Figure 8.

In vitro assays for radioactive [³³P]Pi directly taken up by nodules in GmPT5 transgenic soybean plants. Transgenic soybean plants inoculated with rhizobia were grown in low-N nutrient solution with low P (5 μm P) or high P (250 μm P) for 50 d before being used in in vitro assays. Three nodules from each transgenic line pretreated by low P or high P for 50 d were immersed in the same ³³P-labeled nutrient solution for a 2-h uptake assay. [³³P]Pi accumulation in nodules was quantified at both low P and high P levels. cpm represent radioactive cpm measured by a liquid scintillation analyzer. CK, Transgenic soybean plants carrying empty vector; FW, fresh weight. There were four biological replicates for each treatment, and bars show means ± se. ns, Not significant at 0.05.