【作者】 王军玲；

【导师】 梁国鲁；

【作者基本信息】 西南大学 ， 花卉学， 2008， 硕士

【摘要】 鸡冠花(Celosia cristata L.)属于苋科(Amaranthaceae)青葙属(Celosia),一年生草本植物。其花序顶生,色彩鲜艳明快,既可盆栽、露地栽培观赏,也可用作切花和干花材料,具有极高的观赏价值。同时也具较高的药用和食用价值。本研究以鸡冠花种子为试材,对鸡冠花离体快繁进行系统研究,并在此基础上,结合染色体工程技术,利用秋水仙素进行八倍体诱导,以期得到具有价值的鸡冠花八倍体新种质,并为以后的倍性育种奠定基础。主要研究结果如下:鸡冠花离体快繁体系的研究结果表明——最适种子消毒方法:洗涤剂浸泡10 min,自来水冲洗30 min,75%乙醇消毒30s,0.1%升汞消毒10 min(滴加1～2滴1%的吐温-20),无菌水冲洗4～6次;初代诱导鸡冠花的芽分化最佳培养基:MS+1.0 mg/L6-BA+0.2 mg/LNAA,增殖系数1.17;继代增殖以不定芽为材料的最佳培养基:MS+1.0mg/L6-BA+0.1mg/LNAA,增殖系数为1.43;以茎段为材料产生不定芽的最佳继代培养基为MS+1.0mg/L6-BA+0.02mg/LNAA,增殖系数为4.67;最适生根培养基:1/2MS+IBA0.4mg/L,生根率95%,移栽成活率在90%以上:以MS+1.0mg/L6-BA+0.2mg/LNAA诱导鸡冠花试管开花,诱导开花率最高。在组织培养的基础上,以秋水仙素为诱变剂,采用浸泡法和混培法对鸡冠花进行多倍体的诱导研究。结果表明:浸泡法以0.15%秋水仙素溶液处理36h效果最好,诱变率为23.3%;混培法以添加0.1%的秋水仙素的培养基处理15d为好,诱变率为16.7%。对八倍体(2n=8x=72)和四倍体(2n=4x=36)鸡冠花植株外部形态特征、气孔密度、保卫细胞大小等进行对比研究。结果显示:八倍体植株的叶片增厚、叶子变长、叶形指数变大,分别是四倍体的205%、144%、116%;八倍体气孔密度明显下降,为四倍体的49%;保卫细胞增大,长、宽分别为四倍体的170%和164%;保卫细胞内叶绿体数明显增多,为四倍体的178%;叶绿素含量增加,为四倍体的145%。经方差分析,八倍体与四倍体的叶长度、厚度、气孔密度、保卫细胞长度、宽度和叶绿体数目存在极显著差异。叶长度、叶片厚度、气孔密度、保卫细胞的大小和保卫细胞内叶绿体数目可作为鉴别四倍体和八倍体鸡冠花的重要参数。对八倍体和四倍体鸡冠花植株进行抗性对比研究。其抗寒性研究结果:5℃低温处理24h后,四倍体的丙二醛(MDA)含量为八倍体的208%,达到极显著水平,八倍体抗寒能力强于四倍体。抗旱性的研究得出:四倍体外渗率为八倍体的203%,经20%PEG处理后,四倍体植株株外渗率为八倍体182%;处理后四倍体丙二醛含量为八倍体的226%,达到极显著水平,八倍体鸡冠花抗旱能力强于四倍体。更多还原

【Abstract】 Celosia cristata L.is an annual herb,which belongs to the Celosia of Amaranthaceae.The Inflorescence of Celosia cristata L.is acrogenous,and its colour is bright.It is used as a pot culture or a open culture.In addition,it can be made into cut flower or dry flower materials,Meanwhile,it has extremely high ornamental,medicinal and edible value.In the study the seeds of Celosia cristata L.were used as explants in tissue culture for rapid propagation.and then based on tissue culture and used chromosome engineering,the methods of inducing Celosia cristata L.octaploid were tested by colchicines.In order to obtain the valuable germplasm which can be used in the polyploidy breeding for future.The main results are the following:The result showed:The seeds were dipped in the scour 10 minutes and washen 30min by tap water,then sterilized 30 seconds by 75%alcohol and 10min by 0.1%HgCl₂,rinsed 4～6 times by sterilized water,the appropriate medium for inducing the differentiation on bud of the first culture about Celosia cristata L.was MS+1.0mg/L6-BA+0.2mg/LNAA,Coefficient of multiplication was 2.17;MS+6-BA 1.0 mg/L +NAA 0.1 mg/L and MS+6-BA 1.0 mg/L +NAA 0.02 mg/L were the favorable proliferate medium for adventitious buds obtained from budsand stems,2.43 and 4.67 were their coefficient of multiplication;the best rooting medium was 1/2 MS+IBA 0.4 mg/L,the induction rate was 95%,The surviving rate of plantlets was above 90%after transplanted to the ground.,hormones have effect on the flowering in vitro of Celosia cristata L.,the best medium was MS+6-BA 1.0 mg/L +NAA 0.2 mg/L.On the base of Celosia cristata L.tissue culture,the inducing polyploidy of Celosia cristata L.was carried out by colchicines.Two methods were used.The tetraploid plantlets were obtained by immersing buds in various concentrations of colchicine solution,and inoculating buds in the mediums containing colchicine.The result indicated that the way of immersing buds on colchicine was better.It was the most effectively induced by immersing buds of Celosia cristata L.in 0.15% colchicine solution for 36h,which had the most tetraploid plantlets,inducing ratio was 23.3%.Buds of Celosia cristata L.were inoculated in the medium contained 0.1%colchicine for 15 days,had the most tetraploid plantlets,inducing ratio was 16.7%. The leaf,stoma,guard cell and chloroplast characteristics of octaploids（2n=8x=72）and tetraploids（2n=4x=36）Celosia cristata L.were compared.The result indicated that octaploid leaves were thicker and lengther,leaf index was bigger.The thickness leaves,length,leaf index of octaploid were 205%,144%and116%of those of the tetraploid respectively.The octaploid of Celosia cristata L.with fewer stoma densitie which was 49%of that of the tetraploid.The guard cell of the octaploid was evidently bigger,The guard cells’ length of octaploid was 170%of that of the tetraploid and the width was 164%.The numbers of chloroplast in the guard cells increased evidently and there was 178%of that of the tetraploid.Content of chlorophyl of the octaploid was 145%of that the tetraploid.By the analysis,between octaploid and tetraploid,leaf thickness,leaf length,stoma density, guard cell size,chloroplast number were mighty significantly different.So,leaf thickness,leaf length, stoma density,guard cell size and chloroplast number can be used to identify tetraploid and octaploid of Celosia cristata L..The resistance was measure and compared between the octaploid and tetraploid.the result of cold resistance that to treated 24h under the 5℃,the MDA content of tetraploid was 208%that of octaploid,compared with control variance analysis,their variance were extreme level of significance,then It shows that the octaploid cold resistance of Celosia cristata L.are stronger than the tetraploid.Research of the drought resistance indicated that behind the treatment of 20%PEG,the exosmosis rate of electrolyte of treated plants of tetraploid and its check plants were 182%,203% those of octaploid respectively,MDA content of the tetraploid’s treated plants was 226%that of octaploid,all were extreme level of significance.Accordingly,the determination result of two physiological index indcated that the octaploid drought resistance of Celosia cristata L.are stronger than the tetraploid.更多还原