieties were directly connected with root knot 

 infestation. Virginia. 



United States Bureau of Plant Industry 1927 : 60 Reported as very 

 resistant by the assistant farm adviser in Los Angeles County, Cali- 

 fornia. 



Weimer and Harter 1925 (261): Highly resistant, not immune; yield 

 better than other varieties tested; a dozen galls found in one test, no 

 galls seen in two other tests (1 season). California. 



Whittle and Drain 1935 (268): Listed as slightly infested. 



Var. Red Jersey. 



Poole and Schmidt 1929 (195): Resistant; infestation to slight in rootlets, 



to 0.8 percent in potatoes (3 seasons). -North Carolina. 

 Weimer and Harter 1925 (261): Highly resistant, not immune; "no galls 



seen" in seedbed nor in three tests (1 season). California. 

 Whittle and Drain 1935 (263) : Listed as seldom infested or highly resistant. 



60 Haskell, R. J., and Wood, Jessie I. diseases of vegetable and field crops other than cereals 

 in the united states in 1926. U. S. Bur. Plant Indus., Plant Dis. Rptr. Sup. 54, pp. 209-333, illus. 1927. 

 [Mimeographed.] See p. 270. 



