紫菜薹同源四倍体的诱导鉴定及特性研究

为获得优质、抗病的同源四倍体紫菜薹(Brassica campestris var. purpurea Bailey)新材料，使用0.2 g·L^-1秋水仙素溶液点滴二倍体子叶顶端分生组织，经形态和解剖学、细胞学鉴定筛选得到同源四倍体植株。通过对二倍体、四倍体植株农艺性状和营养品质分析发现：四倍体植株的株高极显著增高；开展度、叶片宽、叶柄长显著增加；叶片数极显著降低。营养品质方面，可溶性蛋白、花青苷含量显著增高；可溶性糖和纤维素含量极显著降低；硝态氮含量显著降低。光合特性分析发现，四倍体植株的净光合速率、胞间CO₂浓度、气孔导度、蒸腾速率均高于二倍体，表明四倍体更能适应强光。抗病性分析发现，四倍体受灰霉菌侵染后，菌斑面积小，颜色淡，具有更强的抗病性。     

芦笋四倍体诱导、倍性鉴定及生物学特性的研究

以南方主栽品种"井岗701"二倍体芦笋的露白种子和幼苗为试材,研究了秋水仙素浓度、处理时间及浸泡时的转速对芦笋四倍体诱导效果的影响,并对四倍体和二倍体芦笋的部分抗性和形态特征进行了比较。结果表明:以0.2%的秋水仙素浸泡露白种子6h效果最好,四倍体诱导率最高,为20%,但浸泡时的不同转速对四倍体诱导影响差异不显著;而用0.3%的秋水仙素连续滴苗4d,四倍体诱导率最高为18%;浸泡露白种子法比滴苗法诱导效果好;四倍体植株较二倍体更加粗壮,在抗热性和抗旱性方面也明显优于二倍体。     

豇豆四倍体的诱导及鉴定

用浓度为0.1%~0.3%的秋水仙素处理二倍体豇豆子叶期的茎尖生长点,获得同源四倍体(2n=4x=44),并对其进行形态学、细胞学、农艺学鉴定。结果表明:经0.2%秋水仙素处理4次获得同源四倍体的效果最佳,四倍体诱变率为2.809%;与二倍体相比,四倍体植株叶片、花器官、荚果等均表现巨大性,气孔密度和单个荚果种子数降低;用流式细胞仪进行倍性鉴定,豇豆二倍体DNA相对含量为250,四倍体为500,与根尖染色体鉴定结果一致。     

秋水仙素处理对芦笋“达宝利”四倍体诱导效果的影响

以芦笋“达宝利”露白种子为试材,秋水仙素(添加2%DMSO)处理浓度和处理时间作为诱导因子,设计多个梯度的正交实验,研究秋水仙素对芦笋四倍体诱导率的影响,以期获得最佳的芦笋多倍体诱导条件。结果表明:最佳的秋水仙素处理组合为0.15%的秋水仙素(添加2%DMSO)处理16h,诱导率高达28.33%;经鉴定发现二倍体芦笋的染色体数目为20条,而四倍体染色体数目为40条;与二倍体相比,四倍体芦笋植株粗壮、叶片长度和直径增加,气孔细胞密度减少,气孔细胞体积增大,叶绿体数目和叶绿素含量增加。     

鹤顶兰四倍体植株的诱导与鉴定

 以鹤顶兰原球茎为材料,使用秋水仙素进行了四倍体的离体诱导。结果表明,采用秋水仙素浸泡法可以诱导鹤顶兰原球茎发生倍性变化,含0.02%秋水仙素的“花宝一号”溶液浸泡处理6 d诱导率最高,达22.5%。细胞学鉴定发现,诱变成活植株中有3株为四倍体,其植株形态、气孔大小、气孔密度与二倍体存在差异,细胞核明显增大。     

