香茅草离体快繁体系的建立

以香茅草地下茎段为外植体,研究了不同基本培养基和植物生长调节剂组合对芽诱导、增殖和生根的影响.结果表明:适于香茅草芽诱导的培养基为WPM+6-BA 1.0 mg·L-1+NAA 0.1 mg·L-1,芽诱导率可达81.1％;适于芽增殖的培养基为WPM+6-BA 2.5 mg·L-1+NAA 0.4 mg·L-1,增殖倍...     

朝天罐的离体培养与植株再生

以朝天罐（Osbeckia opipara）的茎段为外植体进行离体培养植株再生研究,结果表明：茎段在适宜的培养基上可形成愈伤组织,并分化成再生植株。培养基MS + 6-BA 2 mg/L  + NAA 0.2 mg/L + 蔗糖30 mg/L+ 琼脂7 mg/L,既适合于愈伤组织的诱导,也适合于愈伤组织的增殖和分化,诱导率为83.3％;丛生芽增殖的最佳培养基为MS + 6-BA 0.2 mg/L+ NAA 0.1 mg•L-1 + 蔗糖 50 mg/L + 琼脂 7mg/L,增殖系数为 7.2; 试管苗生根的最佳培养基为1/2 MS + NAA 0.5 mg/L + IBA 0.2 mg/L + 6-BA 0.05 mg/L + 蔗糖 20 mg/L + 琼脂 7 mg/L,生根率为100％。     

红花小孢子培养与胚状体诱导研究

小孢子培养是创造单倍体和双单倍体的重要途径,对提高红花的育种效率具有重要意义。为了研究红花游离小孢子的高效培养体系,用20份红花材料研究花药及小孢子培养中影响愈伤组织生长和胚发生的关键因素。结果表明,小孢子发育时期、红花品种、基本培养基和激素浓度是影响红花诱导愈伤组织的关键因素。花药培养的愈伤及胚诱导率高于游离小孢子,且受基因型影响。单核靠边期管状花长度为 0.45～0.50 cm时,诱导成功率达到68.32%。供试的20份红花材料中,有11份诱导出了愈伤组织,有1份分化出了胚状愈伤,诱导成功率为15.79%。分化培养最适培养基组合为1/2 MS+B5+ 6-BA 1.0 mg/L + NAA 1.0 mg/L;小孢子悬浮培养最适培养基激素浓度以添加6-BA 4.0 mg/L 和NAA 0.5 mg/L效果最好,诱导愈伤率为22.5%。     

火龙果茎段愈伤组织诱导及再生体系的建立

为了进一步改良火龙果品种,提高产量,以红皮红肉型火龙果紫红龙幼嫩茎段为试材,通过不同植物生长调节剂及浓度配比筛选出适宜火龙果愈伤组织诱导、不定芽再生及生根成苗的培养基,以建立稳定、快速、高效的火龙果再生体系.结果表明:高浓度的TDZ有利于茎段愈伤组织的形成,但不利于不定芽的再生,纵接比横接更利于愈伤组织和丛生芽的诱导,TDZ、2,4-D和NAA 3种生长调节剂通过正交试验筛选的愈伤组织和丛生芽诱导的最适培养基为:MS +2,4-D 1.0 mg·L-1 +TDZ0.4 mg·L-1+ NAA 0.5 mg· L-,愈伤组织诱导率为89.1％,丛生芽诱导率高达94.0％;生根诱导最适培养基为MS+ CCC 0.5 mg· L-1+6-BA 3.0 mg· L-1+ AC 200 mg· L-1,生根率达到97％,平均根数7.0条每株,平均根长达10.3 cm.     

大花卷丹百合组培快繁技术研究

为获得大花卷丹百合的优质种苗，促进其规模化生产，以大花卷丹百合的鳞片为外植体，采用MS、N6、B5培养基，添加激素NAA、6-BA、GA3，进行了大花卷丹百合的快繁技术研究。结果表明，外植体在N6培养基中产生愈伤组织最快、效果最好。愈伤组织及不定芽诱导最佳培养基配方为N6+1.0 mg/L 6-BA+0.1 mg/L NAA；不定芽增殖最佳培养基为N6+0.5 mg/L 6-BA+0.1 mg/L NAA+1.0 mg/L GA3。NAA诱导小鳞茎效果最佳，最适培养基为 N6+1.0 mg/L NAA；促进小鳞茎膨大生根要在诱导鳞茎的基础上加入IBA，即最适培养基为N6+0.1 mg/L NAA+2.0 mg/L IBA。     

江南牡丹茎段愈伤组织诱导与植株再生

为探讨不同培养基、不同植物生长调节剂对江南牡丹茎段愈伤组织诱导及植株再生的影响,本研究以江南牡丹凤丹幼嫩茎段为材料,通过愈伤组织途径建立了植株再生体系。结果表明:改良MS培养基为牡丹茎段愈伤组织诱导的最佳培养基,愈伤组织最高诱导率为93.3%,最佳的培养基组合为改良MS+2,4-D0.2mg·L-1+6-BA2.0 mg·L-1+NAA0.3 mg·L-1。在愈伤组织分化过程中,加入KT0.2mg·L-1效果最好,有机物也能促进愈伤组织分化,其中加入水解酪蛋白300 mg·L-1效果最佳。牡丹茎段愈伤组织分化培养基为改良MS+KT0.2 mg·L-1+6-BA0.3 mg·L-1+NAA0.1 mg·L-1,分化率为37.8%,牡丹愈伤组织不定芽在1/2MS+IBA0.2 mg·L-1条件下能够诱导生根,诱导率为最高的13.3%。本研究结果将为进一步开展江南牡丹的高效再生体系和转基因育种等研究提供技术支持和理论依据。     

