256 



FUNDAMENTALS OF FRUIT PRODUCTION 



Table 12. — Changes in Water Content of Fruit Buds of Several Varieties 



OF Plums 

 (Arranged from Straushaugh^^^) 



freeze except at temperatures ranging to — 78°C. If a plant tissue con- 

 tains enough adsorbed water, it presumably can withstand any winter 

 temperature. Its free water freezes, but there is enough water which is 

 not readily frozen to maintain the hfe of the protoplasm. 



It seems paradoxical that tender plant tissues usually contain more 

 water than those which are hardier. In fact Johnston found the ratio 

 of water content to dry weight of fruit buds a fairly good index of the 

 relative hardiness of certain peach varieties and similar observations have 

 been made by many other investigators. However, it is shown presently 

 that the development of the water-retaining capacity follows as a reaction 

 to a diminished water supply. Hence, there is a direct relation between 



