12种金花茶组植物产花量和产叶量研究

对12种保存在南宁市金花茶公园基因库内的金花茶组植物进行产花量和产叶量研究,目的是筛选出适合花用、叶用的优良金花茶组植物。根据对12种金花茶组植物的产花量和产叶量进行比较的结果,筛选出产花量较高的花用金花茶有:中东金花茶、防城金花茶、龙州金花茶;筛选出产叶量较高的叶用金花茶有:龙州金花茶、东兴金花茶、防城金花茶、毛籽金花茶、毛瓣金花茶。     

河南省不同产地3种菊头蝠RAPD分析

用随机引物对河南省角菊头蝠（Rhinolophus cornutus）、不同产地的中菊头蝠（Rhinolophus affinis）和马铁菊头蝠（Rhinolophus ferrumequinum）进行DNA多态性研究,以探讨它们之间的亲缘关系。从20个随机引物中优化出15个引物对基因组DNA进行扩增,10个标本共扩增出184条DNA谱带,平均每个引物扩增出12条谱带,其中多态性谱带173条,多态率为94%。聚类结果表明：对同种蝙蝠,同一地理区域的个体之间分化较小,不同地理区域的个体之间分化较大;中菊头蝠与角菊头蝠之间的亲缘关系较近,而与马铁菊头蝠之间的亲缘关系较远。     

12种金花茶组植物在南宁市的物候期观测

为了了解金花茶在南宁市栽培的物候期,连续3年对南宁市金花茶公园引种的12种金花茶组植物进行物候期调查。结果表明:12种金花茶展叶期大部分集中在春季和冬季。花期除了东兴金花茶、龙州金花茶、毛籽金花茶以外主要集中在12月至翌年2月。果熟期除了东兴金花茶和龙州金花茶以外主要集中在12月至翌年10月。不同物种的展叶期,花期和果期持续时间差异不大。气温也影响着金花茶的物候期。     

金福菇菌株的酯酶同工酶分析

本文采用酯酶同工酶分析和聚类分析技术,对15个金福菇菌株的遗传多样性和亲缘关系进行分析鉴定,以便为金福菇的遗传育种提供依据。试验结果表明：共检测到18条谱带,其中有2条谱带的分布频率为100%,是所有菌株的特征谱带;15个菌株共有14种酶带类型,不同菌株的酶带数在8条至12条之间。聚类分析结果表明,15个菌株间的遗传相似系数在0.33~1.00之间,在相似系数为0.62时,可将15个金福菇菌株划为3大类群。老挝金福菇TgLo菌株与国内金福菇的亲缘关系最远;同一菌株的不同分离株如Tg1.1与Tg1.2、Tg10.1、Tg10.2与Tg10.3间的遗传相似系数在0.94以上;菌株Tg3与Tg8,Tg12与Tg10.2或Tg10.3间的遗传相似系数也达到0.94,可认为是同物异名。上述结果表明,酯酶同工酶方法可有效应用于金福菇的菌株鉴定及亲缘关系分析。     

两种金花茶染色体形态的初步研究

本文报导了金花茶Camellia chrysantha与显脉金花茶C.cuphlcbia的染色体数目与形态。两种金花茶体细胞染色体数目都是Zn=30。但核型之间有明显差异,而小金花茶C.microcarpa与金花茶的核型则较相近。     

小果金花茶的染色体组型研究及应用上的探讨

用小果金花茶(Camellia chrysantha(Hu)Tuyama var.micro-carpa Mo et Huang)根尖分生组织细胞的染色体进行组型研究,确认其体细胞染色体数目2n=30。用臂比、相对长度来识别同源染色体对。测量结果表明,小果金花茶有10对中部着丝点染色体 (m—型),4对近中部着丝点染色体(sm—型),1对近端部着丝点染色体(st—型),在第14对染色体上有一对大随体。此组型与国内外发表的红山茶组某些种的组型相似,唯有随体与次缢痕等情况不同。表明金花茶组与红山茶组之间的杂交是可能获得成功的。金花茶的育种方向应以集红山茶组的其他优点及金花茶的花色为目标,把组间杂交与细胞学研究相结合,以加速金花茶的育种进程。     

高寒山区野生金花茶种植繁育技术探讨

高寒山区野生金花茶原产自我国,其栽培历史悠久,具有广泛的用途。高寒山区野生金花茶主根发达,须根量较少,因此对栽培技术有着严格要求,而且移植成活率较低,给农户造成一定的经济损失。目前,我国对高寒山区野生金花茶的理论研究与实践研究还不够成熟,仍处于发展的初级阶段。基于此,通过在广西天峨县向阳镇林细村罗家坳野生金花茶种植示范基地种植实践,总结了高寒山区野生金花茶的栽培技术要点,提高高寒山区野生金花茶成活率,为广大野生金花茶种植户提供一些经验借鉴。     

