Study On Breeding Technology Of Ulmus Elongata

Ulmus elongata L.K.Fu et C.S.Ding is a rare and endangered tree species in China,which belongs to the national secondary key protected wild plants.At present,the population of Ulmus elongata is very rare,and the population distribution range is narrow,only scattered in 5 provinces and regions,and the natural regeneration is poor.Therefore,it is urgent to study the breeding technology of Ulmus elongata,which is of great significance to protect Ulmus elongata and expand its population.In this study,sowing propagation,cutting propagation and field transplanting of Ulmus elongata were studied,and the best breeding techniques of Ulmus elongata were analyzed and summarized.The research results are as follows:(1)Sowing and propagation technology of Ulmus elongata was studied.The optimal conditions for seed emergence of Ulmus elongata were studied by different sowing time,different covering substrate and different covering thickness.The best technology of seed propagation of Ulmus elongata was studied by using different seedling substrates,different fertilization treatments and plant determination observation.The results showed that the best sowing time of Ulmus elongata seeds after maturity was to pick and sow at the same time.Saw dust was the best covering substrate.The best coverage thickness was 3mm.After transplanting,the best substrate was the mixture of humus soil and garden soil in a ratio of2:1.Compound fertilizer and potassium fertilizer were the best during seedling growth.The seed sowing time of Ulmus elongata is about April 23,and the seed will break out on April27,and the seed will start to emerge on May 3,and the seedlings will basically come out on May 13,and the seedling growth will be in full bloom in July and August,and the high growth will basically stop on October 30.(2)The cutting propagation technology of Ulmus elongata was studied.Through orthogonal experimental design,the effects of different hormone types,different treatment concentrations and different treatment time on the cutting rooting effect of Ulmus elongata were studied.The results showed that the rooting type of Ulmus elongata was callus.The three factors all had significant effects on the rooting effect of Ulmus elongata cuttings.The primary and secondary effects were as follows: hormone type > treatment time > treatment concentration;The optimal cutting combination of Ulmus elongata was as follows: 200mg/L ABT for 2h.(3)To study the field transplanting technology of Ulmus elongata,select different altitudes to carry out field planting experiments on Ulmus elongata,and summarize the best field transplanting environment of Ulmus elongata under artificial intervention conditions.The experimental results showed that the most suitable field transplanting site of Ulmus elongata was Langhekou labaping of Niutoudian protection station with an altitude of950 m,and the survival rate was as high as 91.16%.The net growth of seedlings ranged from14-101 cm,and the height growth of most seedlings was about 35 cm.