Inhibition of Camellia japonica Pollen Tube Growth by Maltose

Various oligosaccharides were studied with regard to their effecton the in vitro growth of Camellia japonica pollen tube. Sucrose,raffinose, melezitose, cellobiose, turanose and isomaltose,especially the first four, promoted pollen tube growth, whilemaltotriose, trehalose, gentiobiose, palatinose, melibiose,lactose and lactulose had little effect. Maltose strongly inhibitednot only the tube growth on sugar-free medium but also sugar-stimulatedgrowth, except in the case of sucrose stimulation. Glycosidaseactivities toward the growth-stimulating oligosaccharides weredetected in the extract of sucrose-grown pollen, but the activitiesof -glucosidase and -galactosidase were much lower than thoseof ß-fructosidase and ß-glucosidase. Maltosesuppressed the increase in UDP-glucose level of the glucose-grownpollen but not that of the sucrose-grown one. These resultssuggest that maltose acts, directly or indirectly, somewherein the pathway from glucose to UDP-glucose via glucose-1-phosphate,but does not interfere with the direct conversion of sucroseto UDP-glucose. (Received December 1, 1984; Accepted May 24, 1985)     

Occurrence of Theanine in Camellia Japonica and Camellia sasanqua Seedlings

Three additional structural gene loci (Acp, EstB-1 and Pgm, encoding the enzymes acid phosphatase, esterase B and phosphoglucomutase, respectively) were identified in commercial and research-maintained lines (155) of Agaricus bisporus. The addition of these new marker loci effectively increases the total number of biochemical loci now available in A. bisporus by 60%. Allozyme variability at all eight structural gene loci (Aat, Acp, Adh, EstB-1, Gpt, Pep-1, Pep-2 and Pgm) was used to classify the lines into only 37 genotypic classes out of more than 3 million possible. A recalculated UPGM (unweighted pair-group method) cluster analysis, based on coefficients of similarity for all lines examined, is presented. The limited genetic diversity in this germplasm collection, as evidenced by linkage disequilibrium between loci and a lack of fit to Hardy-Weinberg expectations, commercially remains untapped.     

Shoot and root organogenesis of Camellia sasanqua

In vitro-derived shoot tips, (10 mm) taken from primary cultures of Camellia sasanqua L., were evaluated for organogenesis when cultured on a half-strength MS medium supplemented with various concentrations of NAA, IBA, BA and GA₃. Maximum shoot proliferation and growth for juvenile and mature tissue was obtained when 0.54 M NAA, 8.8 M BA plus 14.4 to 28.9 M GA₃ was added to the culture media, with a pH between 4.5 and 5.0. In vitro-derived shoots (20 mm) from mature C. sasanqua Day Dream and juvenile C. sasanqua cultures initiated roots in vitro after immersion in 2.5 mM IBA for 30 min. Sixty percent of the mature shoots and 90% of the juvenile shoots initiated roots within 3 weeks of treatment with IBA.Abbreviations MS Murashige and Skoog (1962) - IBA lH-indole-3-butanoic acid - BA N-(phenyl-methyl)-lH-purine-6-amine - GA₃ gibberellic acid - kinetin N-(Z-furanyl-methyl)-lH-purine-6-amine - NAA l-naphthaleneacetic acid - L Linear - Q Quadratic     

Storage in an Organic Solvent as a Means for Preserving Viability of Pollen Grains

Pollen grains of Lilium auratum, Lilium longiflorum, Camellia sasanqua and Impatiens balsamina were soaked in various kinds of organic solvents such as acetone, benzene, petroleum benzine, benzyl alcohol, butanol, ethanol, methanol, isopropanol, diethyl ether, petroleum ether and choroform, and stored at 4-6 C for 24 hr. All pollen grains except in benzyl alcohol showed evidence of viability, and grains which had been stored in acetone, benzene, petroleum benzine, diethyl ether, petroleum ether and chloroform produced longer pollen tubes than grains of fresh pollen, especially Camellia sasanqua, whose pollen grew tubes 3 times as long as those of a control. Lilium auratum pollen grains had retained their viability after 80 days in acetone, benzene, petroleum benzine, diethyl ether and petroleum ether, and generative nuclei in pollen thus stored divided to form 2 sperm nuclei in artificial culture.     