应用RAPD技术研究4种鲍的亲缘关系

应用RAPD技术研究 4种鲍的亲缘关系结果表明 ,4种鲍群体中 2 0个有效引物共扩增出 5 38条DNA带 ,平均每个引物扩增的条带数为 2 6 .9;扩增的多态性条带数 136 ,平均每个引物扩增的多态性条带数为 6 .8;多态位点百分数为 2 5 .3%。盘鲍群体和皱纹盘鲍群体之间遗传距离与遗传一致度分别为 0 .2 8和 0 .72 ,杂色鲍群体和九孔鲍群体之间遗传距离与遗传一致度分别为 0 .32和 0 .6 8。聚类分析把盘鲍群体和皱纹盘鲍群体聚为 1组 ,二者亲缘关系较近 ;杂色鲍群体和九孔鲍群体聚为 1组 ,二者亲缘关系也较近     

我国金花茶研究概述

本文简述了我国在金花茶杂交育种、染色体数目及核型分析、金花茶的分类及其演化、金花茶孢粉学及应用研究等方面的最新进展及存在的问题,为今后金花茶的研究提供参考。     

利用SSR和RAPD标记分析中国部分地区晚疫病菌群体遗传多样性

利用SSR和RAPD对来自福建、黑龙江、河北和内蒙古4个地理群体的80个马铃薯晚疫病菌（phytophthora infestans）株进行了遗传多样性分析。13对SSR引物共扩增出76条谱带,多态性条带比率78.9%,相似系数变化范围0.00～0.42之间;筛选出的14条RAPD引物共扩增出189条谱带,多态性条带比率95.2%,相似系数变化范围0.04～0.66之间。遗传多样性分析表明,在4个群体中,福建群体的多样性更为丰富。遗传相似性分析显示,黑龙江和内蒙古两个群体间的遗传相似性最高,而福建和河北两个群体间的遗传相似性最低。聚类分析显示,来自南方福建的菌株与来自北方黑龙江、河北和内蒙古的菌株亲缘关系较远,且福建群体分布于更多的聚类组,显示出更高的遗传变异度。     

Starch concentration and impact on specific leaf weight and element concentrations in potato leaves under varied carbon dioxide and temperature

Foliar concentrations of starch and major elements, nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg), along with specific leaf weight (SLW) were determined in the potato (Solanum tuberosum L.) cvs 'Denali', 'Norland', and 'Russet Burbank' grown for 35 days under CO2 concentrations of 500, 1,000, 1,500 and 2,000 micromoles mol-1 at both 16 degrees C and 20 degrees C air temperature. The starch concentration, pooled from the three cultivars, increased with increasing CO2 concentration at both 16 degrees C and 20 degrees C and was consistently higher at 16 degrees C than at 20 degrees C. The SLW (g m-2) was positively related to the foliar starch concentration on the basis of leaf area or dry weight. The concentrations of N, P, Ca, and Mg in leaves were negatively related to starch concentration under approximately 14% starch on a dry weight basis. Above 14% starch, there was no significant relationship between element and starch concentrations. Similar patterns were seen when the SLW and element concentrations were expressed on a starch-free basis. In contrast, the leaf concentration of K was not closely related to the starch concentration because the K concentration was similar at varied CO2 levels. The results of this study indicate that the changes in SLW and concentrations of N, P, Ca, and Mg in potato leaves only partially resulted from the changed starch concentration.     

Arbuscular mycorrhizal fungi contribute to C and N enrichment of soil organic matter in forest soils

Increasing evidence suggests that accretion of microbial turnover products is an important driver for isotopic carbon (C) and nitrogen (N) enrichment of soil organic matter (SOM). However, the exact contribution of arbuscular mycorrhizal fungi (AMF) to soil isotopic patterns remains unknown. In this study, we compared ¹³C and ¹⁵N patterns of glomalin-related soil protein (GRSP), which includes a main fraction derived from AMF, litter, and bulk soil in four temperate rainforests. GRSP was an abundant C and N pool in these forest soils, showing significant ¹³C and ¹⁵N enrichment relative to litter and bulk soil. Hence, cumulative accumulation of recalcitrant AMF turnover products in the soil profile likely contributes to ¹³C and ¹⁵N enrichment in forest soils. Further research on the relationship between GRSP and AMF should clarify the exact extent of this process.     

