抄録
The plants cultured on the field ordinalily were sprayed with 2, 4-D solution on 14. Aug. at the rate of 20 gr or 100 gr per Tan (nearly 0.25 acre), the dose being believed somewhat little for eradicating such vigorously growing plants. After the spray, chemical analyses were made three times (on 19, 26 and 31. Aug.) with regards certain constituents of sprayed plants as well as non-sprayed ones. The main results obtained are shown below. (1) The amount of crude protein as well as pure-protein decreases in leaves, but increased in stems, and total amount of protein increases in sprayed plants which is believed noteworthy in their use as fodder. (2) The reducing sugars, total sugars and soluble non-nitrogenous substance increase in their amounts in sprayed plants (leaves as well as stems). (3) The crude ash contents decrease in leaves, but not in stems. (4) The amount of crude fiber decreases in stems, but never in leaves. (5) The activity of Vitamin C reduces markedly in leaves which is the same as in the previous study. (6) In the present study, it is observed that a kind of injurious insect, Anomala rufpcuprea Mutschulsky assembled to sprayed plants to eat their leaves, 5 day after spraying. This fact deserves attention from various points of view especially from killing plants by 2, 4-D.