钻石玫瑰的组织培养与快繁研究

研究表明,适宜钻石玫瑰离体芽诱导分化的培养基为MS 6-BA0．50 mg／L NAA0．10～0．20 mg／L;适宜丛生芽继代增殖的培养基为MS 6-BA1．00 mg／L NAA0．10～0．20 mg／L;适宜试管苗生根的培养基为1/2MS NAA0．10 mg／L,其生根率达90％。     

观赏羽衣甘蓝高频再生体系的建立

观赏羽衣甘蓝是一种赏食兼用的耐冻优良景观植物。为了通过基因工程手段赋予其抗虫性,并进一步提高其低温耐受性,获得新的抗性种质,本研究以优良育种品系为试材,详细探讨了影响离体培养不定芽再生的因素,建立了高效再生体系。以8份不同类型羽衣甘蓝基因型的带柄子叶、子叶、下胚轴为外植体,研究了不同基因型、不同外植体、不同的培养基激素浓度配比及添加AgNO3对不定芽诱导的影响。结果表明:无论基因型及使用的培养基,带柄子叶均为最佳外植体;不同的基因型、不同外植体其最佳的芽诱导培养基不同;筛选出两份材料,其带柄子叶分别在L6(MS+6-BA1.0mg/L+NAA0.1mg/L)及L3(MS+6-BA1.5mg/L)培养基中不定芽诱导率为100%,下胚轴诱导率最高也能达88.33%;培养基中添加4mg/L AgNO3不利于羽衣甘蓝的不定芽诱导;再生株生根以MS+NAA0.1mg/L效果好,生根率可达100%。     

日本臭菘体细胞胚胎发生及植株再生体系的建立

以日本臭菘幼叶为外植体,应用均匀设计法筛选其最适合的胚性愈伤组织及胚性细胞复合体诱导、体细胞胚胎发育及植株再生的培养基配方,建立日本臭菘体细胞胚胎发生体系。结果表明,LS+6-BA 1.0 mg/L+2,4-D 2.0 mg/L+IAA 0.1 mg/L适宜日本臭菘幼叶胚性愈伤组织及胚性细胞复合体诱导,诱导率为98%;LS+6-BA 0.50 mg/L+NAA 0.10 mg/L+IAA 0.10 mg/L最适宜体胚发育及植株再生,体胚萌发率为100%,萌发的体胚在发育培养基上继续培养42 d后全部发育成完整植株。对不同阶段培养材料的形态结构及超微结构的观察证明,成功建立了日本臭菘体细胞发生及植株再生体系。     

草莓茎尖组织培养技术研究

为建立完善的草莓组培快繁体系,解决种苗退化问题,以当地草莓主栽品种红颜茎尖为试材,设置0.1%升汞和0.1%升汞+2%吐温-80溶液2种外植体消毒处理,以MS为基本培养基,分别添加不同浓度6-苄氨基腺嘌呤(6-BA)和萘乙酸(NAA)的6个诱导和继代增殖培养基、5个生根培养基,研究草莓茎尖外植体消毒最佳方式与时间, 筛选诱导、继代增殖及生根培养的最佳培养基。结果表明,0.1%升汞+2%吐温-80溶液处理8 min时草莓茎尖污染率及褐化率较低,萌发率最高,可达82.3%,为最佳的消毒方式。外植体在MS+1.0 mg/L 6-BA+0.2 mg/L NAA培养基中,可诱导出更多的健壮不定芽,萌发率为83.3%,为最佳诱导培养基;适宜的继代增殖培养基为 MS+1.0 mg/L 6-BA +0.02 mg/LNAA,增殖系数为4.5%;1/2MS+0.01 mg/L NAA为最佳生根培养基,生根率高达100％。     

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,     

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.     

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.     

Properties of anaerobically digested and composted municipal solid waste assessed by linking soil mesofauna dynamics and nitrogen modelling

We have studied the effect of anaerobically digested (ADMSW) and composted municipal solid waste (CMSW) on mineralization and foodweb dynamics to verify the hypothesis that ADMSW would immobilize N right after addition to soil in contrast to addition with CMSW. Another hypothesis was that the mesofauna (enchytraeids and microarthropods) would stimulate N release from the decomposer community. We measured excretion of -N and urea-N from the mesofauna and hypothesized that enchytraeids would release urea. ADMSW and CMSW were amended to pots with sandy loam and barley. The pots were divided into treatments with or without mesofauna. Mesofauna, plant N and biomass, soil N and ergosterol (fungal biomass) were measured over a 113-day period of four equidistant samplings. Soil respiration, N mineralization and N release by the mesofauna were modelled from concurrent studies. ADMSW- and CMSW-treated soils initially (<20 days) immobilized N. The amendments did not increase plant growth substantially, and this was probably due to N-limitation in the early stages of plant growth. Enchytraeid abundance was about three times higher in ADMSW- than CMSW-treated soils, indicating that ADMSW contained more labile compounds, bacteria, and microfauna. The mesofauna did not affect N-content, but the cumulated -N excreted by the mesofauna was estimated to be substantial and about one-fifth of total plant N in ADMSW. An explanation for this discrepancy might be that in the absence of the mesofauna, other members of the detrivore and microbivore community performed the mesofauna’s function. Neither enchytraeids nor microarthropods excreted urea.     

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,     

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,     

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.