野生浆果悬钩子营养成份分析

悬钩子(Rubus)广泛生长在山坡、沟旁和荒野间。果似草莓。体积约1.5厘米直径大小。味酸甜。成熟期在六月下旬至七月中旬之间。在我国分布的有几十种之多。为了开发和利用野生资源,我们在秦巴山区采集了4个不同种的悬钩子样品,对其营养成分进行了较系统的分析测定。     

中国东南部部分悬钩子果实的营养成分

对中国东培１２种悬钩子果实营养成分的分析结果表明,悬钩子果实氨基酸含量为５．４４３－８．４１１ｇ／１００ｇ．ＤＷ,,ＶＥ为０．９１８－２．１１９ｍｇ．１００ｇ．ＦＷ,有机酸为０．７２１－４．９１０％和丰富矿质元素,有较高的营养价值和医疗保健作用。营养成分的含量在种间和种内存在差异。     

云南9种悬钩子属植物果实品质比较与综合评价

目的：对云南9种野生悬钩子果实品质进行初步测定与分析，筛选出果实品质较好的悬钩子种质。方法：以云南省9种野生悬钩子属植物果实为材料，测定果实的横径、纵径、果形、果色和8种营养成分等指标，并运用多重比较、主成分分析和隶属函数等方法，对野生悬钩子果实品质进行综合评价。结果：不同悬钩子果实表型和营养成分存在显著差异；主成分分析将果实表型和营养成分指标简化为四个主成分，可解释所有变量原始信息的85.643%；采用隶属函数法确定权重，结合主成分分析，构建了悬钩子果实品质综合评分模型，并对9种悬钩子果实品质进行综合评价，得分排序为：光滑悬钩子>红泡刺藤>桔红悬钩子>大乌泡>高粱泡>插田泡>掌叶悬钩子>栽秧泡>红毛悬钩子。研究筛选出两份果实品质相对较好的种质资源，分别为光滑悬钩子和红泡刺藤。结论：光滑悬钩子的果实纵、横径和果重最大，蛋白质、氨基酸和有机酸含量较低，总黄酮含量最高；红泡刺藤果实横径和果重较大，总糖、花色苷、总酚含量极显著高于其他所有悬钩子，总黄酮含量较高且有机酸含量较低。在今后的驯化栽培时，可优先选择光滑悬钩子和红泡刺藤。     

裂叶悬钩子器官发生的细胞组织学观察

裂叶悬钩子(Rubus laciniatus W.cv.Thornless Evergreen)是蔷薇科悬钩子属一种重要的小果类植物。我们在以离体叶片诱导不定芽成功的基础上,对其叶片不定芽形态发生过程作了进一步观察。供接种的叶片从基部去掉叶柄,按前文的操作顺序进行灭菌,接种和培养。从培养第3天起,从叶片基部与叶柄接合处切取材料固定,以后每隔2天取样一次,一直取到20     

悬钩子属种质的评价

在进行了７省悬钩子资源调查的基础上,在南京建立了悬钩子属田间基因库。３年来对田间基因库内保存并开花结果的３０个种进行了开花结果性状的记栽和评价。内容包括果实特征,糖、酸、维生素类、氨基酸、矿质元素含量分析,染色体计数等。分析了种间和种内多样性物存在及在良种选育中利用的可能性。     

中国悬钩子属植物的利用价值概述

主要报道中国悬钩子属植物作为果树种质资源和药用植物的利用价值及果实色素和香味成分的利用潜力。经过十余年的调查１引种栽培和观测评价,发现一些种类可以作为野生小果类果树直接利用,其中２３种４变种是悬钩子类果树选育种的优良种质。据文献记载和民间调查发现。４５种４变种悬钩子植物可以作为中草药治疗多种疾病。对灰白毛莓、高梁泡、蓬、掌叶复盆子和黑莓果实色素的研究结果表明：悬钩子果实色素以醇提法为佳,水提法效果     

甜叶悬钩子(Rubus suavissimus S.Lee)中UDP-糖基转移酶基因的克隆、表达及序列分析

糖基化是植物次生代谢产物生物合成中重要的修饰反应。目前已报道的以二萜为底物的UDP-糖基转移酶(UGT)数量稀少。本研究基于甜叶悬钩子叶片的转录组数据,利用生物信息学分析手段,选定可能具有二萜类催化活性的UDP-糖基转移酶基因进行克隆。最终克隆得到18条UGT基因序列,在大肠杆菌中进行了异源表达,并对克隆的基因进行了初步的序列分析。本研究为进一步挖掘和验证甜叶悬钩子中UGT的功能奠定了基础。     

