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

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. [ABSTRACT FROM AUTHOR]