Abstract
A pot experiment was made to determine the effect of phosphate application upon the infection of rice seedlings by blast fungus, Piricularia oryzae.
The phosphate deficiency in the soil made the rice plant susceptible to rice-blast. But, the excess of phosphate over the necessary quantity for growth gave no protective effect from riceblast. So that the application of phosphatic fertilizer in the soil is effective to the protection from rice-blast in the phosphate deficient soil. but not effective in the phosphate abundant soil, The influence of phosphate deficiency of rice plant on the infection of rice-blast was intensified with the large supplies of nitrogen. As it is known that the phosphate unavailable under low temperature becomes available for plants with the increase of temperature in the field especially in the paddy field, the appication of phosphatic fertilizer acts effectively for the control of the said disease, under the lower temperature rather than under the higher temperature.
