BACKGROUND:Camellia oleifera Abel. is one of the four major woody oil species whose seeds produce high-grade edible oil. In recent years, the planting area of Camellia oleifera is increasing in China. However, in the process of cultivation, due to the high fruit load, the Camellia oleifera tree has small fruit and poor quality. In previous studies, we explored the optimal leaf-fruit ratio. In this study, the changes of molecular regulation mechanism of Camellia oleifera under different leaf-fruit ratios were revealed by combining physiological indexes with transcriptome data. RESULT:The physiological results showed that the content of MDA and starch in leaves increased significantly with the decrease in the leaf-to-fruit ratio. The results of transcriptome showed that there was a close relationship between leaf-fruit ratio and phenylpropanoid biosynthesis pathway. With the decrease of leaf-fruit ratio, the expression of genes related to lignin and flavonoid biosynthesis increased significantly, which promoted the synthesis of lignin and flavonoid. CONCLUSIONS:Combining physiological indicators and transcriptomics, we demonstrated that leaf-fruit ratio can significantly affect the normal growth of plants. When the fruit load is too high, the fruit as a 'sink' will consume a large amount of nutrients in the plant body and promote the biosynthesis of lignin and flavonoids in the body. The results provide a more reliable scientific basis for the study of cultivation and management of Camellia oleifera.

Dian Hong rose is the largest edible rose variety in Yunnan, rich in glutathione, in addition to ornamental value, is also an important raw material in the food flavor industry. In recent years, due to the serious soil pollution in China, there are few reports on the physiological and biochemical reactions of rose under heavy metal stress, and the heavy metal tolerance of Dian Hong rose remains to be studied. In this experiment, the photosynthetic and physiological effects of chromium and cadmium on Dian Hong rose were investigated by single stress treatment (single stress treatment refers to the addition of only one heavy metal to the treatment). The study results demonstrated that as the treatment concentrations of chromium (Cr) and cadmium (Cd) increased, the content of soluble sugars, soluble proteins, malondialdehyde, peroxidase, and catalase in the leaves correspondingly augmented. The pigment content of leaves decreased with the increase of treatment concentration.The daily variation trends of net photosynthetic rate (Pn) and transpiration rate (Tr) of leaves were similar, showing A trend of first increasing and then decreasing. When the concentration of Cr ion in treatment A exceeded 300 mg•Kg− 1, and the concentration of Cd in treatment B exceeded 50 mg•Kg− 1, the net photosynthetic rate of leaves was worse than that in control group, and the net photosynthetic rate gradually decreased with the increase of stress concentration. The above studies indicated that the plant damage caused by metabolic imbalance could be reduced by increasing osmotic regulatory substances in leaves and inducing active oxygen scavenging system when the rose was stressed by heavy metals. In a certain concentration range, its growth trend was better than that of the control group, which proved that the Dian Hong rose had a certain degree of heavy metal stress tolerance.

Abstract Litsea cubeba (Lour.) Pers. is an important spice plant in southern China. The whole plant of Litsea cubeba contains essential oils, among which the fruit has the highest essential oil content. And there is a significant market demand and widespread use of essential oil of Litsea cubeba fruit. However, there are few systematic studies on the growth and development of the Litsea cubeba fruit. This study aims to determine the regularity of annual changes in fruit morphology, essential oil content, and components of Litsea cubeba essential oil to determine the optimal harvest period and improve the utilization efficiency of Litsea cubeba resource. The results show that the annual change of fruit morphology of Litsea cubeba was consistent with the double "S" curve, which shows a general trend of rapid growth first, then slow growth, and finally rapid growth again. While the annual change of the essential oil of Litsea cubeba fruits was consistent with a single "S" curve, which shows a general trend of slow growth first, then rapid growth, and finally decreasing rapidly. Correlation analysis showed a significant negative correlation between morphological changes and essential oil accumulation in Litsea cubeba fruit. Combining the growing periods of fruit morphology and essential oil accumulation, the growth and development of Litsea cubeba fruit can be divided into four general periods: the first rapid growth period (rapid growth in fruit diameter and fruit weight with slow accumulation of essential oil), the essential oil accumulation period (rapid accumulation of essential oil with slow growth in fruit diameter and fruit weight), the second rapid growth period (fruit diameter and fruit weight increased rapidly for the second time while the essential oil content started to decrease), and the shriveling period (fruit diameter and weight and essential oil content all decreased rapidly). This study further confirmed that citral was the highest component in the essential oil of Litsea cubeba. When citral extraction is needed, the fruit can be harvested 139–149 days after anthesis.

