旱地小麦深施磷肥对土壤水分及植株氮素吸收、利用的影响

Effect of Deep Application of Phosphorus Fertilizer on Soil Moisture,Plant Nitrogen Absorption and Utilization in Dryland Wheat

为探明磷肥在旱地小麦生产上的作用,寻求旱地小麦最佳施磷方式,在山西省闻喜县进行了低磷(75kg·hm^(-2))、中磷(112.5 kg·hm^(-2))、高磷(150 kg·hm^(-2))3个施磷量条件下20 cm、40 cm 2个深度施磷的田间试验,研究其对旱地麦田土壤水分及植株氮素吸收、利用的影响。结果表明:增加施磷量,越冬期-孕穗期0~100 cm土层土壤蓄水量提高,且深层施磷效果较好,尤其有利于返青期土壤蓄水量提高。增加施磷量,各生育时期植株含氮率提高,各生育时期植株氮素积累量显著提高,且深层施磷效果较好,尤其开花期含氮率。增加施磷量,花前各器官氮素运转量显著提高,深层施磷叶片氮素运转量对籽粒的贡献率提高,成熟期叶片氮素积累量及其所占比例显著降低。40 cm深度施磷150 kg·hm^(-2)花后氮素积累量最高。此外,越冬-孕穗期0~100 cm土层土壤蓄水量与花前氮素运转量关系密切,尤其与叶片氮素运转量关系密切,开花期土壤水分与花后氮素积累量关系系数最大。总之,增加施磷量,有利于提高花前1 m内土壤水分,有利于促进植株氮素积累、运转,且深层施磷效果显著,尤其可促进叶片氮素转移到籽粒,有利于开花期含氮率提高,有利于花后氮素积累。最终,40 cm深度施磷150 kg·hm^(-2)可显著提高旱地小麦氮肥吸收效率、氮肥生产效率、氮素收获指数。

In order to investigate the role of phosphorus （P）in dryland wheat production,trying to find out the best ap-plication way of phosphorus fertilizer of dryland wheat,a field test was carried out in Wenxi,Shanxi province.It includ-ed three phosphorus application levels of low（75 kg·hm^-2 ）,middle（1 12.5 kg·hm^-2 ）and high（150 kg·hm^-2 ）,and the application depth was divided into 2 levels （20 cm、40 cm）to study the effect of phosphorus fertilizer on nitrogen （N） absorption and utilization of dryland wheat and soil water.The results showed that increasing the amount of P from Win-tering Period to Booting stage,0 -100 cm soil water storage can be increased and the deep P application had a better soil moisture.Deep P application can also increase soil water storage in turning green stage.Increasing the amount of P, N content of plant at different growth stages was increased and the N accumulation amount at different growth stages was significantly improved.Furthermore the deep P application had a higher N content and acumulation especially in the an-thesis stage.Increasing the amount of phosphorus,the translation of N before anthesis was significantly increased.Deep P application promoted leaf nitrogen to be translated into grain.N accumulation amount and N rate of leaf at maturity was significantly decreased.The accumulation of N was the highest at 40 cm depth when applying 150 kg·hm^-2 P.In addi-tion,the relationship between 0-100 cm soil water storage from Wintering stage to Booting stage and translation amount of nitrogen before anthesis had a close relationship.0 -100cm soil water particularly related to the translation amount of leaf nitrogen.The relationship between soil moisture and N accumulation in the flowering stage was the tightest.In short,increasing the amount of P was beneficial for improving the soil moisture at I m depth,It was helpful to promote plant N accumulation,translation.In addition the deep P application helped the translation of N from leaves to grain.It was also helpful to promote the N rate in anthesis stage.Last but not lest,it promoted the nitrogen accumulated after an-thesis.To sum up,40 cm depth applying 150 kg·hm-2 P fertilizer significantly increased N uptake efficiency,N productive efficiency and N harvest index.