42 Journal of Agricultural Research voi. x. no. i 



absorption of water by the milo from the soil and its translocation to 

 leaves was proceeding more rapidly in proportion to the loss of water 

 from the plant than in the case of either corn or kafir. The fact that 

 the leaves of milo seldom wilted during the day also indicated that fact. 

 The wilting of the leaves of milo in contrast to either the corn or kafir 

 usually could not be observed until much later in the day. The increase 

 in the rate of loss of leaf water in the milo from i to 3 p. m. would indicate 

 that the rate of absorption of water from the soil during that period 

 was less than the loss by evaporation from the leaves. 



VARIATION OF THE DRY MATTER 



The amount of dry matter in the leaves of milo was at all times greater 

 than in the leaves of corn or kafir of the same age. If we take the average 

 weight of a square meter of corn leaf as i , the average weight of an equal 

 area of leaf would be 1.08 for kafir and 1.16 for milo. These differences 

 in weight could be due either to the more compact arrangement of the 

 cells or to a difference in the thickness of the leaves of the three plants 

 or to both of these factors. 



The average difference between the maximum and minimum amount 

 of dry matter in the leaves during the day from 7 a. m. to 7 p. m. was 

 4 gm. for com, 4.8 gm. for kafir, and 8.0 gm. for milo. Table V shows 

 the rate of increase in dry matter for corn, kafir, and milo in grams 

 per square meter of leaf for each of the 2 -hour periods during the day, 

 from 7 a. m. to 5 p. m. From 7 to 9 a. m. the rate of increase in dry 

 matter for each square meter of leaf was 2.2 gm. for corn, 1.7 gm. for 

 kafir, and 1.3 gm. for milo. From 9 to 11 a. m. the increase of dry 

 matter on the same basis was i.i, 1.2, and 1.5 gm. for corn, kafir, and 

 milo, respectively, while from 11 a. m. to i p. m. the increase was 0.8 

 gm. for corn, 0.7 gm. for kafir, and 2.2 gm. for milo. From i to 3 p. m. 

 the rate of increase was 0.7 gm. for corn, 1.3 gm. for kafir, and 2 gm. for 

 milo, while from 3 to 5 p. m. the increase of dry matter was 0.8, 0.7, 

 and 0.8 gm. per square meter of leaf surface, respectively, for corn, 

 kafir, and milo. The greatest rate of increase of dry matter in the corn 

 leaves occurred from 7 to 9 a. m. During the next 2 -hour period the 

 rate had fallen one-half. The rate continued to decrease until 3 p. m., 

 when there was a slight increase. The rate of increase of dry matter 

 in the leaves of milo rose gradually from 7 a. m. until i p. m. and then 

 remained constant until 3 p. m., when it began to decrease. The results 

 with the leaves of kafir were not so marked. There was a noticeable 

 falling of the rate of increase of dry matter from 9 a. m. to i p. m., and 

 then a slight increase in the rate till 3 p. m. 



