Nov. 6, 1916 
Host Plants of Thielavia basicola 
295 
cereals—wheat (Triiicum spp.), oats (Avena sativa) , barley ( Hordeum 
spp.), and rye (Secale cereale) —com (Zea mays), potatoes (Solanum 
tuberosum), hemp (1 Cannabis sativa), flax (Linum usitatissimum), and 
sweet potatoes ( Ipomoea batatas ). With the vegetables the cabbage 
( Brassica oleracea), onion (Allium cepa), parsnip (Pastinaca sativa), 
carrot (Daucus carota), beet (Beta vulgaris), lettuce (Lactuca sativa), 
eggplant (Solanum melongena), and peppers (Capsicum annuum) appeared 
to be free from attack by the fungus; and of the fruits no infection could 
be obtained on strawberries (Fragaria spp.), raspberries (Rubus spp.), or 
blackberries (Rubus spp.). 
Infection could not be obtained upon the following plants, which 
were previously recorded by others as being attacked by T . basicola: 
Nicotiana rustica, Phaseolus multiflorus, Pastinica sativa, Scorzonera 
hispanica, Daucus carota , Apium graveolens, and Beta vulgaris . The 
failure to obtain infection on these hosts may be attributed to one or more 
of several obscure causes. The writer is inclined to believe, however, 
that these species which have been mentioned as hosts of T. basicola 
should not be included in the list of host plants. There is a small proba¬ 
bility of immune varieties or strains being used in the studies reported 
here. In an attempt to clear up this point different varieties of some of 
these species were used, but only negative results in infection were 
obtained. 
Phaseolus multiflorus and Nicotiana rustica are included as hosts of 
T. basicola by Kirchner (9). A search through the literature has failed 
to reveal earlier reports of these species as hosts. It is evident that 
Kirchner included these species because of their relation to known 
susceptible species, as no mention of any original observations of his 
own could be found. This conclusion is further substantiated by the 
fact that after repeated tests by the writer, these species appear to be 
immune to attack. 
Aderhold obtained very slight infections on Scorzonera hispanica, 
Daucus carota , Apium graveolens , and Beta vulgaris . His results were 
obtained, however, under quite artificial conditions and no doubt 
resulted from one form or other of injury to the roots. The conclusion 
was drawn that T. basicola was only a very weak parasite. All attempts 
to infect the above-named species, under the conditions of these experi¬ 
ments, show that these forms are immune or at least extremely resistant 
to attack by T. basicola . Aderhold’s conclusion (1, p. 465)— 
Der Verlauf der Erscheinung zeigte, dass der Pilz kein heftiger Parasit ist. Ich 
schliesse mich auf Grund dieser Versuche der Auffassung Sorauers an, der Zufolge 
besondere Verhaltnisse geboten sein mtissen, tun ihn zu einen wirklichen Schadiger 
zu machen— 
should, therefore, certainly not be taken to apply to other host plants of 
T, basicola . 
