Huimin Feng,  Bin Li, Yang Zhi, Jingguang Chen, Ran Li, Xiudong Xia, Guohua Xu, Xiaorong Fan

Plant Cell Reports; August 2017, Volume 36, Issue 8, pp 1287–1296

Key message

Overexpression ofOsNRT2.3bin rice can increase Pi uptake and accumulation through advanced root system, enhancedOsPTandOsPHRgenes expression, and the phloem pH homeostasis.

Abstract

Nitrogen (N) and phosphorus (P) are two essential macronutrients for plants. Overexpression of the rice nitrate transporter, OsNRT2.3b, can improve rice grain yield and nitrogen use efficiency (NUE). Here, OsNRT2.3b overexpression resulted in increased grain yield, straw yield, and grain:straw ratio, accompanied by increased P concentrations in the leaf blade, leaf sheath, culm, and unfilled rice hulls. Overexpression of OsNRT2.3b significantly increased ³³Pi uptake compared with WT under 300-μM Pi but not 10-μM Pi condition in 24 h. Moreover, the OsNRT2.3b-overexpressing rice lines showed increased root and shoot biomass, root:shoot ratio, total root length root surface area and N, P accumulation under 300- and 10-μM P_i supply in hydroponic solution. The levels of OsPT2, OsPT8, and OsPHR2 expression in roots and of OsPT1 and OsPHR2 in shoots were upregulated in OsNRT2.3b-overexpressing rice. These results indicated that OsNRT2.3b overexpression can improve rice P uptake and accumulation, partially through the advanced root system, enhanced gene expression, and the phloem pH regulation function.

See https://link.springer.com/article/10.1007/s00299-017-2153-9