Waterlogging is a major abiotic stress for riparian plants and poses a serious threat to their survival. Salix viminalis L., an important riparian species, exhibits strong waterlogging tolerance, with aquatic adventitious roots (AAR) playing a key role. However, how their root system architecture (RSA) responds dynamically to waterlogging and the associated structural basis for resource acquisition remain unclear. Waterlogging was simulated to induce AAR in S. viminalis, and dynamic morphological, topological, fractal, and anatomical traits were systematically analyzed to suggest potential resource-acquisition strategies based on structural proxies. The primary roots (PR) showed significant reductions in total root length (TRL), specific root length (SRL), root surface area (SA), specific root surface area (SRSA), root volume (RV), root tip number (RT), and root fork number (RF), while average root diameter (RAD) remained unchanged. In contrast, all metrics in AAR increased significantly, while RAD decreased, expanding the interface for resource acquisition. In topology, the topological index (TI) of AAR progressively decreased, with the architecture shifting from a herringbone to a dichotomous pattern. In fractal traits, AAR exhibited increased fractal dimension (FD) and fractal abundance (FA), indicating higher complexity and space-filling capacity. Anatomically, PR maintained function early in waterlogging via epidermal densification and cortical aerenchyma formation but structural deteriorated over time. AAR, however, developed well-structured aerenchyma. This study reveals the adaptive changes of root systems in waterlogging-tolerant plants to soil environments under waterlogged conditions, providing valuable reference for the application of S. viminalis in riparian ecosystem restoration.

Dendrobium nobile is a prized orchid species with both medicinal and ornamental values, known for accumulating flavonoids that contribute to its bioactivity and flower pigmentation. Chalcone isomerase (CHI), a key enzyme in the flavonoid biosynthetic pathway, catalyzes the conversion of chalcone to naringenin, thereby promoting the production of anthocyanins and other flavonoids. In this study, we present the first systematic analysis of the CHI gene family in D. nobile, classifying them into two subfamilies. Expression profiling revealed that DnCHI1, a type IV CHI, is highly expressed in petals, suggesting a potential role in anthocyanin metabolism. Heterologous transient overexpression assays showed that DnMYB90 significantly downregulated endogenous PeCHI expression and reduced anthocyanin accumulation, whereas DnCHI1 overexpression resulted in a 15-fold increase in anthocyanin content. Dual-luciferase reporter and yeast one-hybrid assays further confirmed that DnMYB90 acts as a transcriptional repressor of DnCHI1. These results provide new insights into the regulatory module in anthocyanin biosynthesis in D. nobile, highlighting the functional divergence of CHI genes and their interaction with MYB transcription factors.

Dendrobium jizhuyeense, a new species from Sichuan, China, is described and illustrated in this study. Morphological study indicates that D. jizhuyeense is similar to D. hancockii, but differs in having oblong sepals, obovate-elliptic petals and an obovate lip, including a smaller stem, smaller leaf and different flower type. Molecular analyses based on nuclear and plastid markers indicate that D. jizhuyeense is closely related to D. hancockii, belonging to section Holochrysa.

Flooding is one of the most common abiotic stresses that plants suffer. Roots are organs that directly sense anoxic environments, but there are few researches on the response of roots to flooding. In this research, the responses of male and female Salix viminalis plants to flooding were investigated by examining the morphological and physiological responses of roots. Our results showed that primary roots (PRs) growth was significantly inhibited and damaged to a certain extent. However, adventitious roots (ARs) formed in a short time and were essential for plants to endure flooding. To cope with flooding stress, the antioxidant enzyme activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), ascorbate peroxidase (APX) increased. Although Pro-contents increased, they were too low to contribute significantly to osmotic adjustment. The anaerobic respiration metabolic pathway was also activated, as proven by increased pyruvate decarboxylase (PDC), alcohol dehydrogenase (ADH), and lactate dehydrogenase (LDH) activities, and the ethanol metabolism pathway might have a key function in adapting to the hypoxic environment for S. viminalis. In addition, increased non-structural carbohydrates (NSCs) of starch and soluble sugar (SS) contents indicated that quiescence strategy might exist in S. viminalis. Overall, there were no significant differences between males and females under flooding stress, and both genders exhibited strong adaptability to the flooding environment. Therefore, two genders of S. viminalis could be applied in the riparian zone.

