Effects of two substrates at different phosphorus levels on morphology and physiology of Dianthus barbatus Linn

Dianthus barbatus linn. is widely used in gardens, mainly as flower beds and flower borders. The effects of different gradients of P on the growth and root morphology of Dianthus barbatus were studied to explore its morphological and physiological responses and adaptive strategies. Hence, this study provides a theoretical basis and practical guidance for D. barbatus production. Two soil substrates, namely loess and vegetable soil, and five phosphorus concentration gradients were set; no phosphorus application was used as the control. The morphology and physiology of D. barbatus were also investigated. Low-to-medium- and low-phosphorus treatments promoted the growth of D. barbatus in the above and underground parts of the plants grown on both substrates. Chlorophyll content, flower quantity, and acid phosphatase activity in the rhizosphere soil were significantly increased in the H1 and H2 treatments of loess and in the C4 treatment of vegetable soil. Thus, D. barbatus seems to reduce the damage caused by phosphorus stress by increasing chlorophyll content and root acid phosphatase activity. The latter was significantly higher in vegetable soil than in loess. Vegetable soil was more conducive to D. barbatus growth than loess.