【Objective】The growth and physiological changes of poinsettia（Euphorbia pulcherrima Willd.） were observed, which gave a discussion on the potential of phytoremediation using poinsettia and provided a new idea for the treatment of Zn-contaminated soils.【Method】Poinsettia cutting seedlings were used as experimental materials, and the pot experiment was carried out by incomplete randomized block design.The treatments with six Zn-pollution concentrations in soils were set: CK（0 mg/kg, without adding Zn reagent）, T1（200 mg/kg）, T2（300 mg/kg）, T3（500 mg/kg）, T4（800 mg/kg） and T5（1000 mg/kg）（dry mass）, respectively, repeated four times.Plant height and ground diameter of poinsettia were measured every 14 days during the experiment.The biomass, root morphology index（root length, total projection area, root surface area, average diameter, root volume, and root tip number）, leaf number, leaf area, chlorophyll content, malondialdehyde（MDA） content, and the accumulation content, tolerance index（TI）, and transport factor（TF） of poinsettia for Zn were analyzed after 112 days of sampling.【Result】（ⅰ） Compared with the control group, the plant height increment, ground diameter increment, biomass, and root volume, the leaf number, leaf area, and chlorophyll content of poinsettia were inhibited to varying degrees, but no obvious symptoms of heavy metal toxicity were observed.（ⅱ） Poinsettia had strong resistance to Zn, which was shown in that TI was more than 50%, which showed a certain ‘hormesis’ phenomenon with the increase of Zn concentration in soil; The MDA content increased under high Zn concentration; The change of relative conductivity of leaves was not significant.（ⅲ） The Zn content in different parts of the poinsettia plant was positively correlated with Zn concentration in soil, and the accumulation capacity of different tissues for Zn was roots ＞ leaves ＞ stems.Under all treatments, the Zn content in the aboveground parts of poinsettia was significantly higher than that in the roots.Except for the T1 treatment（0.96）, the TF of the other treatments was ＞ 1, which was suitable for phytoextraction.【Conclusion】Poinsettia has a certain tolerance to Zn.When Zn concentration in soil is 1000 mg/kg, the accumulation and migration（from roots to the aboveground parts） ability of poinsettia for Zn are strong, which makes poinsettia suitable for phytoextraction.As an ornamental plant, poinsettia can also beautify the environment while phytoremediation is carried out in heavy-metals contaminated areas.

[目的]研究氮、磷、钾肥的配比施用对山苍子果实精油含量及其主要成分的影响情况,为山苍子的科学施肥提供参考依据和技术指导.[方法]以 4 年生的同一家系山苍子实生苗为试验材料,分别以氮(N)、磷(P)、钾(K)肥为试验因素,设计3个因素5个水平共25个施肥处理的L25(35)正交试验方案进行施肥试验,以不施肥的处理(T1)为对照.施用的肥料分别为尿素、过磷酸钙、碳酸钾,其有效成分及其含量分别为N(46%)、P2O5(18%)、K2O(68%).分别于 2018 年的春季(3 月下旬)与秋季(10 月下旬)采用沟施法施肥,共施肥 2 次.采用水蒸气蒸馏法提取果实精油,计算精油得率,并采用气质联用色谱(GC-MS)法和峰面积归一法对精油的主要成分进行定量分析.[结果]T4(N1P4K4)处理的精油得率(3.53%)最高,为对照组的5.31 倍,T3(N1P3K3)和T5(N1P5K5)处理的精油得率次之,均大于 3%;3 种肥料对山苍子果实精油得率的影响程度由大到小依次为P＞N＞K,其中最优施肥处理组合为N1P4K5.25 个处理的山苍子果实精油中共同含有的成分有 9 种,分别为香叶醛、橙花醛、1-庚醇、柠檬烯、十一烷、芳樟醇、十二烷、辛酸甲酯、香叶醇,其峰面积之和占相应处理的山苍子果实精油中含有的所有成分总峰面积的 67%以上;各处理山苍子果实精油中较为罕见的特有成分有 8 种,其中对照处理的氯甲酸正辛酯及T19(N4P4K2)、T21(N5P1K5)处理的 1-己醇的含量均较高.精油中各个成分含量间的相关性分析结果表明,柠檬醛与十一烷、芳樟醇、十二烷和辛酸甲酯之间均呈显著正相关(P＜0.05).25 个处理的山苍子果实精油中的柠檬醛含量均在 48%以上,T16(N4P1K4)处理的柠檬醛含量(63.310%)最高,其次为T13(N3P3K5)、T9(N2P4K5)处理的,其柠檬醛含量均大于 60%.[结论]施肥能显著提高山苍子果实精油得率,果实精油得率最高的施肥处理为T4(N1P4K4);果实精油中柠檬醛含量最高的施肥处理是T16(N4P1K4).生产中应根据山苍子的栽培目的有针对性地配比施肥,从而提高定向栽培的山苍子资源利用率.