茶梅品种资源的收集保存、鉴定评价及种质创新

综述了国内外茶梅品种的收集保存、鉴定评价及种质创新工作,其中上海市农业生物基因中心自2002年起,共收集国内外茶梅品种80余种,建立品种资源基地并对其进行了鉴定评价,筛选出3个适于上海地区的品种,并登录新品种1个。     

Unraveling Entropic Rate Acceleration Induced by Solvent Dynamics in Membrane Enzymes

Enzyme catalysis evolved in an aqueous environment. The influence of solvent dynamics on catalysis is, however, currently poorly understood and usually neglected. The study of water dynamics in enzymes and the associated thermodynamical consequences is highly complex and has involved computer simulations, nuclear magnetic resonance (NMR) experiments, and calorimetry. Water tunnels that connect the active site with the surrounding solvent are key to solvent displacement and dynamics. The protocol herein allows for the engineering of these motifs for water transport, which affects specificity, activity and thermodynamics. By providing a biophysical framework founded on theory and experiments, the method presented herein can be used by researchers without previous expertise in computer modeling or biophysical chemistry. The method will advance our understanding of enzyme catalysis on the molecular level by measuring the enthalpic and entropic changes associated with catalysis by enzyme variants with obstructed water tunnels. The protocol can be used for the study of membrane-bound enzymes and other complex systems. This will enhance our understanding of the importance of solvent reorganization in catalysis as well as provide new catalytic strategies in protein design and engineering.     

Acceleration of Germination of Super-Hard Rice Cultivar EM10 by Soaking with Red Onion

Red onion accelerated the germination of rice seeds and inhibited microbial infestation during germination. After germination with red onion for 16 h at 35 °C, super-hard rice EM10 showed a higher germination ratio (2.3 times), and it contained more GABA (2.3 times) and glucose (2.9 times) than that soaked without onion. Due to soaking with red onion, germinated EM10 was fortified with quercetin (18 mg/100 g).     

山茶属花粉外壁表面微形态特征的研究

在前人研究的基础上,利用光学显微镜和扫描电镜观察了山茶属17个组34个代表种（含变种）的花粉形态;按照韦仲新划分山茶属花粉类型的标准,对其进行归类,所有花粉分为3类：颗粒状至皱颗粒状纹饰、皱沟状纹饰和穴－网状纹饰;发现1种新的花粉类型：拟穴－网状纹饰。本文还对山茶属的某些分类学问题作了初步探讨。     

小果短柱茶花粉离体培养系统的研究

山茶的短柱茶组是优良种质资源,有必要对小果短柱茶(Camellia confusa Chang 1941)的花粉萌发和花粉管生长的生理特性进行研究.本文研究了花粉生活力、培养温度及pH对小果短柱茶花粉萌发和花粉管生长的影响.结果表明:最适离体萌发培养基为5%蔗糖、0.003%的硼酸,0.005%的氯化钙和12%的PEG...     

钙调素对花粉萌发和花粉管生长的效应

牛脑和玉米胚ＣａＭ能显著促进花粉萌发和花粉管生长（图１）,而ＣａＭ抑制剂ＴＦＰ、ＣＰＺ及另外两个专一性更强的抑制剂Ｃｏｍｐｏｕｎｄ４８／８０和Ｗ７均严重抑制甚至阻止花粉的萌发（图２,３）。用对ＣａＭ亲和性较低的Ｗ７同系物Ｗ５,在与Ｗ７同样浓度下,对花粉萌发和花粉管生长无明显影响。此外,Ｗ７对花粉萌发和花粉管生长的抑制效应可被外源ＣａＭ所消除（图４）。在花粉萌发过程中,其内源ＣａＭ含量显著上升,在花粉萌发率接近最大值时,花粉ＣａＭ含量达最高水平（图５）。上述结果表明ＣａＭ对花粉萌发和花粉管生长的调控起重要作用。     

