lOi JOUKNAL OF AGBICULTUEE OF P. E. 



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and underlying rag tissue, which later assumes a pink color, fol- 

 lowed by the brown rotting. The apparent cause in this case is a 

 fungus {Fusarium sp.)- This form has been isolated a consider- 

 able number of times and by inoculation has been found capable 

 of producing the rot. Investigations of this disease have shown 

 that the anthracnose fungus is commonly present as a secondary 

 agent, the rot progressing very slowly until this form enters. 



Occasionally instead of the pink staining in the tissues at the 

 blossom end there will be a black decayed area, which spreads even 

 more slowly than the pink rot. and may remain confined to one 

 section of the fruit only. The fungus in this ease is kno'wai as Al- 

 ternaria citri, and is common, though not serious, in California and 

 Florida. The Fusarium type has been reported only from Porto 

 Rico. 



Infection in the case of both of these fungi occurs probalily in 

 the blossom, or while the fruit is very young. A certain pr'rcen+- 

 age of infected fruit drops immediatel.y, but in the others the fun- 

 gus after a limited development becomes dormant until the fniii 

 approaches maturity, and loses its power of resistance. 



The complete life history of the eausMtive fungi not having been 

 worked out. control measures are somewhat uncertain, but will in 

 the main consist of grove sanitation, the picking up of all dro]>s, 

 and removal of dead wood. 



JUNE DEOP. 



A common phenomenon in commercial groves, and one whicli i-e- 

 suits in heavy losses at times, is the dropping of immature fi'uil. 

 Following the bloom ])eriod there is always m Iicmyv shedding ef 

 the newly fonned fruit, and again in May or June tiiere is very 

 apt to be a second period, when dropping of fruit, by this time from 

 an inch ro two inches in diameter, occurs to a serious extent. A 

 considerable portion of this dropping must be considered nornui!, 

 the tree merely having set more fruit than it is capable of carry- 

 ing through to maturity. If this natural thinning did hot occui'. 

 steps to tlie same end would be necessai'v on tbe |)aT't of the grower. 



However, miu-li of the dropping must be considered abnormal, 

 particularly that occurring during tlie seeond or June period. At 

 this time many of the fallen fruit show irregular, brown, gumming 

 areas on the surface and a brown stain at the blossom end. In the 

 many cultures made of this class of material but one fungus ha- 

 ever been found with any degree of regularity. Collect otrichunt. 



