Genetic characterization of anemone-type chrysanthemum (Chrysanthemum morifolium) using floral morphology and SRAP markers

An appreciation of the genetic diversity retained in the gene pool of anemone-type chrysanthemums is needed to drive further genetic improvement of this commercially important ornamental species. Here, a panel of 67 accessions was characterized with respect to both floral morphology, assessed using a set of 12 inflorescence-associated traits, and to genotype, using sequence-related amplified polymorphism (SRAP) fingerprinting. Abundant variation and a high level of broad-sense heritability (>88%) were revealed for all traits except number of tubular floret lobes. Of the possible 66 pairwise inter-trait combinations, 37 proved to be significantly correlated. A principal component analysis of the trait data showed that the first four principal components explained ~78% of the variance; meanwhile a hierarchical clustering analysis revealed a number of discrete groups reflecting the various cultivated types, but was not predictive of provenance. The SRAP genotyping employed 22 primer combinations and generated 238 informative fragments. A moderately high level of the Jaccard's similarity coefficient (mean 0.67) was calculated for the examined panel. A hierarchical clustering analysis based on the genotypic data revealed four groups, which were clearly reflective of cultivated type; moreover, a comparison of the within-cluster means for each of the two key anemone-related traits—tubular floret length and tubular floret length/style length—showed that the genotype-based clusterings were associated with the anemone levels, albeit imperfectively. A principal coordinate analysis showed that the first two coordinates accounted for about 14% of the total variation. In summary, the present study adds new understanding of the genetic diversity present in the anemone-type chrysanthemum gene pool, and the findings will lay the foundation for implementing a genotype/phenotype association strategy to reveal the genetic and molecular basis of floral form in this valuable ornamental species.     

黄蒿和大籽蒿与两个园林小菊砧穗组合对生长和开花的影响

为了探究黄蒿(Artemisia annua)和大籽蒿(Artemisia sieversianae)作为砧木嫁接菊花的效果,拓展菊花嫁接的砧穗组合,本研究以园林小菊钟山粉韵和钟山紫辰为接穗,黄蒿和大籽蒿为砧木,比较4种砧穗组合嫁接对嫁接株的成活和发病、生长特性(冠幅、冠丛周径、砧木茎粗、最大根长、接穗干重、根干重、总...     

非洲菊组织培养中La3+的应用初探

 以非洲菊‘Sunbird’品种的花托、幼叶、幼芽为外植体, 研究不同浓度La³⁺对愈伤组织形成、生长、幼芽分化增殖的影响。结果表明, 低浓度La³⁺对花托愈伤组织形成、生长及芽的分化有促进作用,最佳处理浓度为10 mg/L , 处理浓度大于10 mg/L 时抑制芽的分化, 并明显引起褐化。La³⁺对离体叶片愈伤组织形成生长的促进作用亦随处理浓度的提高而增大, 但愈伤组织的褐化率也增大, 最佳处理浓度为15 mg/L。幼芽的增殖系数在La³⁺ 0～50 mg/L 范围内随浓度的提高而增大, 50 mg/L 时最大, 达20. 8 , 但浓度大于30 mg/L 时增殖过程易出现玻璃化苗并引起叶畸形, 增殖的最佳浓度为30 mg/L。     

菊花F1代舌状花耐寒性遗传变异与QTL定位

以菊花‘南农雪峰’ב蒙白’的F1代为材料,利用电导率结合Logistic方程计算盛花期舌状花的低温半致死温度（LT50）,分析其耐寒性的遗传变异,在此基础上开展QTL定位研究。结果表明,该F1群体舌状花的LT50在﹣8.92 ~ 1.31 ℃之间,变异系数为43.60%,近似正态分布,为多基因控制的数量性状,且存在一定程度的偏母性遗传和超亲分离现象。主基因 + 多基因混合遗传模型分析表明,该F1群体舌状花耐寒性无主基因控制。复合区间作图法共检测到6个QTL与菊花舌状花的耐寒性显著相关,分布在‘南农雪峰’遗传图的X2、X4连锁群和‘蒙白’遗传图的M2、M11、M33连锁群上,LOD值介于2.61 ~ 3.29之间,加性效应为﹣1.67 ~ 1.78 ℃,单个QTL可以解释耐寒性变异的贡献率为6.01% ~ 9.94%,均为微效QTL。     

