| 摘要: |
| 【目的】探究河南豫西低山丘陵地区不同经营世代及不同林龄人工刺槐林腐殖质浸提液对自身种子萌发和幼苗生长的影响，揭示在连续多代栽培下腐殖质对刺槐苗更新的影响，为刺槐多代连栽及可持续经营提供科学依据。【方法】选取刺槐不同经营世代及不同林龄的9种林分（编号为F1~F9）为研究对象，各设置3块样地进行基本林分调查，制备0.4 g/mL（C1，原液），0.2 g/mL（C2），0.1 g/mL（C3），0.05 g/mL（C4），0.025 g/mL（C5）不同林分腐殖质浸提液，进行刺槐种子萌发和幼苗生长试验，测定刺槐种子发芽率、发芽势、发芽速度指数、活力指数，胚根长、胚芽长、苗鲜质量、苗干质量，以及刺槐幼苗叶绿素a、叶绿素b、叶绿素总量、叶绿素a/b，根系SOD、POD、CAT活性等指标，采用GC MS技术分析不同林分乙酸乙酯腐殖质浸提液中的化合物质组成和相对含量。【结果】刺槐腐殖质浸提液会影响刺槐种子萌发及胚和幼苗生长，各指标在不同林分以及不同质量浓度间存在差异。大部分林分C1、C2和C3处理腐殖质浸提液对刺槐种子萌发和幼苗生长各指标具有抑制作用，C4和C5处理腐殖质浸提液对各指标呈低抑制作用或促进作用。化感综合效应指数表明，一代和三代刺槐林腐殖质浸提液对自身种子萌发和幼苗生长的抑制作用随着林龄增加呈下降趋势，二代林腐殖质浸提液对自身种子萌发和幼苗生长的抑制作用较强且稳定。从9种刺槐林分腐殖质浸提液中共检测出31种化合物质，且各林分中均以酯类物质相对含量较高；在三代林中，随着经营世代的增加化合物质种类呈上升趋势；异胆酸乙酯、4,4,6a,6b,8a,11,11,14b-八甲基-13-氧化十二碳二烯-3-乙酸酯、十八碳酸甲酯、2-［3-乙酰氧基-4，4，14三甲基雄甾-8-烯-17-基］丙酸和Z-5-甲基-6-二十一碳烯-11-酮5种化合物质在9种林分腐殖质浸提液中均被检测到。【结论】刺槐林腐殖质浸提液对自身种子萌发和幼苗生长具有一定的抑制作用，影响刺槐实生苗更新，但不同刺槐林分腐殖质浸提液的抑制程度有差异。 |
| 关键词: 刺槐 腐殖质 种子萌发 幼苗生长 化感效应 森林经营 |
| DOI： |
| 分类号: |
| 基金项目:国家重点研发计划项目“刺槐速生建筑材林高效培育技术研究”(2017YF0600503) |
|
| Effects of humus extracts from Robinia pseudoacacia forests on seed germination and seedling growth |
|
JING Rong,PENG Zuodeng,LI Yun,et al
|
| Abstract: |
| 【Objective】This study explored the effects of humus extracts on seed germination and seedling growth in artificial Robinia pseudoacacia forests at different ages with different management generations in the low mountain and hilly areas of western Henan,and revealed the effects of humus on seedling regeneration under continuous multi-generation cultivation to provide basis for multi-generation continuous planting and sustainable management of Robinia pseudoacacia.【Method】A total of 9 kinds of stands (numbered F1-F9) of Robinia pseudoacacia with different management generations and different forest ages were selected,and 3 plots were set up for basic investigation in each stand.After being extracted and filtered with distilled water in the laboratory,0.4 g/mL (C1,stock solution),0.2 g/mL (C2),0.1 g/mL (C3),0.05 g/mL (C4) and 0.025 g/mL (C5) humus extracts were obtained for seed germination and seedling growth tests.Seed germination rate,germination potential,germination speed index,activity index,radicle length,germ length,seedling fresh mass,seedling dry mass,contents of chlorophyll a,chlorophyll b,total chlorophyll and chlorophyll a/b,activities of root SOD,POD and CAT as well as other indicators were measured.The composition and relative content of compounds in ethyl acetate humus extracts from different stands were analyzed by GC-MS.【Result】The humus extract of Robinia pseudoacacia affected seed germination and growth of embryo and seedling.There were differences among different stands by different mass concentrations.The humus extracts of Robinia pseudoacacia treated with C1,C2 and C3 had inhibitory effects on seed germination and seedling growth in most stands,while the C4 and C5 treatments had less inhibitory effects or promoting effects.The allelopathy comprehensive effect index showed that the inhibition of humus extracts from the first and third generations on seed germination and seedling growth decreased with the increase of forest age,and the inhibition of humus extracts from the second generation was strong and consistent.A total of 31 compounds were detected from the humus extracts of 9 Robinia pseudoacacia stands,and esters had high relative content.In the three generation forests,the species of chemical compounds showed an upward trend with the increase of management generation.The compounds detected in all stands included ethyl iso-allocholate,acetic acid,4,4,6a,6b,8a,11,11,14b-octamethyl-13-oxodocosahydropicen-3-yl ester,methyl stearate,2-(3-acetoxy-4,4,14- trimethylandrost-8-en-17-yl) propanoic acid and Z-5-Methyl-6-heneicosen-11-one.【Conclusion】Humus extracts from Robinia pseudoacacia stands had inhibitory effects on seed germination and seedling growth of Robinia pseudoacacia and affected seedling regeneration with different inhibition degrees among stands. |
| Key words: Robinia pseudoacacia humus seed germination seedling growth allelopathy forest management |
