264 STATE BOARD OF AGRICULTURE. 



As a further result of our investigations, it was found that injury has 

 been brought about for years by improper use of the wet method, and 

 this loss, though important, has been over-looked or assigned to some other 

 factor. 



BEAN WORK. 



The work of the Experiment Station has been reported in full in other 

 reports. Mr. Muncie closed his work in 1917 and submitted full report of 

 his findings, which has been published in Technical Bulletin No. 38. Mr. 

 Ray Nelson, Mr. Muncie's successor has taken as his problem, Bean Mosaic. 

 Although work by Mr. Nelson was interrupted by his absence from the 

 Station for about nine months during the first of the year, many interest- 

 ing observations on Bean Mosaic have been made. The statements of 

 Cornell investigations that the disease is carried in the seed have been 

 amply confirmed. It has been shown by observations on the diseased 

 plants that the most pronounced mottling occurs in the new leaves, in 

 the parts of the leaf nearest the veins, indicating the significance perhaps 

 of the vascular system in transference of the virus. 



It is too early in this investigation to report on the many lines of ex- 

 perimentation under way dealing with Bean Mosaic. Suffice it to say 

 that it is the opinion of the members of the Experiment Station staff that 

 in the mosaic group of diseases we have what are potentially the most serious 

 of all plant diseases. Here is a great group of troubles, whose cause probably 

 is an ultramicroscopic organism transferred in most cases by insects, 

 capable in some cases at least, of wiping out an entire industry. There 

 are places in Michigan where Peach Yellows is a household word and where 

 peach growing is no longer attempted. There is a variety of potatoes, 

 Bliss Triumph, that no one can raise at a profit. There are cucumber 

 fields that have never produced a dollar's profit, and salting stations that 

 have been sold for a song. All these are examples of the result of the work 

 of a mosaic disease. That such a disease is at work in Michigan bean 

 fields warrants most intensive investigation and it is the purpose of the Ex- 

 periment Station to attempt to discover the seriousness of the present 

 situation in Michigan fields. 



> In this connection, permit me to refer to the very promising fact that 

 the Robust bean developed by Professor Spragg of the Farm Crops de- 

 partment seems, in Mr. Spragg's latest tests which have been care- 

 fully checked by both Mr. Muncie and myself, and by tests at Cornell 

 University by Dr. Donald Reddick, to be extremely resistant to Mosaic. 

 In this bean there seems to be the resistant character which will afford 

 material for abundant work in plant breeding. 



MISCELLANEOUS WORK. 



Interesting results on the injury to plants by phenol fumes have ])een 

 obtained in a series of experiments conducted by Miss Gillette, a student 

 assistant in the laboratory. These results have been prepared for publica- 

 tion. Work on transportational diseases, in connection with Mr. Nel- 

 son, is l)eing contin\ic(l. Mr. Nelson has obtained very important results 

 showing the imi)()rtance of asphyxiation, such as results from poor venti- 

 lation,* high temperature, etc., in connection with a wide range of crops. 

 Work along this line is being continued. 