穿心莲四倍体的诱导及其愈伤组织对肉桂酸胁迫的响应

以不同倍性穿心莲诱导的愈伤组织为试材,采用秋水仙素对穿心莲种子进行四倍体诱导,通过在穿心莲四倍体及二倍体诱导愈伤组织培养基中添加化感自毒物质肉桂酸进行共培养的方法,研究了肉桂酸对不同倍性穿心莲愈伤组织的褐化率、细胞鲜质量、超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性和丙二醛(MDA)含量的影响,以期为筛选穿心莲抗化感自毒物质的优良种质资源提供参考依据。结果表明:用0.05%的秋水仙素处理48h,穿心莲种子诱导成活率达89%,经过植株形态、气孔及染色体数目检测,确定了穿心莲四倍体株系PZ-1、PZ-2、PZ-3、PZ-4、PZ-5、PZ-6、PZ-7、PZ-8,其染色体数为4x=96,二倍体为2x=48。在1.00mmol·L^-1肉桂酸的愈伤组织诱导培养基中培养7d,穿心莲四倍体愈伤组织的褐化率和MDA含量较二倍体低,而愈伤组织鲜质量、SOD、POD、CAT活性较二倍体高,显示四倍体较二倍体具有对肉桂酸更强的抵御能力,其中四倍体PZ-7表现出较显著的优异性状。     

叶片气孔保卫细胞周长用于鉴定黄花蒿倍性的研究

以二倍体、四倍体及经秋水仙素处理的黄花蒿植株为试材,采用整体透明技术制备黄花蒿叶片样品,对不同倍性植物的叶片气孔保卫细胞长轴长、短轴长及其周长进行考察,探讨气孔保卫细胞大小与植株倍性的相关性。结果表明:以10%氢氧化钾溶液为透明剂,透化时间为1.5h的透化效果最好;二倍体与四倍体植物的气孔保卫细胞长轴长、短轴长及其周长差异显著,其周长范围分别为57.19~70.33μm和83.36~91.99μm;利用二倍体与四倍体的周长分布在不同区间范围,可以对秋水仙素处理的黄花蒿植株进行快速的初步倍性鉴定。     

秋水仙素离体诱导同源四倍体青花菜

 以青花菜品种‘海兹’高频再生试管苗为外植体, 利用秋水仙素离体诱导四倍体。结果表明: 用含秋水仙素200 mg·L ^{- 1}的MS + 0.1 mg·L ^-1NAA + 6.0 mg·L ^{- 1} 6-BA液体培养基处理2 cm长的再生苗48 h, 每个外植体平均可产芽2.1个, 再生植株变异率为83.33% , 四倍体诱导率达79.17%。与二倍体相比, 四倍体植株叶片、花冠、气孔等均表现巨大性; 流式细胞仪倍性鉴定显示, 对照DNA相对含量为200, 四倍体再生植株为400。四倍体根尖染色体2n = 4x = 36。     

秋水仙素处理离体叶片获得皇家嘎拉苹果四倍体植株

采用皇家嘎拉苹果（Malus domestica Borkh．）离体新梢叶片作为外植体，研究了不同浓度的秋水仙素长时间处理（5 d）诱导四倍体的效率。结果表明，以不定芽再生培养基附加25 mg／L秋水仙素效果最好，最高在36．7％的叶片外植体上获得了四倍体植株。高浓度（75～200　mg／L）秋水仙素处理严重抑制组织的再生。采用流式细胞技术测定出诱变植株的细胞核DNA含量比对照高出一倍，确定了植株为四倍体。四倍体植株不仅在遗传上而且在外观形态上也明显区别于二倍体。四倍体植株已移栽于大田，并进行了嫁接育苗和大树高接。     

