玫瑰花的微波真空干燥试验

为了提高玫瑰干花品质,减少干燥时间。该研究通过试验性微波真空干燥设备对玫瑰花进行干燥,比较了不同真空度和微波功率对玫瑰干花品质的影响。研究结果表明,真空度越高,物料内水分蒸腾而干燥的速度越快,物料温升越低。随着微波功率增加,干燥时间大大缩短。综合考虑玫瑰干花干燥时间、温度、形态变化和颜色等指标,并与热风干燥相比,选择真空度0.10 MPa,微波功率200 W,干燥时间80 min的微波真空干燥工艺为较适宜的干燥条件,研究结果为玫瑰花的干燥和工业化生产提供一定的理论依据。     

玫瑰花的微波真空干燥试验研究

通过实验性微波真空干燥设备对玫瑰花进行干燥,比较了不同真空度和微波功率对玫瑰干花品质的影响。研究结果表明,真空度越高,物料体内水分蒸腾而干燥的速度越快,物料温升越低。随着微波功率增加,干燥时间大大缩短。综合考虑玫瑰干花形态变化,颜色和干燥时间和温度等指标,并与热风干燥相比,选择真空度0.1MPa,微波功率200W,干燥时间80min的微波真空干燥工艺为最适宜的干燥条件,研究结果将为玫瑰花的干燥和工业化生产提供一定的理论依据。     

腊梅高山生态葡萄

腊梅葡萄园位于南川区南平镇神龙峡景区,海拔800多米,四面高山耸立。昼夜温差大,光照好,土壤肥沃,水是山泉水,水质纯净。可直接饮用,是种植生态、绿色、优质葡萄的好地方。腊梅葡萄园总规划500亩,集葡萄种植、休闲旅游、观光为一体,有巨玫瑰、巨丰、醉金香、夏黑、摩尔多瓦、甜蜜香等10余个葡萄品种,葡萄果粒颜色有紫黑色、墨黑色、淡红色、绿色、黄绿色等;口感有玫瑰花香味、红富士苹果味、蜂蜜味、奶     

花朵硕大的切花新秀——姜荷花

姜荷花（Curcuma alsimatifolia）是近年引进的切花新品种，因其具有温婉如莲的花姿、长达15天的瓶插寿命、用来插花后的水清澈无异味等优点而深受切花市场欢迎。姜荷花为姜科姜黄属植物，原产于泰国清迈一带，也是中国古代常见的药草植物（药名郁金），而姜荷花这个名称是在台湾开始栽培时命名的，因其属于姜科且具有荷花的美姿，故有此名。除切花应用外，也适于园林绿化、盆栽观赏。     

盆栽荷花十八字诀

荷花古生华夏，秉性高洁，风姿潇洒。上溯至三千年以前，《诗经》中就有“彼泽之彼有蒲与荷”的诗句。荷花“出污泥而不染”的节操，更是砥砺着无数志士的品行，拒腐蚀而廉洁白重。荷花的盆栽观赏自晋代已有记载，明清更是兴旺，盆栽荷花已发展到一百多个品种。盆栽荷花需掌握好18字诀技术环节。     

家庭保健花卉栽培与应用 上卷 草本植物

百里香（Thymus spp．）为唇形花科百里香属草本植物，多年生呈亚灌木状。原产地中海沿岸，风行于欧美地区。我国已有引进栽培种植。喜凉爽气候，比较耐寒。多分枝，匍匐或斜向上生长；叶小，椭圆形，数量多；春季开花，花朵小，淡紫色；小坚果近圆形、光滑。常见栽培的品种有宽叶百里香、柠檬百里香、浓香百里香、铺地百里香等。     

