Study On Annual Variation Of Mineral Element Contents In Leaves Of Different Yield Orchards Of ‘korla Fragrant Pear’

【Objective】 The purpose of this study was to investigate the changes of mineral elements in the leaves of ‘Korla fragrant pear’ during different growth periods in different production areas,and to study the changes of mineral eleme nts and the nutritional status and demand the order of ‘Korla fragrant pear’.【Method】Eighteen ‘Korla fragrant pear’ orchards from Korla area were divided into three groups based on yield:(i)low-yielding orchards,(ii)medium-yielding orchards,(iii)high-yielding orchards,the age of ‘Korla fragrant pear’ was 20~25 years.The leaf samples were collected every 15 day between April 28 and September 23.The content of N,P,K,Ca,Mg was detected during the annual growth cycle of different yield ‘Korla fragrant pear’ orchard using “Leaf Analysis” method.Through the correlation analysis,variance analysis,DRIS method to analyze the measured data for diagnosis.【Result】 From April to September,the variation of the content of each element in the leaves of ‘Korla fragrant pear’ was basically the same at the level of high,medium and low yield,the annual average of different production orchards was different.The contents of N、P、K、Ca、Mg、Fe、Cu、Zn、Mn、B、Na in ‘Korla fragrant pear’ leaves in high yield orchards were 26.96g/kg、2.84g/kg、18.40g/kg、9.19g/kg、2.24g/kg、 388.92mg/kg、9.38mg/kg、54.96mg/kg、44.15mg/kg、18.87mg/kg、683.50mg/kg,respectively;The contents of N、P、K、Ca、Mg、Fe、Cu、Zn、Mn、B、Na in ‘Korla fragrant pear’ leaves in medium yield orchards were 26.96g/kg、2.84g/kg、18.40g/kg、9.19g/kg 、 2.24g/kg 、 388.92mg/kg 、 9.38mg/kg 、 54.96mg/kg 、 44.15mg/kg 、18.87mg/kg、683.50mg/kg,respectively;The contents of N、P、K、Ca、Mg、Fe、Cu、Zn、Mn、B、Na in ‘Korla fragrant pear’ leaves in low yield orchards were 26.96g/kg、2.84g/kg、18.40g/kg、9.19g/kg、2.24g/kg、 388.92mg/kg、9.38mg/kg、54.96mg/kg、44.15mg/kg、18.87mg/kg、683.50mg/kg,respectively.The contents of Ca,Mg and Mn increased gradually,while the contents of K and Zn decreased first and then decreased.The contents of Ca,Mg and Mn increased gradually.Na content was for the slow ups and downs trend.The average annual value of each element were: the content of N、P and Cu in the medium orchard is higher than the other orchards;the content of K、Ca、Mg、Fe and Na in the high orchard is higher than the other orchards,the content of Mn and Zn in the low orchard is higher than the other orchards.2.The important parameters of foliar nutrition diagnosis of ‘Korla fragrant pear’ in Korla area were put forward in five periods: N/P、N/Fe、N/Cu、N/Zn、N/B、P/Mg、P/Fe、P/Cu、P/Zn、P/B、K/Ca、K/Mg、K/Fe、K/Cu、K/Zn、K/Mn、K/B、Ca/Mg、Ca/Fe、Ca/Cu、Ca/Zn、Ca/B、Mg/Fe、 Mg/Zn、Mg/B、Mg/Na、Fe/Cu、Fe/Zn、Fe/B、Fe/Na、Cu/Zn、Cu/B、Zn/Na、Mn/B、B/Na;There are significant differences in the important diagnostic parameters determined by DRIS standard procedures in different periods.3.The nutrient requirement and NII index of five low yield orchard were obtained by using the DRIS index calculation method of Beaufils to diagnose the nutritional status of‘Korla fragrant pear’.The order requirement of mineral elements in May:Zn>Ca>K>Cu>N>Fe=Mn=Na>P>Mg>BNII Index in May:118.23The order requirement of mineral elements in June:Na>K>Cu>Fe>P>N>Ca>Mg>Mn>Zn>BNII Index in June:170.09The order requirement of mineral elements in July:Zn>Na>Fe>K>Ca>Mn>P>Cu>N>Mg>BNII Index in July:174.75 The order requirement of mineral elements in August:Zn>Ca>P=K=Cu=Mn=B>Mg>Fe>N>NaNII Index in August: 83.54 The order requirement of mineral elements in September:P>N>Ca>K>B>Fe>Mg=Na>Mn>Cu=Zn NII Index in September: 47.78 【Conclusion】The contents of elements in the leaves of ‘Korla fragrant pear’ were different beteween April and September,the contents of N,P,Cu and B were decreased,the contents of K,Ca,Mg,Zn,Mn were increaced.The average annual content of mineral elements in pear leaves: the contents of Mg,Fe and Na in high orchard were higher than the other orchards,the contents of N,P and Cu in medium orchard were higher than the other orchards,the contents of Zn in low orchard were higher than the other orchards.The nutrition imbalance index of low-yielding orchard was the most unbalanced of all.