悬钩子属2中国新记录种

报道了悬钩子属植物的2个中国新记录种,分别为浅裂悬钩子(Rubus polyadenus Cardot)和滇印悬钩子(R.opulifolius Bertol)。浅裂悬钩子发现于云南省东南部的河口和个旧等地,其与黔桂悬钩子(R.feddei H.Lév.Vaniot)较为相近,区别在于该种枝条、叶柄和花序轴密被浅红色具腺长刺毛,叶柄较短,叶片长卵形或近琴形,顶端急尖或渐尖,萼片三角状披针形,顶端长尾尖。滇印悬钩子新发现于云南省西北部的高黎贡山,其与拟覆盆子(R.idaeopsis Focke)较为相近,区别后者在于其小叶3~5枚,花序极短,不足3cm长,花柄很短,整个花序密集缩短成近头状。     

秦巴山区悬钩子植物的种质资源

秦巴山区有野生悬钩子38种12变种,是我国悬钩子属植物比较集中的分布区之一,对秦巴山区悬钩子种质资源的系统调查和综合分析结果表明:1.悬钩子类果实中维生素类（尤其是维生素E）和SOD等生物活性物质的含量异常高,蛋白质、氨基酸、有机酸和矿质元素含量不同程度地高于栽培水果,是一种急待开发利用的野生果树。2.黄果悬钩子、粉枝莓、华中悬钩子、弓茎悬钩子、喜阴悬钩子、插田泡、茅莓、山莓和高粱泡等具有直立生长、植株健壮、少刺或无刺、丰产、抗寒耐旱等经济性状,是悬钩子类果树选种和育种的优良种质材料,其中有些种类还可以直接引种栽培。3.悬钩子植物的美化环境和水土保持作用及药用保健价值也应受到重视。     

天目山自然保护区悬钩子属药用植物资源研究

通过野外调查、采集标本、分类鉴定和查阅文献相结合的方法对浙江省天目山国家级自然保护区悬钩子属植物的药用资源状况进行了较为系统的调查研究。结果发现 :该保护区有悬钩子属植物 1 6种和 1变种 ,它们都可以作为药用植物入药 ,且资源蕴藏量大 ,具有较高的开发利用价值。该项研究有助于该保护区悬钩子属药用植物的开发利用 ,对扩大该属植物药源和发展地方经济都将起到积极的促进作用     

盾叶莓的生物学性状及开发前景

盾叶莓为蔷薇科悬钩子属的多年生落叶灌木,主要分布区在我国苏、浙、皖等省,生长于海拔700 m以上到1 350 m的山区。其地上枝条为两年生,当年生枝条可生长到1～2 m高,秋季落叶经冬季休眠后,次年的5～7月份开花结果后迅速枯死。其果实大,且营养价值高,繁殖容易,是一种具有开发利用价值的野生水果资源。     

悬钩子属植物资源及其利用

悬钩子属Rubus L.植物资源丰富,分布广泛,我国已发表201种98变种,种类之多仅次于北美中心,在分布上自西向东,自南而北有逐渐减少的趋势,西南部为分布中心,利用上有果用和药用两个主要途径,本文在进行国内资源考察的基础上,回顾了国内外悬钩子属植物的利用历史及其栽培化进程,并提出了我国野生悬钩子属植物中具有圈在果用潜力的11个种,本属许多种类是生态适应性很强的地被植物,从保护环境的角度出发,其在水土保持和美化环境方面的价值也值得注意。     

Climate change has only a minor impact on nutrient resorption parameters in a high-latitude peatland

Nutrient resorption from senescing plant tissues is an important determinant of the fitness of plant populations in nutrient-poor ecosystems, because it makes plants less dependent on current nutrient uptake. Moreover, it can have significant “afterlife” effects through its impact on litter chemistry and litter decomposability. Little is known about the effects of climate change on nutrient resorption. We studied the effects of climate change treatments (including winter snow addition, and spring and/or summer warming) on nutrient resorption of four dominant species in a nutrient-poor subarctic peatland. These species were Betula nana (woody deciduous), Vaccinium uliginosum (woody deciduous), Calamagrostis lapponica (graminoid) and Rubus chamaemorus (forb). After five years of treatments both mature and senesced leaf N concentrations showed a small but significant overall reduction in response to the climate treatments. However, the effects were species-specific. For example, in the controls the N concentration in senesced leaves of Calamagrostis (3.0±0.2 mg N g⁻¹) was about four times lower than for Rubus (11.2±0.2 mg N g⁻¹). There were no significant treatment effects on N resorption efficiency (% of the N pool in mature leaves that is resorbed during senescence). The nitrogen resorption efficiency of Calamagrostis (about 80%) was higher than in the other three species (about 60%). Thus, climate change has only a minor impact on nutrient resorption parameters. However, given the substantial interspecific differences in these parameters, substantial changes in plant–soil feedbacks may be expected as a result of the observed changes in the species composition of high-latitude vegetation. These changes are species-specific and thus difficult to predict.     

