Family Cucurbitaceae 247 



FRUIT ROT 

 Caused by Sclerotium Rolfsii Sacc. 



This form of rot is seldom serious enough to war- 

 rant any treatment. The fungus does not seem to 

 find the watermelon fruit as suitable a host as the 

 cantaloupe. On watermelons, rotting starts at a 

 bruise and at points where the melon touches the 

 ground. Decay is slow and is always indicated by a 

 cottony growth at the rotted area. 



BLOSSOM END ROT 

 Cause: probably due to fungi. 



This is a disease which attacks the blossom end of 

 the fruit (fig. 42 e) and causes a dry rot, but which 

 does not usually penetrate very deep. Nevertheless, 

 affected melons are unfit for the market, although 

 they ripen earlier and have a much sweeter taste. 

 The cause of this trouble is as yet unknown. How- 

 ever, numerous observations seem to indicate that 

 with at least one form of blossom end rot it seems to 

 be brought about by a dry spell and a lack of mois- 

 ture in the soil. This is especially the case in fields 

 where coarse manure is used instead of good compost. 

 In dry seasons, the coarse manure fails to decompose 

 properly and, at the same time, dries, and hence re- 

 sults in injury to the fruit. To prevent this, so 

 far as possible, only well rotted manure should be 