切花小菊主要分枝性状的配合力与遗传力分析

切花小菊的分枝性状是其株形和观赏品质的重要构成因素。研究切花小菊主要分枝性状的配合力,为杂交亲本合理组配提供依据。通过4 × 3不完全双列杂交,分析了7个切花小菊亲本及其F1群体的总侧芽数、一级分枝数、一级分枝长度、一级分枝角度、二级分枝总数、二级分枝长度、二级分枝角度,共7个分枝性状的配合力效应和群体遗传参数。除总侧芽数主要受非加性效应控制外,其余6个分枝性状均主要受加性效应影响。各亲本在分枝性状上的一般配合力（GCA）,以及不同组合的特殊配合力（SCA）和总配合力（TCA）差异较大。‘Monalisa’除一级分枝数的一般配合力为负值,其余各性状的均为正值,是培育疏散型新品种的优良亲本。‘Qx-021’（除二级分枝总数）和‘Qx-096’各分枝性状的一般配合力均为负值,是紧凑型新品种的优良亲本。杂交组合‘Qx-021’בQx-098’、‘Qx-081’בQx-098’的一、二级分枝数的总配合力较高,其余5个性状的总配合力均为负值,是选育紧凑型切花小菊的优良组合。7个分枝性状的广义遗传力均很高（73.81% ~ 94.41%）;除总侧芽数（1.88%）外,各分枝性状的狭义遗传力均在60%以上,受环境影响较小。     

菊花新品种———国庆盆栽小菊系列

 国庆盆栽小菊新品种‘霞妃’、‘水晶宫’、‘金陵晚霞’、‘金陵赤心’、‘金陵国黄’、‘金陵红星’经自交种子辐射诱变、实生选育或常规杂交选育而成。株高15～40 cm, 冠幅均匀且较大, 分枝性强,长势旺盛, 花色艳丽, 初花期9月上中旬, 盛花期9月下旬或10月初, 适于盆栽, 满足国庆用花需求。     

菊科植物原生质体融合研究进展

 原生质体融合是转移目标性状, 特别是那些多基因控制或尚未克隆目标基因控制的性状的一种很有潜力的方法。菊科植物中原生质体融合研究主要集中在向日葵属(Helianthus) 、菊属(Dendranthema) 、莴苣属(Lactuca) 等少数几个属, 主要围绕抗性改良、雄性不育材料的获得、多倍体诱导、育种中间材料的创造等方面展开研究。本文对历年来菊科植物原生质体融合方面的研究作一综述, 并对存在的问题和改进措施进行了探讨。     

菊花新品种———秋花型盆栽小菊系列

 秋花型盆栽小菊新品种‘钟山橙光’、‘钟山红枫’、‘钟山黄托桂’、‘钟山国黄’、‘钟山白露’、‘钟山粉妆’经实生选育获得。6个品种的株高均在25～40 cm, 冠幅均匀, 介于45～60 cm之间, 分枝性强, 长势旺盛, 花色艳丽, 初花期10月初, 盛花期10月中、下旬, 适合于盆栽应用。     

Reproductive characteristics of Opisthopappus taihangensis (Ling) Shih,an endangered Asteraceae species endemic to China

Opisthopappus taihangensis is an endangered species endemic to China and represents an important genetic resource for chrysanthemum improvement. We describe here its basic reproductive characteristics. The anthers are tetrasporangiate and the anther wall is composed of an epidermis, endothecium, middle layer and tapetum. The middle layer is lost by the microspore tetrad stage, and the tapetum disintegrates at the trinucleate pollen stage. Meiosis in the microspore mother cells is of the simultaneous type, and the tetrad is tetrahedral in shape. Mature pollen grains have three germinal apertures, two sperm nuclei and one vegetative nucleus. The in vitro pollen germination rate is only ∼10%. The ovule is anatropous, dual-integument, tenuinucellatae and the development of the embryo sac follows the Oenothera pattern. The archesporial cell below the nucellus epidermis functions as the megaspore mother cell and forms a linear tetrad. The embryo passes through a globular, heart and torpedo stage before maturing into a cotyledon embryo. The endangerment of O. taihangensis may be associated with low reproductive capacity, as a consequence of poor pollen viability.     

早期断奶对湖羊羔羊生长性能及胃肠道发育的影响

为研究湖羊羔羊28日龄断奶是否可行,本试验选用48只初生重[(3.51±0.57)kg]接近的湖羊公羔,随机均分为2组,分别为早期断奶组(28日龄断奶)和对照组(56日龄断奶)。从7日龄开始补饲开食料,60日龄同时逐渐换生长料。分别在42、56、70、84日龄测定羔羊体重,每组屠宰6只,测定各胃室重量、容积以及各肠段重量、长度。结果表明:1)42、56、70、84日龄2组羔羊体重差异不显著(P0.05),各时间段平均日增重2组差异不显著(P0.05);2)瘤网胃、瓣胃的重量、容积,瘤网胃相对重量(占活体重、胃肠道重、胃重百分比),瘤网胃相对容积(占胃容积百分比)在42、56日龄早期断奶组显著高于对照组(P0.05);3)除70日龄结肠重外,其余各肠段重量、长度在各日龄2组间无显著差异(P0.05)。综合以上各项指标认为,本试验条件下,28日龄断奶可促进湖羊羔羊胃肠道早期发育,28日龄断奶可行。