Abstract: Abstract: It has illustrated that application of controlled-release fertilizers obviously saved labor power and fertilizers, and significantly increased yield as well for rice production. Pot trials and cylinder trials were carried out in 2002-2005 to study the mechanism of single basal application of controlled-release fertilizers for increasing yield of rice (Oryza Sative L.). The trials involved in the following 6 treatments, splitting Nongke rice-specific fertilizer (SNRSF, ck), single basal of Nongke rice-specific fertilizer (BNRSF), single basal of Nongke controlled-release fertilizer (BNCRF), single basal of controlled-release fertilizer with NH4MgPO4 coated (BLCRF), single basal of bulk blend fertilizer with resin coated urea (BCUF), no fertilization (NF). It was observed, that treatments of BLCRF and BNCRF resulted in apparently higher concentrations of soil available N than BCUF, while soil available N of SNRSF fluctuated greatly within 30 days after fertilization. After 30 days of fertilization, there were no significantly differences in soil available N concentrations among the fertilization treatments under rice planting, however, available N concentrations for the 3 treatments of controlled-release fertilizers (CRFs) were greater than SNRSF without rice planting. In comparison to SNRSF, better nutrition from the CRFs resulted in the following advanced characteristics. (1) CRFs developed larger rice root weights, volumes, total absorption areas and deeper distribution, higher root bleeding intensity, with greater output intensity of amino acids in root bleeding through out all the growth stages. (2) There were higher chlorophyll concent and activity of CAT, but lower POD for the CRFs in the flag leaves after 12 days of flowering, in which dissoluble protein decomposed slower during all filling stages. (3) Application of the CRFs enlarged the base of rice stems, declined the proportion of shoot and root, increased root depth index. These indicated that single basal application of the CRFs should be able significantly to promote development of root system, enhance nutrient uptake, slower senescence speed and strengthen the capacity of lodging resistance.

Key words: Rice, Single basal fertilization, Controlled-release fertilizer, Root system, Senescence, Lodging resistance