156 EXPERIMENT STATION RECORD. 



The cost of applying the Bordeaux-Bug Death mixture was greater than where 

 Bordeaux mixture or Paris green was employed, so that the difference in net gain 

 between the two is less than indicated above. The greater efficiency of the Bordeaux- 

 Bug Death mixture is attributed to its more adhesive power. 



Downy mildew, or bligiit, of potatoes, ( i. P. Clinton ( Connecticut State Sta. Rpt. 

 1904, pt. 4, pp. 363-384, pis. 6").— In 1902 the author began a series of spraying exper- 

 iments with potatoes to determine the amount of injury due to Phytophthora infestans, 

 and, secondly, to determine the most effective and practical method of spraying to 

 prevent it. In this report he presents the results and offers suggestions based upon 

 the experiments thus far carried out. 



While the blight fungus is one of the most serious pests of the potato in Connecti- 

 cut, the author states that frequently injuries caused by other organisms are attrib- 

 uted to it. The results obtained in spraying with Bordeaux mixture vary with dif- 

 ferent seasons, but depend largely on the thoroughness of the treatments and their 

 application at the proper time. Increased yields due to spraying, varying from almost 

 nothing to over 100 per cent, are noted; to be economically profitable the author 

 says that an average gain of 15 to 20 per cent should be obtained. 



Where late potatoes are sprayed for the blight the author advocates 3 to 4 thorough 

 applications of Bordeaux mixture, the first to be made between July 5 and 15 and the 

 last about the end of August or first of September. 



"Wet rot" of potatoes, C. T. Musson and G. Marks (Agr. Gaz. X. S. Wales, 16 

 {1905), No. 2, pp. 186-193, figs. 4). — A disease of potatoes, to which the name "wet 

 rot" is given, is described. 



In the field the disease rapidly destroys plants here and there in the rows, but 

 seldom are contiguous specimens attacked. The isolated plants exhibit characters 

 which are attributed to attacks of bacteria, and it is believed that the organism is 

 present in the seed tuber and develops with the development of the plant. Investi- 

 gations have been carried on to determine this fact, and the authors believe it to be 

 thoroughly demonstrated that the disease is transmitted through the seed tubers. 



There is no external indication of the presence of the disease in the harvested 

 tubers, but if cut in two characteristic brown spots, running in an irregular line 

 throughout the tuber, are to be found. All such tubers should be rigorously excluded 

 in planting, and if the crop shows signs of disease, all plants attacked should be dug 

 up and destroyed at once. 



Downy mildew, or blight, of muskmelons and cucumbers, G. P. Clinton 

 {Connecticut State Sta. Rpt. 1904, pt. 4, pp- 329-362, j>k. 3). — A description is given of 

 the downy mildew or blight of muskmelons, in which the early record, distribution, 

 host plants, systematic position of the fungus, its life history, etc., are described. 

 The fungus, which has hitherto been referred to the genera Peronospora and Plas- 

 mopara, the author shows is entitled to generic rank, and he proposes for it the name 

 Peronoplasmopara cubensis. 



A review is given of experiments which have been carried on in different places 

 for the control of this disease. The consensus of opinion seems to favor the spraying 

 of cucuml >ers with Bordeaux mixture for their protection. From the author's experi- 

 ments, based on 3 years' investigations with muskmelons, it is concluded that when 

 the downy mildew is very severe spraying the muskmelons is useless, but when sea- 

 sons are cold and damp and the fungi are not unusually destructive, spraying may 

 show some benefit. During warm dry seasons, such as are necessary for the develop- 

 ment of muskmelons in Connecticut, the fungus does not occur abundantly enough 

 to warrant spraying; and everything considered, the spraying of muskmelons is not 

 to be recommended in the State. 



A bibliography of nearly 70 publications relating to this fungus and the disease it 

 causes is given. 