Starch concentration and impact on specific leaf weight and element concentrations in potato leaves under varied carbon dioxide and temperature

Foliar concentrations of starch and major elements, nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg), along with specific leaf weight (SLW) were determined in the potato (Solanum tuberosum L.) cvs ‘Denali’, ‘Norland’, and ‘Russet Burbank’ grown for 35 days under CO₂ concentrations of 500, 1,000, 1,500 and 2,000 μmol.mol^‐1 at both 16°C and 20°C air temperature. The starch concentration, pooled from the three cultivars, increased with increasing CO₂ concentration at both 16°C and 20°C and was consistently higher at 16°C than at 20°C. The SLW (g.m^‐2) was positively related to the foliar starch concentration on the basis of leaf area or dry weight. The concentrations of N, P, Ca, and Mg in leaves were negatively related to starch concentration under =14% starch on a dry weight basis. Above 14% starch, there was no significant relationship between element and starch concentrations. Similar patterns were seen when the SLW and element concentrations were expressed on a starch‐free basis. In contrast, the leaf concentration of K was not closely related to the starch concentration because the K concentration was similar at varied CO₂ levels. The results of this study indicate that the changes in SLW and concentrations of N, P, Ca, and Mg in potato leaves only partially resulted from the changed starch concentration.     

Effect of introduced exotic tree litter on consumption patterns of the introduced exotic isopod Armadillidium vulgare

The feeding preferences and consumption rates of the exotic woodlouse Armadillidium vulgare were measured on litters from the autochthonous Rio Grande cottonwood and the exotic Russian olive. When offered a choice between five litter types (green and shed leaves of Russian olive and cottonwood, and fruits of Russian olive), the isopods consumed more of the exotic plant litter (green leaves and the fruits of Russian olive) than of the autochthonous cottonwood. When offered only one diet, consumption rates of green leaves and fruits of Russian olive were again the highest. Feeding was related with N and C:N ratios of the litter, with highest consumption of diets with low and high C:N ratios and lowest consumption of diets with intermediate C:N ratios. The N content was highest (and C:N ratios lowest) on isopods feeding shed leaves of Russian olive. Growth was not related to the amount or the C:N ratio of the food consumed, being highest for animals feeding on shed leaves of cottonwood. Our results show that the consumption patterns and the C and N body composition of the exotic woodlouse A. vulgare are altered when fed with Russian olive litter, suggesting that the replacement of the autochthonous cottonwood by the exotic Russian olive may negatively affect the maintenance of the population of these exotic detritivores in the area.     

The potential response of global terrestrial carbon storage to a climate change

An analysis is undertaken to examine the potential impacts of a global climate change on patterns of potential terrestrial C storage and resulting fluxes between terrestrial and atmospheric pools. A bioclimatic model relating the current distribution of vegetation to global climate patterns is used to examine the potential impacts of a global climate change on the global distribution of vegetation. Climate change scenarios are based on the predictions of two general circulation model equilibrium simulations for a 2XCO₂ atmosphere. Current estimates of C reserves in the vegetation types and associated soils are then used to calculate changes in potential terrestrial C storage under the two climate change scenarios. Results suggest a potential negative feedback to increasing atmospheric concentrations of CO₂, with the potential for terrestrial C storage increasing under both scenarios. These results represent an equilibrium analysis, assuming the vegetation and soils have tracked the spatial changes in climate patterns. An approach for providing an estimate of the transient response between the two equilibria (i.e., current and 2XCO₂ climates) is presented. The spatial transitions in vegetation predicted by the equilibrium analyses are classified as to the processes controlling the transition (eg., succession, dieback, species immigration). Estimates of the transfer rates related to these processes are then used to estimate the temporal dynamics of the vegetation/soils change and the associated C pools. Results suggest that although the equilibrium analyses show an increased potential for C storage under the climate change, in the transient case the terrestrial surface acts as a source of CO₂ over the first 50 to 100 yrs following climate change.     

植物C_2H_2型锌指蛋白的研究进展

锌指蛋白是转录因子的一种,对真核生物的生长发育及逆境胁迫的耐受能力都有着重要关系,而植物C2H2型锌指蛋白是研究较多、较为明确的一种锌指蛋白,该蛋白大部分锌指结构具有一段高度保守的氨基酸序列QALGGH,这是植物中独有的特征,且据报道该C2H2型锌指蛋白与逆境胁迫是相关的。本文主要综述了植物C2H2型锌指蛋白的分类、结构和功能,植物C2H2型锌指蛋白与DNA、RNA和蛋白质的相互作用,以及概述了与盐胁迫、低温胁迫、干旱胁迫、氧胁迫和光胁迫等逆境胁迫相关的植物C2H2型锌指蛋白,最后还对其进一步的深入研究进行了展望,这就为日后利用基因工程技术改良作物品质、提高作物的抗逆性提供了有利条件。     

Microbial community composition shapes enzyme patterns in topsoil and subsoil horizons along a latitudinal transect in Western Siberia

