Effects of amino acids selenium fertilizer on selenium    concentration of pear

【Objectives】The effects of different amino acid selenium (AAS) fertilizer application methods were studied on the content of selenium in Huasu pear, so as to provide theoretical basis for reasonable application of amino acid selenium and se-enriched pear production. 【Methods】Spraying and soil application methods were used in the experiment, and four application rates of 30 mL(900 mg/plant), 60 mL(1800 mg/plant), 90 mL(2700 mg/plant) and 120 mL(3600 mg/plant) were set for soil application, and four dilution folds of 300(150.0 mg/plant)、 400(112.5 mg/plant)、 600(75.0 mg/plant) and 1000(45.0 mg/plant) were set for spraying. Spraying was madeevery fifteen daysfrom full-bloom stage to fifteen days before fruit ripeningwith seven sprays intotal. For soil use, the schedualed fertilizer was dissolved in water and evenly loaded into the 4 holes (20 cm20 cm20 cm) 30 cm from the trunk at full-blom stage.Fruits and leaves were sampled respectively at 15, 30, 45, 60, 75 and 90 days after blossom. Fruits were dissected into peel, flesh and core. Selenium contents in different parts of pear fruits and leaves were determined with Atom Absorption Spectrometry.【Results】1) AAS could significantly enhance selenium contents of pear fruits and leaves by both spraying and soil application. 2) The highest selenium contents of fruits and leaves were at the beginning of the development in the treatments of spraying, and the trends of all the analyzed parts were different. With soil application, the selenium contents of fruits and leaves are increased gradually and reached the highest at the harvest. 3) AAS application stimulates the selenium absorption of fruit, and the period from thirty to forty days after the floweringis critical for selenium absorption. 4) Selenium content is higher in leaves than in flesh, no matter fertilization or not. The selenium contents of fruit peel, flesh and core are affected by spraying, but not by soil application. 5) When the spraying amount was low than 2700 mg/plant, selenium contents of pear flesh and leaves are positively correlated with the spraying amount, the contents will decreaseover 2700 mg/plant.【Conclusions】Amino acids selenium fertilization impacts the selenium concentration of pear. Compared with soil application, spraying is more effective in stimulating Se-absorption, Se-accumulation and Se-utilization. The proper spray amount of amino acids selenium fertilizer is not excessive of 2700 mg/plant.