FLORIDA. 91 



ing or other work. The $40,000 appropriated b}' the last legislature 

 for a new station building did not become availal)le until some time 

 after the close of the fiscal year, when work on the new structure 

 was begun. 



The Adams fund projects of the station were all carried forward 

 during the year. Results obtained in connection with studies of 

 diseases of citrus fruits indicate that the scaly-bark disease is due 

 to a fungus and that the malady is aggravated by the wither-ti}) 

 fungus which attacks the diseased portions. Means of control were 

 studied in a private orchard. By producing the disease through 

 inoculation it was shown that the scab attacking the fruit and leave.s 

 of sour orange, satsumas. and grape fruit is due to a fungus. A 

 bacterium accompanying the gumming of citrus trees was studied as a 

 possible cause of the malady. 



In following uj) the i)roject on parasites of the white fly as a 

 means of control, it was found that '2 species of the insect occur and 

 that one of them {Aleyrodes nuhifera) is readily attacked by the 

 yellow fungus. Spraying trees with spores of the yellow and red 

 fungus Avas found effective in destroying the larva\ and the method 

 has already been taken up commercially (PI. Ill, fig. 1). The spores 

 for the sprays were drawn from the laboratory or obtained from 

 affected leaves. 



The studies in plant nutrition with reference to physiological dis- 

 eases, carried on with cassava and citrus fruits, showed that such citrus 

 diseases as die-back, yellow spot, melanose, and frenching are not 

 caused by an organism, but are due to malnutrition. A deep russet- 

 ing of the orange was found due to fertilizers and especially to 

 those furnishing ammonia. 



The j)ineai)ple work in connection with the study of soils and 

 fertilizers in relation to plant growth and develojiment was con- 

 tinued, and a rejjort on the results of analysis of the fruit is about 

 ready for printing. No special effect of any particular fertilizer 

 was observed, but different amounts seemed to affect the composition. 

 Steps liave been taken to study the effect of fertilizer ingredients 

 on citrus fruits. 



The station al^o has in progress a number of lines of work sup- 

 ported by the Hatch fund. The horticultural department studied 

 and largely worked out the embryology of the mango and also made 

 some studies on the preparation of guava jelly. The l)otanical 

 department gave attention to the improvement and selection of let 

 tuce and celery for disease resistance, and also conducted breeding 

 work with the velvet bean to jiroduce a bush form. Other lines of 

 phint improvement carried on li\- lh(> station are cotton breeding for 

 length of stajjle. >iJkiiiess. and naj): breeding a type of corn adapted 

 to the State: introducing and acclimatizing the Lyon bean brought 



