Study On Pruning Of Oil Peony Paeonia Ostii ‘Feng Dan’

In order to explore reasonable pruning methods of oil-used peony,reveal the spatial distribution structure and biomass accumulation and distribution of young`Fengdan’plants of different plant ages under pruning and shaping mode,and try to establish the most suitable model of yield equation,which aims to provide theoretical and practical basis for the cultivation system and industrialization development of oil-used peony,and has the potential to improve grain yield and achieve high yield.It is of great theoretical and practical significance.Effects of stubble height（15,10,and 5 cm）and stumping time（November and February）on growth,photosynthetic physiology,and fruiting of 3-year-old seedling of Paeonia ostii were studied based on randomized complete block design.The 3-year-old‘Feng Dan’plant with the same quality was planted at the end of October each year from 2013.In2017,the‘Feng Dan’born in 3,4,5,and 6 years under the pruning,After planted,the pruning model of flat stubble for two consecutive years was carried out.The 6-year-old‘Feng Dan’who had been flat stubbled once after planted and the 6-year‘Feng Dan’,who had not been pruned,were used as the control group.The effect of the growth status and biomass allocation of young pruned‘Feng Dan’were studied to try to establish a description of a fitting model of the plurality of growth factor and yield.（1）The variance analysis result shows that there are extremely significant differences in plant growth indexes,photosynthetic parameters and chlorophyll content in leaf,and fruiting indexes of P.ostii among stubble height treatment groups,extremely significant differences in plant growth indexes and fruiting indexes of P.ostii among stumping time treatment groups in general,and no significant difference in other indexes.Overall,stubble height of5 cm and stumping treatment in November are beneficial to shaping plant type and enhancing photosynthetic efficiency of P.ostii,and can provide more favorable growth conditions for superior and high yield.（2）Compared with the same-age plants,the growth indexes of plants under pruning mode were higher than those of control group,and the difference was significant（p<0.05）;the plant under pruning mode was higher than that of control group,and the difference was significant（p<0.05）.The grain yield of 6-year plants under pruning mode could reach 2173.20 kg·hm^-2.The biomass and organ biomass of 6-year plants under pruning mode were higher than those of control group,and the difference was significant（p<0.05）.The minimum root-shoot ratio of 6-year plants under pruning mode was 107.9%and the biomass allocation can make the root to the ground part more transferred.In the pruning model,with the increase of plant age,the growth index,the fruit index,the total biomass and the biomass of all organs were increased,the root shoot ratio was decreased,and the biomass allocation was transferred more from the root to the fruit,and the distribution of stem and fruit biomass was increased gradually.The pruning can improve the‘Feng Dan’growth index,the accumulation of total biomass and the accumulation of biomass in various organs are increased,and the distribution of biomass could be more transferred to the fruit,and then the yield could be improved.（3）The yield prediction model was:Y=-314.422+2.622B+1.048H-1.093D with the goodness of fit R²=0.811,（B is plant age,H is height,D is crown width,and Y is the yield of per plant）.