FUNGI AFFECTING MELONS AND 



CUCUMBERS 



The Cucumber Mildew 



Plasmopara cubensis 



In America tliis disease lias been recognized as a 

 destructive enemy of cucumbers and other cucurbitaceous 

 plants for only three or four years, but it is already 

 widely distributed, and in many places has done much 

 damage. The fungus attacks the leaves in a manner 

 somewhat similar to the attack of the downy mildew of 

 the grape. The mycelium, after entering the leaf from 

 a germinating spore, develops between the cells, and 

 sends suckers into the cells to absorb their contents. In 

 due time this mycelium sends branches out through the 

 breathing pores of the leaf, on the tips of which are 

 produced the spores. The injured leaves turn yellowish 

 or brown in spots, and if the attack is severe, are finally 

 destroyed. 



The destruction of all refuse leaves that may have 

 been infested, and spraying with fungicides, are the best 

 remedial measures. A rather full account of the fungus 

 may be found in the eighth report of the Massachusetts 

 Experiment Station (pp. 210-212 ; 1890), and in Amer- 

 ican Gardening, April, 1803. 



The Bacterial BHght 



This disease has been esj^ecially troublesome in the 

 Southern States, where it has done much damage to the 

 melon crop. It is also destructive in the truck-growing 



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