摘要
樟子松是我国北方荒漠化地区生态环境建设的重要树种,近年来樟子松人工林出现不同程度的衰退问题,自然更新障碍则是限制樟子松人工林发展演替的关键因子。为探究樟子松人工林自然更新的限制因子,通过不同沙埋深度及不同种子处理方法等室内发芽试验,对樟子松种子萌发出苗的影响进行研究。结果表明：1）在沙埋深度为0-3.00 cm范围内,无沙埋时樟子松种子萌发出苗能力最强,随着沙埋深度的增加,种子萌发出苗能力不断降低,沙埋深度显著影响种子的萌发和出苗;2）4℃低温冷藏保存的种子比常温保存和-18℃低温冷冻保存的种子,在萌发出苗上更具优势;3）种子经25～30℃温水浸种24 h处理后,在出苗率和出苗时间等方面优于55-60℃热水浸种和不浸种处理,表现为樟子松种子较为适宜的处理方式。其研究可为解决樟子松人工林自然更新障碍问题提供参考和借鉴,并为樟子松人工育苗提供技术支撑。
[Background] Pinus sylvestris var. mongolica is an important species for ecological environment construction in the desertified regions of northern China. There has been declines in P.sylvestris plantations,barrier on regeneration has been the key factor limiting the succession of P.sylvestris plantations. [Methods] To explore the limiting factors for natural regeneration of P. sylvestris plantations,experiments in the laboratory were carried out on the effects of sand burial（ depth of 0. 25,0. 50,1. 00,1. 50,2. 00 and 3. 00 cm in a container simulating the sand land） and seed processing（ No-soaking,soaking in 25- 30 ℃ warm water,and soaking in 55- 60 ℃ hot water） on the germination and seedling emergence of P. sylvestris. The seeds were collected from the Yulin of Shaanxi Province,stored at room temperature,4° C refrigeration and- 18 ℃ frozen. The data were analyzed by two-way ANOVA. [Results]1） In range of 0- 3. 00 cm,the rate of seed germination and seedling emergence was 68. 9% that reached the highest with no sand burial,and decreased with the increase of burialdepth,there was about 20% seeds germinated but no seed emerged under 3. 00 cm depth. Sand burial caused the germination time increased,the average germination time was only 4 d with no sand burial,the average germination time reached 15 d under 2. 00 cm depth. 2） The seeds stored at 4 ℃ were more superior to those at the room temperature and frozen storage of- 18 ℃,for a higher germination and emergence percentage and a shorter emergence time. Low temperature preservation was helpful to increase the seed vigor in the shallow sand burial depth（ 0- 1. 50 cm）,but the different seed corresponded to different germination and emergence of the optimal temperature range. 3） The germination quality of seeds soaked in 25- 30 ℃ warm water were superior to those soaked in 55- 60 ℃hot water and no-soaking,for a higher germination and emergence percentage,emergence rate and a shorter emergence time. Too high soaking temperature inhibited seed germination,the seed germination rate of soaking in 55- 60 ℃ hot water at 1. 50 cm depth was only 0. 3% and had a long emergence time as 16 d under 1. 50 cm depth. [Conclusion] 4 ℃ storage and 25- 30 ℃ warm water soaking are appropriate seed treatment for P. sylvestris. The results can be used to provide the references to solve the problem of natural regeneration and provide technical support for the artificial breeding of P. sylvestris plantations.
出处
《中国水土保持科学》
CSCD
北大核心
2016年第6期86-93,共8页
Science of Soil and Water Conservation
基金
北京林业大学科学技术研究项目"呼伦贝尔沙地人工固沙植被稳定性研究"(2015-03)
国家林业局公益性行业科研专项"中国沙地补充考察与沙地志编研"(201304325)
关键词
樟子松
萌发出苗
沙埋
种子处理
Pinus sylvestris var
mongolica
germination and seedling emergence
sand burial
seed processing
