354 Kharak Singh. — Development of Root System of Wheat. 
Watering from below . — Two small earthenware pots — in. x 2 in. 
each with a hole at the bottom — were placed in each big pot with their tops 
level with the surface of the soil, so that they were equidistant from the 
centre of the big pot. When water was poured into these small pots it 
passed into the soil without disturbing the surface. 
Washing. — The method of washing the roots was the same as described 
by Brenchley and Jackson. 1 They were washed on May 26, June 15, and 
July 18. The dry weights of roots and shoots are given in Table I, and 
the photograph of the second lot (June 15) is given in Fig. 2. 
Table I shows the relative condition of the plants 35, 55, and 88 
days old in all the ten pots. After thirty-five days the plants watered from 
below could be arranged in the following order of development, Nos. 9, 1, 
3, 7, and 5, and those watered from above, Nos. 10, 2, 4, 8, and 6. The roots 
in Nos. 9 and 10 reached the zone of manure through the layer of sand ; in 
Nos. 1 and 2 they spread well in the heavy soil, but remained near the 
surface. In the lighter soil they penetrated deeper. In the brick-powder 
the growth was very poor. Comparing the two methods of watering — 
other conditions being similar — all the plants watered from below were 
ahead of those watered from above. The ratios between the roots of plants 
watered in different ways in the same soil show that at this stage the 
difference is well marked in lighter soils, and it becomes progressively less 
so in passing from the lighter to the heavier soil. 
After fifty-five days the plants watered from below could be arranged in 
the order Nos. 9, 3, 1, 7, and 5, and those watered from above Nos. 10, 2, 4, 
8, and 6. At this stage the previous order has changed and the plant No. 3 
in the soil with 25 per cent, sand has gone ahead of the plant No. 1 in the 
heavy soil. The plants in all the soils watered from below are still in 
a better condition than those watered from above, but the difference is more 
marked in the heavier soil than in the lighter one ( vide curve, Fig. 1). 
After eighty-eight days the plants in the pots 9, 7, and 3 were observed 
to have turned pale. On washing it was found that the roots had curled 
round and round in thick layers at the bottom of the pots. Moreover, the 
colour of the roots was found to have turned yellow, possibly on account of 
excessive heat. The relative condition of the roots was the same as in the 
early stage ; but the difference in those watered from below and from above 
was still more marked in the heavier soil than in the lighter one (vide curve, 
Fig. 1, roots). The growth of the plants Nos. 9, 7, and 3 seemed to have 
suffered a good deal as compared with that of the plants Nos. 10, 8, and 4. 
The rate of growth of these plants had become slower than that in the case 
of corresponding plants watered from above. After a certain stage in 
growth these plants appear to have suffered, probably for want of space. 
1 Brenchley, W. E., and Jackson, V. G. (3921) : Root Development in Barley and Wheat under 
Different Conditions of Growth. Ann. Bot., xxxv, p. 535. 
