five days the plant was practically dead. Examination of wilting 

 plants showed healthy tojis, hut further search revealed hrown sunken 

 lesions at the crown, which grew rapidly until the stem was girdled 

 and death resulted. A scanty white mycelium was generally present 

 in these areas spreading down along the roots for some distance, 

 rotting and killing them, as well as out over the surface of the ground, 

 attacking weeds or other plants with which it came in contact. At 

 the base of the diseased plant, there was in most cases an abundant 

 production of the so-called sclerotia or fruiting bodies, yellow to 

 dark brown, nearly spherical bodies, of about the size of mustard seed. 

 Sclerotia from peppers produced typical cases of red rot of the leaf- 

 sheath when transferred to cane. 



All four varieties of the second planting were attacked and to 

 about tlie same degree. The loss was greatest in the lower ends of 

 the rows where there was possi])ly more moisture, although plants 

 in all parts of the field were lost. About three per cent of the plants 

 were killed. 



Leaf Spot {Cercosjyora capsici H. & W.) — This leaf spot was most 

 abundant and was collected or observed in numerous localities. The 

 determination is provisional. The spots were circular, varying in 

 size from a sixteenth to luilf an inch in diameter and were often 

 very numerous. Their appearance was the same on both sides of the 

 leaf, not raised, but rather slightly sunken with definite margins. 

 The color was a dark dull lirown with dirty white center and a sur- 

 rovinding faint halo of yellow. Centers of old spots often broke out 

 in-egularly. All varieties were very subject to attack. Older and 

 lower leaves were first infected, turned yellow, and dropped. At 

 times no further damage occurred, but quite often nearly complete 

 defoliation resulted. 



This disease was readily controlled by Bordeaux mixture. No 

 spotting occurred on sprayed rows. 



Root Knot (Heterodero radicicola [Greef] Mill.) — Peppers are 

 very much subject to root-knot and serious damage often results. 

 Tlic trouble is prevalent in manV parts of tlie Island. See under 

 tomato. 



Potato {Salanum fuherosmn). 



Potatoes do not tlirive, at least in the lowlands, and it is extremely 

 doubtful whether any results can be hoped for in any part of tlie 

 Island. A root rot has been reported (1), and the opinion is there 

 given that the disease will prevent the growing of potatoes in Porto 

 Rico. The fungus concerned was not determined. 



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