控释肥料养分在香蕉假植苗专用基质中的释放特征

Nutrient release characteristics of controlled release fertilizer in specific matrix for culturing banana nursery stock

【目的】探讨控释肥料养分在香蕉假植苗专用基质和恒温(25℃)静水培养中的释放特征,为假植苗培育过程的水肥管理提供理论依据。【方法】以静水培养为对照,采用基质包埋培养法测定控释肥料的养分累积释放率及肥效期。【结果】(1)同种控释肥料在2种介质中的养分释放特征曲线同型,但同期释放量不等。(2)基质和静水中肥效期28 d、126 d和196 d的控释肥料(CRF1、CRF2和CRF3)养分累积释放率之差异分别在5.57%~24.72%、3.20%~22.98%、0.15%~17.85%。(3)基质水分含量在50%以上时,2种介质中控释肥料的养分累积释放率呈极显著正相关。【结论】培养介质不会改变控释肥料养分释放模式,对养分释放率的影响程度随肥料肥效期的延长而减小。CRF1适于作追肥,CRF2、CRF3适于作基肥。基质水分含量在50%以上时,可用静水中控释肥料养分的释放率准确预测其在基质中的释放率。

【Objective】The difference of controlled release fertilizer(CRF) nutrient release characteristicsin specific matrix(SM) and static pure water incubation(SPW)(25 ℃)were studied in order to provide atheoretical basis for the management of irrigation and fertilization for banana nursery stock.【Method】Thenutrient release patterns and longevity of the CRF in SM were studied with SPW method as control.【Re-sult】(1) The nutrient release pattern of the CRF in SM was the same as that obtained in SPW,but the re-lease rate was different in the same period.(2)The differences of cumulative nutrient release rate betweenSM and SPW were from 5.57% to 24.72%,3.20% to 22.98% and 0.15% to17.85% for CRFs with longevityof 28 d,196 d and 280 d(CRF1,CRF2 and CRF3) respectively.(3) When the water content in SM was morethan 50%,the nutrient cumulative release rate of CRF in the SPW and SM showed a significant positivecorrelation.【Conclusion】Compared with SPW method,the nutrient release pattern of CRF was not affectedin SM,but the nutrient release rate decreased remarkably with the increase of coating thickness. CRF1 should be selected as top dressing fertilizer,while CRF2 and CRF3 should be selected as base fertilizer dur-ing the banana nursery sotck cultivation. The nutrient release rate of CRF in matrix could be accurately pre-dicted by using the correlation equation of the nutrient release rate between t SPW and SM.