Effect of Synthetic Nano-Calcium Borate as an Alternative Boron Fertilizer on the Growth and Boron Utilization of Sunflower Plant

Abstract

ABSTRACT Boron (B) uptake by plants is not always related to the availability of B in the soil. Since B is not mobile in the phloem, conditions such as drought, irregular irrigation, high relative humidity and salinity adversely affect plant B uptake and transport. Thus, new strategies should be developed to improve the transport of B in plants. In this study, greenhouse experiment was conducted to examine the effects of calcium borate nanoparticles (Nano-B) on the B and Ca concentrations of sunflower plants. Nano-B have been synthesized by a method via co-precipitation and characterized by X-ray diffraction (XRD) and Scanning electron microscopy (SEM). The effects of Nano-B, disodium octaborate tetrahydrate (DOT) and colemanite on growth and B uptake of sunflower plant grown in B-deficient acidic and alkaline soils were investigated in greenhouse conditions. Boron was applied at 5 mg kg−1 level. Total B and calcium concentrations were determined separately in young leaf, old leaf and stem. According to the results, there is no difference between B sources and control in terms of fresh and dry weight of the plants. However, all B sources increased the young and old leaf B concentrations of the plant compared to the control. Nano-B treatment was prominent in terms of B concentrations on the old leaves in alkaline soil and on stem in acidic soil. It has been concluded that Nano-B can be an alternative B source and it is necessary to test it in different plants under different growing conditions.