Promotion of the Growth of Self-Incompatible Pollen Tubes in Lily by cAMP

Cyclic AMP, forskolin and 3-isobutyl-1-methylxanthine promotedthe elongation of self-incompatible pollen tubes in Lilium longiflorum.It appears that a functional cAMP-regulated system that involvesadenylate cyclase and phosphodiesterase is present in the lilystyle and is involved in the regulation of elongation of self-incompatiblepollen tubes. (Received January 21, 1993; Accepted June 19, 1993)     

A Contribution to the Pollen Morphology of Camellia (Theaceae)

The pollen morphology and ultrastructure of 20 species of Camellia (Theaceae) representing the four subgenera were examined. The pollen is tricolporate, spherical to slightly oblate or prolate, with scabrate to rugulate exine sculpturing. The tectum is traversed by perforations that vary in diameter. Pollen wall structure is tectate-columellate, the columellae fused to a footlayer. Endexine is present in all of the taxa examined. The greatest variation was observed in pollen size.     

Nitric Oxide Participates in Cold-Inhibited Camellia sinensis Pollen Germination and Tube Growth Partly via cGMP In Vitro

Nitric oxide (NO) plays essential roles in many biotic and abiotic stresses in plant development procedures, including pollen tube growth. Here, effects of NO on cold stress inhibited pollen germination and tube growth in Camellia sinensis were investigated in vitro. The NO production, NO synthase (NOS)-like activity, cGMP content and proline (Pro) accumulation upon treatment with NO scavenger cPTIO, NOS inhibitor L-NNA, NO donor DEA NONOate, guanylate cyclase (GC) inhibitor ODQ or phosphodiesterase (PDE) inhibitor Viagra at 25°C (control) or 4°C were analyzed. Exposure to 4°C for 2 h reduced pollen germination and tube growth along with increase of NOS-like activity, NO production and cGMP content in pollen tubes. DEA NONOate treatment inhibited pollen germination and tube growth in a dose-dependent manner under control and reinforced the inhibition under cold stress, during which NO production and cGMP content promoted in pollen tubes. L-NNA and cPTIO markedly reduced the generation of NO induced by cold or NO donor along with partly reverse of cold- or NO donor-inhibited pollen germination and tube growth. Furthermore, ODQ reduced the cGMP content under cold stress and NO donor treatment in pollen tubes. Meanwhile, ODQ disrupted the reinforcement of NO donor on the inhibition of pollen germination and tube growth under cold condition. Additionally, Pro accumulation of pollen tubes was reduced by ODQ compared with that receiving NO donor under cold or control condition. Effects of cPTIO and L-NNA in improving cold-treated pollen germination and pollen tube growth could be lowered by Viagra. Moreover, the inhibitory effects of cPTIO and L-NNA on Pro accumulation were partly reversed by Viagra. These data suggest that NO production from NOS-like enzyme reaction decreased the cold-responsive pollen germination, inhibited tube growth and reduced Pro accumulation, partly via cGMP signaling pathway in C. sinensis.     