[目的]研究蒿柳(Salix viminalis)雌雄株幼苗在生长季不同阶段的生长与防御差异,为雌雄株差异研究及其在生产实践中的选择性应用提供指导.[方法]以蒿柳1年生雌雄扦插苗为研究对象,在大田中采用完全随机区组设计,于6-10月(6月5日、7月3日、8月4日、9月7日和10月5日)对雌雄株幼苗的生长、光合作用参数、光合色素含量、化学防御物质含量以及防御酶活性等测定后进行动态分析,比较二者差异.[结果]蒿柳雌雄幼苗株高在6月、地径在6月和7月无显著差异,其他时间株高和地径均为雄株显著高于雌株.6月雌雄株间的净光合速率(Pn)和蒸腾速率(Tr)无显著差异,7-10月均表现为雄株显著高于雌株;6-9月雌雄株间气孔导度(Gs)无显著差异,仅在10月雄株显著高于雌株;6-10月整个生长季雌雄株间胞间CO2浓度(Ci)差异均不显著.雌雄株间叶绿素a(Chl a)、叶绿素b(Chl b)和类胡萝卜素(Car)含量在6月差异均不显著,7-10月各光合色素含量均为雄株显著高于雌株.雌雄株间多酚和缩合单宁含量在生长季均无显著差异,但雄株的SOD(6月除外)、POD、PPO和PAL(6月除外)活性均显著高于雌株.[结论]在有胁迫因素存在的自然环境中,蒿柳雌雄株幼苗防御物质含量无显著差异,但雌株防御酶活性较低、生长相对缓慢,可能在繁殖与生长、防御间存在进化的权衡.蒿柳雄株生长相对较快,且可解决飞絮问题,在实际应用中可优先选用.

Amygdalin, a naturally occurring compound, is one of the main active ingredients of the Chinese raw bitter almond. The variation in amygdalin composition of seed kernels among the six almond species was determined, and relationships with geoenvironmental factors were analyzed. The amygdalin content exhibited great diversity, ranging from 0.0004 to 9.73 g/100 g. The highest level of amygdalin was detected in Tangut almond, with 5.45-9.73 g/100 g. The other kernels showed a range from 3.14 to 6.80 g/100 g in wild almond and from 3.00 to 4.22 g/100 g in longstalk almond. Amygdalin in common almond was almost undetectable. Factor analysis showed that amygdalin content in Prunus spp. kernels increased with altitude and decreased with the degree of aspect. Many environmental factors were closely related to amygdalin content, including annual precipitation (Bio12), UV intensity, and topsoil base saturation (T_BS), which all had a significant effect on amygdalin content. The amygdalin content is closely related to rainfall indicators, especially annual precipitation (Bio12), with the highest factor analysis value (3.63). Water regulates amygdalin in diverse ways. Since amygdalin is water-soluble, water can reduce the inhibitory effect of amygdalin on germination and regulate the synthesis of amygdalin at the late stage of germination by activating the amygdalin synthesis genes CYP79D16 and CYP71AN24. This study expands the understanding of amygdalin in almond resources and provides the direction for the regulation of amygdalin.

The compatibility of mycorrhizal fungi with the early growth stage of orchids is essential for their growth. In this study, the compatibility and promotion effects of 14 Tulasnella strains from different hosts were studied by co-culturing them with the protocorms of Dendrobium crepidatum, which has high ornamental and economic value in China. The ITS–LSU–SSU–TEF combined sequence analysis divided the 14 strains into three clades belonging to Tulasnella calospora (clades A and B) and Tulasnella asymmetrica (clade C). All the strains were compatible with D. crepidatum protocorms within 90 d of the co-culture. Strain T12 in Clade A had a significantly higher (p < 0.05) effect on the biomass and morphology of D. crepidatum, and strain T13 in Clade C had a significantly lower (p < 0.05) effect than the other strains. Through morphological principal component analysis, we constructed a hierarchical cluster analysis tree, which was consistent with the phylogenetic tree of these 14 strains at the clade level. Orthogonal partial least squares-discriminant analysis showed that these strains have an important effect on the plant height, root number, and length of D. crepidatum. The findings of this study will contribute to the identification of Tulasnella strains, conservation of D. crepidatum resources, and commercial utilization of mycorrhizal technology.

