Biochemical Mechanism Of Aphis Sacchari.Zehntner Resistance In Sorghum Variety 'Henong16'

Sorghum is the important cereal crop, and occupies the fifth place which is only inferior to the place of wheat, rice, maize and barley. It has the characteristics such as high yield, drought and waterlogging tolerance, saline and alkaline bearing etc, so it is an important crop in the world. Besides food, sorghum is mainly used to making fodder, wine and paper. In addition it can become a new source of energy because of its high biomass. Melanaphis sacchari Zehntner is one of the influential pests on the Sorghum, which leads to the heavy loss to the global output and quality every year. Using the resist varieties is the most economical, safe and effective measure to avoid invading from aphids. However, there are too little germplasm of resisting aphid in our country, and the varieties resisting aphid with high-quality are much less. Therefore, cultivating the resistant aphid varieties with high-quality becomes the urgent demand for sorghum breeding. The study about mechanisms for anti-aphids becomes more and more important.Henongl6, resisting aphid material with high-quality, was used for the contrast in this study. And several other materials which have the different hereditary backgrounds were used. Based on these materials, the biochemical mechanism of resisting aphids was analyzed from different aspects. The analysis on solution sugar, free amino acid, starch, tanning, POD, PPO, and PAL is carried out in the study. The aim is to screen the main biochemical materials which are correlative to the character of resisting aphid.1. The trait of anti-aphid in sorghum was corrective with the content of soluble sugar. The soluble sugar content in the anti-aphid cultivar was higher than in the susceptible cultivars before invading by Melanaphis sacchari Zehntner. When the aphid invaded the sorghum, Henongl6 was immune and its soluble sugar content was obviously lower than the susceptive ones invaded by aphid. Base on this regular the soluble sugar content could be the criterion to identify if the cultivar is susceptible to the aphid.2. PAL activities expressed in high level in Henongl6 before the aphid happened. In addition they had significant difference to the other susceptible cultivars. Furthermore, after invaded the changes of PAL activities showed the. regulation that the degree of theirs...