| This flue-cured tobacco variety of K326 was used in this experiment to research the effect of different SPAD threshold on
dry matter, nitrogen accumulation, yield and quality of flue-cured tobacco in the mode of RTNM. The results showed that in the mode of RTNM management, with the SPAD threshold increased in the range from 38~43, the dry matter, nitrogen accumulation, yield and quality of flue-cured tobacco was added also in every flue-cured tobacco organs. However, when the SPAD threshold was in excess of 43, the yield and quality were no longer added or added extent reduced. Even when it was in excess of 48, the dry matter, nitrogen accumulation,yield and quality were reduced contrarily. In general, in this experimental conditions, the SPAD threshold was in the range from 40.5~43 in the mode of RTNM when the nitrogen rate was in the range from 75 to 110 kg/hm2, the variety of K326 could get higher dry matter,nitrogen accumulation, yield and quality, which was worth of recommendation and application in the procession of plant. |
