Aug. 15, 1914 
Phomopsis Vexans on Eggplant 
335 
It is evident from a detailed study of the inoculation experiments that 
the fungus Phoma solani isolated from the stem of eggplant will also 
infect the fruit and leaves of the eggplant and that the fungus isolated 
from the fruit (. Phyllosticta hortorum) will infect the stem and leaves. 
Both of these organisms will cause a rapid damping-off of eggplant seed¬ 
lings. Judging from the results of the experiments here performed, both 
fungi are parasitic on Solanum melongena at any age, but not on Ipomoea 
batatas , Lycopersicon esculentum , Capsicum annuum , and Datura iatula . 
A careful study of infected plants show that the injuries produced by 
the two organisms are indistinguishable and that the evidence of infec¬ 
tion after inoculation is manifested in about the same length of time. 
No attempt has been made to recover the organisms from all infected 
plants. It has, however, been isolated from many infected leaves, 
fruit, and stems. Many plants have been inoculated with cultures of 
the organism recovered from previously inoculated plants, and the or¬ 
ganism has been recovered a second time from some of these infected 
plants. In fact, the four cardinal requirements, known as Koch’s 
rules, have been fulfilled in a number of instances as proof of the patho¬ 
genicity of the organisms used in the inoculation experiments. In view 
of results gained from inoculation experiments, it is evident that the two 
fungi, known as Phoma solani and Phyllosticta hortorum , are identical. 
They are also identical morphologically. 
TAXONOMY OF THE FUNGUS 
Spegazzini (1881, p. 67) described a fungus occurring on the leaves 
of Solanum melongena as Phyllosticta hortorum , the pycnidia of which 
measured 80 to 90/4 in diameter and the pycnospores 4 to 6/4 long and 
2 to 2.5/* wide. Halsted (1892, p. 279) reported the same fungus on 
the leaves and fruit of Solanum melongena in New Jersey, and at the 
same time he also reported (1892, p. 277) damping-off or seedling stem- 
blight of eggplant, which he described as Phoma solani . Smith (1904) 
published a short note to the effect that he had found Ascochyta lyco¬ 
persici on the leaves and fruit of Solanum melongena . He says “the 
fungus differs from Phyllosticta hortorum Speg., both in size and septa- 
tion of spores and in character of leaf spot.” He further says that “a 
careful comparison with Halsted’s material showed the two to be dis¬ 
tinct”; also that “the spores of Phyllosticta hortorum Speg., in mate¬ 
rial collected by Halsted agree in size with those given by Saccardo, 
4-6X 2-2.5/4, while those in this Ascochyta are nearly twice that size, 
6-12X3.5-4/4.” Smith, with the fungus he had, was able to infect 
Solanum melongena , Lycopersicon esculentum , Solanum carolinense, and 
Datura iatula . The following year he (Smith, 1905, p. 10-14) seems to 
have thought that the organism he had under observation the year before 
was Phyllosticta hortorum Speg., which “manifested slightly different 
characteristics from that of the previous year.” According to his obser- 
