612 The Philippine Journal of Science 1923 



Since writing the foregoing account I have been able to obtain 

 an English translation of the Japanese article "On the patho- 

 genic nature of Nishida's anthracnose fungus of citrus," by Dr. 

 Takeo Hemmi.(6) 



Hemmi, working with potted plants, carried on five experi- 

 ments, using an inoculum of Gloeosporium spores in sterile water 

 obtained from cultures from herbarium material of Nishida's 

 fallen-leaf disease. In the first experiment, this inoculum placed 

 on the leaves of Unshiu orange, navel orange, bitter orange, and 

 pummelo resulted negatively in all cases. There is no mention 

 of bell jars or moisture chambers in this experiment and appa- 

 rently the inoculations were carried on in the open air. 



In the second experiment, using the same inoculum, leaves 

 of a potted plant of the Unshiu orange were inoculated ; leaves 

 of a potted plant of the sour orange (Citrus aurantium presuma- 

 bly) were similarly inoculated and both plants placed under bell 

 jars and extremely moist conditions obtained with damp filter 

 paper. Two days after the inoculation the bell jars were re- 

 moved. The sour orange tree remained negative during twelve 

 days after inoculation, but three leaves on the Unshiu orange 

 tree turned brown, the leaves dropped and Gloeosporium acervuli 

 appeared in a few days. 



The third experiment consisted of the inoculation of the same 

 material onto leaves of potted plants of the Unshiu orange and 

 navel orange; bell jars and moist filter paper were maintained 

 around the plants for three days after the inoculation and the 

 plants were then restored to the normal air of the room. After 

 twelve and thirteen days, spreading brown spots appeared on 

 the leaves of the Unshiu orange and the leaves soon fell to the 

 ground. Gloeosporium acervuli formed on the fallen leaves. 

 Un inoculated leaves on the same plant remained healthy and 

 did not fall from the tree. In none of the inoculations were 

 artificial punctures or other injuries given to the leaves. No 

 changes whatsoever occurred on. the inoculated leaves of the 

 navel orange. 



In the fourth experiment, with similar methods, inoculations 

 were made on leaves of a sour orange tree and on leaves of a 

 pummelo. All leaves remained negative with the exception of 

 one leaf of the sour orange which formed the typical spreading 

 brown spot and fell to the ground. Doctor Hemmi was of the 

 opinion that this positive result occurred at a naturally occur- 

 ring wound. 