【目的】改良传统农业生产预测方法，实现油茶产量的快速高效预测，为油茶实际生产提供参考。【方法】收集油茶栽种较为集中的湖南、江西、浙江、广西的油茶籽年度总产量、实有油茶林面积、气象等数据，选择17个气象指标作为油茶产量的影响因素，使用MATLAB软件，通过主成分分析提取出主成分，再将主成分作为BP神经网络的输入集，在传统神经网络模型基础上构建主成分分析与BP神经网络组合模型，对4个地区油茶籽单位面积年产量进行预测。BP神经网络的训练集和测试集选用1990—2018年的数据，采用2019年的数据对模型预测效果进行验证，最后应用模型对2025年油茶籽单位面积产量进行预测。【结果】对主成分有重要贡献的气象因子有日照时长、6—11月气温、3—5月降水量、平均最低气温、露点温度、平均风速、最大持续风速以及海平面气压。改进后模型迭代耗时更少，拟合度较高，对4个地区油茶产量的预测结果的平均相对误差均低于3%。应用模型预测得到2025年湖南、江西、浙江、广西的单位面积油茶干籽产量分别为0.831、0.583、0.449、0.512 t/hm~2。【结论】与传统预测模型相比，改进后的主成分分析与BP神经网络组合模型的预测效率和预测精度均有提高，在今后一段时期内4个地区的油茶产量有较好的发展趋势。

[目的]研究不同间作模式对山苍子光合特性及其栽培土壤水分和养分的影响情况,为筛选出较好的山苍子间作模式提供理论依据和生产指导.[方法]以同一家系的6年生山苍子植株为试验材料,采用顺序排列试验设计方法,共设计6个间作处理,分别为清耕、山苍子间作白车轴草、山苍子间作红车轴草、山苍子间作高羊茅、山苍子间作百日草、山苍子间作万寿菊,并对不同间作模式下山苍子的光合参数、栽培土壤中水分和养分含量进行测定分析.[结果]间作高羊茅和间作百日草均能缓解山苍子的"午休"现象,均能促进山苍子的生长发育,这两种间作处理的山苍子其净光合速率日均值分别为5.18与4.89μmol?m-2?s-1;间作白车轴草和间作高羊茅的山苍子其气孔限制值均在16:00时达到了最高值,分别为64％与77％,且其叶片的平均光能利用率分别达到0.57％与0.61％;间作万寿菊和间作高羊茅均能较为显著地提高山苍子叶片的水分利用效率及其栽培土壤的水分含量,其水分利用效率平均值较清耕处理山苍子的平均值分别高出26％与32％,因其用于光合作用的有效水分较多,故其抗旱能力均强于其他处理的;间作万寿菊的山苍子其栽培土壤的水分含量最高,且与清耕处理的相比,其水分含量高出16.15％;间作万寿菊和间作高羊茅均可有效增强山苍子适应强光的能力而降低叶温.间作百日草、间作万寿菊和间作高羊茅均可显著地提高其栽培土壤中的全氮含量,间作白车轴草的土壤全钾和速效磷含量均高于清耕处理的,间作红车轴草可以显著地提高其栽培土壤中有机质和铵态氮的含量,间作红车轴草和间作高羊毛均可有效提高其栽培土壤中速效磷与速效钾的含量.[结论]间作红车轴草和间作高羊茅均可有效增强山苍子适应强光环境的能力,均有利于山苍子营养物质的积累,促进山苍子的生长发育,提高其经济效益;间作高羊茅和间作万寿菊均能增强山苍子的抗旱能力;间作万寿菊、间作百日草、间作高羊茅和间作红车轴草均可较为显著地提高山苍子栽培土壤的养分含量.

