Assaying the efficiency of sulfate, chelate and zinc nanoparticle fertilizers in green bean grown in alkaline soil

The excessive fertilizer application is a recurring problem in agriculture as it not only harms the soil texture but also diminishes the micronutrient availability i.e., zinc (Zn). Zn is an essential element for crop production and quality, and is also indispensable for human diet. Zn deficiency is a common problem in alkaline soils. This study aims to assess the efficiency of three different Zn fertilizers in Phaseolus vulgaris plants, grown in an alkaline soil. P. vulgaris plants were grown in an experimental greenhouse under four different treatments: control (no Zn fertilization), ZnSO4, the chelate diethylenetriaminepentaacetic acid (DTPA-Zn), and Zn nanoparticles (NfsZnO). Each Zn source was applied at three different doses (0, 25, 50, 100 mg kg(-1)). Parameters related to biomass, photosynthetic pigments, and Zn accumulation were analyzed. Zn sources enhanced bean pod growth and yield. Furthermore, the three Zn sources increased Zn accumulation in all plant organs, except in leaves. Whereas, plants supplied with 100 mg kg(-1) of DTPA-Zn and 25 mg kg(-1) of NfsZnO accumulated the highest bean Zn concentration. Generally, plants supplied with DTPA-Zn and NfsZnO showed the highest Zn content values. Besides, Zn sources enhanced the values of Zn efficiency parameters in a dose-dependent manner. According to the results, the three Zn fertilizers were effective to increase the parameters analyzed in P. vulgaris. However, DTPA-Zn and NfsZnO were more effective to enhance yield and bean Zn content, and thus can be useful for bean cultivation in alkaline soils.