Gray Leaf-Spot {I.'<ariopsis griseoJa Sace.) — On the first planting 

 spots due to this fungns were rare, but on the second were fairly 

 al)iindant on the northern varieties. The black Venezuelan remained 

 free. A native variety of the red kidney type was noted, in which 

 the entire planting was spotted to such an extent as to cause a heavy 

 dropping of leaves and consequent weakening of the plants. It is 

 a common disease in native plantings. It can doubtless be controlled 

 ])}■ Bordeaux mixture. 



This disease was characterized by irregular, brownish gray to 

 gray spots on the leaves up to half an inch in diameter. The spots 

 differed from those due to Cercospora in that they were duller in 

 color and lacked the definite red-brown angular margin. The fungus 

 fruited freely in the center of the spots and appeared under a hand 

 lens as numerous erect, rather compact, black clusters of conidio- 

 phores or conidia-bearing threads. 



LeaT Spots (Cercospora spp.) — At least one other type of leaf 

 spot occurred. The one conuuonly found and due to Cercospora 

 cancsccns Ell. & ^lartin was eollected on varieties of Phaseolus vul- 

 garis (common bean), DoUchos lahldh, and Phaseolus lunatus (lima 

 bean). The spots due to this fungus were more or less angular, up 

 to one-fourth indi in diameter, gray with a reddish brown definite 

 margin, and tlieir appearance was the same on both sides of the leaf. 

 A specimen of Cercospora cruenia Sace. collected on bean in Porto 

 Kico is in the herbarium of the New York Botanical Garden. Dinie- 

 riuni grammochs (Kuntze) Gar. is reported on Phaseolus lunatus by 

 Garman (9). 



Powdery ^IiTvDEw (Erysiplir pohjgoni DC?). — A powdery mildew 

 appeared on the leaves of several of the varieties after the crop had 

 lieen gathered and the plants were past maturity. Only unsprayed 

 portions of tlie rows were attacked. It is of very minor importance 

 since only old, unsprayed plants were found subject to it. The 

 determination can be only provisional since the imperfect or Oidinm 

 stage onl.y was found. 



Crown Rot {Fusarium sp.) — A crown rot or damping-otf was 

 noted to a very limited extent attacking the native red variety. 

 Sunken lesions occurred on young plants at the ground level and 

 extended for an inch or two along the stem, accompanied by a scanty 

 production of white mycelium of a Fusarium sp. This was later 

 noted on northern varieties, attacking young plants at various stages 

 up to six inclics in licight, in some cases isolated i)lants only, in 

 others accouiitiiig for several plants in a group or even a doz(>n or 



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