It is to the prevention of this transpiration that much
investigation must be given by future students of dry-farming.
Transpiration
As water evaporates through the breathing-pores from the leaves it
necessarily follows that a demand is made upon the lower portions of
the plant for more water. The effect of the loss of water is felt
throughout the whole plant and is, undoubtedly, one of the chief
causes of the absorption of water from the soil. As evaporation is
diminished the amount of water that enters the plants is also
diminished. Yet transpiration appears to be a process wholly
necessary for plant life. The question is, simply, to what extent it
may be diminished without injuring plant growth. Many students
believe that the carbon assimilation of the plant, which is
fundamentally important in plant growth, cannot be continued unless
there is a steady stream of water passing through the plant and then
evaporating from the leaves.
Of one thing we are fairly sure: if the upward stream of water is
wholly stopped for even a few hours, the plant is likely to be so
severely injured as to be greatly handicapped in its future growth.
Pages:
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174