黄腐酸对肥料磷有效性及苹果砧木幼苗磷吸收利用的影响

Effect of Fulvic Acid on Phosphorus Availability and Phosphorus Absorption and Utilization of Apple Stock Seedlings

[目的]探索在不同黄腐酸水平下苹果砧木M9-T337幼苗的生物量、根系形态、根系活力及其对根际土壤酶活性、速效磷含量与磷利用率的影响,为促进苹果砧木的生长及提高磷利用率提供科学依据。[方法]以1年生M9-T337幼苗为材料,采用土壤盆栽试验研究不同黄腐酸水平下苹果砧木吸收利用磷的能力。[结果]不同黄腐酸水平显著影响了苹果砧木M9-T337的根系总长度、根系总面积、根尖数和根系活力,随黄腐酸水平升高均呈先升高后降低的趋势;根际土壤的酸性磷酸酶活性随黄腐酸水平升高呈先升高后降低的趋势,在H2处理时达到最高,CK最低;根际土壤速效磷含量变化趋势与之相同。M9-T337的生物量、磷积累量与磷利用率与其根系活力、根系形态及根际土壤酸性磷酸酶活性对黄腐酸水平的响应规律一致。[结论]施用适量黄腐酸(100 kg/hm2)可显著促进苹果砧木M9-T337根系生长,提高根系活力,增强根际土壤酸性磷酸酶活性,从而提高幼苗根系对磷的吸收与利用。

[ Objective] To explore the biomass,root morphology and root activity of M9-T337 seedlings under different levels of fulvic acidand its effects on enzyme activity in rhizosphere soil, content of available phosphorus and utilization of phosphorus, ic basis for promoting the growth of apple rootstock seedlings and improving the utilization of phosus absorption and utilization of M9-T337 under different levels of fulvic acid was studied by soil pot experiment lings as material. [Result] The total root length,total root area,root tip number and root activity of M9-T337 were significantly afected by different levels of fulvic acid. The acid phosphatase activity in rhizosphere soil increased first and then decreased with the increase of the level of fulvic acid. The activity of acid phosphatase in rhizosphere soil increased first and then decreased with the level of fulvic acid, whichreached the highest in H2 treatment and lowest in CK treatment, the trend of available phosphorus content was the same as that. Biomass,phosphorus accumulation and phosphorus utilization rate of M9-T337 were consistent with the responses of root activity,root morphology and acid phosphatase activity of rhizosphere soil to fulvic acid level. [ Conclusion ] The application of a proper amount of fulvic acid （100 kg/hm2 ） could significantly promote the growth of root system of apple rootstock, increphosphatase in rhizosphere soil,so as to improve the absorption and utilization of phosphorus in apple seedlings.