Protein Hydrolysis and Nitrogen Transfer During Germination of Maize Seeds at Various Temperatures

Changes in ethanol-soluble and insoluble nitiogen contents of maize endosperm from seeds germinated in darkness at 10 to 50°C for 50 h were measured to study the effect of temperature on nitrogen solubilization. Nitrogen content of the embryo was also measured to determine the extent of translocation of organic nitrogen during germination. The parameters examined showed maxima at 30 to 35°C which correlated well with the effect of temperature on the germination of seeds and on the protease activity in the endosperm. At higher temperatures, (40–50°C), a major portion of the nitrogen lost from the endosperm wa s leached out to the medium. When the seeds were soaked at different temperatures before sowing, soaking at optimum temperature (30–35°C) supported maximum growth of the seedling and ethanol soluble and insoluble nitrogen content and nitrate reductase activity in the primary leaves. These experiments demonstrate a correlated effect of temperature on seed germination, protease activity and nitrogen solubilization in the endosperm and its translocation to the embryo.