1 under different nitrogen concentration

The NH4 + and NO3 ? are N sources available for plant nutrition in most soils. The NH4+ role in plant nutrition has most likely been underestimated. This study provides basic information on the expression of OsAMT11 that is needed in understanding factors contributing to upland rice Nitrogen Use Efficiency (NUE) at the molecular level. The objective of this studies is to evaluate OsAMT11 expression on landraces with different NUE under different nitrogen level. To further understand the molecular basis of responsiveness of these two contrasting upland rice landraces to different N inputs at the N uptake level, a laboratory experiment was conducted to study how members of ammonium transporter gene family respond to different nitrogen conditions. Two upland varieties, Landrace III (high Nitrogen Use Efficiency) and Landrace I (low Nitrogen Use Efficiency) were grown in 4 nitrogen levels (0.05mM NH4NO3, 0.1mM NH4NO3, 1mM NH4NO3 and 2mM NH4NO3). Quantitative RT-PCR was used to study the expression of patterns of rice OsAMT11 genes. Results from this study showed that Landrace III has relatively higher expression of OsAMT11 compared to Landrace I for all treatments. Expression of OsAMT11 is clearly up-regulated in response to low-nitrogen treatment. Expression levels of OsAMT11 in high-NUE upland rice landrace was higher compared to low-NUE upland rice landrace. These results suggested, expression of OsAMT11 had certain degree of influenced in NUE of upland rice landraces