Effects of selenium fertilizer on grain yield, Se uptake and distribution in common buckwheat (Fagopyrum esculentum Moench)

Selenium (Se) is a significant trace element for human and livestock animals because of its physiological functions. Se in plants, especially in the crop plants, is treated as a critical dietary source. The effects of foliar spray together with soil application of Se on Se uptake, distribution in common buckwheat (Fagopyrum esculentum M.) plants were discussed in this study. The results showed that both foliar spray and soil application of Se increased Se uptake in common buckwheat significantly (P < 0.05). The highest Se content was observed in leaves (113.37-690.75 μg/kg), followed by roots (28.98-283.78 μg/kg), grains (26.49-135.89 μg/kg) and stems (23.19-86.80 μg/kg). Se content in grains had the highest correlation coefficient (0.827 and 0.845) with soil Se application treatments. Grain yield of F1 (5 g Se/ha for foliar spray) was 3.65% and 10.25% higher than that of F0 (0 g Se/ha for foliar spray) in two study years, respectively. Under soil Se application conditions, mean grain yields fluctuated from 2890.5-3058.6 kg/ha, 2966.4-3352.8 kg/ha in 2012/2013, respectively. These results indicated a significant interaction effect of foliar spray Se and soil Se application on Se accumulation in common buckwheat. Appropriate Se application might improve common buckwheat grain yield.