森林生态食品是近年来提出的新型森林生态标志产品,是继农产品"三品一标"与森林食品之后,融合了天然、绿色、安全、营养、健康等生态元素的新型食品标准.本文对森林生态食品的出现、发展及认定进行了综述,并提出了相应的发展策略.

Abstract Rosemary (Rosmarinus officinales L. (Labiatae)) is one of the major economic crops in the world, and rosemary essential oil (REO) is one of the top products derived from rosemary and has excellent commercial prospects. Many factors affect the yield of REO extracted by hydrodistillation (HY). This study was proposed to identify and analyze these factors to maximize the yield of essential oils and reduce the cost. First, two different single‐factor extraction experiments were conducted, (1) adding NaCl and (2) using various organs of the plant, to determine the influence of each factor on the oil yield. Based on single‐factor experiments, the orthogonal experiments (L9, 33) were designed to determine the optimal conditions for the extraction of rosemary oil. Meanwhile, the kinetic extraction analysis of the test data was carried out. The results revealed that the highest oil yield was achieved when rosemary leaves were crushed to 2 cm, the ratio of water to the material was 1:3, and NaCl concentration was 5%. A simple first‐order kinetic model has also proved to be an acceptable general choice and allows to predict the output of extraction operations overtime accurately and robustly in practice. This study provides a reference scheme for using hydrodistillation to extract rosemary essential oil.

Potentially toxic elements (PTEs) pollution has become a serious environmental threat, particularly in developing countries such as China. In response, there is a growing interest in phytoremediation studies to identify plant species as designated hyperaccumulators of PTEs in polluted soils. Poinsettia was selected as a candidate species for phytoremediation of six PTEs (Zn, Pb, Hg, Cr, As, Cu) in this study. A pot cultivation experiment (randomized incomplete block experimental design with 5 treatments and 4 blocks) was conducted using contaminated soils gathered from an industrial area in southcentral China. The bioaccumulation factor (BAF), translocation factor (TF), and bioconcentration factor were analyzed to determine the phytoremediation potential of poinsettia potted in different ratios of polluted soils. One-way ANOVA with post-hoc Tukey's test showed that poinsettia had significant uptake of Zn, Pb, Cu (BAF < 1 and TF < 1, p < 0.05) and Hg (BAF < 1 and TF > 1, p < 0.05). Poinsettias can therefore effectively accumulate Zn, Pb, and Cu in their lateral roots while extracting and transferring Hg into their leaves. Moreover, poinsettia exhibited tolerance towards As and Cr. Interestingly, it was also observed that PTEs can inhibit the height of potted poinsettia at a certain concentration.

[目的]山苍子Litsea cubeba是我国特有的木本香料树种,其用途广泛,经济价值较高.本试验通过研究不同基质配方对山苍子容器苗生长的影响,筛选出山苍子最适宜的栽培基质,为山苍子容器育苗提供理论和参考依据.[方法]以山苍子1年生苗为试验材料,以泥炭、珍珠岩、锯末、黄心土为基质原料,采用单形重心混料试验设计方法,共设计9种基质配方,通过对不同基质配比下山苍子容器苗的物理性质、生长指标、叶片生物量、根系形态指标的测定分析,揭示不同基质配比对山苍子生长的影响.[结果]9种不同基质配方的物理性质存在显著性差异.其中T3处理下土壤密度最大,为0.73 g/cm3,T2处理下土壤密度最小,为0.54 g/cm3,两者之间存在显著性差异.土壤含水率最高达到37.36％.总孔隙度最大的为T2(61.56),最小的为T1(48.70),两者之间差异性显著.CK的pH值最小(5.08);不同基质配比对山苍子容器苗的苗高差异不显著.CK的地径(0.52 cm)是T2、T3和T8的2.08倍,显著高于这3个处理;高径比最小值为CK(66.97);不同基质配比对山苍子容器苗的叶片数量差异不显著,而不同基质配比对山苍子容器苗的叶片面积、叶片鲜质量、叶片干质量、叶片含水量差异达显著性水平;9种不同基质配方的根系形态指标也存在显著性差异.其中T8的主根长最大(12.6 cm),T1的主根长最小(5.8 cm),两者差异显著.[结论]通过主成分分析进行综合评定,结果表明:处理T2即V(黄心土):V(锯末):V(泥炭土):V(珍珠岩)=0.6:0.4:0:0为山苍子容器苗最佳基质配方.

