CULTURES OF UREDINEAE IN 1910 



J. C. Arthur 



The present article is the eleventh of a series of reports^ by the 

 writer upon the culture of plant rusts, beginning in 1899. Almost 

 uniform progress has been made during the twelve years in the 

 prime purpose of the work, that of experimentally connecting the 

 sporophytic and gametophytic phases of heteroecious rusts, as 

 well as the study of autoecious species and in some cases the 

 detection of races. The work of the year is representative in 

 these several respects. It was under the charge of Miss Irma A. 

 Uhde, a senior student in general science in the University of 

 Iowa, who was recommended by Professor Thomas H. Macbride. 

 Miss Uhde conducted the work with fine insight and untiring 

 patience, securing a notably large number of successful infections. 

 Some of the sowings, particularly those of the cedar rusts were 

 made and the records kept by Dr. F. D. Kern. All the work was 

 done under the auspices of the Indiana Experiment Station, and 

 financed from the Adams fund. 



There are some very common American rusts that collectors of 

 culture material are likely to send in considerable abundance every 

 year, such as Puccinia Caricis, P. Peckii, P. angustata and the 

 Aster-Solidago-Erigeron group among the sedge rusts, and P. 

 poculiformis, P. pustvilata, P. Andropogonis, P. Impatieutis and 

 P. fraxinata among the grass rusts. These are usually sown, 

 although the life cycle is known, and when time and opportunity 

 permit some tests are made regarding their less known aecial 

 hosts and the possibility of races. While these and similar 

 species take time that could usually be put upon less known forms 

 to better advantage, there is another set of common rusts often 

 sent by collectors, whose life cycle is not known, such as Puccinia 

 emaculata, P. Ellisiana, P. vexans, and the form on Carex Pciin- 



^ See Bot. Gaz. 29: 268-276; 35: 10-23; Jour. Myc. 8: 51-56; 10: 8-21; 

 11: 50-67; 12: 11-27; 13: 189-205; 14: 7-26; Mycol. i: 225-256; and 2: 

 213-240. 



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