摘要
单性木兰(Kmeria septentrionalis)隶属于木兰(Magnoliaceae)科单性木兰(Kmeria Dandy)属,为中国一级重点保护植物,仅分布于贵州的茂兰国家级自然保护区和广西的木论国家级自然保护区。经测定,单性木兰千粒重为121.591g,种子净度为64.24%,含水量为18.027%,用1%四唑染色法测定种子生活力为74.33%。为研究喀斯特立地因子水、Ca2+和土壤pH值对单性木兰种子发芽的影响,把单性木兰种子置于15、20、25、30℃4个恒温处理和白天夜晚温度分别20/15℃、25/15℃、30/15℃的3个变温培养箱中进行发芽,结果表明:不同温度条件对单性木兰种子发芽的启动没有显著差异,都在15d左右开始发芽,对其发芽率的影响是显著的,在温度为15、20℃条件发芽率较高,尤其是在变温(白天/夜晚)20/15℃条件下发芽率最高,为43.33%;用4个Ca2+含量浓度为0.1%、0.4%、0.7%、1.0%对单性木兰种子进行发芽处理,结果表明:Ca2+浓度0.7%时,种子发芽最高,为26.67%,但都低于清水对照的发芽率;聚二乙醇(PEG)模拟水分胁迫试验,PEG-6000浓度为1%、2.5%、5%、7.5%、10%、15%、20%、25%、30%的溶液进行发芽,结果表明,当PEG的浓度大于2.5%时,单性木兰种子发芽率明显下降,且发芽率均低于对照;盐酸和氢氧化钠调节pH分别为6.0、6.5、7.0、7.5、8.0的溶液模拟土壤的不同,对种子进行发芽处理,结果表明,当pH达到7.0～7.5时,单性木兰的发芽率达到最大值44.44%,所以最适合单性木兰种子发芽的土壤pH为7.0～7.5。
Kmeria septentrionalis, the member of Magnoliaceae and endangered plant only locates in Maolan na- tional Nature Reserve of GuiZhou province and Mulun national Nature Reserve of GuangXi province,was listed first-grade State protection plant. Through inspecting,1 000 grain seed weight was 121. 591 g,seed purity was 64.24% and seed moisture was 18. 027 %, seed vitality tested by TTC （0.1% ）was 74.33 %. In order to study the effect of water, Ca2＋ and soil pH on Kmeria septentrionalis seed germination, Kmeria septentrionalis seeds were put at 15,20,25,30 ℃ constant temperature and poikilothermic treatment, ie day/night was 20/15,25/ 15,30/15 ℃. Results indicated that Kmeria septentrionalis seed germination percentage was relative high at 15℃and 20 ^（2 ,Kmeria septentrionalis seeds germination was the highest at poikilothermic treatment（20/15℃ ）, 43.3%. Different Ca2＋ concentration had different effect on Kmeria septentrionalis seeds germination, When Ca2＋ concentration was 0.7% ,Kmeria septentrionalis seeds germination was the highest,26.67% ,but lower than that of ck. PEG stress had obvious effect on Kmeria septentrionalis seeds germination, Kmeria septentrionalis germination decreased obviously to lower than that of ck when PEG concentration was higher 2.5%. Using hydrochloric acid and sodium hydroxide to adjust pH to 6.0,6.5,7.0,7.5,8.0 imitating the different soil pH to treat Kmeria septentrionalis seed. Results showed that： when the pH 7.0 -7.5 ,Kmeria septentrionali~ seeds germination rate was up to the maximum,44.44%, this outcome indicated that the most suitable pH for Kmeria septentrionalis seed germination was 7.0 - 7.5.
出处
《种子》
CSCD
北大核心
2010年第3期4-8,共5页
Seed
基金
国家重点基础研究发展规划项目专题(973计划)(2006CB4032-06)
国家"十一五"科技支撑计划项目(2006BAD03A1006-2
2006BAC01A09-1)
贵州省科技计划项目(黔科合NY[2009]3052)
贵州大学自然科学青年科研基金项目(贵大自青基合字(2007)063)
关键词
温度
水分
pH
钙离子浓度
种子发芽特性
单性木兰
temperature
water
pH
Ca2＋ concentration
seed germination
Kmeria septentrionalis
