湖南山核桃叶片矿质营养年周期的变化规律

为给湖南山核桃栽培管理提供科学依据,对湖南山核桃叶片N、P、K、Ca、Mg、Fe、Mn、Cu、Zn等矿质元素年周期内含量变化规律进行了研究.结果表明:生长初期,N、P、K、Cu的含量迅速下降,7月以后P、K开始回升,P在8月果仁生长期有所下降,9月采果后有小幅度上升后逐渐下降,K在7、8、9月连续上升后下降,而Cu则在采果后一段时间才有所升高；Ca、Mn先下降后迅速上升,7月份趋于平稳,落叶前迅速上升,并达到全年最高；Mg、Fe、Zn初期呈逐渐上升趋势,中期总体变化幅度较小,后期含量呈下降趋势.研究初步认为:P、K、Ca营养诊断取样可在7月进行,Mg、Zn可提前到6月进行,N、Fe、Mn可推后到8-9月进行,Cu在10月以前进行.

Annual Periodic Change of Mineral Nutrition in Leaves of Hunan Hickory

The annual periodic change regulation of N,P,K,Ca,Mg,Fe,Mn,Cu and Zn content in leaves of Hunan hickory was studied to provide the scientific basis for its cultivation and management.The results showed that N,P,K and Cu content in leaves reduced rapidly at early growth stage,and P and K content in leaves began to rise after July.P content in leaves declined at kernel growth stage in August,and first increased and then declined gradually after harvesting in September.K content in leaves continuously increased in July,August and September and then decreased.Cu content in leaves increased after harvesting.Ca and Mn content in leaves presented a first decline and then rapid rise trend and reached the highest before defoliation.Mg,Fe and Zn content in leaves presented a gradual rise trend at early growth stage,a relative stable trend at middle growth stage and a decline trend at later growth stage.In conclusion: The suitable diagnosis time of P,K and Ca,Mg and Zn,N,Fe and Mn,and Cu should be in July,in June,in August and September and before October respectively.