Litsea cubeba is an important aromatic oil plant. Litsea cubeba pericarp essential oil has various physiological activities such as antibacterial activity, antioxidant capacity, etc., and is widely used. Its main ingredient is citral, which is the raw material for the synthesis of many precious spices. For the purpose of increasing yield, researchers have conducted many studies on the extraction of essential oil from pericarp of Litsea cubeba . But the extraction process still has room for optimization。In this study, Litsea cubeba fruits were subjected to an optimized method of hydrodistillation to increase the yield and biological activity of pericarp essential oils. Three-factor and three-level orthogonal experimental design was performed (fruit preservation time, distillation voltage and fruit microwave pretreatment time) to optimize the process. According to the results of orthogonal experiments, the highest yield of essential oil can be obtained after the fruit has been preserved for 9 days without microwave pretreatment and the distillation voltage is 220 V. The extracted essential oils were analyzed by gas chromatography-mass spectrometry (GC–MS), which indicated that their main components were 2,6-Octadienal, 3,7-dimethyl-, (E)-, 2,6-Octadienal, 3,7-dimethyl-, (Z)-, 1-Heptanol and 1-Octanol. GC–MS results showed that the relative content of citral in the extracted essential oil was the highest after the fruit was preserved for nine days without microwave pretreatment and the distillation voltage was 150 V. Changes in the process will not significantly affect the main component types of essential oils, but will significantly affect the relative content of the same components.

随着全球经济一体化进程的推进,中外联合办学模式日益成熟,为我国高校本科教育扬长避短、吸取国外成熟教学经验创造了良好的契机.作为国际上较先进的教学方法,行动教学法在我国高校本科教育课程教学中的应用尚存在较多空白,有待加强和推进.为此,中南林业科技大学班戈学院林学专业在引进“Environmental Data and Analysis”专业主干课程的同时,在课程教学中连续开展了为期2个学年的行动教学法的实践探索.首先,以行动教学法的基本理论为指导,对“Environmental Data and Analysis”专业课程的教学目标、教学大纲和内容、教学方法和手段、考核方式等进行了科学设计,强调课程教学以学生为中心、以学生为主体,教师教学与学生自主学习和探索相结合;注重学生的过程化培养和管理,降低期末考试在课程教学评价中的比重.其次,分课前、课中、课后等3个环节落实行动教学法在专业课程教学中的组织实施,指导学生在课堂讲授前预习知识要点,使学生带着问题走进课堂;采取以讨论为主的多种讲授形式开展课堂教学,培养学生自主学习的意识和能力以及团队协作精神;合理安排课后作业,引导学生在课堂讲授后自主反思重要知识点.最后,为了完善行动教学法的实施并推动其在大学本科教育课程教学中的广泛应用,对“Environmental Data and Analysis”专业课程实施行动教学法的效果进行了调查分析.效果评价结果显示,行动教学法的实施在一定程度上有效地突破了我国本科教育长期以来形成的“满堂灌、学生被动学习”的课程教学局限,加强了大学生自主思考习惯、主动学习能力和团队合作精神的培养.但是也发现,男女生在应对行动教学法的能力和素质上存在差异、各有长短;能否创造性地提出科学问题可能与是否具有团队合作意识和团队合作精神具有一定的相关性,二者之间存在相辅相成、协同促进的关系;提出科学问题能力的培养与理论与实践相结合、过程培养具有一定关联.因此,需要加强具有针对性的研究,并在行动教学法实际操作中采取相应措施.