可食性葡甘聚糖复合抑菌膜及其应用研究

以研究可食性复合抑菌膜为目的，以多糖为基材，用增塑剂、补强剂、脂质、乳化剂和天然防腐剂作为辅料，研究了干燥温度、时间和不同的辅料等因素对可食性复合抑菌膜的物理和机械性能的影响，并进行了抑菌试验。结果表明：以魔芋葡甘聚糖为主料，在30～40℃条件下烘干1 h，可得到具有一定强度，阻湿阻气性良好的可食性复合抑菌膜，同时将其应用于食用菌和柑桔类等果蔬保鲜上。食用菌用复合抑菌膜保鲜贮藏4 d后失重率和褐变度分别为5.5%和0.11，柑桔类水果贮藏2周后腐烂率低于2%，保鲜效果明显优于对照，葡甘聚糖可用来制作可食性抑菌膜。     

家庭保健花卉栽培与应用 上卷 草本植物连

<正>【连载三:旱金莲】旱金莲(Tropaeolummajus)又名金莲花、旱荷花、旱莲花、旱莲、菏叶莲、荷叶花。原产于南美洲秘鲁、智利等地,为金莲花科金莲花属多年生蔓性草本植物。叶互生,具长柄,圆形或近肾形盾状,边缘有波状钝角,叶形如碗莲;花单生叶腋,花有红、黄、橘黄等色,多单瓣,也有重瓣、半重瓣。花期2—5月。     

笼养海南鳽的食性研究

2001年7月至2002年5月，在对海南鳽救护的基础上，研究了笼养海南鳽的觅食活动及其食性。经过13次的觅食活动和9次食性选择的观察．得到如下结果：笼养海南鳽以晨昏活动为主，白天休息。日觅食活动呈现早7：00～9：00和晚19：00～21：00两个高峰。日觅食时间在春、夏、冬三季的差异不显著。笼养海南鳽以动物性食物为食，不食植物性食物。在吞食的几种动物性食物中，鱼类占的比例最大。各食物所占的比例是：长圆形鱼53．66％，纺缍形鱼36．58％，虾4．07％，蛙类2．44％．蝗虫3．25％．表明笼养海南鳽对食物选择性高．食物格局狭窄．为狭食性动物。对食物长度与取食频次进行的分析表明两者间不相关，说明食物长度不影响海南鳽选择食物。X^2检验表明海南鳽在夏、冬季的食性存在差异，其差异是对不同形态的鱼的偏好引起的。     

浅析绿茶的品饮价值与保健功能

从色、香、味、形等方面分析绿茶的品饮价值,重点介绍维生素C、儿茶素、茶氨酸和咖啡碱等成分的保健功能.     

低氮和干旱胁迫对富士和秦冠生长及氮素利用的影响

【目的】以富士（Fuji）、 秦冠（Qinguan）嫁接在平邑甜茶（Malus hupehensis Rehd.）上的当年生盆栽苗为试验材料,采用砂培方法,研究了缺氮胁迫和干旱对富士和秦冠生长情况、 光合参数、 植株各部位氮磷钾含量及氮素利用效率的影响,分析比较了低氮干旱条件下富士和秦冠生长及氮素利用的差异,以期为果树生产高效肥水利用提供理论指导。【方法】试验共设四个处理: 正常氮正常水（ZZ）、 低氮正常水（DZ）、 正常氮干旱（ZG）、 低氮干旱（DG）。氮素和水分均设置两个水平,分别为正常氮（6 mmol/L NO-3-N）、 低氮（0.3 mmol/LNO-3-N）、 正常供水（保持盆中砂子相对含水量为饱和含水量的80%~85%）、 干旱处理（保持盆中砂子相对含水量为饱和含水量的60%~65%）。【结果】富士和秦冠的生物量（茎和叶）、 株高茎粗等生长指标以及光合速率、 气孔导度、 蒸腾速率均为正常氮正常水（ZZ）＞低氮正常水（DZ）＞正常氮干旱（ZG）＞低氮干旱（DG）,并且相对应处理下秦冠的以上指标均高于富士;正常供水下,缺氮处理使富士、 秦冠的根冠比比正常氮处理均有所增加,富士提高了2.05%,秦冠提高了22.40%。富士和秦冠的氮、 磷、 钾含量均表现出正常氮正常水（ZZ）＞低氮正常水（DZ）＞正常氮干旱（ZG）＞低氮干旱（DG）; 氮、 钾元素含量在植株各部位的分布顺序依次是叶＞根＞茎,磷元素则是根＞叶＞茎;光合氮素利用效率（PNUE）和氮素利用效率表现为秦冠处理之间差异极显著,富士处理之间差异不显著;秦冠的PNUE和NUE明显高于富士,在低氮正常水（DZ）处理下,秦冠氮肥利用率比富士高42.07%,在低氮干旱（DG）处理下高64.14%;低氮胁迫下富士和秦冠的NUE显著提高,并且秦冠提高的幅度高于富士。【结论】施用氮肥能够显著提高富士与秦冠的干物质量,同等水肥条件下,秦冠生长优于富士;水分亏缺会减少叶片对氮的吸收,干旱条件下适度增施氮肥,可提高果树的抗旱能力;低氮干旱胁迫下秦冠的生长指标、 光合指标及氮素利用效率指标均优于富士,表现出较强的抗低氮干旱胁迫的能力。     

