施磷对玉米吸磷量、产量和土壤磷含量的影响及其相关性

Effect of phosphorus application on soil available phosphorus and maize phosphorus uptake and yield

为了给玉米磷高效利用提供理论依据,在低磷土壤（Olsen-P 4.9 mg.kg^-1）上,通过田间试验,研究了施磷0（T0）、50 kg（P2O5）.hm^-2（T1）、100 kg（P2O5）.hm^-2（T2）、200 kg（P2O5）.hm^-2（T3）、1 000 kg（P2O5）.hm^-2（T4）对两个玉米品种＂鲁单9002＂（LD9002）、＂先玉335＂（XY335）的产量、磷素吸收利用及根际磷动态变化的影响。结果表明：两玉米品种根际土。

To simultaneously enhance maize yield and phosphorus fertilizer efficiency,the effects of phosphorus application on maize phosphorus uptake and utilization,yield,and the dynamic changes of rhizosphere phosphorus were studied in a field experiment.The study was conducted in low soil phosphorus（Olsen-P 4.9 mg.kg^-1） condition at Henan Province with two maize varieties — ＂Ludan 9002＂（LD9002） and ＂Xianyu 335＂（XY335）.The application rates of the P fertilizers were 0（T0）,50 kg（P2O5）.hm^-2（T1）,100 kg（P2O5）.hm^-2（T2）,200 kg（P2O5）.hm^-2（T3） and 1 000 kg（P2O5）.hm^-2（T4）,respectively.The results showed that the order of available phosphorus contents in rhizosphere and non-rhizosphere soils of the two maize varieties at different growth stages was T1 T2 T3 T4.The highest phosphorus transformation rate from non-rhizosphere to rhizosphere soils was at 61 d after maize planting under 200 kg（P2O5）.hm^-2（T3）.Also treatment T3had the highest biomass,grain yield and phosphorus transformation rate.Under 1 000 kg（P2O5）.hm^-2 phosphorus fertilizer application（T4）,no significant increase was noted in biomass and grain yield compared to intermediate phosphorus level.However,maize phosphorus uptake was much higher under treatment T4.Phosphorus transformation rate of XY335 after flowering was lower than that of LD9002,suggesting higher phosphorus use efficiency by LD9002.Correlation analysis showed significant relationships among available phosphorus contents of rhizosphere and non-rhizosphere soils and phosphorus accumulation in stems and leaves of LD9002,especially at 79 d after planting.Also significant relationships were noted among available phosphorus content of rhizosphere and non-rhizosphere soils and those of stems and leaves of XY335,especially at 47 d after planting.This suggested that 79 d and 47 d after planting were key phosphorus demand periods after planting in LD9002 and XY335,respectively.Available phosphorus content of rhizosphere and non-rhizosphere soils reflected the capacity of the soils to release phosphorus.Suitable phosphorus concentration of rhizosphere and non-rhizosphere soils for the highest phosphorus uptake were respectively 54.95 mg.kg^-1 and 32.99 mg.kg^-1 at 79 d after planting LD9002.The corresponding values for XY335 were respectively 51.24 mg.kg^-1 and 35.35 mg.kg^-1at 47 d after planting.When phosphorus application rate increased to 1 000 kg（P2O5）.hm^-2,no significant difference existed in terms of yield,biomass and phosphorus uptake compared with those under phosphorus application rate of 100~200 kg（P2O5）.hm^-2.