Bulletin Spring‧Summer 2001

Asparagine Synthetase Genes Their Roles in Growth and Development N itrogen plays a critical role in plant growth, as it is required for the synthesis of amino acids, proteins, and DNA. Scientists have also discovered that photosynthesis is closely related to the nitrogen content of leaves. A high nitrogen supply entails a higher rate of photosynthesis, and hence, a faster pace of growth. Some plants such as legumes can obtain their nitrogen from the atmosphere via symbiotic nitrogen fixation, while other plants, including most crops, depend on the availability of nitrogen resources in the soil. Farmers usually try to increase crop yield by applying nitrogen- containing fertilizers to the soil. However this method is not only costly, but also harmful to the environment. Therefore, boosting the efficiency of nitrogen assimilation and utilization in higher plants will have significant economic and environmental benefits.