Pasture Vegetation Elemental Analysis by Laser-Induced Breakdown Spectroscopy

Laser-induced breakdown spectroscopy (LIBS) is a new technique for the analysis of plant material. This study investigates the application of LIBS to pasture-based plant samples. The LIBS measurements were obtained from pelletized pasture samples (100 samples) that had been also analyzed by inductively coupled plasma–optical emission spectroscopy (ICP-OES) following microwave digestion for calibration and comparison purposes. Comparisons for elements sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), boron (B), phosphorus (P), and sulfur (S) showed that LIBS could be used for almost all the standard profile total elements with concentrations down to low mg/kg levels (observed error of Na: 0.024 percent, K: 0.18 percent, Mg: 0.016 percent, Ca: 0.073 percent, P: 0.017 percent, Mn: 31 mg/kg, Fe: 150 mg/kg, Zn: 6.6 mg/kg, and B: 1.1 mg/kg). Elemental analysis at less than mg/kg levels was not possible using LIBS. The elements S and Cu were particularly difficult to analyze with reliability using LIBS at the concentration levels found in the plant samples. Replacing microwave digestion and subsequent ICP analysis with a direct analysis of dried plant samples using LIBS has the potential to improve the productivity and reduce the cost of testing.     

Faculty positions:Center for Agricultural Resources Research,Chinese Academy of Sciences

正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology,     

Macroinvertebrates in North American tallgrass prairie soils: effects of fire, mowing, and fertilization on density and biomass

The responses of tallgrass prairie plant communities and ecosystem processes to fire and grazing are well characterized. However, responses of invertebrate consumer groups, and particularly soil-dwelling organisms, to these disturbances are not well known. At Konza Prairie Biological Station, we sampled soil macroinvertebrates in 1994 and 1999 as part of a long-term experiment designed to examine the effects and interactions of annual fire, mowing, and fertilization (N and P) on prairie soil communities and processes. For nearly all taxa, in both years, responses were characterized by significant treatment interactions, but some general patterns were evident. Introduced European earthworms (Aporrectodea spp. and Octolasion spp.) were most abundant in plots where fire was excluded, and the proportion of the total earthworm community consisting of introduced earthworms was greater in unburned, unmowed, and fertilized plots. Nymphs of two Cicada genera were collected (Cicadetta spp. and Tibicen spp.). Cicadetta nymphs were more abundant in burned plots, but mowing reduced their abundance. Tibicen nymphs were collected almost exclusively from unburned plots. Treatment effects on herbivorous beetle larvae (Scarabaeidae, Elateridae, and Curculionidae) were variable, but nutrient additions (N or P) usually resulted in greater densities, whereas mowing usually resulted in lower densities. Our results suggest that departures from historical disturbance regimes (i.e. frequent fire and grazing) may render soils more susceptible to increased numbers of European earthworms, and that interactions between fire, aboveground biomass removal, and vegetation responses affect the structure and composition of invertebrate communities in tallgrass prairie soils.     

