【作者】 陈姗姗；

【导师】 宋述尧；

【作者基本信息】 吉林农业大学 ， 蔬菜学， 2007， 硕士

【摘要】 本文以山芹菜（Spuriopimpinella brachyara（Kom．）Kitag．）种子为材料，通过测定种子物理特性、种皮的透水性、种胚发育状况及种子各分离组分的生物抑制等试验，探讨了山芹菜种子的休眠原因，同时采用秋播以及植物生长调节剂和层积处理结合室内外发芽试验，寻找打破山芹菜种子休眠的方法，并测定层积过程中的种子主要贮藏物质含量的变化及一些关键酶类活性的变化，了解种子解除休眠的过程与物质代谢变化的相关性。本文初步探索出种子休眠机理和解除山芹菜种子休眠的催芽方法，为保护山芹菜的野生资源的生物多样性、发展人工栽培提供了一条可行的途径，主要研究结果如下：1．种子具有独特的物理性状，种子含水量较高，达到61.845％；种子中大粒，种子一些主要物理参数与含水量之间存在极显著相关关系；当年采收的山芹菜种子生活力较高，但种子存在生理休眠现象。2．通过对山芹菜种子的解剖学观察发现，采收时种胚的形态和结构尚未发育完全，种胚极小，仅占全种子的3.36％，不具备萌发能力，属于胚的形态后熟型休眠。3．完整种皮和去除种皮的山芹菜种子都能达到饱和吸水量，说明山芹菜种子种皮透水性较好，不是引起种子休眠的原因。4．采用系统溶剂法得到山芹菜种皮和胚乳提取物的四种分离相，其中以甲醇相的抑制活性最强，对白菜种子发芽率和胚根长度的抑制活性均表现为：胚乳＞种皮，说明甲醇是提取山芹菜种子各部分发芽抑制物质的最佳溶剂，发芽抑制物质的存在是山芹菜种子休眠的主要原因。5．种子经单纯的暖温（20℃）层积处理不能破除种子休眠，始温为20℃的变温处理破除种子休眠效果也不理想，低温处理和越冬层积具有破除种子休眠作用，低温层积（0—5℃）的条件较其它层积条件下的种胚生长发育好，完成了子叶、胚根和胚芽的分化，种胚通过生理后熟，低温层积阶段还有利于生活力的保存和发芽能力的提高，是最佳的处理方法。6．采用不同浓度的三种植物生长调节剂预处理后结合低温层积处理，试验结果发现：解除山芹菜种子休眠的最佳综合技术为：250mg／LGA₃浸种24小时后低温层积100天可使种子发芽率达60％左右，发芽势较高，且腐烂率低，基本上解除了山芹菜种子休眠，生产上建议使用。7．在低温层积阶段，随着山芹菜种子细胞含水量的增加，种子吸涨后蛋白酶活化，贮藏蛋白质被分解为游离氨基酸；粗脂肪随着层积的进行逐渐降解为脂肪酸；随着淀粉酶活性的增强，淀粉转化为可溶性糖的速度加快。氨基酸含量和淀粉酶活性的变化与发芽率存在多项式正相关关系，还原糖和粗脂肪含量与发芽率存在线性负相关关系；蛋白质、糖类和粗脂肪的相互转换，为种子萌发提供了重要的能量来源。更多还原

【Abstract】 In this text, the seeds of Spuriopimpinella brachyara （Kom.）Kitag. were selected as the trial material, and through the experiments such as seed physical properties, water permeability of seed coats, development of embryos and the biotic measurement of the methanol extract of different parts of seeds, meanwhile adopt fall sowing, PGR and stratification treatments to find out the methods that could break the dormancy of seeds, then determined the change of content of main storage substances and activity of some key enzymes in order to find out the relationship between process of dormancy and change of material metabolism. This article had researched the mechanism of dormancy and found out the methods that could break dormancy effectively, provided a feasible approach to protect the diversify wild resources of Spuriopimpinella brachyara （Kom.）Kitag and develop artificial cultivation. The results were shown as follow:1. The seed possessed unique physical properties and had high moisture content reached 61.845%, it had very remarkable relationship between some mainly physical properties and moisture content. The seed had high seed viability, but existed physiology dormancy phenomenon.2. Through to anatomy observation of the seeds ofSpuriopimpinella brachyara （Kom.）Kitag. disclosed: the seed had a tiny embryo with a rich endosperm and the embryo was not fully differentiated when the seeds harvested, only occupied 3.36% of seed, it belonged to a type of embryo morphology dormancy.3 Both integrated seed and without seed coat of Spuriopimpinella brachyara （Kom.）Kitag. could achieve the saturated moisture content, showed that the seed has a good water permeability, the seed coats were not the factor caused the dormancy of the seed4. By the use of system solvent separation method, four kinds of organic phase of the extract getting from the seed coats and endosperms were obtained: methanol phase inhibited the germination of cabbage seeds strongly, and the inhibitory effect of the extracts from endosperm was stronger than that from the seed coat, it was obvious with high concentration. Therefore, methanol is a good kind of organic solvent to dissolve much inhibitors in some degree, illustrated that the seeds existed germination inhibitors were the main reason caused dormancy of the seeds.5. The warm temperture（20℃） stratification had no effect on breaking dormancy, changing temperature stratification also was not the ideal method, cold temperature stratification and stratificated outdoor under low temperature were good enough to break the dormancy. The growth and development of embryos under the stratification condition（4±1℃）were better than that under the other conditions, the embryos had accomplished the physiological after-ripening and preserved stronger ability of sprouting.6.With the experiments of adopting three different kinds and concentrations of PGR pretreatment combine stratification resulted: soaking the seeds in GA₃ for 24 hours ,and then stratifying seeds under low temperature（4±1℃） for 100 days was the best technique to break the dormancy of seeds of Spuriopimpinella brachyara （Kom.）Kitag. and the germination percentage could achieve 60%, which had high germination capacity and low rotten percentage, relieved the dormancy of the seeds of Spuriopimpinella brachyara （Kom.）Kitag on the whole.7.In the course of the cold stratification, the moisture content went on increasing, the protein decompose to free amino acid, and the rough fat degraded to fat acid; The speed of starch transforming to sugar accelerated when the activity of amylase enhanced. It had a remarkable positive polynomial relationship between the free amino acid、the activity of amylase and the germination percentage; the content of reducing sugar、the rough fat and the germination percentage had a remarkable negative linear relationship. The transformation between the protein, rough fat and sugar could provide big energy for the sprouting of seeds.更多还原