232 



The Philippine Journal of Science 



Control. — Dusting with sulphur or the use of any standard 

 fungicide is recommended. 



PSOPHOCARPUS TETRAGONOLOBUS DC. WINGED BEAN, CALAMISMIS 



ORANGE GALLS: WORONINELLA PSOPHOCARPI RACIBORSKI 



Symptoms. — The leaves, stems, and pods are seriously at- 

 tacked. Leaves may be entirely covered with the yellowish to 

 orange rustlike pustules. They are more abundant on the lower 

 surface, but are also found on the upper. Growth of the younger 

 leaves is retarded, and they may assume abnormal shapes or 

 become thickened. The characteristic, rustlike pustules are pro- 

 duced on the stems. The growth of stems may be entirely 

 stopped. They often become gnarled, twisted, and abnormally 

 enlarged. Large pods may be entirely covered with the yellow- 

 ish to orange pustules, making them undesirable for use. 

 Growth of smaller pods may be checked or they may grow 

 abnormally, producing malformed, unsalable pods (Plate XV, 

 fig. 2). 



Causal organism. — A section through galls in the plant shows 

 the abnormal formation of the host tissue. In the center of the 



galls is a cavity with the orange- 

 colored spores, sporangia (fig. 

 27). These sporangia may ger- 

 minate in one hour. The con- 

 tents break up into small proto- 

 plasmic masses, which issue from 

 an opening in the wall of the 

 sporangia as free-swimming 

 swarm spores. They are pear- 

 shaped, rounded below and 

 pointed above, and 6 to 8 microns 

 long by 3 to 3.5 microns wide 

 (fig. 27) . Two short flagella, 5 

 to 8 microns long, are fastened 

 a little below the middle of the 

 swarm spore. After a time the 

 swarm spores come to rest and infect the host plant, producing 

 roundish protoplasmic bodies, which displace the host cell proto- 

 plasm. This protoplasmic mass contains an orange pigment. It 

 develops and grows in the infected region, finally dividing into 

 many cells. After a second division these cells produce a thick 

 yellow membrane. These bodies are the sporangia of the para- 

 site (fig. 27). They are usually roundish, 20 to 25 microns in 



Woroninella psophocarpi Rac. a, 

 cross section of gall from leaf, 

 showing production of spo- 

 rangia (X 80) ; 6, sporangia 

 (X 325) ; c, zoospores (X 326). 



