Research on variation pattern of brix in sweet sorghum stalk for energy use.

Select Liaotian 1 and Liaotian 3 as test materials,their brix of stalk juice at the grain filling stage,milk stage and maturing stage were determined.The variation pattern of brix in different internodes and relationship between whole stalk brix and brix in different internodes at maturity stage were analysised.The results showed that sugar content in stalk of sweet sorghum improving with the development of the growth process.The maximum brix appeared at dough stage or beginning of maturing stage,at the same time,the number of internodes with high sugar content reach a high proportion.Brix revealed the low-high-low trend during the three growing stages.The distribution of sugar in different internodes presents a shape likes parabola.Sugar content in the upper part of stalk were high and changed actively.The highest brix of Liaotian 1 and Liaotian 3 were both at 6th internode.The standard deviation between whole stalk brix and brix in different internodes trended to W-shape curve.The whole stalk brix of Liaotian 1 and Liaotian 3 can be used to represented by the average brix of internode No.(3+9)/2 and internode No.(4+10)/2 respectively.