Abstract
Preliminary studies were carried out to examine the effects of iron on the appearance of morphogenetical abnormalities due to an unfavourable low temperature in rice spikelets. 10 ppm of iron was supplied in the nutrient solution by way of Fe·EDTA (chelating agent with iron), Ferric Citrate and Ferric Chloride, the control concentration of iron being 1 ppm supplied with Ferric Citrate. Also a plot of Na·EDTA was provided in order to clarify the influence of EDTA containing the same amount of iron as the control. It was found that iron, given as Fe·EDTA, showed a remarkable inhibitory effect on the appearance of morphogenetical abnormalities and they were totally or partially eliminated in presence of Fe·EDTA even under an unfavourable low temperature, though the other plots did not give any desirable effect. Some discussions were tried on the relationships between the auxin action and iron from the hormonal aspects, but this paper did not offer any reason why the inhibitory effect was brought about by the Fe·EDTA, leaving the detail physiological interpretation to the future investigations. Ineffectiveness of Ferric Citrate and Ferric Chloride was considered to be attributed to the difficulties in the uptake or absorption of them by plants.
