254 Glomerella cino^ulata and its Conidial Forms 



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perfect stage was developed. Sub-cultures from the original culture C, 

 taken after a lapse of 2, 3, and 10 months on glucose- meat-extract-agar 

 and other agar media, gave only the perithecial stage. Single spore cul- 

 tures of ascospores and asci have produced only the perithecial stage, the 

 conidial being absent. 



From the behaviour of the chilli Glomerella in cultures it appears 

 that Colletotrichum nigrum and Gloensporium piperatwn are one and the 

 same fungus, the conidial stage being generally without setae in Bihar 

 (either the setae are developed only under certain conditions or only 

 certain strains are capable of producing setae). The development of 

 setae is not a constant feature of the genus Colletotrichum. The well- 

 known bean disease C. Lindemuthianum forms pustules very often with- 

 out the least trace of setae; in fact this bean anthracnose was first put 

 in the genus Gloeosporium. The same is true of the anthracnose on 

 cucurbits. It was first named G. lagenarium but when setae were later 

 found it was placed in the genus Colletotrichum. The anthracnose of 

 tomatoes Chester^ described in 1891 as caused by C. lijcopersici n.sp. as 

 there was an abundant development of setae in the acervuli, but in the 

 following year the diseased spots were without setae and to all appearance 

 the fungus was a Gloeosporium and therefore Chester raises the question 

 whether the presence or absence of setae is of sufficient generic importance 

 to separate the two genera. Edgerton^ considers the distinction between 

 the Gloeosporium and Colletotrichum so poor that he prefers to drop the 

 name Colletotrichum in favour of Gloeosporium in his discussion on the 

 development of anthracnoses. According to Kriiger^ Colletotrichum and 

 Gloeosporium cannot be sharply divided into two distinct genera and 

 therefore he considers Colletotrichum as a sub-genus. Miss Stoneman'* 

 has found the presence of setae so variable as to doubt whether they 

 form a well-founded basis for distinguishing these two genera. Shear 

 and Wood^ are also of the same opinion. They have found setae in the 

 acervuli in one part of a pure culture, whereas in other parts of the same 

 culture they were absent. They^ have also found this same variation 

 occurring upon leaves, especially in the form found upon cranberry. 



1 Chester, F. D. Ddaivare Station Report Jar 185)1, \>\k (IO-G:? and for 1892, p. 80. 



- Edgerton, C. W. Loc. ciL, p. 3(59. 



^ Kriiger, F. Loc. cit.. p. 303. 



' Stoneman, B. Loc. cit., p. 70. 



'^ Shear, C \j. and Wood, A. K. Ascogenous Forms of Gloeosporium and Colletotrichum. 

 Bot. Gaz.. XLiii, p. 2G3, 1907. 



' Slicar, C. L. and Wood, A. K. Studies of Fungous Parasites belonging to the Genus 

 Glomerella. U.S. Dept. Agr., Bur. PI. Ind., Bull, No. 262, p. 64, 1913. 



