16 MISC. PUBLICATION 4 98, U. S. DEPT. OF AGRICULTURE 



SCAB 



(See Grapefruit, Scab, p. 7, and pi. 1, D.) 



SEPTORIA SPOT AND STAIN 



(See Oranges, Septoria Spot and Stain, p. 31, and pi. 15, B.) 



STEM-END ROT 



(See Grapefruit, Stem-end Rot, p. 7, and pis. 5, A, and 6, A.) 



SOUR ROT 

 (Oospora citri-aurantii (Ferr.) Sacc. and Syd.) 



Sour rot develops occasionally on citrus fruits if they are over- 

 mature or have been held for a long time in storage. Lemons and 

 limes are more commonly affected than other species of citrus fruits. 



The decaying areas are at first water-soaked, slightly raised above 

 the healthy surface, and dark buff yellow. Later a thin water-soaked 

 layer of compact cream-colored hyphae develops on the surface. The 

 decay involves the tissues of the rind and segment walls more rapidly 

 than it does the juicy vesicles. It is extremely soft and mushy, so that 

 the decayed tissue sloughs off with slight pressure and smears over 

 the rest of the fruit in the package. In late stages the decay is char- 

 acterized by a sour, putrid odor. It is frequently accompanied by other 

 decays and by the larvae of insects. 



The causal fungus enters through wounds or areas in the skin 

 killed by other diseases. On limes it commonly follows spotting or 

 stylar-end break-down. After the decay has started in one fruit it 

 may spread to neighboring sound ones. When Oospora is associated 

 with other citrus-rotting fungi, the decay produced develops much 

 more rapidlv than if produced by any of the fungi alone. 



(See I#, 43,101,105^ 



SPRAY INJURY 



(See Oranges, Spray Injury, p. 32, and pis. 6. />, and 11, C-E.) 



THRIPS INJURY 



(See Oranges, Thrips Injury, p. 33, and pi. 18, B.) 



TRICHODERMA ROT 



(See Oranges, Trichoderma Rot, p. 34.) 



WATERY BREAK-DOWN 



(See Grapefruit, Watery Break-down, p. 10.) 



Limes 

 anthracnose 



(Gloeosporium limetticolum Clausen) 



OCCURRENCE, SYMPTOMS, AND EFFECTS 



Key (Mexican) limes received at the market from any of the com- 

 mercial producing regions are frequently affected with corky, scablike 



