Effects Of Substrate Ratio And Three Kinds Of Growth Regulators On The Growth Of Container Seedlings Of Magnolia Wufengensis

Magnolia wufengensis is a new species discovered by a research team led by Prof.Ma Lvyi of Beijing Forestry University in Wufeng County,Hubei Province in 2004,which has important scientific research value.In this study,we studied the effects of different Substrate ratio on the growth and physiological characteristics of container seedlings of Magnolia Wufengensis and screened out the best seedling growth media for the container seedlings in order to provide a good growth and physiological condition for the Magnolia Wufengensis dwarf studies.And we studied the effects of different growth regulators on the dwarfing effect of Magnolia Wufengensis container seedlings and found the species and concentration of growth regulators with the best dwarfing effect.Nursery culture in Beijing,as well as research on the dwarfing effect of Magnolia Wufengensis container seedlings is of great significance.The main research results are as follows:1.Substrate ratio promoted the growth of container seedlings of Magnolia Wufengensis.In each ratio substrate,when the ratio of peat and sand was 50%:50%,the indicators of container seedlings of Magnolia Wufengensis were better than other treatments.Compared with the control,the seedling height increased by 41.84%and the diameter of ground increased by 23.02%,no significant difference in height to diameter ratio,and the root growth,seedling quality index,net photosynthetic rate,light use efficiency and chlorophyll content of container seedlings of Magnolia Wufengensis increased significantly.The proportion of peat and sand is 50%:50%,which can significantly reduce the relative conductivity of the container seedlings of Magnolia Wufengensis,2.The application of chlorocholine chloride(CCC)promoted the growth of container seedlings of Magnolia Wufengensis.When the concentration of CCC was 1500 mg/L,the plant height and ground diameter growth of container seedlings of Magnolia Wufengensis had significant effect.Compared with the control,the seedling height increased by 55.65%,the ground diameter increased by 21.55%,and 1500mg/L CCC treatment caused the root length,root surface area,root volume,seedling quality index,net photosynthetic rate,and Light energy utilization and chlorophyll content increased significantly.The application of CCC can significantly reduce the relative electrical conductivity of Magnolia Wufengensis container seedlings.The reduction of relative electrical conductivity is more pronounced when the concentration of CCC is 500 mg/L and 1000 mg/L.3.The uniconazole treatment had obvious dwarfing effect on container seedlings of Magnolia Wufengensis,which significantly reduced the height,ground diameter and ratio of height to diameter compared with the control.The average height of seedlings decreased by 30%,the diameter of ground decreased by 16%,and the ratio of height to diameter decreased by 17%.Uniconazole treatment significantly reduced the total root length of container seedlings,but promoted the accumulation of root biomass,stem biomass and seedling quality index.The 300 mg/L seedling quality index was higher than other treatments.The application of uniconazole can improve the net photosynthetic rate,light energy utilization rate and chlorophyll content of container seedlings of Magnolia Wufengensis,and the treatment effect of 100 mg/L is the most obvious.Uniconazole treatment can reduce the relative conductivity of Magnolia Wufengensis container seedlings,and the relative electrical conductivity is the smallest under 200 mg/L treatment.4.Ethephon treatment had obvious dwarfing effect on container seedlings of Magnolia Wufengensis,and dwarfing effect was most obvious under 500 mg/L treatment.Compared with the control,the seedling height decreased by 42.35%,the ground diameter decreased by 36.02%,and the height-to-diameter ratio had no significant difference.Ethephon treatment significantly reduced the root development,seedling quality index and chlorophyll content of container seedlings of Magnolia Wufengensis,but had no significant effect on net photosynthetic rate and light energy utilization efficiency of container seedlings.Ethephon treatment can reduce the relative conductivity of container seedlings.Under 500 mg/L treatment,the relative conductivity of stems of Magnolia Wufengensis container seedlings was the smallest.