Studies On Agronomy Regulation And Mechanism Of Above-ground And Below-ground Growth Of Ramie (Boehmeria Nivea L.)

In this research, the ramie variety—Tri-1, which were breeded by the Institute ofRamie Research of Hunan Agricultural University, was selected to serve asexperiment materials. Pot exeperiment and field exeperiment were conducted to studythe effect and mechanism with nitrogen applying in different levels, concentration ofPP₃₃₃, harvest period on ramie. The main research results were as follows.1. It can promote the growth of ramie below-ground and significantly improveramie roots and subterranean stem weight as the nitrogen concentration in the10mmol/L～20 mmol/L and the PP₃₃₃ concentration in the 50 mg/kg～150 mg/kg scope.The weight of below-ground of ramie showed a downward trend with the extensive ofthe harvest period.2. Fertilizering nitrogen could significantly improve the weight of tare and rawlinen of ramie, and the differences among each level of nitrogen is remarkable; Theweight of bast skin and raw linen of ramie were significantly inhibited by PP₃₃₃. Theweight of tare and raw linen of ramie were first increased by maximun and thendecreased and reached at the maximum when the first time of havest at May 30, andthe highest yield is appear at the second season ramie of every treatment.3. Fertilizering nitrogen could significantly improve the root-top ratio of ramie,and reached at maximum cap when the concentration of nitrogen at 15 mmol/L; PP₃₃₃could significantly improve root-top ratio of ramie, and the higher the concentrationsare, the more obvious effects are. Different harvest periods, the root-top ratio of ramieof the first harvest at 10th May and at 9th June were significantly higher than the first harvest at 20th May and the first harvest at 30th May.4. Fertilizering nitrogen could significantly improve ramie root activity, andreached at maximum when the concentration of nitrogen is at 15 mmol/L; PP₃₃₃ couldsignificantly improve root activity of ramie, and reached at maximum when theconcentration of PP₃₃₃ is at 100 mg/kg. The root activity of ramie was dropped afterreaching maximun; Ramie root activity decreased significantly with the extension ofharvest period. When ramie growth of different treatments is at stage second season,root activity is highest.5. POD activity was first increased and then decreased after the maximum withthe concentration increased, and reached at maximum when the concentration ofnitrogen at 15 mmol/L. POD activities of first season ramie of different treatment arehigher than that of second season ramie. PP₃₃₃ can improve ramie roots POD activity,and the activity is at the peak under the concentration of 100 mg/kg. After rearching atmaximum, the activity decreased with the concentration increased; with the extensionof hearvest period, ramie roots POD activity is gradually declining.