Variation in quality parameters between and within 14 Nordic tree fruit and berry species

Abstract

A 3-year study was carried out to investigate quality parameters in 14 tree fruit and berry species grown in southern Norway. The species were blueberry, apple, aronia, sour cherry, sweet cherry, red raspberry, strawberry, blackcurrant, gooseberry, red currant and elderberry, harvested along with wild bilberry, cloudberry and lingonberry. Significant differences between species were identified for all quality parameters. The coefficient of variation between species was lowest for pH (12.5%), dry matter (18.9%) and soluble solids (25.3%), followed by titratable acids (59.3%), total phenolics (83.8%), antioxidant capacity FRAP (85.7%) and antiradical power by the DPPH-assay (97.8%), total monomeric anthocyanins (132%) and ascorbic acid (137%). Average coefficient of variation within species were lower and ranged from 4 (pH) to 62% (ascorbic acid). Only the FRAP values were significantly affected by harvesting year with lower levels in 2004 than in 2005 and 2006. There were significant interactions between species and harvesting year for dry matter, soluble solids, pH, ascorbic acid and FRAP. The results indicate generic ranges in composition within species independent upon growing location and climate, and the composition of the tree fruits and berries is not likely to deviate from these ranges. It is concluded that desirable composition of tree fruits and berries and their products should primarily be achieved by selection among species rather than searching fors broadened variation within individual species.     

Potassium Fixation and Release Characteristics in Rhizosphere and Nonrhizosphere Soils for a Rapeseed–Rice Cropping Sequence

Potassium (K) fixation and release in soil are important factors in the long-term sustainability of a cropping system. Changes in K concentration and characteristics of K fixation and release in rhizosphere and nonrhizosphere soils in the rapeseed (Brassica napus L.)–rice (Oryza sativa L.) rotation were investigated using a rhizobox system. The concentrations of different forms of K in both rhizosphere and nonrhizosphere soils decreased with plants compared to without plants, regardless of K fertilizer application. Potassium uptake by crops mainly came from the rhizosphere soil. In the treatment without K fertilizer (–K), the main form of K supplied by the soil to the crops was 1.0 mol L^?1 nitric acid (HNO₃) nonextractable K, followed by nonexchangeable K, and then exchangeable K. In the treatment with K fertilizer (+K), the main K forms supplied by the soil to the crops were exchangeable K and nonexchangeable K. The amount and rate of K fixation after one cycle of the rapeseed–rice rotation was greater in rhizosphere soil than in nonrhizosphere soil. The amount and rate of K fixation of soil in the +K treatment were significantly less than in the –K treatment. The cumulative amounts of K released with 1.0 mol L^?1 ammonium acetate (NH₄OAc) and 1.0 mol L^?1 HNO₃ extraction increased with the increasing numbers of extractions, but the K-releasing power of soil by successive extraction decreased gradually and finally became almost constant. The release of K was less in rhizosphere soil than in nonrhizosphere soil. The release of K in the +K treatment was similar to that in the –K treatment in rhizosphere soil, but the K release in nonrhizosphere soil was greater with the +K than the –K treatment. Overall, the information obtained in this study will be helpful in formulating more precise K fertilizer recommendations for certain soils.     

Electron donor and pH relationships for biologically enhanced dissolution of chlorinated solvent DNAPL in groundwater

Biologically enhanced dissolution offers a method to speed removal of chlorinated solvent dense non-aqueous-phase liquid (DNAPL) sources such as tetrachloroethene (PCE) and trichoroethene (TCE) from aquifers. Bioremediation is accomplished by adding an electron donor to the source zone where fermentation to intermediates leading to acetic acid and hydrogen results. The hydrogen and possibly acetic acid are used by dehalogenating bacteria to convert PCE and TCE to ethene and hydrochloric acid. Reductive dehalogenation is thus an acid forming process, and sufficient alkalinity must be present to maintain a near neutral pH. The bicarbonate alkalinity required to maintain pH above 6.5 is a function of the electron donor: 800 mg/L of bicarbonate alkalinity is sufficient to achieve about 1.2 mM TCE dechlorination with glucose, 1.7 mM with lactate, and a much higher 3.3 mM with formate. Laboratory studies indicate that in mixed culture, formate can be used as an electron donor for complete conversion to ethene, contrary to pure cultures studies indicating it cannot. Various strategies can be used to add electron donor to an aquifer for DNAPL dehalogenation while minimizing pH problems and excessive electron donor usage, including use of injection-extraction wells, dual recirculation wells, and nested injection-extraction wells.     