[目的]药用石斛花朵有解郁补虚、清热消炎功效,常用于茶饮、食疗.研究5种石斛花朵的挥发性成分及其含量,探明其香气组成,以期为石斛花保健功效的开发提供参考.[方法]采用顶空固相微萃取(HS-SPME)结合气相色谱-质谱联用(GC-MS)技术,分析了肿节石斛、棒节石斛、玫瑰石斛、束花石斛、报春石斛花朵的挥发性成分.[结果]5种石斛花朵中,共鉴定出110个挥发性成分,主要成分为烷类、烯类、醇类、酮类等.肿节石斛、棒节石斛、玫瑰石斛、束花石斛的花朵挥发性成分皆为首次测定.[结论]不同石斛花朵的芳香成分不尽相同,肿节石斛为芳樟醇、罗勒烯、β-石竹烯;棒节石斛为罗勒烯、β-石竹烯;玫瑰石斛为d-柠檬烯、蒎烯、罗勒烯;束花石斛为罗勒烯、蒎烯、芳樟醇.棒节石斛和肿节石斛中含有具有解郁功效的β-石竹烯.

Akebia quinata , also known as chocolate vine, is a creeping woody vine which is used as Chinese herbal medicine, and found widely distributed in East Asia. At present, its wild resources are being constantly destroyed. This study aims to provide a theoretical basis for the resource protection of this plant species by analyzing the possible changes in its geographic distribution pattern and its response to climate factors. It is the first time maximum entropy modeling (MaxEnt) and ArcGIS software have been used to predict the distribution of A. quinata in the past, the present, and the future (four greenhouse gas emission scenarios, namely, SSP1-2.6, SSP2-4.5, SSP3-7.0, and SSP5-8.5). Through the prediction results, the impact of climate change on the distribution of A. quinata and the response of A. quinata to climate factors were analyzed. The results showed that the most significant climatic factor affecting the distribution pattern of A. quinata was the annual precipitation. At present, the suitable distribution regions of A. quinata are mainly in the temperate zone, and a few suitable distribution regions are in the tropical zone. The medium and high suitable regions are mainly located in East Asia, accounting for 51.1 and 81.7% of the worldwide medium and high suitable regions, respectively. The migration of the geometric center of the distribution regions of A. quinata in East Asia is mainly affected by the change of distribution regions in China, and the average migration rate of the geometric center in each climate scenario is positively correlated with the level of greenhouse gas emission scenario.

中国是世界石斛属(Dendrobium)植物分布中心,其主要分布在云贵川等地区.采用扩增片段长度多态性(AFLP)分子标记方法,研究了石斛属92个种质的遗传多样性和亲缘关系.从24对引物组合中筛选出10对引物组合进行扩增,共扩增出2 329个位点,其中多态位点2 307个,占总扩增位点的99.04％.聚类分析将92个石斛种质,分为4个类群,种间遗传分化显著.AFLP分子标记将菱唇石斛和西畴石斛划为石斛组、金耳石斛划为寡花组,且研究结果表明,茎的形态和质地为石斛分类的重要性状,花的唇瓣和茎节的膨大非石斛分类的主要因素.

石斛作为我国"九大仙草"之首,发展势头迅猛,种植面积居草本中药材第21名,已成为我国的大宗药材.发布我国石斛产业最新数据,对目前我国石斛种质资源进行系统梳理,概括分析石斛产业发展脉络和历程,梳理与石斛产业发展息息相关的药食同源、新资源食品等政策,为后期石斛产业的发展和产品开发提供参考.我国共有石斛野生资源92种,石斛产业种植总面积达45.4万亩(1亩≈666.67 m2),综合产值逾500亿元.石斛种植面积较大的省份有云南、贵州、浙江等,石斛主产区为云南德宏、保山,浙江乐清,安徽霍山,贵州赤水、安龙、锦屏等.药用石斛种类主要为铁皮石斛、金钗石斛、霍山石斛、紫皮石斛等.

