Physiological Mechanism And Proteomics Of Solanum Tuberosum L.Ninglang182Response To Drought Stress

Solanum tuberosum L. is an important food crop for the world and China. The potaoto is very sensitive to water shortage. In China, more than half of the potato crops are planted in arid and semi-arid areas. The impact of water shortage on the yield and quality of S. tuberosum has severely limited the development of china’s S. tuberosum industry. Cultivating the drought resistant variety is important to reduce the loss caused by drought. Currently, the study of S. tuberosum drought resistance mainly focuses on morphology, physiology and transgenic breeding. However, the molecular mechanism of drought resistance in S. tuberosum leaves has not been reported. In this project, different drought stresses (drought, semi-drought, normal) were applied to Ninglang182(drought-resistant variety) and Zuoli Yangyu (normal variety).The stresses response about growth and physiological characteristics form above varieties were compared. Ninglang182, a stronger drought-resistant local variety of S. tuberosum in Yunnan province, was used to explore molecular mechanism using2D and MS. These research will provide more evidence to help breed modification for drought-resistant varieties of S. tuberosum. The main research results were followed as below:1. The morphology of the Ninglang182and the Zuoli Yangyu were influenced apparently after drought treatment. Each growth index (germination rate, plant height, root fresh weight, root drought weight, root water content, stem fresh weight, stem drought weight, stem water content, leaf fresh weight, leaf drought weigh, leaf water content, coverage, anti-pulling capacity) were declined after drought stress. The decline degree of Zuoli Yangyu was higher than Ninglang182. The content of malondialdehyde(MDA) in Ninglang182and the Zuoli Yangyu were elevated after drought treatment. The elevation degree of Ninglang182was lower than Zuoli Yangyu. the enzyme activity of superoxide dismutase(SOD), peroxidase(POD) and catalasethe(CAT) in Ninglang182were elevated after drought treatment, the enzyme activity of superoxide dismutase(SOD) in the Zuoli Yangyu were elevated while the enzyme activity of SOD and CAT were decreased after drought treatment. So, the drought-resistant ability of Ninglang182was stronger than Zuoli Yangyu based above results. 2. The two-dimensional electrophoresis (2-DE) method of leaves in S. tuberosum was established in this research. The different protein extraction and dissolution, samples loading quantity and pI range of IPG strip in2-DE of S. tuberosum ninglang182were compared.The high-resolution2-DE maps was obtained through improved TCA/acetone method with600μg protein loading, pI4-7,24cm IPG strip. The optimized method can be applied to the experimental research on the S. tuberosum leaf’s total protein dielectrophoresis. To analyze the Proteomics variance of Ninglang182leaf under drought stress. There are40points which are significant differences,24protein spot expression indexes raised greatly, and16protein spots expressed distinctively. After doing Mass Spectrum identification on these40different proteins, the different proteins functions were classified as follows:stress response (16proteins), metabolism (14proteins), Biomanipulation (3proteins), transportation (2proteins), development (2proteins), cellular component (2proteins), and signal transduction (1proteins). The results indicated potao can elevate drought-resistant ability through multi biological way and regulation level.