Studies Of Seawater-Tolerant Physiological Diversities Mechanisms Of Different Genotype Helianthus Tuberosus L. And The Cultivated Technology In Mudflats Along Coast

It is significative to exploit regeneration resource and energy, such as biologic-energy and biologic-chemistry matter, to decrease the requirement of petroleum for economy development. Helianthus tuberosus adapts many kinds of environment, especially can be planted in badlands and mudflats along the coast.Genotype varieties of H. tuberosus were used to select systemicly high yield and quality one to plant in mudflats along the coast in field and greenhouse experiments in the study. The characteristics on physiology and biological-chemistry of H. tuberosus under seawater stress were investigated. The mechanisms of tolerance-seawater and metabolize of representative H. tuberosus were studied. The disciplinarian of fertilizer needed for H. tuberosus and zoology security for mudflats irrigated with seawater were also researched. The results were below:1) Compared with the control, the growth speed of fresh and dry weight of shoots and roots of eight H. tuberosus genotype seedlings treated with 15% and 30% seawater all decreased. The MDA content and electrolyte leakage in leaves and contents of Na⁺ and Cl^- in the shoots and roots increased with seawater concentration increasing. The Nanyu No.1 and Nanyu No.8 were more seawater tolerant than other genotype. There was significantly negative correlation between the fresh and dry weight of shoots and roots and the contents of Na⁺ in the roots. And there was significantly negative correlation between the fresh weight of shoots and roots and the contents of Cl^- in shoots and roots. There was significantly positive correlation between the dry weight of shoots and roots and the contents of K⁺ in shoots and roots. Based on those, the H. tuberosus of eight genotypes tested could be divided into three groups, such as high seawater-tolerance, intermedia seawater-tolerance and low seawater-tolerance. The the katabatic scopes of fresh weight and dry weight and contents of Na⁺, K⁺ and Cl^- in the shoots and roots could be used as physiological indices for selecting different tolerant-seawater genotype H. tuberosus. There was intensity difference of isoperoxidase bands by the in polyacrylamide gel electrophoresis to check the descendiblity relation of genotypes.2) Field experiments were carried out to study effects of seawater irrigation on yield compositions and ion distribution of different genotypes of H. tuberosus growing in coastal mudflat along semiarid regions in 2005. Nanyu No.2 was higher than the others in biomass of the roots and aerial parts, and. Nanyu No.5 and Nanyu No.3 were taller than the others in all treatments, but the effect on diameter of the main stems of the plants varied sharply with treatment. In the treatment of irrigation with 30% seawater, Nanyu No.1 was not affected in biomass accumulation in roots and aerial parts, but the others to a varying extent. The plants differed sharply in yield between genotypes. Nanyu No.2 was the highest when irrigated with 30% seawater, and so did they in single tuber weight, total sugar and inulin content. Nanyu No.1 and Nanyu No.2 were the highest in unit tuber weight. Concentrations of Cl^- and Na⁺ in roots, stems and leaves of all genotypes increased with the seawater concentration increasing, but significant differences did exist between genotypes. Na⁺ content was lower in leaves than in roots and stems. Judging by biomass accumulation, yield of tubers, total sugar and inulin contents in tuber, and ion distribution, Nanyu No.1 and Nanyu No.2 were more adaptive to planting in coastal mudflat along semiarid regions with seawater irrigation than other genotypes.3) The changes of activities of SOD, POD and CAT and contents of MDA of three H. Tuberosus genotypes seedlings leaves of seawater-tolerance Nanyu No.l, intermedia seawater-tolerance Nanyu No.6 and low seawater-tolerance Nanyu No.7 were different under seawater treatments. Nanyu No.1 was injured less under seawater treatments than Nanyu No.7 and Nanyu No.6 judged by lipid peroxidation degree in leaves. The contents of proline and soluble sugar of H. Tuberosus genotypes seedlings leaves were different under seawater treatments. And the contents of proline and soluble sugar both changed with time lasting. There were different effects on the physiological and metabolize characteristics of H. Tuberosus genotypes seedlings under seawater treatments. Nanyu No.l was more seawater-tolerant than Nanyu No.7 and Nanyu No.6.4) The distributions of ions in the cells of roots, stems and leaves of seawater-tolerance Nanyu No.1 and low seawater-tolerance Nanyu