RosELLE (Hibiscus sahdarijfa) . 



Barrett reported (3) a root rot of this plant, possibly due to 

 bacteria. Not observed in the present investigations. 



Sesame (Sesanium orientale). 



This plant, locally known as "ajonjoli," is commonly subject 

 to a leaf spot attacking particularly the lower leaves, although in- 

 stances have been observed of mature plants which had been prac- 

 tically defoliated. The spots, due to Cercospora Sesami Zimm, are 

 very numerous, small (not over two millimeters in diameter) sub- 

 circular to angular, dull white to gray, with a definite, slightly raised 

 deep brown margin. Sporulating on the upper surface. 



Squash (Cucurbita moschata). 



In so far as observed this crop was free of disease, even when 

 in proximity to other cucurbitaceous plantings, such as cucumbers 

 or melons. Henricksen (5) reports downy mildew as an enemy of 

 the squash. 



Sweet Potato (Ipomoea batatas). 



The sweet potato is one of the most common of the native crops, 

 and while no large plantings are made the total of the innumerable 

 small patches is considerable. As is usual with a crop which is not 

 planted in large or continuous areas, serious diseases seem to be lack- 

 ing. There have been reports received of losses, but in so far as it 

 has been possible to discover from specimens submitted, invsects have 

 been to blame. However, it is known that some at least of the dry 

 rots reported for other countries do exist here, and an effort will 

 be made to find them. 



White Rust (Albugo ipomoeae-panduranae [S.] Swing.) — Only 

 three fungi have been encountered on this host, all leaf parasites. 

 The most common of these was the white rust, which caused indefi- 

 nite spots varying from the size of a pinhead to half an inch or 

 more in diameter. At times whole leaves were deformed and swell- 

 ings produced on stems and petioles. The spots were yellow to brown 

 above, and below showed the white pustules formed by myriads of 

 spores. All of the various types or varieties of sweet potato, both 

 <:'ultivated and wild, have been found subject to attack. 



Le.\p Spot (Phf/Uosticta batatas E. & M.) — In one instance leaf 

 spots due to this fungus were found. The spots were circular to 

 .angular, up to one-quarter inch in diameter and light gray in color 



111 



