July, 1921] BALL — RELATION OF BOTANY TO HUMAN WELFARE 
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of the resulting plant, and the determining of the conditions under which 
plants may escape or resist the attacks of soil-infecting and other fungi. 
The study of water relations is of very high importance. Studies in 
the water requirements of several important crop plants, as revealed through 
transpiration measurements, have been conducted in recent years by Briggs 
and Shantz and by Montgomery and Kiesselbach, but these are only a 
good beginning compared with the research that is needed. 
Investigation of the duty of water in irrigation is much more a problem 
for the plant physiologist than for the irrigation engineer. The first phase 
is the determination of the effect of applying water, at different times and 
in varying quantities, on the comparative and actual development of the 
roots, vegetation, and fruits of crop plants. The second phase is the possi- 
bility of increasing total crop production by making the present supply of 
irrigation water cover much more than the present number of acres. It 
is conceivable that reducing the quantity of water by one half might re- 
duce acre production by only two or three tenths and permit irrigation 
of twice the present acreage. Two acres of irrigated wheat yielding 35 
bushels each may be more valuable to humanity and just as profitable to 
the grower as one acre yielding 50 bushels. It is not unthinkable that one 
day we shall see governments exercising the right of eminent domain to 
accomplish such results through reducing existing water rights. 
Studies in plant nutrition long have been known to be of fundamental 
importance. The chief difficulty in such research has been to control ex- 
perimental conditions and at the same time to approximate natural condi- 
tions. Solution cultures permit controlled conditions but give only sugges- 
tive results. Fertilizer plats approximate natural environment, but are 
conducive to confusing interpretations. The gulf between the two may 
be bridged by continued refinement of method and interpretation. 
Studies in the physiology of the development of seeds and fruits in 
our major food plants, such as the cereals, are of the utmost concern. The 
period of vegetative growth may be prolonged over several months, but 
usually the formation and maturing of seeds takes place in the brief period 
of two to four weeks. Obviously, this is an important and perhaps even 
critical period in the life of the plant, from the economic standpoint. Physi- 
ology can help to show what tillage, or irrigation, or fertilizer practices dur- 
ing or just previous to this period, will influence directly the quantity and 
quality of the product. 
Some preliminary studies in the deposit of protein and starch in de- 
veloping wheat kernels were made several years ago in the state of Washing- 
ton by Dr. Thatcher and his associates. Dr. Harlan, of the Office of Cereal 
Investigations, U. S. Department of Agriculture, is now publishing a series 
of papers dealing with some phases of the development of the barley kernel. 
Such studies are but the forerunners of what is required as a foundation for 
a better knowledge of the behavior of our crop plants at this critical period 
in their development. 
