Intra-plant variation in cyanogenesis and the continuum of foliar plant defense traits in the rainforest tree Ryparosa kurrangii (Achariaceae)

At the intra-plant level, temporal and spatial variations in plant defense traits can be influenced by resource requirements, defensive priorities and storage opportunities. Across a leaf age gradient, cyanogenic glycoside concentrations in the rainforest understory tree Ryparosa kurrangii B.L. Webber were higher in young expanding leaves than in mature leaves (2.58 and 1.38 mg g(-1), respectively). Moreover, cyanogens, as an effective chemical defense against generalist herbivores, contributed to a defense continuum protecting foliar tissue during leaf development. Chemical (cyanogens and phenolic compounds) and phenological (delayed greening) defense traits protected young leaves, whereas mature leaves were largely protected by physical defense mechanisms (lamina toughness; explained primarily by leaf mass per area). Cyanogen concentration was considerably higher in floral tissue than in foliar tissue and decreased in floral tissue during development. Across contrasting tropical seasons, foliar cyanogenic concentration varied significantly, being highest in the late wet season and lowest during the pre-wet season, the latter coinciding with fruiting and leaf flushing. Cyanogens in R. kurrangii appear to be differentially allocated in a way that maximizes plant fitness but may also act as a store of reduced nitrogen that is remobilized during flowering and leaf flushing.     

杉木优良家系苗期性状的遗传变异研究

对杉木１２０ 个优良家系子代苗期１５ 个主要性状（ 包括苗高、分枝数、根系发育、生物量等） 进行了遗传变异研究，并对各性状进行了单株遗传力估算。结果表明，侧根长、冻害率、地下鲜重、侧根数、地下干重等性状在家系间差异极显著，并有较高的单株遗传力（ 均达０－４ 以上） 。     

杉木第二代种子园亲本性状遗传变异研究

以沙县官庄国有林场22年生的杉木第2代种子园为研究对象,对220个无性系进行系统测定,探讨了无性系生长、形质和结实性状的遗传变异规律,结果表明:生长性状、形质性状和结实性状在无性系间的差异达到极显著水平,而且无性系的重复力值均较大;从220个无性系中综合筛选出丁74等35个优良无性系,各优良无性系生长量大、结实性状良好,22年生时的平均树高、胸径、材积值分别高达17.56 m、33.60 cm和0.803 35 m3,分别大于种子园中调查的220个无性系平均值的20.36%、17.73%和57.32%,综合性状表现优良,可用作高世代种子园建园材料和杂交育种的亲本材料。     

The effects of thinning and burning treatments on within-canopy variation of leaf traits in hardwood forests of southern Ohio

Leaf nitrogen content (N_mass, %) and leaf mass per area (LMA, g m⁻²) are two important features that are closely linked to the photosynthetic performance of plants and, thus, the NPP of forest ecosystems. Forest management practices, such as burning and thinning, change stand structure and soil dynamics, which may result in changes in N_mass and LMA. The objective of this study was to understand how N_mass and LMA of seven canopy tree species/genus (Quercus alba, Q. coccinea, Q. prinus, Q. velutina, Carya spp., Acer rubrum, and Liriodendron tulipifera) responded to (i) thinning and/or burning treatments and to (ii) different landscape and soil properties in southern Ohio. We collected leaves from the top, and bottom, of five individuals of each taxa in each treatment unit. Leave traits (N_mass and LMA) were compared using analysis of variance followed by orthogonal contrasts. To further understand the factors that influence the canopy leaf traits, we used regression tree analysis (RTA) to examine how variations of LMA and N_mass were linked to thinning and/or burning treatments, soil, and landscape variables. Finally, we assessed the potential ramifications of changes in these traits on canopy carbon budgets using a PnET-Day model, which is a daily time-step canopy carbon exchange model. We found significant effects of thinning, burning, and their interactions on LMA at the bottom of the crown while none of the treatments showed significant effects on LMA at the top of the crown. N_mass responded significantly to only burning treatment. RTA results exhibited minor effects of landscape features and soil properties on N_mass and LMA. Interspecific differences accounted for most variations of both leaf traits. Sensitivity analysis of PnET-Day model suggested these subcanopy changes in LMA increased the annual net primary production (NPP) by 8%. In summary, our results suggest that forest management can substantially influence canopy leaf traits such as N_mass and LMA and that alteration of these traits can influence forest NPP. Given the role of forests as global carbon sinks, the potential influence of thinning and burning on canopy traits, and thus NPP, is an important consideration for forest management.     