Almond resources are widely distributed in Central Asia; its distribution has not been studied in detail. Based on the first-hand data of field investigation, climate variables and chloroplast genome data, climatic characteristics of six almond species in China were analyzed, and the global distribution and evolutionary relationship were predicted. The six almond species are concentrated between 27.99°N and 60.47°N. Different almond species have different climatic characteristics. The climate of the almond species distribution has its characteristics, and the distribution of almond species was consistent with the fatty acid cluster analysis. All the test AUC (area under curve) values of MaxEnt model were larger than 0.92. The seven continents except for Antarctica contain suitable areas for the six almond species, and such areas account for approximately 8.08% of the total area of these six continents. Based on the analysis of chloroplast DNA and the distribution characteristics, the evolutionary relationship of the six almond species was proposed, which indicated that China was not the origin of almond. In this study, the construction of a phylogenetic tree based on the chloroplast genome and the characteristics of geographical distribution were constructed. The six almond species in China may have evolved from “Unknown almond species” through two routes. The MaxEnt model for each almond species provided satisfactory results. The prediction results can provide the important reference for Prunus dulcis cultivation, wild almond species development and protection.

在山桐子(Idesia polycarpa Maxim.)自然分布区南界(广东省乳源县)、北界(河北省易县)及主要集中分布区(四川省的芦山县和夹江县以及贵州省道真县)选择16个山桐子样本,对其完整果穗和成熟果实的性状(包括14个表型性状和果实含油率)进行变异分析、遗传多样性分析和相关性分析,并基于表型性状的主成分分析结果对供试样本进行聚类分析.结果表明:不同山桐子样本间果穗和果实性状差异极显著(P<0.001),各性状的变异系数为2.75％～58.23％,Simpson指数为0.75～0.88,Shannon-Weaver指数为2.30～3.13.相关性分析结果表明:果穗长、果穗宽、单果穗质量、单果穗果实质量和果穗小枝长间基本呈显著(P<0.05)或极显著(P<0.01)正相关,果实占比、单果质量、果实纵径、果实横径、单果种子质量和单果果肉质量间均呈极显著正相关,但果穗和果实表型性状与果实含油率的相关性均不显著.主成分分析结果表明:前4个主成分的累计贡献率为92.281％,能够反映山桐子果穗和果实表型性状的大部分信息;第1、第2、第3和第4主成分的贡献率分别为40.863％、31.979％、10.477％和8.962％,分别主要反映山桐子的果实大小、果穗长度和疏密度、果实形状及果柄长特征.聚类分析结果表明:供试样本可分为中果中疏穗中柄型(Ⅰ)、小果中疏穗长柄型(Ⅱ)、大果长疏穗中柄型(Ⅲ)及中果短密穗中柄型(Ⅳ)4个类群.其中,Ⅲ类群的果实含油率最高(31.07％),Ⅳ类群的果实含油率最低(21.28％).研究结果显示:山桐子果穗和果实性状变异丰富,遗传多样性较高;果实大小和形状、果穗长度和疏密度以及果柄长度是影响山桐子果穗和果实表型多样性的关键性状;大果型和(或)长穗型山桐子具有一定的油用开发优势.

Bark chloroplasts play important roles in carbon balancing by recycling internal stem CO2 into assimilated carbon. The photosynthetic response of bark chloroplasts to interior stem environments has been studied recently in woody plants. However, the molecular regulatory mechanisms underlying specific characteristics of bark photosynthesis remain unclear. To address this knowledge gap, differences in the structure, photosynthetic activity and protein expression profiles between bark and leaf chloroplasts were investigated in Salix matsudana in this study. Bark chloroplasts exhibited broader and lower grana stacks and higher levels of starch relative to leaf chloroplasts. Concomitantly, decreased oxygen evolution rates and decreased saturated radiation point were observed in bark chloroplasts. Furthermore, a total of 293 differentially expressed proteins (DEPs) were identified in bark and leaf chloroplast profile comparisons. These DEPs were significantly enriched in photosynthesis-related biological processes or Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways associated with photosynthesis. All 116 DEPs within the KEGG pathways associated with photosynthesis light reactions were downregulated in bark chloroplasts, including key proteins responsible for chlorophyll synthesis, light energy harvesting, nonphotochemical quenching, linear electron transport and photophosphorylation. Interestingly, seven upregulated proteins involved in dark reactions were identified in bark chloroplasts that comprised two kinds of malic enzymes typical of C4-type photosynthesis. These results provide comprehensive proteomic evidence to understand the low photochemical capability of bark chloroplasts and suggest that bark chloroplasts might fix CO2 derived from malate decarboxylation.