Chemical Characterization of the Callose Plug Isolated from Camellia japonica Pollen Tube

A partially purified preparation of callose plug was obtainedfrom Camellia japonica pollen tube by limited enzymolysis anddensity centrifugation. The plug preparation consisted of proteinand polysaccharide at about 24% and 58% of dry weight, respectively.The plug polysaccharide was demonstrated to be a rß-1,3-glucanby staining reaction, acid hydrolysis, enzymatic digestion,infrared spectroscopy and methylation analysis. The averagedegree of polymerization of this glucan was calculated to beat least 90. This indicates that the plug callose has a longerchain than the tube wall callose. (Received June 15, 1983; Accepted November 26, 1983)     

山茶属连蕊茶组6种植物花粉形态特征研究

首次用扫描电子显微镜观察了山茶属(Camelliaa)连蕊茶组(Sect．Theopsis Coh．St．)6种植物花粉的形态特征。结果表明,这6种植物的花粉外壁纹饰可分为4大类型：皱波状(肖长尖连蕊茶Camellia subacutissima Chang和岳麓连蕊茶Chandelii Sealy);不规则皱网状(毛柄连蕊茶C.fraternal Hance和七瓣连蕊茶C.septempetala Changet L．L．Qi);脑纹状(柃叶连蕊茶C.euryoides Lindl．);穴状(小长尾连蕊茶C.parvicaudata Chang)。不同种植物花粉外壁纹饰存在一定差异,可为组内种间的区分提供参考依据,具有分类学意义。     

桃花粉离体萌发和花粉管生长特性研究

采用花粉离体萌发法研究不同培养基组分和培养条件对桃花粉萌发和花粉管生长的影响,同时对不同贮藏温度下的桃花粉寿命进行研究.结果表明:固体培养基与液体培养基对桃的花粉萌发率和花粉管长度影响差异不显著;10%蔗糖是大多数桃品种花粉的最适萌发条件;硼能提高桃花粉的萌发率,但对花粉管的生长没有促进作用;桃花粉在20℃～25℃的培养温度下萌发率最高,花粉管最长;桃花粉萌发率和花粉管长度在培养前3 h内上升最快,3～5 h上升趋势减弱,5 h后基本停止;随着贮藏温度的升高和贮藏时间的延长,花粉生活力呈降低的趋势.     

不同培养条件对黄连木花粉萌发和花粉管生长的影响

以黄连木花粉为试材,采用离体培养法研究了培养基组分和植物生长调节物质对黄连木花粉萌发和花粉管生长的影响.结果表明:花粉萌发和花粉管生长的适宜蔗糖浓度为15%,适宜培养温度为25℃;该培养条件下,花粉萌发率和花粉管长度分别达最大值63.3%和412.1 μm.硼酸、赤霉素(GA3)和吲哚乙酸(IAA)在一定浓度范围内,可以促进黄连木花粉萌发和花粉管生长,浓度过高时起抑制作用;最适宜黄连木花粉萌发和花粉管生长的硼酸浓度、赤霉素(GA3)和吲哚乙酸(IAA)浓度分别为100、50和15 mg/L.     

Effect of Growth Regulators and Light on Pollen Germination and Pollen Tube Growth in Pinus roxburghii Sarg

Pine (Pinus roxburghii) pollen grown in suspension cultureswas used to study the effects of growth regulators and lightconditions on germination and pollen tube growth. Indol-3-ylacetic acid, gibberellic acid, ethylene, abscisic acid and cyclicAMP (cAMP) at low concentrations (1–10 mg 1^–1) promotedgermination and tube growth. Addition of 1 and 10 mg 1^–1cAMP to any of the growth regulators had a promotory effect.Pollen tube growth decreased in white light as compared to thedark, and was increased in red light. Far-red light counteractedthe effect of red light. The effect of growth regulators incausing the enhanced tube growth appears to be manifested throughsubstances such as cAMP, and phytochrome seems to be involved. Pinus roxburghii, pine, pollen germination, pollen tube growth, growth regulators, cyclic AMP, phytochrome     

水在有机介质酶催化反应中的作用

本文针对有机介质酶催化反应中水的作用,结合最新研究进展作了综合评述。指出水在有机介质中对维持酶的活力构象起到“润滑剂”作用,水活度是衡量水作用的有效参数。分析了酶的水化程度、水化方式、有机溶剂及固定化载体对酶活力的影响及其作用机理,并对反应过程中水的控制问题进行了讨论。