衡阳市油茶优良单株抗病性研究

经过连续2a对油茶炭疽病重感病区的优株的自然抗病性研究及多项因子的试验测定，结果表明：油茶果实的抗病性(抗炭疽病)与其果实皮层厚度无关；与果实表皮层厚度呈负相关；与表皮层的细胞结构排列的紧密程度也有关，细胞结构排列越整齐、紧密，抗病性能越强，反之，抗病性能差。以及2001年对确选的优株无性系植株的考察、印证，最后筛选出了抗病的优良单株17株。为解决油茶炭疽病防治提供了可行的新途径。     

Plant functional types rather than climate or soil determine leaf traits in the forest biomes of eastern China

Nitrogen (N) has great ecological importance, but the biogeographic pattern across forest biomes in China has only recently been explored. Here we conducted a systematic census of leaf C and N following the same protocol to explore the variations of leaf traits, and their possible responses to plant functional types (PFTs) and environmental factors. Results showed that leaf traits varied substantially across biomes, and the relationships of PFTs to climatic factors were stronger than those of PFTs versus soil nutrient proxies, indicating that plant species composition might be a better predictor of plant species distribution with climate than leaf traits. Soil nutrient proxies explained more variation of leaf traits than climate, which demonstrates that leaf traits reflect important aspects of plant responses to soil nutrients. Importantly, partial general linear models analyses found that PFTs showed the greatest direct influence for leaf traits, and climate and soil affected leaf traits mainly through the change in plant species composition rather than having direct impacts. Hence, we concluded that leaf traits were largely controlled by PFTs rather than climate or soil at the biome scale. The results favored the species composition hypothesis, indicating that leaf nutrient concentration is mainly determined by PFTs.     

Genetic variation in architectural seedling traits of Patagonian cypress natural populations from the extremes of a precipitation range

? Species distributed along wide environmental ranges are expected to be either plastic or adapted to local optima. The elucidation of which of these alternatives prevails, is crucial in planning breeding and conservation strategies for not yet domesticated species. Austrocedrus chilensis (Cupressaceae) is the most commercially important conifer of the temperate forests of Argentina and the target of a domestication program. A steep precipitation gradient characterizes its Argentinean range.

? Variation within and differentiation among four natural populations of this Patagonian cypress representative of two contrasting precipitation regimes (>1 300 and 330 mm per y) were assessed by analyzing several morpho/architectural traits in one-year-old seedlings grown in a greenhouse.

? Progenies from one of the two xeric populations did not differ from those corresponding to both humid-site populations. The two most variable populations in terms of additive genetic variance belonged to contrasting precipitation regimes. Differentiation among populations was low as measured by each and every variable (average Q _st = 0.088). Morphological traits related to the main axis size would have a dubious adaptive meaning.

? The results suggest that the Patagonian cypress would have not evolved genetic pools adapted to local optima, and thus it appears to be a phenotypically plastic species, at least regarding growth at juvenile age.

