水稲の胡麻葉枯病罹病に関する栄養生理的研究 (予報) : V. 鉄加用が水稻の生育及び胡麻葉枯病罹病に及ぼす影響

抄録

We have made a study about the influence of iron (Fe^··), manganese, potassium and hydrogen sulphide, added to the culture solution, upon the growth of the plant and susceptibility to Helminthosporium leaf spot. The result of the experiment is as follows : (1) Addition of a large amount of iron (Fe^··) brought injurious effect upon the growth of the root and caused root rot, resulting in decreased transpiration. But the addition of manganese, on the contrary, gave favorable effect upon the foot growth, leading to increaseed transpiration. (2) Both the percentage content of MnO and the ratio of MnO to FeO of the leaf blade were diminished either with the increasing supply of iron or by the addition of hydrogen sulphide. (3) There was a high negative correlation between the susceptibility of the rice plant to the disease and the MnO/FeO ratio of the leaf blade. The yield of the plant was negatively corretated with the degree of root rot, but was possitively correlated with transpiration and with the SiO/N ratio of the leaf blade. No high correlation, however, was seen to exist between the susceptibility and the yield.