利用人工蜂巢收集白斑切叶蜂（Megachile strupigera）蜂粮样本,并通过克隆测序方法,比较分析了新余市水北镇（XYSB）、吉安市戈坪乡（JAGP）、赣州市沙地镇（GZSD）和赣州市齐云山自然保护区（GZQYS）的4种不同林地类型的白斑切叶蜂粉源植物组成及多样性。共鉴定出粉源植物9科10属15种。其中黄荆Vitex negundo和山牡荆Vitex quinata为优势种。Chao1指数、Shannon-wiener指数和Simpson指数分析结果表明,4个样地粉源植物的丰富度和多样性依次为GZQYS＞GZSD＞XYSB＞JAGP。并且,4个样地七月上旬的物种丰富度均明显高于八月中旬。同一时期的粉源植物种类及多样性存在显著差异,表明不同林地利用方式对白斑切叶蜂粉源植物多样性的影响非常明显,并随人为干扰程度的增高而降低。相同样地中2个不同时期均呈现出粉源植物多样性随花期变化而降低的趋势,但其主要粉源植物种类没有发生改变,表明该蜂主要粉源植物没有受到花期变化的影响。因此,黄荆和山牡荆是白斑切叶蜂的主要粉源植物,对维持白斑切叶蜂种群的稳定具有重要作用。

Andrena is a large bee genus of >1500 species, which includes many important pollinators of agricultural systems. In this study, we present three mitochondrial genomes (mitogenomes) of Andrena species, which are the pollinators of Camellia oleifera. Compared with putative ancestral gene arrangement of insects, the three mitogenomes present identical gene rearrangement events, including local inversion (trnR) and gene shuffling (trnQ/trnM, trnK/trnD, and trnW/trnC-trnY). Most PCGs initiate with standard ATN codon and share the stop codon of TAA or TAG, whereas truncated stop codon T was detected in the atp6 gene of A. chekiangensis. Furthermore, the nad4 gene end with a single T in all three Andrena species. All tRNAs could be folded into clover-leaf secondary structure except for trnS1, with the dihydrouracil (DHU) arm forming a simple loop. Phylogenetic analysis is performed on 17 Andrena mitogenomes. Maximum likelihood and Bayesian methods generate identical topology, in which A. hunanensis and A. striata form a group and are close to A. camellia. Although A. chekiangensis is also difficult to be distinguished from A. camellia by morphological methods, A. chekiangensis and A. haemorrhoa form a clade and are grouped with the other taxa of the genus Andrena.

以新型聚酰胺复合正渗透膜的2种膜方位[膜的活性层朝向原料液(即AL-FS模式)和膜的活性层朝向汲取液(即AL-DS模式)]对5种不同的重金属原料液进行处理.结果表明,在AL-DS模式下各处理的正向水通量都高于在AL-FS模式下的,且同一重金属原液在2种模式下水通量差异极显著(P<0.01).反向盐通量表现为AL-DS模式高于AL-FS模式,但只有砷、汞的反向盐通量在2种模式下差异显著(P<0.05).对于同一重金属原液,Js/Jw值表现为AL-DS模式均低于AL-FS模式,且2种模式下的Js/Jw值都低于0.02.2种模式下对汞的拦截效果都很好,拦截率分别达到99.50％(AL-DS模式)、90.66％(AL-FS模式),其中以铅、砷、汞为原液时,重金属拦截率表现为AL-DS模式高于AL-FS模式,以镉、铬为原液时结果相反.

以观音莲(Herba monachosori Henryi)、姬星美人(Sedum das yph yllum)、奥普琳娜(Graptoveria‘Opalina’)、白美人(Pachyphytum ovifrum)和虹之玉(Sedum rubrotinctum)5种景天科多肉植物3年生扦插苗为试材,以人工低温胁迫的方法,通过对胁迫后植物叶片可溶性糖含量、叶片相对含水量、脯氨酸含量、丙二醛含量、恢复生长后植物成活率的测定,研究了低温对5种多肉植物的生理影响,以期为筛选耐低温多肉植物品种提供参考依据.结果表明:随着低温胁迫的加剧,5种多肉植物体内脯氨酸含量、叶片相对含水量、可溶性糖含量、丙二醛含量在总体上均呈上升趋势,但增幅略有不同.奥普琳娜的叶片相对含水量和丙二醛含量变化最为明显,观音莲最不明显.在低温胁迫后,5种多肉植物中,观音莲的有机溶质脯氨酸和可溶性糖含量最高,奥普琳娜最低.综合分析得出5种多肉植物的耐寒性从强到弱依次为观音莲＞姬星美人＞虹之玉＞白美人＞奥普琳娜.

