Special expression of alanine-aminotransferase1 (OsAlaAT1) improves nitrogen utilization in wheat

Abstract

Nitrogen is an essential macronutrient for crop development and growth. However, nitrogen-based fertilizer application not only increases the cost of crop production systems, but also causes serious environmental pollution and low nitrogen use efficiency (NUE) in cereal crops. To enhance the NUE of wheat (Triticum aestivum L.), the transgenic approach was used to create a new variety. In this study, the rice (Oryza sativa L.) alanine-aminotransferase1 (OsAlaAT1), an important nitrogen assimilation enzyme affecting the NUE of plants, was transformed into wheat under the control of TaAnt1 promoter. Special expression of OsAlaAT1 enhanced the height and 1000-kernel weight of wheat. It also affected the expression level of starch synthesis-related genes in seeds at 10 and 15 days after pollination. Independent lines expressing OsAlaAT1 exhibited higher grain production than wild-type plants under high-nitrogen and, especially, low-nitrogen supplementation. Our results suggest that OsAlaAT1 improves the NUE of wheat.