Family Cucurbitaceae 221 



SOFT ROT 

 Caused by Bacillus melonis Gid. 



Soft rot is a disease which attacks the melon fruit 

 only. The losses from this trouble often run as high 

 as twenty-five per cent, of the crop. It is prevalent 

 in seasons with prolonged dry weather followed by a 

 wet spell. This results in the uneven growth and 

 development of the fruit and hence in various crack- 

 ings in its surface. Infection follows the place of 

 injury, especially when the crack (fig. 38 a) occurs 

 at a place where the cantaloupe touches the ground. 

 The rot produced is soft with an offensive odor. 



The Organism. Bacillus melonis is a short rod 

 (fig. 38 a) with rounded ends, occurring singly or in 

 short chains of two to three, and motile by means of 

 flagella. It forms no endospores, no capsule, and no 

 involution forms. It completely liquefies gelatine 

 in fourteen days. No gas is formed, and no very dis- 

 tinct odor is noticed. It dies by drying and exposure 

 to light. 



Control. Wherever possible, irrigation should be 

 resorted to'in dry weather. This will encourage 

 even growth and prevent cracking of the fruit. In 

 wet weather spraying with Bordeaux mixture is re- 

 commended. Occasional turning of the melons to 

 expose them to light on all sides will also help. Dis- 

 eased refuse should be destroyed and not be fed to 

 stock. 



DOWNY MILDEW, see CUCUMBER, p. 230. 



