Seed performance of maize in response to phosphorus application and growth temperature is related to phytate-phosphorus occurrence

Phytate is associated with antinutrient character in seeds; however, it has potential to contribute significantly to seed performance. The objective of this study was to determine the effect of P (10, 26, and 70 mg kg(-1)) and growth temperature (22/16, 27/21, and 33/27 degrees C [day/night]) on seed 1 performance in normal and quality protein maize (Zea mays L.). Seeds of normal and quality protein maize were harvested at three stages (15, 25, and 65 days after Bilking) of development. At each stage, germination capacity and vigor, Phytate-P concentration, and myo-inositol were determined. Normal maize displayed a significantly higher (P < 0.001) phytate-P and inorganic P concentrations compared with quality protein maize, which was associated with significantly better (P < 0.01) seed performance. Myo-inositol was significantly (P < 0.05) higher in quality protein maize compared with normal maize. Phosphorus nutrition enhanced (P < 0.01) seed performance of both genotypes. Increasing growth temperature caused greater accumulation of inorganic P, but it decreased myo-inositol. Seed germination and vigor increased when growth temperature was increased from 22/16 to 27/21 degrees C, but they decreased in response, to high temperatures (33/27 degrees C). The results of this study indicate that P fertilizer enhances maize seed germination and vigor. High myo-inositol concentrations may be used to indicate poor phytate synthesis associated with poor seed performance.