III. 
A CRITICAL STUDY OF THE VARIETAL 
CHARACTERS OF INDIAN WHEATS. 
The influence of the environment on cultivated plants is well 
known and wheat is no exception to the rule. To a greater or less 
extent wheat is grown all over India and consequently the condi- 
tions, as regards climate, soil and moisture, under which the crop 
is cultivated, are very variable. 
The most important conditions influencing the growth of wheat 
in India are :— 
1. The maximum duration of the growth period in each 
tract. 
2. The available soil moisture during that period. 
The duration of the growth period is strictly limited and de- 
pends on the time when the hot weather begins in the spring. This 
varies with the latitude, being earlier in Bombay, the Central Prov- 
inces and Behar, a little later in the United Provinces and still 
later in the Punjab and North-West Frontier Province. As soon 
as the temperature rises above a certain point and the hot winds 
begin to blow, the wheat crop ripens off very quickly and dries up 
if not fully developed by that time. In general the crop may be 
said to ripen under a rapidly ascending temperature. Harvest 
takes place in Bombay and the Central Provinces in February, in 
Behar and Oudh in March and in the Punjab from the last week of 
April totheend of May. Only rapidly maturing wheats are of use in 
India either for purposes of cultivation or use in hybridisation. 
Of more importance than the growth period is the variation 
from year to year in the available moisture. Wheat is grown on 
natural rainfall alone, on excessive canal irrigation as in the canal 
