CHAPTER XIV 



INVESTIGATIONS ON GUMMOSIS 



As early as the year 1 882 BEI JERINCK published a short communica- 

 tion in a little known journal "Sieboldia", with the suggestive title 

 The gumming disease of fruit trees is contagious" i). Therein he stated 

 that he had succeeded (at Wageningen) in producing gummosis in a 

 completely healthy peach tree, by inserting small pieces of gum from 

 a gum-diseased tree under the bark of the healthy specimen. Control 

 experiments with similar wounds, but in which no gum was inserted, 

 showed no gummose formation. In a plum tree also, gummosis could 

 be produced by infecting it with small pieces of gum from diseased 

 peach branches. 



BEIJERINCK immediately attached important conclusions to these 

 findings, with reference to the care necessary in horticulture to pre- 

 vent the spread of gummosis. He also emphasized in this first publica- 

 tion that his observation might become of importance for the ob- 

 taining of technically important gums, such as those produced by the 

 Acacia's. 



In 1883 there appeared his first detailed publication on the "con- 

 tagiousness" of the giim disease 2 ), and although BEIJERINCK'S ideas 

 on this subject later underwent rather important changes, the publi- 

 cation is still more than worth the study. After further investigation 

 and after infection experiments, he came to the result that the trans- 

 mission of the disease succeeded only when in the pieces of gum there 

 were present spores of a fungus, which his friend Prof. C. A. J. A. Ou- 

 DEMANS - - who, as is well known, devoted himself for many years to 

 the study of fungi - - declared to be a new species of the genus Co- 

 ryneuni, and to which this mycologist gave the name C. Beijerinckii 3 ). 



Let it be stated here at once that R. ADERHOLD in Berlin (1902) 

 declared this fungus (which he isolated himself, but of which he also 

 received a culture from BEIJERINCK) to be identical with a fungus 

 found often in "Steinobstkulturen" and usually indicated as Clastero- 

 sporium amygdalearum Sacc., but to which he himself, on grounds of 



1) De gomziekte der vruchtboomen is besmettelijk, Sieboldia 27 Mei, 1882 (Verza- 

 melde Geschriften 1, 125-126). 



2 ) Onderzoekingen over de besmettelijkheid der gomziekte bij planten, Verhan- 

 delingen Koninklijke Akademie van Wetenschappen Amsterdam 1883. In BEIJE- 

 RINCK'S Verzamelde Geschriften 1, 321-357 the French translation, which appeared in 

 Archives Neerlandaises des Sciences Exacteset Naturelles 19, 43-102, 1884 is inserted. 

 Owing to an error, a reference to the earlier papier has been omitted there. 



') C. A. J. A. OUDEMANS, Hedwigia, September 5, 1883, Nr. 8. 