Sedum rubrotinctum is widely grown as an ornamental because of its attractive leaf shape and color. Increasing the morphological diversity and color will greatly add to its ornamental value. Environmental conditions such as light and temperature can change the leaf color of succulent plants, but the mechanism is uncertain. To examine this mechanism, we tested the effects of two commercial chemical products Sowing Goodliness (Sg) and Aromatic Garden (Ag) on the morphology, pigment content, and growth performance of Sedum rubrotinctum seedlings. The Sg treatment did not change foliage color, but can accelerate plant growth and increase lateral bud number. The Ag treatment had marked changes on the relative proportions of pigments and leaf color, and plant growth was severely reduced with mortality observed in some plants. After Ag stress was discontinued, the surviving plants began to regrow and had good ornamental value but had the fewest number of lateral buds and leaves, and the smallest leaf length and thickness, canopy diameter, and plant height. Foliage color changes are caused directly by shifts in the relative proportions of pigments, particularly chlorophyll b and anthocyanin. In Ag-treated plants, chlorophyll b declined much faster than chlorophyll a, indicating that the transformation of chlorophyll b into chlorophyll a is an important step in the chlorophyll degradation pathway. Ag provides a way to learn more about the mechanism of chlorophyll degradation and should be investigated further. Ag enhanced anthocyanin production rapidly and improved the ornamental value of Sedum rubrotinctum. Different concentrations of Ag and Sg were not studied in this trial and might be tested to determine the ideal balance between leaf color and plant growth.

开展湖南省不同山苍子种质资源果皮精油成分分析与评价,对于筛选与培育优良精油用山苍子优良单株与品种具有重要意义.实验对湖南省6个山苍子天然居群果皮精油进行提取,采用气质联用色谱法(GC-MS)分析其精油成分,并用峰面积归一法对主要成分进行定量分析.结果 表明,不同居群果皮含油率存在差异,株洲白马乡含油率最高(3.35％),且变异系数最小(4.78％);6个居群的山苍子果实精油GC-MS成分各鉴定出27种、20种、21种、19种、19种、23种,分别占总峰面积的99.73％、99.81％、99.80％、99.82％、99.81％、99.73％;所有居群共有成分为9种,各居群分别鉴定出各自独有成分;D-柠檬烯含量为不同山苍子居群果皮精油含量分类的依据,在衡阳市衡阳县、衡阳常宁市、郴州桂东县、岳阳平江县、株洲白马乡这5个居群间进行山苍子D-柠檬烯型优良单株或品种选育的潜力较大.因此,在精油用山苍子选育及种质资源评价方面,要综合考虑不同生态型遗传因素的影响.

Poinsettia (Euphorbia pulcherrima, Wind. ex Klotzsch) originated in Mexico is an important ornamental tree in all over the world because its bract color can change from green to red under short-day conditions. In view of this, poinsettia not only has high ornamental value but also is an important model plant in studies on anthocyanin metabolism regulated by photoperiod. In this research, we compared the content of metabolic products in anthocyanin biosynthesis pathway and transcriptome sequencing data between green and red-turning bracts of poinsettia to clarify the mechanism of color change. The results of metabolic product analysis suggested that far downstream genes such as dihydroflavonol 4-reductase (DFR) gene in anthocyanin biosynthesis pathway could be inhibited in green bracts. A total of 91,917 uni-transcripts were identified through transcriptome sequencing. Seventy-two uni-transcripts were assigned to flavonoid biosynthesis pathways. Through a correlation analysis of gene expression profiles and color compound contents, DFR was taken into account as a candidate gene promoting anthocyanin accumulation in poinsettia bracts under short-day conditions. Transgenic research showed that overexpression of poinsettia DFR significantly increased the anthocyanin content in Arabidopsis (Arabidopsis thaliana). Based on these results, this research identified DFR as a promoter of anthocyanin accumulation in poinsettia bracts under short-day conditions. Moreover, the results of this research will shed light on elucidation of anthocyanin biosynthesis mechanism of plants and provide candidate genes for genetic improvement on poinsettia.