小果油茶表型多样性分析

在小果油茶全分布区内,选择有代表性的18个居群为研究对象,对其种实、花及叶的23个表型性状进行统计分析,结果表明:小果油茶的居群内及居群间均存在广泛的表型变异,随环境的变化表现出较强的表型可塑性。小果油茶叶、花及种实形状大小存在显著相关关系,可以从中选择重要及关键的表型性状作为测定的主要依据。小果油茶表型性状与生态地理因子有一定的相关关系,且不同性状受地理生态因子影响也不同,其中花性状最大,而种实和叶相对较小。UPGMA聚类结果表明,18个小果油茶居群可分为4个类群,且按较明显的地理区域特征进行聚类。从系统聚类图和主成分排序图比较来看,绝大多数居群在2种聚类方式中保持一致,说明二者均能较好地区分小果油茶不同居群的亲缘关系,为小果油茶的种质资源收集和良种选育奠定基础。     

不同山丹居群在保定的生长特性分析

对25个居群的山丹在保定地区的物候期、生长期特性进行了调查分析。结果表明,不同山丹居群的物候期存在明显差异。萌芽期和开花期最早的为辽宁居群,最晚的为易县和邯郸居群,萌芽期相差37～39 d,开花期相差将近3个月。25个居群的不同生长发育阶段(花蕾发育期、花期天数、生长周期)所需的时间长短不一。不同居群山丹生长曲线基本一致,均为慢-快-慢的生长趋势。相关分析表明纬度与山丹的萌芽期、现蕾期、始花期、末花期、果熟期、枯萎期之间均呈极显著负相关。山丹的自然物候期也存在明显早、晚差异,这为百合育种提供了良好的资源。     

异质生境对二型花柱植物雪地报春花性状分化的影响

该研究以生长在新疆北部的二型花柱植物雪地报春(Primula nivalis)为研究材料,对7个低海拔(1 657~2 013m)森林居群和7个高海拔(2 400~2 700m)草原居群的花型比例进行调查,对花部特征进行检测,并对长、短花柱植株在不同海拔居群的花性状分化进行了比较研究,以揭示该类群植物的演化与环境的关系。结果表明:(1)在高海拔草原居群中长花柱植株比例高于短花柱植株。(2)比较草原和森林生态系统中的雪地报春居群,长花柱花形态特征间存在显著差异,但短花柱花形态特征间的差异不显著。(3)高海拔草原居群中长花柱花的花冠筒长度、雄蕊长度、雌雄蕊距离、雌雄异位程度以及雌雄蕊空间位置是导致花性状分化的主要因素。(4)在草原居群中,长花柱花的雄蕊、雌雄异位程度及花冠口至雄蕊距离的变化减少了长短花柱花间的互补式对应性。研究认为,在异质生境中长花柱花性状的变化是导致该物种长短花柱花性状分化的主要因素。     

新疆东天山地区宽刺蔷薇居群表型多样性分析

对新疆东天山地区6个宽刺蔷薇（Rosa platyacantha）居群进行叶片、花序、果实、种子等11个表型性状的遗传多样性分析,结果表明：宽刺蔷薇各表型性状无论在居群间还是在居群内均表现出显著或极显著差异,存在丰富的表型多样性。6个居群11个性状的平均表型分化系数为27.50%,表明居群内多样性较居群间多样性更为丰富。各表型性状平均变异系数为16.51%,离散程度相对较低。对表型性状进行的变异系数多重比较和主成分分析均显示,果实相关性状的变异是造成宽刺蔷薇表型变异的主要来源。性状相关性分析进一步发现,生殖生长与前期的营养生长并无明显相关关系。聚类分析结果表明,6个宽刺蔷薇居群的表型性状并没有严格依地理距离聚类,而是受到遗传因素与环境条件特别是海拔因子的共同影响。     

秦巴山区野百合表型多样性

为揭示秦巴山区野百合天然居群的表型变异,对该地区17个野百合天然居群花、叶的8个质量性状和21个数量性状进行了观测。结果表明：野百合在秦巴山区适应性强、分布范围广,而且大多生长在海拔705~1913 m 的高山;表型性状变异丰富;上部叶片长与纬度存在显著正相关,柱头宽、上部叶片长与海拔高度存在显著正相关,下部叶间距与年降水量存在显著正相关,花梗长和上部叶片长与年均温度存在显著负相关;17个野百合天然居群被系统聚类为巴山和秦岭2大组。该研究结果为进一步开展野百合遗传育种、保护生物学的研究奠定了基础。     

山丹不同居群花粉形态研究

为掌握山丹居群在孢粉学方面的遗传多样性,在扫描电子显微镜下对25个居群的山丹花粉进行了形态观察,结果表明:山丹花粉粒形态为单花粉粒,极面观为椭圆体,具单萌发沟。不同居群的花粉粒在大小、网眼直径、萌发沟宽、P/E值和外壁纹饰等方面存在不同程度的差异,且居群间花粉性状的变异大于居群内的变异,最大变异系数达25.52%。     

