192 The Philippine Journal of Science leis 



ate, sometimes crescent-shaped granular spores are produced 

 among the setae. The fungus has not been identified. 



Control. — The control is similar to that discussed under sootj^ 

 mold of citrus. 



WITHER tip: colletotrichum gloeosporioides penzig 



Symptoms. — A gradual dying of twigs and branches is fre- 

 quently produced by this fungus. Not only the twigs, but the 

 leaves and the fruit may be infected. The leaves wither, and 

 the twig is killed and shrinks, leaving a definite line of demarca- 

 tion between healthy and diseased wood. On the leaf, dark 

 brown spots are produced. The fruit beneath a withered tip 

 branch often becomes infected, which is evidenced by a russet 

 appearance. Minute black specks are produced over the diseased 

 surface. 



Causal organism. — The organism is evidenced by the acervuli, 

 produced in the form of black specks over the diseased parts. 

 The acervuli are formed under the surface, but later rupture it. 

 Setae are produced, and from a dense mass of short conidiophores 

 are produced the minute, cylindrical, granular hyaline spores. 

 The fungus grows well in pure culture, producing scanty myce- 

 lium, from which arise many small black fruiting bodies. 



Control. — All diseased portions should be removed by pruning 

 out well below the visible advance of the disease. Spraying with 

 Bordeaux mixture as discussed under citrus canker is effective. 



Gloeosporium intermedimn Sacc. is found on injured citrus 

 leaves, where it produces minute black specks in the gray injured 

 portions. Aschersonia sclerotoides Henn. may be found growing 

 parasitically on coccids that are on the leaves. A Micropenis 

 also may be found growing on leaves. 



COCOS NUCIFERA LINN. COCONUT 

 BUD rot: bacterial 



This is the most serious coconut disease in the Philippine 

 Islands, if not in the world. Fortunately it is severe only in 

 a few localities of the coconut regions, chiefly in Laguna, Batan- 

 gas, and Tayabas Provinces. These coconut sections are some 

 of the most extensive in the Islands and, unless control measures 

 are carried out, the disease will spread. 



Symptoms. — The first symptom is a withering of the youngest 

 unfolded leaf, followed by the leaf's turning brown. Gradually 

 other leaves wither and turn brov^m, until the entire central 

 group is affected. At this stage the disease is easily recognized 

 by the group of dead young leaves of the central bud, which has 



