Nutrient diagnosis of ‘Fuji’ Apple in west Liaoning Provinceusing compositional nutrient diagnosis (CND) method

【Objectives】 The cultivation areas and yields of Fuji apples in west Liaoning Province account for a larger proportion of the total apple production in Liaoning Province. The fertilizer managements are deficient in scientific base. The Compositional Nutrient Diagnosis method (CND) is preliminary used for the study of the status of ‘Fuji’ apple nutrition in west Liaoning Province, and provides a guide for the orchards fertilization management. 【Methods】 Eighty six representative apple orchards were selected, the yields, fruit qualities and contents of nitrogen (N)、 phosphorus (P)、 potassium (K)、 calcium (Ca)、 magnesium (Mg)、 iron (Fe)、 copper(Cu)、 manganese (Mn)、 zinc (Zn) were measured. The CND method was adopted for dividing the samples into high and low production level subpopulation, and bringing the low production level subpopulation nutrient diagnosis into force. The yield cutoff value of high production level subpopulation was confirmed by CND, and the procedures of fruit quality evaluation composite scores cutoff value were as follows: firstly, the six indexes of fruit quality were normalized; secondly, the principal component analysis was carried out on the six indexes, composite evaluation scores of six indexes were determined; thirdly, by the method of CND, fruit quality composite evaluation scores cutoff value was obtained. Orchards which met with the CND and expert consultation method standards of yield and quality cutoff values at the same time were separated from the samples. CND norms were calculated according to the high level production subpopulation nutritional status. Based on which, leaf nutrient diagnosis was put into effect, and the condition of nutrient was present. 【Results】 The leaf analysis with CND indicated that yield cutoff value of the high production level subpopulation was 44.556 t/ha, the fruit quality evaluation composite scores cutoff value was 0.792. There were 13 orchards which met the conditions, accounting for 15.12% of the total orchards. The CND norms were VN*=2.776, VP*=0.212, VK*=1.884, VCa*=2.042, VMg*=0.814, VFe*=-2.470, VCu*=-5.090, VMn*=-2.631, VZn*=-3.867, VR*=6.330; SDN*=0.173, SDP*=0.144, SDK*=0.155, SDCa*=0.266, SDMg*=0.307, SDFe*=0.189, SDCu*=0.474, SDMn*=0.467, SDZn*=0.325, SDR*=0.134; the low level production subpopulation fertilizer orders were Fe Mn P N Ca K Cu Zn Mg. 【Conclusions】 The leaf analysis is established on the yield and fruit quality with CND. The investigation results obtained using the method show that in west Liaoning Province, the criteria for high yield is 38.451 t/ha, for good fruit quality is 0.792. The number of orchards meet the two criteria is 13, only accounting for the 15.12% of the total orchards. In ‘Fuji’ apple of west Liaoning Province, Fe, Mn, P and N are in deficiency; soil available Fe and Mn contents are appropriate, soil N and P are deficient. Therefore, N and P fertilizers are recommended to be applied in small amount and several times, Fe and Mn could be foliar sprayed appropriately in the apple production of west Liaoning Province.