Effect of nitrogen and phosphorus on alleviation of boron toxicity in Puccinellia tenuiflora under the combined stresses of salt and drought

Abstract

High boron (B) often occurs in saline and arid soils and exerts toxicity to plants. A potting experiment was conducted to examine the effects of nitrogen (N) and phosphorus (P) on alleviating B toxicity in an alkali grass, Puccinellia tenuiflora, in saline and arid soils. As a B-tolerant species, P. tenuiflora grew well in soil with high concentration (300 mg kg−1) of B under the combined stresses of salt and drought. N and P have significantly increased plant biomass and decreased B concentrations in plants by 14.5%–31.4% in the shoot and 22.3%–41.5% in the root, respectively. The results indicate that the addition of fertilizer enforced photosynthesis of plant and decreased K+/Na+ ratio. Our results suggest that N and P can be used to alleviate B toxicity in P. tenuiflora under the combined stresses of salt and drought.