116 DISEASES OF TROPICAL PLANTS 



CH. 



which usually needs a legume crop to give the necessary 

 improvement for a return to cotton. 



Nematodes on the cotton are well known in the 

 United States and the West Indies, and probably have 

 a much wider distribution. 



CITRUS FRUITS 



The citrus fruits are both tropical and subtropical, 



FIG. 51. Lemon twigs affected with wither tip, Colletotrichum gloeosporioides. 



and the most important diseases to which they are 

 subject appear to be as widespread as the hosts. 



Wither Tip ; Leaf- Spot ; Lemon Spot ; Canker ; and 

 Anthracnose. This disease (Figs. 51, 52), which is known 

 by so many names, is probably the most destructive 

 fungus disease known to the citrus fruits. It is due to 

 the fungus, Colletotrichum gloeosporioides, 1 Penzig. 

 It attacks the lime, lemon, orange, pomelo, and probably 



1 Colletotrichum gloeosporioides, Penzig. Syn. Vermicularia gloeosporioides, 

 Penzig ; Phyllosticta adusta, E. & M. ; Colletotrichum adustum, Ell. 



