Annual biomass and nutrient accumulation of Korla fragrant pear Influence on Growth and Yield of Korla Fragrant Pear Under Different Treatments of N, P, K Changes of Cold Hardiness Indexes of Korla Fragrant Pears Different Organs with Air Temperature during Over wintering Period Hyperspectral estimation models for total potassium content of Kuerle fragrant pear leaves Study on characteristics of net photosynthetic rate of two kinds of tree shape and Impact Factors in Korla fragrant pear