Effects of Drought and Elevated Atmospheric Carbon Dioxide on Seed Nutrition and 15N and 13C Natural Abundance Isotopes in Soybean Under Controlled Environments

Abstract

The objective of the current research was to evaluate the effects of drought and elevated CO 2 on seed production and seed nutrition under controlled conditions in soybean. Soybean plants were subjected to ambient and elevated CO 2 and under irrigated and drought conditions. The results showed that drought or drought with elevated CO 2 resulted in high protein and oleic acid, but low in oil and linoleic and linolenic acids. Significant decrease of sucrose, glucose, and fructose concentrations was noticed, but high content of raffinose and stachyose was observed. Nutrients such as N, P, K, and some micro-nutrients were reduced under drought or drought with normal or elevated C ratio) natural abundance isotopes were also altered under drought or drought with ambient or elevated CO 2 concentrations, reflecting nitrogen and carbon metabolism changes. The current research demonstrated that global climate changes may lead to changes in seed nutrition, and nitrogen and carbon metabolism. Efforts of breeders to select for these traits will sustain food source and food security for humans and livestock as soybean is a major source for protein and oil for human consumption and soymeal for animals.