Changes in nutrition components in hazelnut during fruit development

Three hybrid hazelnut(Corylus heterophylla) lines,82-11,84-237 and 84-402,were selected to study changes in nutrition components as well as their correlations with N,P and K.The results showed that the content of reducing sugars decreased in the initial stage and recovered slightly during the late stage.The content of sucrose showed an increasing trend and was the main soluble sugar in maturing kernel.Total soluble sugar content decreased in kernel growth phase and increased gradually from kernel filling phase till full maturity.Starch content increased first and then decreased to and maintained at a low value for a period and increased finally.Crude fat and crude protein contents increased constantly.The accumulation of sucrose and soluble sugars occurred mainly during the late stage of kernel development,while crude fat and crude protein accumulation occurred mainly during the initial and middle stage of kernel development.There existed significant positive correlations between crude fat and N,P and K.