Effects Of Ethephonephon And Paclobutrazol Applications On Ramie Yield And Fiber Quality

In recent years, the domestic production of ramie industry changed radically, except the reason of the financial crisis, environmental pressure and ramie industry mechanization degree is not high, and encountered when planting ramie fiber yield, quality and resistance. Therefore, it is urgent to find more can improve the yield and quality of ramie fiber field cultivation technology. Plant growth regulator has the advantages of small amount and high efficiency, which has been widely used in agricultural production. Plant growth retardants have many advantages, such as the promotion of the growth of the underground, the elimination of apical dominance, improve resistance and so on. However, it is rarely used and studied in the field of ramie field cultivation. In this study, we sprayed plant growth regulators(Ethephon and Paclobutrazol) in five different concentrations on “Huazhu No.5” to investigate their influences on fiber yield,fiber quality and the resistance of plant. The results may provide a theoretical basis for the application of plant growth regulators on ramie to improve the ramie yield, the fiber quality and the resistance of plant.The main results are as follows,1. Determine the production related indexes such as ramie yield, leaf yield, ramie fiber ratio from fresh stem and fresh bark, effective plant rate, the height and diameter of ramie, SPAD of ramie leaf and so on. The results showed: Ethephon and Paclobutrazol reduced the ramie yield, and the yield decreased along with the increase of the concentration. Ethephon in the concentration of 50 and 100 mg/L increased the leaf yield in the second harvest season, whereas it has no significant influence in the first and third harvest season. Paclobutrazol increased the leaf yield in three harvest seasons of the year, but the increase yield decrease along with the increase of the concentration. The application of 400 and 600 mg/L Ethephon decreased the fiber ratio from fresh stem, and decreased the fiber ratio from fresh bark in the second and third harvest season. Paclobutrazol in all of the concentrations decreased the fiber ratio from fresh stem, the ratio decreased along with the increase of the concentration. The fiber ratio from fresh bark increased at first and then decreased along with the increase of the concentrations of Paclobutrazol. The application of 200, 400 and 600 mg/L Ethephon decreased the effective plant rate significantly; Paclobutrazol in all of the concentrations decreased the rate, and it increased at first and then decreased along with the increase of the concentrations of Paclobutrazol. Ethephon and Paclobutrazol decreased the height of ramie, and the height decreased along with the increase of the concentration. Ethephon has no significant influence on the height of ramie in the first harvest season, whereas it decreased the diameter of ramie in the second and third harvest season to a certain extent. Paclobutrazol has no significant influence on the diameter of ramie in three harvest seasons of the year. Ethephon increased SPAD of ramie leaf in the first harvest season, but decreased SPAD of ramie leaf in the second and third harvest season. However, Paclobutrazol increased SPAD of ramie leaf in the first and second harvest season, whereas it has no significant influence on the indexe in the third harvest season.2. Determine the quality of fiber related indexes such as ramie fiber fineness, fiber breaking strength, fiber breaking elongation rate and so on. The results showed: Ethephon and Paclobutrazol reduced the ramie fiber fineness. Ethephon decreased ramie fiber fineness in the second and third harvest season significantly, whereas only Ethephon in the concentration of 400 mg/L decreased ramie fiber fineness in the first harvest season significantly. The fiber fineness decreased along with the increase of the concentration of Paclobutrazol. Ethephon in the concentration of 400 and 600 mg/L in the first harvest season and Paclobutrazol in the concentration of 150 and 200 mg/L in the third harvest season increased the fiber breaking strength. Ethephon and Paclobutrazol has no significant influence in the second and third harvest season. Only Ethephon in the concentration of 200 mg/L and Paclobutrazol in the concentration of 100 and 150 mg/L decreased the fiber breaking elongation rate significantly.3. Determine the resistance of plant related indexes such as POD activity, MDA content, Pro content. The results showed: Ethephon and Paclobutrazol increased POD activity of ramie leaf. Whereas Ethephon has no significant influence on MDA content of ramie leaf. Paclobutrazol decreased MDA content of ramie leaf in the second and third harvest season significantly. Only Ethephon in the concentration of 100 mg/L increased Pro content of ramie leaf significantly. However, Paclobutrazol has no significant influence on the indexe.