Biodiversity and ecogeography of wild Lactuca spp. in some European countries

Staff members of the Department of Botany of Palacký University in Olomouc and Gene Bank Department – Workplace Olomouc, Research Institute of Crop Production in Prague, Czech Republic, conducted an expedition in seven European countries (Austria, Czech Republic, France, Germany, Italy, the Netherlands, Switzerland) in August/September 1999 to collect wild Lactuca spp. germplasm and study its geographic distribution, ecology and biodiversity. During the mission, more than 600 locations were visited resulting in the collection of 602 seed samples (accessions) of wild Lactuca species and 13 seed samples of related genera (Chondrilla and Mycelis). Lactuca serriola f. serriola, L. serriola f. integrifolia, L. saligna and L. viminea subsp. chondrilliflora were prevalent in southern Europe (Italy, France), however, only L. serriola was common in central and western Europe (Austria, Czech Republic, Germany, Netherlands, Switzerland). The greatest diversity of Lactuca species was found in France, where also the most seed samples (165) were collected. The most characteristic habitats with a high density of Lactuca spp. populations were observed along roads and highways, grassy ditches, ruderal communities, and dust-heaps. Natural infections by powdery mildew (Erysiphe cichoracearum) and downy mildew (Bremia lactucae) on some wild Lactuca spp. were observed. Recent observations concerning the geographic distribution, population structure, habitats, and natural occurrence of diseases of Lactuca spp. are discussed. This assemblage of genetic resources of Lactuca spp. can serve as the basis of future studies of species diversification, spatial population structure, plant microevolution, domestication processes, and genetic variability of host-parasite interactions.     

Increase in auxiliary photoprotective photosynthetic pigments in wheat seedlings induced by Azospirillum brasilense

Inoculation of wheat seedlings with the plant growth-promoting bacterium Azospirillum brasilense Cd was immobilized in alginate microbeads and, without applying any stress, significantly increased the quantity of several photosynthetic pigments, such as chlorophyll a, chlorophyll b, and the auxiliary photoprotective pigments violaxanthin, zeaxanthin, antheroxanthin, lutein, neoxanthin, and β-carotene. This resulted in greener plants with no apparent visible stress. After monitoring the quantity of photosynthetic pigments for 4 weeks, we observed that inoculated plants had higher quantities of pigments in shoot and stem. The greatest difference in the quantity of all pigments between inoculated and noninoculated plants occurred in the first week of growth. Regardless of treatment, the quantity of pigments in stems was three to four times less than the quantity of these pigments in shoots. Application of Azospirillum, either as liquid inoculant or as alginate microbeads, did not alter the positive effect of the bacteria on pigment production or the positive response of the plants towards A. brasilense Cd inoculation.     

In-situ enrichment and analysis of atrazine-degrading microbial communities using atrazine-containing porous beads

We examined the community composition of microbes that colonized atrazine-containing beads buried in agricultural soils that differed in atrazine treatment history. Bacterial abundance was 5-40-fold greater in atrazine-fortified beads. In beads containing 20 mg atrazine kg⁻¹ buried in soil with a history of atrazine application (conditioned soil), the abundance of Actinobacteria increased approximately 80-fold whereas in control soil, Actinobacteria were enriched only 10-fold and the gamma-Proteobacteria and Planctomycetes increased by 60- and 25-fold, respectively. The gamma-Proteobacteria were enriched by 120- and 230-fold in beads containing 200 mg atrazine kg⁻¹ in conditioned and control soil, respectively. The results demonstrate that BioSep^® beads are a suitable matrix for recruiting a diverse subset of the bacterial community involved in atrazine degradation.