秋水仙素诱变薄皮甜瓜同源四倍体研究

为了获得四倍体薄皮甜瓜材料,研究薄皮甜瓜多倍体的特征特性,以二倍体薄皮甜瓜金美为材料,以0.2%、0.4%、0.6%的秋水仙素采用滴苗和浸种2种方法进行诱变四倍体试验,并通过染色体观察和细胞学鉴定对其进行倍性分析。结果表明,滴苗法比浸种法诱变率高,其中以0.4%秋水仙素滴苗诱变率最高,为6.67%;与二倍体相比,四倍体植株子叶和真叶长宽比变小,茎增粗,节间变短,花冠变大,果肉变厚,种子增宽,可育性降低,中心可溶性固形物含量增高;保卫细胞变大,气孔密度变小,保卫细胞内叶绿体数目增加;获得了同源四倍体材料。     

Antioxidant phytochemicals and gingerol content in diploid and tetraploid clones of ginger (Zingiber officinale Roscoe)

Fresh rhizomes of 18 diploid and tetraploid genotypes of Indian ginger, including commercial cultivars and experimental genotypes, were assayed for gingerol content and antioxidant activity. The tetraploid ginger type was derived from the respective diploid ginger by shoot tip culture. [6]-Gingerol was identified as the major pungent phenolic compound in all samples (mean 1354.78 ± 470 μg/g), while [8]- (mean 180.94 ± 45 μg/g) and [10]-gingerol (mean 234 ± 79 μg/g) occurred in lower concentrations. The total gingerol content of the tetraploid type was much higher than that of the respective diploid type and especially the [10]-gingerol. Both diploid and tetraploid types of the cv. Meghalaya Local contained the highest level of gingerol. At both ploidy levels, the genotypes showed significant differences in phenols and antioxidant activities. Correlation of total phenolics with different antioxidant assay at both diploid and tetraploid level was linear and strong to moderate. For genotypes at both ploidy levels, antioxidant activity (BCO) was determined especially by [6]-gingerol while [8]- and [10]-gingerol did not affect BCO. These results demonstrated that in the tetraploid types of ginger, the gingerol content and antioxidant activity were higher than in the diploid ones.     

In vitro induced tetraploid of Dendranthema nankingense (Nakai) Tzvel. shows an improved level of abiotic stress tolerance

The tetraploid of Dendranthema nankingense (Nakai) Tzvel. was induced by the colchicine treatment using nodal segments. Ploidy level was determined by an analysis of flow cytometry and chromosome counting. The morphological characteristics such as the stomata, leaves, flowers and pollen grains of the tetraploid were significantly larger than those of the diploid. The tolerance responses of the diploid and tetraploid were compared under the imposition of heat, cold, drought and salinity stress. Semi-lethal temperatures suggest that cold tolerance is improved by polyploidization, but the heat tolerance is reduced. Under drought and salt stress, the activity of peroxidase (POD) and relative water content (RWC) in the tetraploid were higher than those in the diploid. Accordingly its malondialdehyde (MDA) content maintained a lower level. The content of chlorophyll (a + b) in the tetraploid was higher, and decrease of its content was postponed in tetraploid compared with the diploid under salt stress. It suggested that polyploidization could alleviate oxidative stress, maintain good water balance and higher chlorophyll (a + b) content, thereby enhanced the drought and salt tolerance in colchicine induced tetraploid.     

白菜不同倍性材料间光合特性差异研究

 以白菜‘短白梗’的二、四倍体为材料, 研究它们的光合特性发现, 秋季晴天的Pn日变化四倍体与二倍体类似, 都呈单峰型曲线。短白梗四倍体中光合色素含量略高于二倍体, 但差异不显著, 叶绿素a /b比值在二、四倍体间差异也不显著。四倍体的叶绿体的长度和宽度均显著高于二倍体, 基粒片层加厚, 结构致密有序。     

