DisEAsES OF VEGETABLES 1337 
disease attacks mainly weak plants and can be largely avoided by 
obtaining a strong vigorous growth. Soil sterilization is prob- 
ably of little or no value. 
Sclerotinia Rot (Sclerotima libertiana Fuckel). This disease 
appears to be of minor importance in this state. Attacked plants 
very quickly collapse into a soft slimy mass. It is caused by the 
same fungus as celery pink rot and can be recognized by the 
mold and fungus resting bodies mentioned under that heading. 
The disease can be practically eliminated from both greenhouse 
and outdoor beds by the early removal and destruction of affected 
plants in each crop. Soil sterilization is effective. 
MUSKMELON OR CANTELOUPE 
The important diseases are, with the exception of white pickle, 
the same as of cucumber and the same remedies are effective. 
ONION 
Smut (Urocystis cepulae Frost), Fig. 393. This disease is 
destructive in many localities where onions have been grown for 
several years with little or no rotation. It attacks only onions 
grown from seed. Black streaks occur in leaves and bulbs, which 
when broken open are found to be filled with a dark powder 
similar to the smut powder of the familiar grain smuts. The 
disease is caused by a fungus which gains entrance to the young 
seedlings from the soil. 
The application of a weak formaldehyde solution in the furrow 
with the seed at planting time is a satisfactory and extensively 
used remedy. The solution is made at the rate of one pound of 
40 per cent. formaldehyde to 25 gallons of water. It is applied 
at the rate of 150 gallons or more per acre by means of a can and 
delivery tube attached to the seed drill. Heavy rains within 24 
hours after planting may greatly reduce the efficiency of the 
treatment. A mixture of 100 pounds powdered sulphur and 50 
pounds lime, drilled into the furrow with the seed, is of value, but 
in general less efficient than formaldehyde. 
Blight (Peronospora schleideniana De Bary). This is a fun- 
gous disease similar to potato blight. Thorough spraying at 
regular intervals of about ten days with bordeaux, 5-5-50, con- 
