EXPEKIMENTS ON THE DECAY OF FLORIDA ORANGES. 21 



ruptures.' The position and tension of the orange rind is a resultant 

 of the interaction between the internal pressure existing in the fruit 

 and the resistance of the rind and atmospheric pressure outside. 



MELANOSE AND AMMONIATION AS RELATED TO THE OCCURRENCE OF 



DECAY. 



As intimated, a rather striking constancy was noticeable in the 

 prevalence of melanose and ammoniation in groves where many 

 fruits were decaying both on the ground and on the trees. It was 

 also noticed that the unusually high percentage of decay of oranges 

 in transit during late November and the month of December was 

 confined almost wholly to those sections of Florida in which the 

 fruits were affected with melanose and ammoniation. In other 

 words, the only sections of the State in which rot was not heavy 

 were the few in which the oranges were neither melanosed nor am- 

 moniated. 



AVhether it is possible to introduce some factors which would 

 prevent such a wholesale dropping and decay in the groves can not 

 be definitely stated at present, but the question is important enough 

 to merit some very careful study. In a detailed study of the factors 

 in picking and packing fruit which contribute to decay in transit, 

 valuable and suggestive results have been obtained by the Office of 

 Field Investigations in Pomology of the Bureau of Plant Industry. 

 It was demonstrated beyond a doubt that by the older and more 

 careless methods of picking and handling the fruit a considerable 

 amount of decay was induced by injuring the rinds in various ways. 

 But the difference between the decay ordinarily due to such careless 

 handling and that which occurred last year in the oranges from most 

 of the State is very evident and is quite large. A number of carefully 

 run packing houses located in regions where melanose and ammonia- 

 tion were prevalent sustained heavy losses from rot in transit in spite 

 of the additional care taken to avoid the trouble. On the other hand, 

 some packing houses doing business in sections free from melanose 

 and ammoniation experienced but little more than the ordinary 

 amount of rot in transit. In view of such results obtained in the 

 uncommon years, it seems advisable to continue the study of the 

 decay of oranges in transit and to pay special attention to factors 

 in the groves that may be related to the occurrence of such extraor- 

 dinary seasons as the one just past. 



The unusually high percentage of decay in severely melanosed 

 and ammoniated groves, as well as the enormous loss in transit from 

 such groves when compared with results obtained in groves free from 

 both of these diseases, indicates either that melanose and ammo- 

 niation on oranges predispose them to rot or else that the conditions 



[Cir. 124] 



