Rice Biomass - Leaves "a Preliminary Study Of The Diagnosis Of Top-dressing Method

This study took Changyou 1 and wujin 15 as test materials,by earlier nitrogenous fertilizer of 0,4.5,9,13.5,18,22.5kg/mu,set up six level group quality about larger,largr,ordinarily,small.By that foundation,middle-latter nitrogenous fertilizer of 0,4.5,9,13.5,18,22.5kg/mu was used to set up 22 different group quality for studying the correlationship between dry matter,leaf colour and nitrogen absorbed , explore how to use the nitrogenous fertilizer by Dry matter—leaf colour diagnosis.This study can improve the nitrogenous fertilizer precision, nitrogenous fertilizer precision is value for theory and practiseThe major results are showed as followings:1. The treatment of different earlier fertilizer and nitrogen dressing for spike had notability effect to yield,Both of the materials had higher yeild when nitrogen applied at middle-later stage by 13.5kgN/mu and nitrogen applied at the earlier by 0 and 13.5kg/mu; Both of the materials had higher yeild when nitrogen applied at middle-later stage by 9 kgN/mu and nitrogen applied at the earlier by 9 and 13.5kgN/mu.There was a two curve correlationship between middle-later nitrogen applied(X) and yeild (y).2. The treatment of different earlier fertilizer and nitrogen dressing for spike had notability effect to group quality dry matter. The group quality dry matter of heading stage to maturity stage was regulated and controled by the nitrogen dressing for spike . There was a two curve correlationship between middle-later nitrogen applied and maturity stage dry matter,dry matter of heading stage to maturity stage.The two curve corcorrelation of middle-later nitrogen applied (X) and yeild (y) displayed that higher earlier fertilizer and nitrogen dressing for spike had disadvantage to the accumulation of middle-later dry matter.3. The treatment of different earlier fertilizer and nitrogen dressing for spike had notability effect toleaf colour. There existed significant linear correlation between Different Leaf SPAD value and leaf Nitrogen content,plant Nitrogen content.The SPAD value of third leaf from the top was most correlated with the whole leaf N concentration,the correlation value was 0.9167** and 0.9047**. Third leaf from the top was the most ideal indicator leaf when using SPAD value or leaf color difference to diagnose N status and make N fertilization suggestion for spike in rice. Earlier fertilizer and nitrogen dressing for spike improved plant Nitrogen content and leaf color,but the effection time correlated to nitrogen dressing for spike and group quality.4. The treatment of different earlier fertilizer and nitrogen dressing for spike had notability effect to nitrogen absorbed. Earlier fertilizer improved jointing stage group quality nitrogen absorbed, nitrogen dressing for spike had driver function to group quality nitrogen absorbed at maturity stage, middle-later nitrogen applied (X) and maturity stage nitrogen absorbed displayed conic.5. According to the correlation between group quality dry matter, SPAD value of third leaf from the top, nitrogen absorbed and yeild ,we acquired the trends indices for high yeild group quality dry matter,leaf color and nitrogen absorbed.Identified the precise correlation of nitrogen dressing for spike,leaf color and nitrogen absorbed.6."group quality dry matter×leaf color"indicated group quality nitrogen absorbed, established trends indices for high yeild group quality about ."group quality dry matter×leaf color", identified that the value of ."group quality dry matter×third leaf (SPAD)/100"was a important index for diagnose.We also established the forecast formulae for middle-later nitrogen base on nitrogen dressing for spike(x1),"group quality dry matter×third leaf (SPAD)/100"(x2)and high yeild group quality"group quality dry matter×leaf color/100".