目的 对肿节石斛(Dendrobium pendulum Roxb.)茎、叶、花进行定性和定量研究.方法 采用超高效液相色谱四极杆串联飞行时间质谱联用法(UPLC-Q-TOF-MS)技术,采用甲酸-乙腈为流动相,梯度洗脱,ESI,质量扫描范围:m/z 50～1 000.结果 分别鉴定为dendrocandin L(1)、芦丁(2)、金丝桃苷(3)、densiflorol A(4)、5-[2-(4-羟基-3-甲氧基苯基)乙基]-1,3-苯二酚(5)、芹菜素(6)、柚皮素(7)、3-[(E)-2-(5-羟基-3-甲氧基-1-环己-2,4-二烯基)乙烯基]-2,6-二-甲氧基苯酚(8)、longicornuol A(9)、aloifol I (10)、coelonin(11)、isomoniliformine A (12)、denchryside A(13),包含联苄、黄酮、菲类、联菲等.肿节石斛花中以联苄类成分为主,叶中芦丁含量高达23.498 μg·g-1.结论 3-[(E)-2-(5-羟基-3-甲氧基-1-环己-2,4-二烯基)乙烯基]-2,6-二甲氧基苯酚为首次在兰科植物中分离得到;除芦丁外,12个成分均为首次从肿节石斛中分离得到.

This study first systematically investigated the differences and correlations of seed oil content, fatty acid (FA) composition and regional agro-climate conditions of Akebia trifoliata from 25 representative distribution areas throughout China. A. trifoliata seeds were rich in oil (30.2 %-48.8 %), but significant (P < 0.01) variations were detected among their FA profiles. Ten major FAs, dominated by oleic acid (OA, 155.9-261.5 mg g(-1), 36.6 %-45.2 %), linoleic acid (LA, 113.8-156.4 mg g(-1), 23.5 %-30.8 %) and palmitic acid (PA, 101.8-149.1 mg g(-1), 20.3 %- 25.7 %), were detected and quantified by GC-MS. Noticeably, their ratios of saturated: monounsaturated: polyunsaturated FAs were 1:1.5:1, which was in line with the World Health Organization's recommendation. Latitude, temperature and moisture were the core factors affecting oil accumulation in A. trifoliata. Opposite to PA and LA, the OA and oil content were strongly negatively correlated with high temperature and precipitation, and were higher in northern and eastern seeds. According to the results of correlation and cluster analysis, A. trifoliata germplasms and agro-climate characters of six regions (from cluster III) around latitude 35 degrees N, where were much colder and drier, and with larger diurnal temperature fluctuations than other regions, were more desirable for commercial cultivation of A. trifoliata for oil processing and for breeding of improved cultivars.

石斛是益胃生津,滋阴补虚的中药,有提高免疫力、抗氧化等功效,含有丰富的黄酮活性成分,具有较高保健价值.从多个石斛中共分离得到89个黄酮活性成分,主要分为黄酮类、黄烷酮类、黄酮醇类3种.其中黄酮类成分40个,苷元类型主要为芹菜素和圣金草素;黄烷酮类成分20个;黄酮醇类成分15个,苷元类型主要为山柰酚和槲皮素.铁皮石斛及个别种还含有二氢黄酮醇类、花色素类、查尔酮类等黄酮类型成分.含有黄酮活性成分的石斛属植物有34个种,铁皮石斛含38个黄酮成分,霍山石斛含28个黄酮成分,紫皮石斛(齿瓣石斛)含19个黄酮成分,大苞鞘石斛含12个黄酮成分,球花石斛含有5个黄酮成分,叠鞘石斛和棒节石斛各含有4个黄酮活性成分.霍山石斛中含有大量以芹菜素为苷元的黄酮活性成分,紫皮石斛中含有多数以山柰酚或槲皮素为苷元的黄酮活性成分.常见的黄酮活性成分有柚皮素、槲皮素、芦丁等,具有抗氧化、降血糖、可改善血液循环、降低胆固醇,对心血管系统具有保护作用等药理活性作用.笔者拟对中药石斛黄酮活性成分的数量、类型、生理功能等研究现状进行了综述,以期推动药用石斛业内对石斛黄酮的关注,有助于挖掘石斛属植物在药效、食品领域的价值.

