ANTHRACNOSE OF CUCURBITS. 59 
As to resistant varieties, it should be mentioned that among water- 
melons the citron is somewhat resistant, while practically all varieties 
of cucumber and muskmelon tested are susceptible. 
SPRAYING. 
As was pointed out in the historical account, many workers have 
held Bordeaux mixture to be an effective control for this disease, 
_ and the same opinion seems to be rather widely held at the present 
time. 
At Princeton in 1915 plat tests were made of a variety of commer- 
cial sprays and of various Bordeaux formule. None of the applica- 
tions seemed to control anthracnose, since it spread consistently 
through the sprayed rows. 
In 1916 at Madison block tests were made with Bordeaux mixture 
(3-6-50: formula plus soap) and row tests with Pyrox and other 
strengths of Bordeaux mixture. Anthracnose spread through the 
sprayed rows as well as the controls, and neither observational nor 
yield-record evidence indicated that any of the spray applications 
controlled the disease. Its severity was, however, somewhat checked 
by the sprays, since it was very serious in only 5 out of 17 sprayed 
rows, as compared with 7 out of 11 unsprayed controls. 
To gain some insight into the effect of the presence of the spray 
upon leaf infection, a series of atomizer inoculations were made on 
August 13 upon the upper surfaces of certain leaves and the lower 
surfaces of other leaves among the sprayed rows. Well-sprayed 
leaves were chosen. The results of these inoculations are presented 
im lable XxX. 
TABLE X.—Results of atomizer inoculation of sprayed cucumber leaves at Madison, Wis., 
Un LOLGe 
Spray treatment. Bomeer of teurace d Results, Aug. 24. 
INOMC See SUR LO eee ee PCA Ee Bee 1 jeBothhees2. es. ts 
TD oye eee ty gOS SIR As ok ek BS neta LOM Uppers. ee es —(8located. Noinfection). 
JDO SE 2s Ot A 8 UE Lad, Me a Oe LOW Owens ess 2 ? 
Bordeaux mixture, 3-6-50formula........... LON Uippenscga... - —(9 located). 
TD) Pa ei Ie isin a ea Sha Ae ae 10 | Lower.........| +(9 located; all infected). 
IDX) 05 SU = Ni et age wa a a BOL PU DDeES sees _ ; 
ED) ORE SPN ee ge ER LE BA 25 | Lower........- +(7 typically infected). 
Bordeaux mixture, 2-4-50 formula.......... Donic Uppel-rensee _ 
VDC) Pa Gee eee tes Se I Mh eer a ce Ua 25 | Lower.........| +(6 typically infected). 
Bordeaux mixture, 4-6-50 formulas ee 25 | Upper.........| — 
TBO} Siete Maca 5 WC Le sade ace ae tm a Odi) WOW eTeo.s.4one +(4 typically infected). 
IP WAKO. Ge BSA Meas PES ARE ae Se Oe 945}) |) UN DOOR ssesaoee — 
JD) OR A Se ee Ae eR Ae ae a at ey ee 2 a 25 | Lower.........| +(9 typically infected). 
While natural infection interfered to some extent with these tests, 
no unquestionable atomizer infection occurred in any case where tine 
upper epidermis of sprayed leaves was inoculated, while in all cases 
some typical atomizer infection was secured where the lower epidermis 
of sprayed leaves was inoculated. Of these leaves, only the upper epi- 
