ROOT KNOT NEMATODE INFESTATION 17 



Shaw 1940 {213a): Tobacco in enclosure units showed less than 10 percent 

 severe infestation following bare fallow or certain highly resistant crops, 

 14 percent following peanuts, and 100 percent following tobacco or other 

 susceptible crops. In field plots, tobacco showed 11 percent severe 

 infestation following peanuts and 93.3 percent following tobacco (2-year 

 averages) ; in 3-year rotations, tobacco showed less than 10 percent 

 severe infestation following peanuts after cotton, the same following oats 

 and weeds after peanuts, less than 25 percent following cotton after 

 peanuts, and 93 percent following continuous tobacco (1 year's results). 

 [North Carolina.] 



Smee 1928 (214): Groundnuts can be seriously attacked; little risk "on very 

 slightly infected soil." Nyasaland. 



Watson and Goff 1937 (258): Harbors some root knot, which does not 

 materially interfere with growth; rated as No. 42 in order of suscep- 

 tibility [from okra. No. 1, to corn, No. 46]. Florida. 



Arctotis stoechadifolia (A. grandis), bushy arctotis. (C) 



Goff 1936 (96): Infestation to heavy; 51 plants free from galls in 2 



winter tests, only 1 free in the spring test (92 plants, 3 tests) ; average 



rating "very lightly infested." Florida. 

 Watkins 1929 (248): Annual arctotis rated as "resistant." Florida. 



Argemone sp., argemone, pricklepoppy. (C) 



Goff 1936 (96): No infestation found (21 plants, 1 test). Florida. 

 Arrhenatherum elatius, tall oatgrass. (C, N) 



Bessey 1911 (16): Nematodes not abundant and no injury observed. 

 Artichoke, see Cynara. 

 Artilleryplant, see Pilea. 

 Aster tradescanti, Michaelmas-daisy. (C) 



Goff 1936 (96): 56 plants not infested, 2 plants lightly infested (2 winter 

 tests) . Florida. 



Steinee, G. (Division of Nematology, Bureau of Plant Industry, 1939): 

 Considerable resistance. 



Aster spp., aster. (N) 



Watkins 1929 (248): Annual asters rated as "resistant." Florida. 



There are four or five reports of root knot on unspecified asters, and one on 

 A. alpinus. 20 Callistephus, winter-aster, reported infested in Denmark (23, pp. 

 468 and 496), has been erroneously cited as "Aster sp." 



Avena fatua, "broad-leaved oatgrass," wild oat. 



Godfrey 1935: 21 Infestation commonly observed to be light. [In 1930 

 Godfrey (94) reported a heavy infestation.] Hawaii. 



Avena sativa, oat. 



Balachowsky and Mesnil 1935 (6): Injuries on oats especially in northern 

 Europe and southern Australia. [No such reports are known for the 

 root knot nematode; the sugar-beet nematode, Heterodera schachtii, has 

 been reported on oats in Germany (134), m Sweden (179', see Reh, 

 below), and in South Australia (53). See also Gramineae.] 



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

 Hastings Hundred Bushel) heavily inoculated in greenhouse; 7 weeks 

 later this series showed only "a few very slight swellings." Alabama. 



Bessey 1911 (16): No infestation found on some varieties of oats, but some 

 are susceptible; nematodes not abundant and no injury observed; Var. 

 Winter Turf ("Virginia") used in rotation experiment -[no other vari- 

 eties named]. 



Frandsen 1916 (67): "We have succeeded in getting a marked infestation." 

 California. 



2» Buhrer, Edna M.. Cooper, Corinne, and Steiner, G. a list of plants attacked by the root 

 knot nematode (heterodera marioni). U. S. Bur. Plant Indus., Plant Dis. Rptr. 17: 64-96. 1933. 

 [Mimeographed.] 



21 See footnote 10, p. 11. 



286871°— 41- 



