| Lonicera maackii(Rupr.)Maxim.is the main landscaping plant in China,which has hi-gh ornamental value,medicinal value,good prospect of development and utilization,and high conservation value.For better protection and reasonable development and utilization of Lonicera maackii.In this paper,Lonicera maackii was used as experimental materials to cryopreserve the three germplasm resources of seeds,pollen and shoot tips.The best preservation method was found by comparing the changes of vitality and physiological indexes of materials before and after cryopreservation.The conclusions are as follows:1.The seeds of Lonicera maackii can be stored for a long time by cryopreservation.Due to the dormancy of the seeds,the seeds were soaked with gibberellin at concentration of 700mg/L for 24 hours to break dormancy before cryopreservation.When the seed is preserved by ultra-low temperature,the seed germination rate can reach 89%after the moisture content is 7%and ultra-low temperature treatment is adopted for slo-w-freezing and quick-freezing;Other through the seed conductivity,four kinds of enzyme activity,as well as the changes of the content of three kinds of permeability substances,the best method of ultra-low temperature preservation of Lonicera maackii seeds was selected:seed moisture content was kept in the range of 7%-11%,and cryopreservation was the best when slow freezing and quick thawing or rapid freezing and thawing solution was used.2.The pollen of Lonicera maackii can be stored for a long time by cryopreservation.The viability of pollen was determined by in vitro germination.The effects of different collection time,water content,thawing method and different preservation methods on the preservation efficiency of pollen were studied.The results showed that the best time to collect Lonicera maackii pollen is at about 13:30 on the day of flowering.In the cryopreservation,the pollen had the best storage effect after undried(moisture content of 13.04%),direct input of liquid nitrogen,and after thawing in tap water at 15 ℃ for 5 minutes,the pollen germination rate could reach 81.9%.In the preservation time of 360 days,the pollen preserved at-196℃ had higher germination rate,while the pollen at room temperature quickly inactivated,the pollen viability at 4℃,-20℃ and-80℃ showed a decreasing trend.3.The shoot tip of Lonicera maackii can be stored for a long time by cryopreservation.In this experiment,the cryopreservation system of Lonicera maackii shoot tip was established.The main step is to collect the stem segment in the growing period as the material,and after disinfection,to cultivate the sterile seedling.The aseptic stem segments with the length of 2-3cm shoot tip in the sterile seedling were cut as preculture materials.The culture was placed in a preculture solution with a sucrose concentration of 0.3 mol/L at 4℃for 3 days,and 2-3 mm long shoot tips were removed.After that,the shoot tip was treated with LS loading solution for 40 minutes,and then treated with PVS2 solution at 0℃for 40 minutes,replace the fresh protection solution and immediately put it directly into liquid nitrogen.The preservation time is 24 hours.After taking out the frozen tube containing the shoot tips,it was thawed in a 40 ℃ water bath for 70s,and quickly washed with unloading solution for 20 minuters,each time for 10 minutes.After washing,the shoot tips were inoculated on medium No.4,MS+KT 0.5 mg/L+NAA 0.1 mg/L+GA3 1.0 mg/L.The recovery culture conditions were cultured in a dark environment at 25℃ for two weeks and then transferred to normal light for cultivation.At this point,the survival rate of the shoot tip is up to 73%,subsequently,they were directly cultured into seedlings using the Lonicera maackii shoot tip tissue culture system. |
PDF Full Text Request