Aims It is well established that mycorrhizal symbiosis can affect plant-plant interactions. On the other hand, how intraspecific plant interactions influence communities of arbuscular mycorrhizal fungi (AMF) is still very poorly understood. Methods We applied 454 pyrosequencing to determine the responses of AMF communities to intraspecific shoot and root interactions using Medicago sativa L. as host plant. Results We found that intraspecific plant interaction caused significant variation in the structure of the AMF community assessed from roots but not from soil. Intraspecific root system interaction resulted in significantly elevated AMF species richness, greater total mycorrhizal and arbuscular colonization, and a larger root:shoot ratio compared to plants experiencing intraspecific shoot interaction or no interaction. Intraspecific shoot interaction resulted in significantly depressed AMF species richness. Conclusions Our results support two hypotheses. The first is that increased AMF species richness in plants experiencing intraspecific root interaction originates from competitive release provided by high root density. The second is that shoot interaction leads to reduced allocation to root systems, increasing the stringency with which host plants selectively reward the most cooperative fungi. Because intraspecific interactions among host plants can influence the structure of their AMF community, interactions among species in complex plant communities may influence AMF community structure in addition to a plant diversity effect.

肿节石斛(Dendrobium pendulum)是兰科石斛属多年生附生植物,具有较高保健价值和药用潜力.生物碱是石斛的特征功能成分,本研究利用超高效液相色谱-四级杆飞行时间质谱(UPLC-Q-TOF-MS)技术,研究了肿节石斛茎、花、叶中生物碱的成分和相对含量.通过甲醇法和氯仿法共表征出15个生物碱成分,分属三种类型,其中7个八氢中氮茚类生物碱:玫瑰石斛碱(1)、玫瑰石斛碱C(2)、玫瑰石斛胺(3)、玫瑰石斛啶碱(5)、玫瑰石斛碱B(8)、玫瑰石斛碱D(9)、玫瑰啶碱B(10);7个倍半萜类生物碱:石斛碱(4)、石斛胺碱(6)、石斛酮碱(7)、红星碱A(11)、N-异戊烯石斛星碱(12)、N-异戊烯石斛碱(13)、棒节碱D(14);1个酰胺类生物碱:N-p-桂皮酸酰酪胺(15).该研究首次发现肿节石斛中生物碱存在,含量以八氢中氮茚类生物碱为主,以玫瑰石斛啶碱、玫瑰石斛碱B含量高.植株不同部位生物碱,由高到低依次为花、叶、茎.花中生物碱以八氢中氮茚类为主,茎中生物碱以倍半萜类为主.

As a source of genetic variation, almond germplasm resources are of great significance in breeding. To better reveal the mutation characteristics and evolution patterns of the almond chloroplast (cp) genome, the complete cp genomes from six almond species were analyzed. The lengths of the chloroplast genome of the six almond species ranged from 157,783bp to 158,073bp. For repeat sequence analysis, 53 pairs of repeats (30bp or longer) were identified. A total of 117 SSR loci were observed, including 96 polymorphic SSR loci. Nine highly variable regions with a nucleotide variability (Pi) higher than 0.08, including rps16, rps16-psbK, atpF-atpH, rpoB, ycf3-rps4, rps4-ndhJ, accD-psaI and rps7-orf42 (two highly variable regions) were located. Based on the chloroplast genome evolution analysis, three species (P. tenella, P. pedunculata and P. triloba) and wild cherry (P. tomentosa) were grouped into clade I. Clade II consisted of two species (P. mongolica and P. tangutica) and wild peach (P. davidiana). Clade III included the common almond (P. dulcis), cultivated peach (P. persica) and GanSu peach (P. kansuensis). This result expands the researchers' vision of almond plant diversity and promotes an understanding of the evolutionary relationship among almond species. In brief, this study provides abundant resources for the study of the almond chloroplast genome, and has an important reference value for study of the evolution and species identification of almond.