46 MISC. PUBLICATION 498, U. S. DEPT. OF AGRICULTURE 



the flesh in shallow areas. Under moist conditions pink spore masses 

 are produced from fruiting bodies scattered over the lesions. 



Except in severe cases the decay affects the edibility of the fruit 

 but little because of its shallow penetration and because under normal 

 conditions the fruit becomes ready for eating before the spots have 

 enlarged. However, the lesions detract markedly from the appear- 

 ance of the fruit and thereby affect the selling price. 



CAUSAL FACTORS 



The fungus causing anthracnose is the same one that causes anthrac- 

 nose of avocado (p. 35), grapefruit, orange, and papaya (p. 47). On 

 the mango tree it sporulates on the dead twigs and leaves from which 

 the spores of the fungus wash onto susceptible parts of the tree. The 

 fruit is more susceptible to penetration by the fungus before it is 

 half grown than after that time, but most of the early infections do not 

 become visible until the fruit begins to ripen. 



CONTROL MEASURES 



Control of the disease is difficult because of the amount of suscep- 

 tible tender growth on the tree at all times and because flower clusters, 

 which are most susceptible, are difficult to protect with a fungicide. 

 Bordeaux mixture, 3-3-50 strength witli a sticker, applied as the 

 buds swell, in the bloom, and while the fruit is developing, has been 

 found fairly successful for the control of the disease. Because the 

 fungus establishes itself in the skin early, fungicidal washes applied 

 to the fruit at picking time are of no value in controlling the disease. 



(See 7, 31,79, W.) 



Olives 



LOW-TEMPERATURE INJURY ai 



Low-temperature injury of fresh olives consists of a browning of 

 the flesh, which begins to develop after about 1 month's storage at 32° 

 to 40° F. (pi. 20, E and F). In early stages it can be detected only 

 by cutting the flesh, but after prolonged storage it is readily apparent 

 without cutting. Severely affected olives appear water-soaked when 

 cut (pi. 20, F). 



The browning develops only slightly, if at all, in olives held at 50° 

 F. but becomes progressively worse as the storage temperature is 

 lowered. At 50°, shriveling is a serious factor if the relative humidity 

 is low. 



SULFUR DIOXIDE INJURY 



Sulfur dioxide injury of fresh olives is characterized by sharply 

 sunken bleached areas that vary in size from mere pin points to areas 

 an eighth of an inch in diameter or sometimes slightly larger (pi. 

 20, G). They result from the placing of olives in a car or storage 

 room with grapes and then fumigating the space with sulfur dioxide. 

 So far as known, they are not subject to invasion by decay-producing 

 organisms. 



11 Pentzer, W. T. Unpublished notes on file in the Bureau of riant Industry, Washing- 

 ton, D. C. 



