Currently, maize production in China suffers from many problems, such as excessive fertilizer application, inefficient use, and insufficient agricultural labour. The effect of one-time mechanical point-applied fertilization controlled-release compound the root-zone on yield nutrient uptake was investigated to explore efficient patterns for decrease increase maize. selected a granular (24-6-10 N...

Controlled release fertilizers (CRF) are produced with different rates and durations of nutrient release to cater to different crops with wide ranges of nutrient requirements. A rapid technique is needed to verify the label specifications of nutrient release rate and duration. Polymer-coated urea (PCU) (43% nitrogen [N]) and polymer-coated N, phosphorus (P), potassium (K) (PC_NPK; 14-14-14) fer...

Application of polymer-coated controlled-release fertilizers (CRF) during outplanting has resulted in variable growth responses in the Pacific Northwest (PNW). Results have been linked to several factors, including soil moisture availability. Multiple experiments were designed to examine the influence of CRF on Douglas-fir seedling root architectural development and establishment. Placement of ...

We established Populus deltoides Bartr. stands differing in nitrogen (N) availability and tested if: (1) N-induced carbon (C) allocation could be explained by developmental allocation controls; and (2) N uptake per unit root mass, i.e., specific N-uptake rate, increased with N availability. Closely spaced (1 x 1 m) stands were treated with 50, 100 and 200 kg N ha(-1) year(-1) of time-release ba...

Fertilizer application control in reason is the key technology to improve operation quality, reduce fertilizer pollution, and cut down costs of production. A control system of variable rate fertilizer is developed based on microcontroller chip in the paper. The system can automatically control flow dosage by adjusting feed gate opening size and changing hydraulic motor speed of fertilizer conve...

Abstract. Large quantities of N fertilizers may be lost in rice fields by nitrification-denitrification. In this connection, experiments were carried out in order to compare the effects from slow-release N-fertilizers (ISODUR) and products integrated with diciandiamide (DCD), a nitrification inhibitor, with the N splitting method applied in two or three times on the rice growth and yield. The e...

This note demonstrates that a certain class of stochastic problems for determination of optimal fertilizer application rates in the presence of fertilizer carry-over can be simplified to static, certainly equivalent problems. Conditions required for certainty equivalence to hold are: (1) fertilizer carry-over is agronomically equivalent to applied fertilizer; and (2) some addition of fertilizer...

resulted in highest leaf N content. Only one-half the amount of controlled release N was used on plants in the combination treatment as was used on plants where controlled release N was the only fertilization. Soil tests did not show significant variation between treatments with regard to pH, salinity, P, K, Ca and Mg content. The pH ranged from 6.5 to 7.4 and the salinity was not high enough t...

Abstract In this study, an eco-friendly controlled release fertilizer cellulose-based hydrogel was prepared from cellulose fibers derived wastepaper, epichlorohydrin (ECH) as a crosslinker and carboxy methyl (CMC) gelling agent. A maximum swelling capacity of 2000% achieved for with optimum composition. The soil moisture contents in the presence optimized hydrogels were determined using digital...