Nutrient content and seasonal fluctuations in the leaf component of coark-oak (Quercus suber L.) litterfall

Nutrient content and seasonality of the leaf component in cork-oak litterfal were studied over a two year period in two cork-oak forest sites differing in biomass and edaphic condition in the north-eastern Iberian peninsula. Fallen senescent leaves compared to young leaves showed higher non-mobile nutrient concentrations and lower mobile nutrient concentrations, specially P, N, K, and Mg. At both sites, seasonal fluctuations affected both leaf production and leaf mineral content. The maximum leaf fall period correspond to the start of the vegetative growth and to the lowest N and P concentration in the falling leaves. The opposite was true for the winter, when litterfal was minimal and N and P content in falling leaves was at a maximum.The comparison between falling leaves and canopy leaves suggests that the analysis of fallen leaves can be a useful measure of N and P nutrition in cork-oak. We found site dependent differences in nutrient content and nutrient remobilization. In comparison with Q. ilex, although litter production was in the same range, nutrient retranslocation was greater for Q. suber.     

Phylogeny of Rubus (rosaceae) based on nuclear ribosomal DNA internal transcribed spacer region sequences

We used nuclear ribosomal DNA internal transcribed spacer region (ITS 1 - 5.8S - ITS 2; ITS) sequences to generate the first phylogeny of Rubus based on a large, molecular data set. We sampled 57 taxa including 20 species of subgenus Rubus (blackberries), one to seven species from each of the remaining 11 subgenera, and the monotypic and closely related Dalibarda. In Rubus, ITS sequences are most informative among subgenera, and variability is low between closely related species. Parsimony analysis indicates that Rubus plus Dalibarda form a strongly supported clade, and D. repens may nest within Rubus. Of the subgenera with more than one species sampled, only subgenus Orobatus appears monophyletic. Three large clades are strongly supported: one contains all sampled species of nine of the 12 subgenera; another includes extreme Southern Hemisphere species of subgenera Comaropsis, Dalibarda, and Lampobatus; and a third clade consists of subgenus Rubus plus R. alpinus of subgenus Lampobatus. Rubus ursinus appears to be a hybrid between a close relative of R. macraei (subgenus Idaeobatus, raspberries) and an unidentified subgenus Rubus species. ITS sequences are generally consistent with biogeography and ploidy, but traditionally important morphological characters, such as stem armature and leaf type, appear to have limited phylogenetic value in Rubus.     

Effects of leaf maturity and wind stress on the nutrition of the generalist caterpillar Lymantria dispar feeding on poplar

The growth rates of insect herbivores commonly decrease when they feed on mature leaves due to the combined effects of several nutritional and physiological mechanisms. Environmental stresses during leaf development may also decrease herbivore performance. The present study tests two main hypotheses to help clarify the importance of these factors for the nutrition and growth of an insect herbivore: (i) decreases in nutrient levels, consumption rates and nutrient assimilation efficiencies impact negatively on herbivores feeding on mature leaves and (ii) wind stress has a negative impact on herbivores feeding on mature leaves. The results show that mature poplar (Populus alba × Populus tremula) leaves have decreased levels of protein and increased levels of fibre, and that growth rates of gypsy moth (Lymantria dispar L.) are decreased on mature leaves in association with decreased consumption rates. However, in contrast to the first hypothesis, protein and carbohydrate are assimilated efficiently (74–82% and 84–87%, respectively) from immature and mature poplar leaves. The larvae are able to chew mature leaves as efficiently as immature leaves, potentially maximizing nutrient extraction. By contrast to the second hypothesis, wind‐stressed leaves have no significant detrimental effects on nutrient assimilation efficiencies, and the lower growth rates of L. dispar larvae feeding on mature wind‐stressed leaves can be explained by lower consumption rates. Therefore, the availability of nutrients to herbivores feeding on mature tree leaves is not necessarily impacted by lower assimilation efficiencies, even when leaves develop under wind stress. These results help explain some of the large variation between the nutritional qualities of trees for forest Lepidoptera.     