云南滇龙胆居群表型多样性及其与环境关系研究

为揭示滇龙胆天然居群表型变异程度和变异规律,以云南省5个区域天然分布的20个野生居群400个单株20个表型性状指标为调查研究对象,并用变异系数、Shannon-Weiner多样性指数和巢式方差分析对滇龙胆居群间和居群内的表型变异进行分析,用相关性分析对滇龙胆表型性状与地理气象因子间的变异格局进行分析,用类平均聚类法对20个滇龙胆居群进行分类.结果表明:5个区域的滇龙胆以楚雄地区变异最大,变异系数为39.8%,变异最小的是昆明地区,为31.4%;不同居群的20个表型性状变异程度差异明显,变异系数在14.4%～91.8%之间,平均为40.4%,20个居群的平均变异为26.8%～37.0%;滇龙胆地理居群的表型分化较高,20个性状居群间的分化系数平均为73.14%,变化范围为36.03%～91.94%,居群间变异高于居群内;滇龙胆20个表型性状的总的多样性指数平均为2.547,5个不同分布区域多样性指数存在差异,最大为楚雄(1.271 4),最小为玉溪(1.266 7);表型性状变异受经度和降雨量影响较大,与纬度、海拔和温度相关性不显著;通过UPGMA聚类,滇龙胆被分成3个组,性状的表型特征并没有依地理距离而聚类....     

西藏喜马拉雅紫茉莉野生居群果实形态变异

为了明确不同种源喜马拉雅紫茉莉野生种质资源的果实形态差异,在西藏选取了16个居群,测量了8个果实性状,分别进行了单因素方差分析、主成分分析、聚类分析和相关性分析,为喜马拉雅紫茉莉遗传多样性的评价和种质选育提供依据。结果显示：（1）8个果实性状的平均值在不同居群存在差异,八宿县怒江山居群（TNC2）的总苞筒长、总苞裂片长和宽、果长、果形、百粒重均最小,其他居群未表现出明显的规律性;9个居群均以果纹路的变异系数最大,多数居群以果宽或果长变异最小。（2）总体上看,8个性状的变异系数在8.58%~25.57%之间,其中总苞裂片宽变异最大（25.57%）,而果宽变异最小（8.58%）;各性状的F值在12.180~134.761之间,均表现为差异极显著,表明8个性状在不同居群间均存在明显差异。（3）主成分分析显示,果长和总苞裂片大小是造成各居群间果实表型差异的主要因素。（4）根据果实性状,16个居群分为两大支,聚类结果与各居群的地域分布并无关联。（5）除总苞裂片宽与经度呈显著负相关关系外,经度、纬度和海拔对8个果实性状不存在显著影响。     

宁夏枸杞(Lycium barbarum)花器官形态多样性与品系间识别研究

该研究以42份宁夏枸杞(Lycium barbarum)为材料,对其中5个品系来自3个不同采集日期样品的花部性状进行了观察,同时对宁夏枸杞42个品系的16项花器官形态学指标进行了测定,并采用组间单因素方差分析法、主成分分析法和聚类分析法对宁夏枸杞种内的花部形态差异进行了研究。结果表明:宁夏枸杞花器官性状差异较大且多样性丰富,组间单因素方差分析表明宁夏枸杞花部性状在不同时间内采集无显著差异,即宁夏枸杞的花器官形态具有一定稳定性,因此可选用花器官形态作为区分宁夏枸杞种内不同品系的鉴别指标;主成分分析表明有关花瓣外缘色泽、花瓣正-背面脉络、花瓣形状、花瓣背部色泽、花喉色泽、雌雄蕊位置6个花部性状的累积贡献率达到84.791%,在宁夏枸杞品系的分类中起到了主要作用;聚类分析表明在欧式距离为7.5处可将枸杞的42个品系分成五类,能够将宁夏枸杞进行区分。该研究筛选出了能反映宁夏枸杞花器官形态差异的6个主要指标,并将42份宁夏枸杞分为五类,初步建立了宁夏枸杞种内品系间的形态学鉴别方法,可为宁夏枸杞的形态学研究及品系鉴定等提供依据。     

缙云山草珊瑚(Sarcandra glabra)天然居群结实特征的变异性研究

对缙云山草珊瑚8个天然居群结实特征的20项表型性状的变异性进行了研究,结果表明:各表型性状在居群内与居群间都存在很大的变异性,其中种实产量、果序数和果序分枝的变异程度较高,而果实和种子的特征指数变异程度较低,同类性状果实的变异程度要大于种子;平均变异系数最大的性状是四分枝果序百分比(1.477),最小的是种子长宽比(0.041);变异程度最大的居群是居群6(0.564),最小的是居群4(0.292);各居群间除果序分枝总数差异不显著、果序数和二分枝果序百分比差异显著外,其它17项表型指标均达到极显著水平,表明缙云山草珊瑚各居群间已经发生了明显的形态分化;居群内和居群间变异分别占总变异的60.7%和39.3%,说明居群内变异是表型变异主要来源,但居群间变异也不容忽视;欧氏距离聚类将所有居群划归为两大类群,主要与居群的群落类型与干扰程度有关;表型性状的Pearson相关性聚类显示草珊瑚同类性状在表型分化过程中具有很强的相关性。     

