Muskmelon Diseases 155 



crs are distinct. The pollination is done by means 

 of a camel's-hair brush, where the pollen from the 

 male blossoms is rubbed on the stigma of the female 

 flowers. 



Diseases of the Muskmelon 



Like cucumbers, greenhouse muskmelons are sub- 

 ject to numerous diseases. 



Bacterial Wilt 



Caused by Bacillus tracheiphillus Ew. Sm. 



Symptoms. The symptoms of bacterial wilt are 

 very striking. At first a few leaves of the plant are 

 wilted. Soon after, the entire plant wilts and dies. 

 Upon cutting through an infected stem, one observes 

 a whitish viscid exudate that oozes out from the 

 vascular bundles of the cut surface. If one places 

 his finger on the viscid substance and then gently 

 removes it, the bacteria will be strung out into nu- 

 merous delicate threads resembling cobwebs. The 

 disease works quickly, and the change of leaf color 

 from bright to dull green is also sudden. Musk- 

 melons, imlike squash, show no tendency to recover 

 temporarily from wilt. 



Bacterial wilt is spread about through the bites 

 of leaf-eating beetles, such as striped cucumber 

 beetle {Diabrotica vittatd). 



The Organism. B. tracheiphilus is a short 

 straight rod with rounded ends. The organism oc- 

 curs singly, in pairs, or rarely in chains of four; it is 