     

现代家庭厨柜材料及特点

现代家庭厨房厨柜的地位尤为重要。橱柜基材的材料有刨花板、防水刨花板、中密度纤维板和细木工等。覆面材料有防火板、PVC贴面材料和三聚氰胺装饰板。台面材料有防火板贴面台面和人造理石台面。厨柜材料今后发展的趋势是：基材以防水刨花板及中密度纤维板为主，面材是以多种图案的防火板为主，台面材料是向着人造理石台面的方向发展。     

龙泉杉木三代种子园子代林主要生长性状变异研究

对营造在浙江省龙泉市林科院6年生杉木三代种子园家系(36个家系,1个对照)子代林的树高、胸径和材积进行测定与分析.结果表明:6年生杉木的树高、胸径和材积3个生长性状在家系间差异达极显著,且有相对较高的广义遗传力,而材积有中等以上的遗传变异系数.杉木三代种子园有较好的群体改良效果,6年生时材积的遗传增益比对照提高了14.89％.以材积为依据,采用对比法选择出9个早期速生型杉木优良家系,其群体的树高、胸径和材积平均值分别大于对照10.04％、15.99％和45.69％.     

Genotypic effects on the variation of wood quality and growth traits in plantation forest made by cutting cultivars of Japanese cedar

We studied the effect of genotypes of planting stocks regarding the variation of the modulus of elasticity of tree trunks on standing trees (trunk-MOE), tree height (TH), and diameter at breast height (DBH) in a 19-year-old Japanese cedar plantation made with root cuttings. Trunk-MOE was assessed nondestructively using a tree-bending method. Genotypes of individual trees were detected using the random amplified polymorphic DNA (RAPD) technique. RAPD analysis revealed that the sampled plantation consisted of 14 genotypes. Genotypic effects on DBH and TH were unclear, and there was no significant difference among genotypes. This result indicated that an acquired variation should have more influence than an inherited variation on DBH and TH. For trunk-MOE, there were significant differences among the four largest genotypes at the 5% level. However the coefficient of variation in trunk-MOE of each genotype ranged from 7.5% to 26.8%. It seems reasonable to assume that the wide variation in trunk-MOE in a sampled plantation may depend on the environmental effect within a clone as well as on the genetic origin of clones. We therefore conclude that the use of multiple planting stocks from different cuttings for which the wood quality is unknown contributed strongly to the wide variation in trunk-MOE in the plantation of Japanese cedar.     

Examination of the consistency of plant traits driving oil yield and quality in short-rotation coppice cultivation of Eucalyptus polybractea

The value of eucalyptus oil for medicinal purposes is based largely on its cineole content. The prime commercial species for cineole production in Australia is Eucalyptus polybractea (blue mallee). Despite the long history of blue mallee harvesting in Australia, there has been little research on the establishment of plantations of the species or on the efficacy of short-rotation coppice cultivation with respect to the consistency of oil yield and quality from rotation to rotation. This study aims to assess if subsequent coppice oil traits reflect sapling traits and if the coppice oil traits under short-rotation cultivation are consistent from one rotation to the next. A trial plantation was established in a key eucalyptus oil harvesting district in Victoria. Firstly, the oil-related traits of 20 saplings harvested 3.5 years after planting were compared with those of their subsequent coppice harvested after 12 months regrowth. Despite the expected differences in total biomass, the oil-related traits of blue mallee saplings were mostly well reflected in their subsequent coppice. Total above ground biomass and foliar oil concentration were significantly related between saplings and coppice, and cineole proportion showed a Pearson's correlation of 0.93 between harvests. Nevertheless, the mean foliar oil concentration in the coppice was 148 mg g⁻¹ dw compared with 107 in the saplings, and the coppice foliage, on average, showed significantly reduced cineole with a mean of 87% in the saplings (maximum of 95.6%) compared to a mean of only 80% in the coppice (maximum of 87.0%). Secondly, the oil traits of 20 coppice plants from one 12-month harvest rotation to the next were compared. Again, total above ground biomass, foliar oil concentration and cineole proportion were significantly related between the harvests, with cineole proportion having a Pearson's correlation of 0.90 between rotations. The coppice between rotations were remarkably consistent in terms of biomass and oil traits and indeed mean coppice cineole yields were 28.6 and 29.7 g in rotations 1 and 2, respectively. The results support the screening of key oil-related traits in saplings for the selection of elite genotypes for plantations, and the use of short-rotation cultivation of the plantations for continued oil harvesting. Furthermore, no relationship was observed between biomass and oil concentration in the blue mallee saplings or coppice, suggesting selection gains in a given key oil trait will not result in losses in another.     