甜瓜同源四倍体的创制及其初步定性研究

通过未成熟胚子叶的组织培养创造体细胞无性系变异,诱导出了齐甜1号的同源四倍体甜瓜,激素质量浓度以BA3.0mg/L为佳,加倍率为14.3%。对再生的同源四倍体及二倍体甜瓜植株进行了茎、叶、花、果实、种子的形态观察,及各项形态指标和主要品质指标的测定。结果表明:除果形指数变小外,四倍体植株的茎、叶、花、果实、种子各项形态指标的值均显著大于二倍体。同时,四倍体甜瓜维生素C、可溶性糖含量也显著高于二倍体。     

Analysis of effects of auxin on fruit size of tetraploid and diploid tomato fruits

Selfed and auxin-treated fruits of tomato (Lycopersicon esculentum Mill.) were obtained from tetraploid and diploid plants and compared to determine why selfed tetraploid fruits are smaller. Application of auxin to ovaries produced tetraploid fruits as large as normally set (selfed) diploid fruits but led to reduced fruit size in diploid fruits, reflecting a further potential for tetraploid fruit development. The selfed tetraploid fruits were found to be smaller because they had fewer cells per fruit. Cell size (diameter) at the end of fruit development was similar for all fruit types. DNA per cell did not closely match cell size during development, especially during the cell division stage. Protein per cell also failed to follow cell size. Protein per DNA showed one peak at around day 10 of fruit development and possibly a second one at day 30.     

不同倍性紫锥菊的性状比较及新种质的获得

采用同株系二倍体、四倍体、八倍体紫锥菊进行大田栽培试验,比较不同倍性紫锥菊的营养生长、生殖生长及多酚类成分指标,八倍体母株种子萌发后通过根尖染色体计数法进行倍性分析,以期为遗传基础理论研究和育种提供更多的材料选择。结果表明:随着倍性增加,株高变矮,叶长宽比和舌状花长宽比变小;每株分枝数以四倍体最高;一年生时二倍体的头状花序数和总花序数最多,显著高于四倍体和八倍体;二年生时四倍体的头状花序数和总花序数最多,显著高于二倍体和八倍体;二年生采收数据紫锥菊四倍体全株产量较八倍体高232.6%,二倍体全株产量较八倍体高187.1%;四倍体和八倍体的地上部、地下部总多酚含量、绿原酸含量、菊苣酸、单咖啡酰酒石酸含量均显著较二倍体高,八倍体地上部和地下部绿原酸含量、地上部菊苣酸含量显著高于四倍体;八倍体子代实生苗倍性鉴定得到五倍体和非整倍体。对紫锥菊而言,八倍体倍性太高,其产量和品质的综合性状不具备优势,但在作为种质资源方面具有价值;四倍体表现优良,较二倍体效益高;获得的五倍体和非整倍体材料,在生产和作为遗传改良桥梁种方面具有价值,是紫锥菊整倍性和非倍性材料创建的有益补充。     

不同倍性西瓜果实维生素C含量比较研究

以10个西瓜品种的二倍体及其人工诱导的同源四倍体、三倍体为材料,研究不同倍性西瓜成熟果实Vc含量的差异及果实发育过程中Vc含量的变化。结果表明,不同倍性西瓜中Vc含量差异较大,9个品种三倍体或四倍体的Vc含量高于二倍体(P<0.05);不同倍性西瓜果实中Vc含量变化规律基本相同,幼果期较高、果实膨大期较低、成熟期较高,且呈近似"V"型变化曲线。其峰值的出现顺序为2X、3X、4X,倍性越高,其峰值出现越晚。不同染色体倍性西瓜果实Vc含量较高的时期均为成熟期。     

秋水仙素浸根法诱导优质小型西瓜四倍体试验初报

用不同浓度的秋水仙素对优质小型西瓜进行浸根和滴苗处理诱导四倍体,结果表明,随着浸根所用秋水仙素浓度和时间的增加.四倍体诱导率有增加的趋势,最高诱导率达到了20.0%,比滴苗处理高出11.3%.将加倍的四倍体果实与二倍体果实进行比较,四倍体果实皮厚增加,瓤质变硬,结籽数下降.