Potassium utilization in EdHP1 (H⁺-pyrophosphatase) transgenic wheat

With intensive land farming, soil potassium deficiency has become increasingly serious, limiting sustainable agricultural development. In this study, the differences between EdHP1 (H⁺-pyrophosphatase) transgenic and wild wheat were investigated in terms of potassium absorption and utilization, rhizosphere soil potassium dynamic and soil enzyme activities. The research aimed to determine the potentials of transgenic technologies in promoting wheat potassium absorption and utilization. The results showed that available K in rhizosphere of transgenic wheat was significantly lower than that of wild wheat at different K-levels. Available K in rhizosphere of transgenic wheat were 8.30% (30 d), 15.02% (60 d) and 12.53% (75 d) below those of wild wheat for K1-level (KCl application rate of 186 kg·hm^-2). For transgenic wheat high potassium absorption, available K is transported from non-rhizosphere to rhizosphere soil. Under K0 (no KCl), K1 and K2 (KCl application rate of 805 kg·hm^-2) treatments, biomass K use efficiencies (KUI-B) were 22.39%, 136.21% and 14.03%, respectively. Also while shoot K contents were 225.97%, 18.77% and 17.28%, root cation exchange capacities (CEC) were 55.19%, 33.16% and 30.44%, respectively. Rhizosphere soil catalase and urease activities of transgenic wheat were significantly higher than those of wild wheat at different K-levels. Thus transgenic technology improved root CEC and created good rhizosphere environment for efficient wheat potassium absorption and utilization.