Soil horizons below 30 cm depth contain about 60% of the organic carbon stored in soils. Although insight into the physical and chemical stabilization of soil organic matter (SOM) and into microbial community composition in these horizons is being gained, information on microbial functions of subsoil microbial communities and on associated microbially-mediated processes remains sparse. To identify possible controls on enzyme patterns, we correlated enzyme patterns with biotic and abiotic soil parameters, as well as with microbial community composition, estimated using phospholipid fatty acid profiles. Enzyme patterns (i.e. distance-matrixes calculated from these enzyme activities) were calculated from the activities of six extracellular enzymes (cellobiohydrolase, leucine-amino-peptidase, N-acetylglucosaminidase, chitotriosidase, phosphatase and phenoloxidase), which had been measured in soil samples from organic topsoil horizons, mineral topsoil horizons, and mineral subsoil horizons from seven ecosystems along a 1500 km latitudinal transect in Western Siberia. We found that hydrolytic enzyme activities decreased rapidly with depth, whereas oxidative enzyme activities in mineral horizons were as high as, or higher than in organic topsoil horizons. Enzyme patterns varied more strongly between ecosystems in mineral subsoil horizons than in organic topsoils. The enzyme patterns in topsoil horizons were correlated with SOM content (i.e., C and N content) and microbial community composition. In contrast, the enzyme patterns in mineral subsoil horizons were related to water content, soil pH and microbial community composition. The lack of correlation between enzyme patterns and SOM quantity in the mineral subsoils suggests that SOM chemistry, spatial separation or physical stabilization of SOM rather than SOM content might determine substrate availability for enzymatic breakdown. The correlation of microbial community composition and enzyme patterns in all horizons, suggests that microbial community composition shapes enzyme patterns and might act as a modifier for the usual dependency of decomposition rates on SOM content or C/N ratios.     

A note on the variation of phaseolin among common bean landraces collected in Eastern Asia

Summary Phaseolin seed protein was used as a marker to reveal the origin, Mesoamerican or Andean, of common bean (Phaseolus vulgaris) accessions cultivated in some countries (Korea, China, and Japan) of eastern Asia. Andean cultivars (T and C phaseolin patterns) are predominant in this geographical area. Introductions from Middle America, represented by cultivars with S phaseolin type, also occurred at lower rate. In all cases, genotypes with larger seeds have been favoured.     

Seed protein electrophoretic characterization of cowpea (Vigna unguiculata) germplasm from IITA gene bank

Summary The total seed protein, globulin and albumin fractions of 20 cowpea (V. unguiculata) accessions from IITA gene bank were investigated by SDS-polyacrylamide gel electrophoresis. Total seed protein extracts were prepared from the defatted meal by homogenisation and centrifugation in Tris-glycine buffer. The globulins and albumins were obtained from the total protein extract by exhaustive dialysis against sodium acetate buffer. Two main total seed protein electrophoretic patterns were observed with respect to the 39 and 20 kD subunits, which were present in six out of the twenty accessions analysed. While there was no correlation between seed colour and total seed protein banding pattern, the six insect-resistant cultivars were characterized by the presence of the 39 and 20 kD subunits. The globulins were the predominant class of the total seed proteins and consisted mainly of 64, 58, 56 and 14 kD subunits which make up CP1 and CP2, the major globulins. The albumins in all accessions were a heterogeneous protein fraction consisting of both high and low molecular weight subunits. It was suggested that the insect-resistant cultivars may be genetically related and that the 39 and 20 kD subunits may be involved in the insect resistance mechanism.     

Potential net soil N mineralization and decomposition of glycine-C in forest soils along an elevation gradient

The objective of this research was to better understand patterns of soil nitrogen (N) availability and soil organic matter (SOM) decomposition in forest soils across an elevation gradient (235-1670 m) in the southern Appalachian Mountains. Laboratory studies were used to determine the potential rate of net soil N mineralization and in situ studies of ¹³C-labelled glycine were used to infer differences in decomposition rates. Nitrogen stocks, surface soil (0-5 cm) N concentrations, and the pool of potentially mineralizable surface soil N tended to increase from low to high elevations. Rates of potential net soil N mineralization were not significantly correlated with elevation. Increasing soil N availability with elevation is primarily due to greater soil N stocks and lower substrate C-to-N ratios, rather than differences in potential net soil N mineralization rates. The loss rate of ¹³C from labelled soils (0-20 cm) was inversely related to study site elevation (r=−0.85; P<0.05) and directly related to mean annual temperature (+0.86; P<0.05). The results indicated different patterns of potential net soil N mineralization and ¹³C loss along the elevation gradient. The different patterns can be explained within a framework of climate, substrate chemistry, and coupled soil C and N stocks. Although less SOM decomposition is indicated at cool, high-elevation sites, low substrate C-to-N ratios in these N-rich systems result in more N release (N mineralization) for each unit of C converted to CO₂ by soil microorganisms.