STUDIES IN RUBUS VIRUS DISEASES

Raspberry leaf mottle virus is acquired by Amphorophora rubi in feeding periods of 1/2-2 hr. Longer feeding periods cause no significant fluctuations in infectivity. During continuous feeding on healthy plants, infectivity declines rapidly after 2 hr., but persists for at least 5 hr. if aphids are transferred frequently to fresh healthy plants. The estimated probability of infection by single aphids is 1 in 20. Rarely more than 50% of test plants, Rubus occidentalis , seedlings became infected, and this is thought to be due mainly to variation in plant susceptibility. Young leaves of infected Norfolk Giant are, however, better sources of virus than older leaves.     

A meta‐analysis of the effects of nutrient enrichment on litter decomposition in streams

The trophic state of many streams is likely to deteriorate in the future due to the continuing increase in human‐induced nutrient availability. Therefore, it is of fundamental importance to understand how nutrient enrichment affects plant litter decomposition, a key ecosystem‐level process in forest streams. Here, we present a meta‐analysis of 99 studies published between 1970 and 2012 that reported the effects of nutrient enrichment on litter decomposition in running waters. When considering the entire database, which consisted of 840 case studies, nutrient enrichment stimulated litter decomposition rate by approximately 50%. The stimulation was higher when the background nutrient concentrations were low and the magnitude of the nutrient enrichment was high, suggesting that oligotrophic streams are most vulnerable to nutrient enrichment. The magnitude of the nutrient‐enrichment effect on litter decomposition was higher in the laboratory than in the field experiments, suggesting that laboratory experiments overestimate the effect and their results should be interpreted with caution. Among field experiments, effects of nutrient enrichment were smaller in the correlative than in the manipulative experiments since in the former the effects of nutrient enrichment on litter decomposition were likely confounded by other environmental factors, e.g. pollutants other than nutrients commonly found in streams impacted by human activity. However, primary studies addressing the effect of multiple stressors on litter decomposition are still few and thus it was not possible to consider the interaction between factors in this review. In field manipulative experiments, the effect of nutrient enrichment on litter decomposition depended on the scale at which the nutrients were added: stream reach > streamside channel > litter bag. This may have resulted from a more uniform and continuous exposure of microbes and detritivores to nutrient enrichment at the stream‐reach scale. By contrast, nutrient enrichment at the litter‐bag scale, often by using diffusing substrates, does not provide uniform controllable nutrient release at either temporal or spatial scales, suggesting that this approach should be abandoned. In field manipulative experiments, the addition of both nitrogen (N) and phosphorus (P) resulted in stronger stimulation of litter decomposition than the addition of N or P alone, suggesting that there might be nutrient co‐limitation of decomposition in streams. The magnitude of the nutrient‐enrichment effect on litter decomposition was higher for wood than for leaves, and for low‐quality than for high‐quality leaves. The effect of nutrient enrichment on litter decomposition may also depend on climate. The tendency for larger effect size in colder regions suggests that patterns of biogeography of invertebrate decomposers may be modulating the effect of nutrient enrichment on litter decomposition. Although studies in temperate environments were overrepresented in our database, our meta‐analysis suggests that the effect of nutrient enrichment might be strongest in cold oligotrophic streams that depend on low‐quality plant litter inputs.     

Does the Gradualness of Leaf Shedding Govern Nutrient Resorption from Senescing Leaves in Mediterranean Woody Plants?

To reveal the environmental and substrate quality effects on decomposition process and enzyme activities, litterbag experiments containing Nuphar and Carex leaves, Nuphar rhizome, and Ranunculus shoot, were carried in five-subalpine marshes in Lake Tahoe basin, USA. Alkaline phosphatase, β-glucosidase, and β-xylosidase activities were determined by a fluorogenic method using methyumbelliferyl substrates. Carex leaves, Nuphar rhizome and leaves, and Ranunculus shoots lost, respectively, 33, 67, 82 and 93% of original dry weight over 268 days. Decay rates were different among substrates but not among marshes. Nitrogen and carbon contents increased during the first 58 days and subsequently remained stable. Phosphorus content was stable during the experimental period except for a decrease in the first 16 days in Nuphar shoots. Enzyme activities in decomposing Carex and Nuphar leaves in four marshes were not significantly affected by environmental conditions. β-glucosidase and β-xylosidase activities in decomposing Carex leaves increased with time, but in other plant tissue these enzyme activities remained stable during experimental period. Enzyme activities were significantly different among decomposing substrates. Alkaline phosphatase activity was highest in Nuphar leaves (ca. 1286 μ-mole h⁻¹ g DW −1) but lower and similar in other plant tissues (ca. 100 and 10 μ-mole h −1 g DW −1, respectively). This study showed differences in decay rates and enzyme activities rely on substrate and not the environment conditions of the study area. Decomposition rates in the early stage of decomposition were related to cumulative enzyme activities.