Characteristics of the membranes of the pellicle of the ciliatePseudomicrothorax dubius

Summary The membranes of the pellicle of the ciliatePseudomicrothorax dubius are investigated using thin section electron microscopy and freeze-fracture replicas. The plasma membrane is covered by a surface coat and is connected to the outer alveolar membrane by short, sometimes branched, bridges. The inner alveolar membrane is coated on both sides. The epiplasm lies in intimate contact with the cytoplasmic surface of this membrane, and there is a corresponding deposit on the other surface. This deposit is regularly striated.The epiplasmic layer and the alveoli are interrupted at sites of cytotic activity,e.g., the attachment sites of trichocysts, the cytoproct, and the parasomal sacs. The striated deposit ends where the epiplasm ends, indicating a direct relationship between these two epimembranous layers.There is a deposit along the sides of the first part of the tip of the trichocysts, and in this region the trichocyst membrane is free of intramembranous particles.The membrane of the parasomal sacs has a coat on both surfaces. That on the extraplasmic surface is similar to the surface coat of the plasma membrane. The origin of the cytoplasmic coat is unknown. The cytotic activity of these sacs is indicated by their highly irregular profiles.     

The early development of the tail and the transformation of the shape of the nucleus of the spermatid of the domestic fowl,Gallus gallus

Summary The differentiation of the spermatid, especially in reference to the formation of the flagellum, and transformation of the shape of the nucleus was investigated in the domestic fowl.In the early stage of the spermatid, a prominent Golgi apparatus appears around the centrioles. The Golgi vesicles then surround the axial-filament complex which develops from the distal centriole. These vesicles fuse to form continuous membrane at the earliest stage of flagellar formation, and in the succeeding stage Golgi lamellae are attached to the plasma membrane of the developing flagellum. From these observations, it is assumed that Golgi apparatus may be a source of the membrane system of the flagellum.The microtubules distributed around the nucleus form the circular manchette. The anterior region of the nucleus with the manchette is cylindrical in shape and the posterior region without it remains irregular in shape. When the circular manchette has been completed, the whole nucleus acquires a slender cylindrical shape. The circular manchette then changes into the longitudinal manchette. The nuclei of spermatids without a longitudinal manchette are abnormal in shape. In view of these observations it is assumed that the nuclear shaping of the spermatid may be accomplished by circular manchette and the maintenance of shape of the elongated nucleus by longitudinal manchette.The authors wish to thank Mr. Takayuki Mori for his helpful suggestions and technical advices     

Characterization of the composition of the aqueous humor and the vitreous body of the eye of the frog Rana temporaria L

This study aimed to analyze the aqueous humor (AH) and the vitreous body (VB) of the eye of the adult frog Rana temporaria L. as a representative species of amphibians, which lead a semi-terrestrial life. The presence of collagen, albumin, uric acid and electron donors was shown in both media; however, there are slight differences in their concentrations. To determine collagen, a spectral-fluorescent probe, cyanine dye, was used. The presence of collagen in AH of the frog was found at the first time. The total content of electron donors (ascorbic and uric acids, tryptophan, and tyrosine) in VB and HA was roughly estimated at ~ 1.5 × 10^− 4 mol/L. Both VB and AH absorb light in similar UV regions. The total protein and albumin contents in AH were found to be somewhat higher than those in VB. The uric acid content was at an equally low level in both intraocular media. It is supposed that the similarity of VB and AH compositions shown in this work is due to some exchange between VB and AH contents in the course of accommodation. The role of intraocular fluids in physiological functions of the eye and in protecting the retina against UV light is discussed.     

Observations on the permeability of the choriocapillaris of the eye

Summary The choriocapillaris is a fenestrated capillary bed located posterior to the retinal pigment epithelium. It serves as the main source of supply to the photoreceptors, retinal pigment epithelium, and other cells of the outer retina. The permeability of these capillaries to intravenously injected ferritin (MW — approx. 480,000; mol. diam. 11 nm) was examined in the mouse, rabbit, and guinea pig, each of which is characterized by a different type of retinal vascularization. In all three species, the bulk of the ferritin remained in the capillary lumina, where it appeared to be blocked at the level of the diaphragmed fenestrae. Some ferritin was present in endothelial cell vacuoles. The results confirm previous work on the rat choriocapillaris and indicate that the barrier function of the choriocapillary endothelium is present even among species in which the retinal circulation differs significantly.Supported by NIH grant EY03418