No.7 were analyzed by X-ray microanalysis technique. The contents of Na⁺ and Cl^- in the cells of roots, stems and leaves increased with seawater concentration increasing. But there was difference between the Nanyu No.1 and Nanyu No.7. The Na⁺ peak value of Nanyu No.1 was higher than Nanyu No.7. And the Na⁺ percent in the ions of Nanyu No.1 was also higher than Nanyu No.7. The Na⁺ and Cl^- percents in the ions of the two genotypes were over 50%, even over 80% in the stelar parenchyma cell under 30% seawater treatment. The peak values of K⁺, Ca²⁺ and Mg²⁺ did not change significantly under different treatments. But K⁺, Ca²⁺ and Mg²⁺ percents in the ions under 15% and 30% seawater treatments all were lower than under 0% seawater treatment.5) Chloroplast ultrastructures of Nanyu No.l and Nanyu No.7 under 0%, 15% and 30% seawater treatments were observed by clairvoyant micrograph. The configuration of chloroplast was blurry and disaggregation under seawater treatment. And the membrane was dilapidated. The configuration was also wrecked. But the breakage of Nanyu No.l chloroplast was lower than Nanyu No.7.6)The concentrations of chlorogenicacid and low molecular weight compounds were determined by high performance liquid chromatography with a coulometric array detector (HPLC-CAD) . The concentrations of chlorogenicacid did not change significantly under 0% seawater treatment along the time lasting. While it changed significantly under 15% and 30% seawater treatment along the time lasting. It was higher after treatment for 1 hour than for 2 and 3 hours under 15% seawater treatment. While it was higher after treatment for 3 hour than for 1,2 and 6 hours under 30% seawater treatment. Some other compounds was observed as well during the treatment. They are believed to below molecular weight compounds and subject to further investigations.7)The field experiment was also carried out in seashore in Laizhou, Shandong Province to study the effect of salt and fertilizer application coupling under irrigation of different concentration seawater on H. tuberosus by orthogonal design. It was that W₂N₃ and W₂P₃ were the optimized combinations through the analysis of alternant effects of seawater, nitrogen and phosphorus. The main element that affected the yields was seawater, then fertilizers of N and P were subordinate. And the best combination was W₂N₃P₃.8) The fresh weights of roots and aerial parts increased with the concentration of phosphorus supplementation. The trends of dry weights of roots and aerial parts resembled the trends of fresh weights with the same treatments. The contents of proline and soluble-sugar increased with phosphorus supplementation. The activities of SOD, POD and CAT all significantly stimulated with phosphorus supplementation. The MDA content and ELP decreased with phosphorus supplementation. And the contents of Na⁺ and Cl^- decreased with phosphorus supplementation. Compared with the control, the contents of K⁺, Ca²⁺and Mg²⁺of the aerial part and root increased with phosphorus supplementation. Phosphorus enrichment of the seawater ameliorated the toxicity of seawater in H. tuberosus seedlings. Nitrogen supplementation of the seawater resulted in increasing fresh and dry weight of shoot and roots when compared with seawater treatment without N supplementation. Nitrogen supplementation of the seawater significantly enhanced the activities of antioxidant enzymes in leaves compared to the seawater treatments alone. Addition of N to seawater enhanced the contents of proline and soluble-sugars in the leaves, K⁺ and total-N of aerial parts and roots. N supplementation resulted in a declined concentrations of Na⁺ and Cl^- in aerial parts and roots of seawater-stressed plants. Nitrogen enrichment of the seawater ameliorated the toxicity of seawater in H. tuberosus by improving the antioxidative enzymes, accumulating of proline and soluble-sugars and altering the distribution of inorganic ions.9) Distribution and migration of Na⁺, Cl^-, Ca²⁺, Mg²⁺, K⁺ in 0-40cm soil irrigated by seawater were investigated. There was 515 mm rainfall in the whole postemergence. Though content of salinity in 0-5cm layer changed drastically, it reached the controlled level (no irrigation) when if. tuberosus were harvested. Salinity was accumulated conspicuous in 0-40cm soil layer and would brought on secondary salinization when the seawater irrigation concentration was 75%. Some agricultural measures must be afforded to stand off secondary salinization if no enough rainfall. There was a significant change of salinity in plough layer soil when irrigated by 25% seawater. Na⁺ and Cl^- were primarily distributed in 5-20cm layer, and Ca²⁺ and Mg²⁺ in 20-40cm with seawater irrigation.