Activities of Carbon and Nitrogen Metabolism Enzymes of Sorghum (Sorghum bicolor L. Moench) During Seed Development

Abstract

Carbon and nitrogen metabolism pathways are regulated by complex mechanisms in order to optimize growth and development of plants and play a major role in determining the amount of protein stored in cereal grains. This study was conducted to contribute to determine the roles of certain key enzymes of carbon and nitrogen metabolism in developing sorghum seeds. Sorghum bicolor (L.) Moench was grown in a growth chamber. Seeds were harvested at various stages of development and used to the analysis of certain key enzymes of carbon and nitrogen metabolism. The results were subjected to stastistical analysis using one-way analysis of variance (ANOVA) followed by the Tukey test. The results showed that during the seed development the highest activities of glutamine synthetase, glutamate dehydrogenase, phosphoenolpyruvate carboxylase, malate dehydrogenase, isocitrate dehydrogenase, and aspartate aminotransferase were detected at the time of maximum seed filling stages (15-20 DAP). Hence, higher activities of these enzymes at the time of maximum seed-filling stages could be effectively linked to amino acids synthesis and therefore the deposition of protein reserves.