Effects Of Cultivation Conditions On The Photosynthetic Characteristics And Growth Of Heracleum Moellendorffii Hance

Heracleum Moellendorffii Hance is not only an important source of wild plant,but also an important part of forest resources,and plays an important role to the ecological balance of wild environment.Heracleum Moellendorffii Hance has a high medicine food homology,wild Heracleum Moellendorffii Hance has been picked a lot,leading to the wild resources reduced year by year.In order to protect and rationally develop and utilize Heracleum Moellendorffii Hance and the germplasm resources are continuously used,the phenomenon of artificial breeding and cultivation of Heracleum Moellendorffii Hance is started.However,Heracleum Moellendorffii Hance belongs to the wild vegetable,and its living environment and wild environment are obviously different in the artificial cultivation.The changes of the growth,photosynthetic characteristics and quality of Heracleum Moellendorffii Hance are not known under artificial cultivation.The experiment studied the effects of cultivation density,cultivation mode,nitrogen form,temperature,light and soil moisture for the growth,photosynthesis,and quality of Heracleum Moellendorffii Hance,and try to provide the scientific basis for the cultivation of Heracleum Moellendorffii Hance.The main results were as follows:?1?With the cultivation density decreasing,the growth of the plants,the thick stems,the dry weight of the ground,the light saturation points and the maximum net photosynthesis increased.Low density was favorable for accumulation of dry matter and strong plant,and high density increased cell yield with and medium cultivation density was beneficial to the accumulation of vitamin C and flavonoids content.The plant height,chlorophyll content,apparent quantum efficiency and water utilization efficiency were higher in high density?60 cm×10 cm,D10?than other cultivation densities.?2?Ridge cultivation way was significant to the accumulation of dry matter and the accumulation of vitamin C by increasing the light saturation point and maximum net photosynthetic rate,and ridge tillage cultivation way decreasing Heracleum Moellendorffii Hance expansion degree and increasing the plant height and water use efficiency was beneficial to the accumulation of medium yellow ketone leaf.?3?The nitrogen treatment was beneficial to the increases of plant height and the accumulation of dry matter content in the ground and underground parts,improving the stomatal conductance,transpiration rate and increasing the content of soluble sugar,chlorophyll b and vitamin C content in the leaves,reducing the concentration of intercellular CO₂ and transpiration rate,and nitrate nitrogen?N1?and amide nitrogen?N3?were all beneficial to reduce the degree of expansion and improve its net photosynthetic rate.Nitrate nitrogen?N1?and ammonium nitrogen?N2?were beneficial to improve chlorophyll a and soluble protein content.Ammonium nitrogen?N2?treatment is beneficial to raising the stem of the Heracleum Moellendorffii Hance.?4?The suitable tempetature of 20?was beneficial to the growth of the Heracleum Moellendorffii Hance,and the temperature of 15²0?was conductive to the accumulation of soluble protein and vitamin C of leaves.When the temperature was 20?,chlorophyll b content and net photosynthetic rate was high,and plant height and leaf area was the highest.The content of soluble protein and vitamin C in the leaves was at higher levels and significantly higher than other processing temperature on the average daily temperature of 15²0?.?5?The light transmittance of 80⁸5%increased the growth of plant and beneficial to the accumulation of soluble sugar,soluble protein and vitamin C and light saturation and leaf area was highest point,maximum leaf area,and plant height and dry weight above ground were at higher lever.?6?When the water content of the substrate was 60⁶5%,the high,leaf area,dry weight and net photosynthetic rate of the Heracleum Moellendorffii Hance plant were the highest,and the water content of the substrate of 60⁶5%was beneficial to the accumulation of soluble sugar and soluble protein.In conclusion,it is suggested to adopt ridge cultivation method in production,Medium density treatment?equivalent to 75,000 seedlings per hectare?,environmental temperature control between 15²0?,the transmittance is controlled at 80⁸5%,the soil moisture content is controlled between 60%⁶5%,nitrogenous fertilizer is suitable for artificial cultivation.