道路绿化中的植物配置

道路绿化是道路环境的一个很重要的要素之一，因而也越来越受到人们的重视。结合多年来从事园林景观设计的经验，从植物配置方面对道路绿化进行探究。     

Influence of nonhost plant diversity and natural enemies on the potato leafhopper, Empoasca fabae, and pea aphid, Acyrthosiphon pisum, in alfalfa

We examined the effects of nonhost plant diversity and predators on the potato leafhopper, Empoasca fabae (Harris), the pea aphid, Acyrthosiphon pisum (Harris), and their primary host plant, alfalfa, Medicago sativa L. Potato leafhopper intensity (i.e., leafhoppers/alfalfa stem density) and plant damage (i.e., hopperburn) were significantly greater in alfalfa mono- than in polycultures of alfalfa mixed with nonhost plant species. There was no significant effect of nonhost plant diversity on pea aphid intensity or on predator abundance. Predator:prey ratios were higher in poly- than in monoculture. One predator, Nabis sp., was selected for further study. A microcosm experiment indicated that Nabis is an effective predator of both herbivores, and suggested that nonhost plant diversity may enhance the predation of leafhoppers by Nabis. These results suggest that nonhost plant diversity and Nabis limit leafhopper populations and protect alfalfa from herbivory. The potential for nonhost plants to increase herbivore movement and vulnerability to predation is discussed.     

北方园林中冬季植物景观的表现

冬季在我国北方是一年四季中最长的季节 ,园林中冬季植物景观的表现是设计中的难点 ,为了表现好冬季园林中的植物景观 ,应做到常绿针叶树与落叶树并重 ,适当点缀常绿阔叶树 ,同时应加强冬态管理。     

园林植物反季节栽植关键技术的探讨

在城市绿化中，如何保持较高的反季节栽植成活率是绿化施工的重点和难点。总结了城市绿化实施反季节栽培的关键措施，从植物材料的选择、起苗技术、栽植技术、栽后养护等技术环节进行了详细阐述，特别是加强栽后当年的管理，对北方地区城市绿化反季节栽植工作具有～定的指导意义。     

高效毛细管电泳在分离植物蛋白质中的应用

蛋白质的分离技术在蛋白质研究中起到了举足轻重的作用。毛细管电泳作为一项较新的分离技术,以其高通量、高灵敏度、快捷低耗的优势弥补了传统双向凝胶电泳的不足。本文分别从毛细管电泳技术的不同分离方式出发,对其在植物蛋白质分离中的研究进展进行了综述,重点分析了毛细管区带电泳和涂层毛细管电泳对植物蛋白质进行分离的优缺点。     

浅谈棕榈科植物在房地产园林中的应用

棕榈科植物是华南地区重要的园林植物资源，全科约210属2800余种，以其独特的风格、别致的形态特征，成为营造园林绿化景观的热门树种。最早流行于欧美园艺界，后被世界各地争相采用为行道树、庭荫树，园景树。当前特别在广州的房地产园林中应用广泛。本文根据棕榈植物的特点和造景功能，对在广州市楼盘园林里恰当运用棕榈科植物，形成地方特色作一探讨。     

湖南乡土树种在园林绿化中的应用

通过对乡土树种应用优势的分析，阐述了湖南乡土树种在园林中的应用价值。同时提出在应用中如何创造园林景现。     

防城金花茶国家级自然保护区次生季雨林木本植物多样性与种间联结性

在防城金花茶国家级自然保护区建立1 hm2次生季雨林动态监测样地,以样地内胸径≥1 cm的木本植物为研究对象,探讨木本植物组成、群落结构、物种α多样性,并定量分析样地内最重要的15个优势种的种间联结性.结果表明:样地内的木本植物个体数量为9557株,分属于63科、128属、188种,优势科为茜草科、樟科和桑科,具有明显...