Studies On Use Of Biochemical Characters And Molecular Marker In Sugarcane Breeding

1. Sugarcane biochemical breeding Twelve sugarcane varieties were planted in the field to research the changes of biochemical characters in +1 leaf of different varieties at different growth stages, and to explain the relationship between biochemical characters and economic characters by sta? tistical theory. The main results are as follows: (1) Changes and differences of biochemical characters in +1 leaf of different varieties at different stages. 1) The changes of chlorophyll content in different varieties were various at different growth stages, so varieties were divided into two types., For type one, such as C033l, Xuanzhe 3, ROC1 and ROC1O, the chlorophyll contents were highest at seedling stage, then decreased, and showed lowest at technical maturing stage: For type two , such as Yuetang 57/423, Yunzhe 71/388, Mingtang 70/611 and F134, the chlorophyll contents increased from seedling stage to tillering stage, then decreased, and showed lowest at technical maturing stage. 2) The NADP梞alic enzyme activity in different varieties showed the same trend of changes at different growth stages. It exhibited the low enzyme activity at seedling stage, had an activity peak at tillering stage, decreased since elongating stage, and showed the lowest at technical maturing stage. However, the intermedium條ate varieties such as Yuetang 71/210, Yuetang 63/237, C0331 and Xuanzhe 3 were still possessed relatively high enzyme activity at the stage. 3) The ATPase activity in different varieties was highest at seedling stage, and then lowered sharply, and lowest at elongating stage, but somewhat restored at technical maturing stage. 126 - I I? ?.j.J. .L .L. - 4) The acid invertase activity in different varieties was relatively high at seedling, tillering, and elongating stages, but low at technical maturing stage. However, The change of neutral invertase activity is quite opposite to acid invertase activity. The varieties with high sucrose梒ontent often possessed low acid in? vertase activity and high neutral invertase activity, but the varieties with low sucrose梒ontent had high acid invertase activity and low neutral invertase activity. 5) The ainylase activity in different varieties showed fluctuated changes at different growth stages. The early and middle maturing varieties showed markedly higher anylase activity at seedling, tiilering, and elongating stages, but low at technical maturing stage. The late maturing varieties appeared high aznylase activity in technical stage. 6) The sucose?梡hosphatase activity in the varieties didn?t exhibit significant differences at seedling, tillering, and elongating stages, but significant differences at technical maturing stage. The sucrose?梡hosphatase activity in the varieties was fluctuated at different growth stages. The results of variance analysis showed that the differences of chlorophyll contents, NAPD梞alic enzyme activity, acid invertase activity, neutral invertase activity and amylase activi...