松材线虫荧光显微观察方法比较研究

利用4,6-联脒-2-苯基吲哚（DAPI）、苯胺蓝、吖啶橙等染料对松材线虫进行染色处理,荧光显微镜观察发现松十才线虫经不同的荧光染料染色后,产生不同的荧光效果,且荧光效果均强于其自发荧光。尤其以吖啶橙荧光染色山专为明显,雄性松材线虫的生殖器官交合伞可以表现出不同颜色的荧光效果。这些结果对于利用荧光染色的方法研究松材线虫形态特征及其分类鉴定均有指导意义。     

荧光假单胞菌对湿地松幼林生长量的影响

将荧光假单胞菌Q2-87和1M1-96两菌株施用于1 a生、2 a生和3 a生的湿地松幼林;一个湿地松生长高峰期后,分析自然状态下幼林的生长规律,同时进行施菌前和施菌后苗高和地径的比较。结果表明:13片自然状态下生长的幼林生长情况符合前人总结的规律;2所有施菌的湿地松幼林经过一个生长高峰期后,高增长率均未得到显著提高;3施菌的1 a生幼林地径增长率提高极显著,施菌的2 a生幼林地径增长率提高显著,而施菌的3 a生幼林地径增长率提高不显著。通过分析,认为施菌的3 a生湿地松的地径增长率未提高不显著,原因是该龄期的湿地松对2,4-DAPG已经不敏感。因此,本文的结论是荧光假单胞菌Q2-87和1M1-96通过其产生的2,4-DAPG主要作用于低龄(2 a生以下)的湿地松,并导致其产生类似于生长素作用产生的促生效应,从而使湿地松地径明显地增长。     

PF7-5对烟草角斑病的室内及大田防治效果

为验证荧光假单胞杆菌PF7-5对烟草角斑病的生物防治效果,设计了荧光假单胞杆菌PF7-5对烟草角斑病菌的室内和大田抑菌试验。结果表明,室内试验中荧光假单胞杆菌PF7-5代谢产物对烟草角斑病的抑菌效果达到71%,大田试验中PF7-5活菌的50倍稀释液田间防治效果达87.34%,说明荧光假单胞杆菌PF7-5对烟草角斑病有一定的防治效果。     

毛竹组织荧光染色显微观察方法的研究

采用3种不同的荧光染料,对不同发育阶段的毛竹组织进行染色处理,分析其染色效果。应用荧光显微技术,DAP I(4,′6-二脒基-2-苯基吲哚)的着色能力强,呈现出明亮的浅蓝色荧光,细胞核的荧光增强,尤其在组织细胞生长发育早期,细胞基本处于分生状态,细胞核和核仁都较大,染色效果好。苯胺蓝染色对基本组织细胞内的淀粉颗粒效果好,荧光强度与淀粉颗粒的大小有关。吖啶橙染色方法可以使毛竹不同的组织细胞和成分呈现不同的荧光,从而将它们明显地区分观察。不同的制片方法对染色也有影响。     

荧光假单胞菌的溶磷机制及其在杨树菌根际的定殖动态

【目的】探究荧光假单胞菌菌株JW-JS1的溶磷能力及其在杨树根际和菌根际的定殖动态,揭示菌株的溶磷机制并进一步阐明溶磷细菌与外生菌根真菌的互作机制,为杨树专用复合菌剂的开发与应用提供理论依据。【方法】通过液体培养试验分析荧光假单胞菌菌株JW-JS1培养液可溶性磷含量、p H和可滴定酸含量的变化,采用高效液相色谱(HPLC)法测定有机酸种类和含量,利用抗利福平标记法筛选稳定的标记菌株,运用灌根法研究其在杨树根际和菌根际的定殖动态。【结果】1) JW-JS1菌株培养液可溶性磷含量随接种时间延长逐渐增加,培养液pH与可溶性磷含量呈极显著负相关(r=-0.889~(**)),可滴定酸含量与可溶性磷含量呈极显著正相关(r=0.958~(**));2) JW-JS1菌株分泌的总有机酸量(434.39 mg·L~(-1))明显高于CK (25.94 mg·L~(-1))(P0.05),共检测出草酸、酒石酸、柠檬酸、顺丁烯二酸和反丁烯二酸5种有机酸,其中,草酸含量(273.69 mg·L~(-1))明显高于其他种类有机酸,约占总有机酸量的63.01%;3)筛选出含有300μg·mL~(-1)利福平抗性的标记菌株JW-JS1~(Rif),与原始菌株相比,其菌落形态和溶磷能力均未发生明显变化(P0.05);4)标记菌株在杨树根际和菌根际均能长期稳定存活并保持一定的定殖数量,随接种时间延长定殖数量呈下降趋势,定殖动态基本一致,其中,接种50天后定殖数量分别为5.2×10~4和4.5×10~4cfu·g~(-1)。【结论】荧光假单胞菌菌株JW-JS1的溶磷能力与培养液pH、可滴定酸含量和有机酸密切相关,特别是菌株分泌的草酸可能在溶磷过程中发挥重要作用。荧光假单胞菌菌株JW-JS1在杨树根际和菌根际均能长期稳定存活并保持一定的定殖数量。荧光假单胞菌菌株JW-JS1与红绒盖牛肝菌Xc是构建杨树专用功能复合微生物肥料的理想材料。     

杨树解磷细菌蜡状芽孢杆菌和荧光假单胞菌发酵罐扩繁条件优化

对杨树高效解磷细菌蜡状芽孢杆菌(Bacillus cereus)JYZ-SD1和荧光假单胞菌(Pseudomonas fluorescens)JW-JS1在3L发酵罐里发酵条件进行优化。结果显示这两株解磷细菌在72h内都是接种量20%、转速400 r/min、通气量100ln/h条件下菌体生长量最大。为将这两株杨树根际解磷细菌更高效、更大量的扩繁提供参考依据。     

树木防冻防病膜对冰核细菌抑菌效果研究

为了研制适合于树木的防冻防病剂,预防树木越冬伤害及由冻害诱发的溃疡病等问题,研究了树木防冻防病膜对丁香假单胞菌和菠萝泛生氏菌2种冰核细菌的抑菌效果,并与农用链霉素进行比较。采用滤纸片扩散法对比3个浓度(0.3‰、0.6‰和1‰)下农用链霉素和防冻防病膜对2种冰核细菌抑制效果。结果表明:与农用链霉素相比,防冻防病膜对2种冰核细菌的抑制效果较好,且抑菌效果随着药剂浓度的增大而增大。在设置的最高试验浓度下,树木防冻防病膜对丁香假单胞菌和菠萝泛生氏菌的抑菌直径分别为10.1 mm和19.0 mm,树木防冻防病膜对菠萝泛生氏菌抑制效果好于对丁香假单胞菌的抑制效果。     

荧光假单胞菌与红绒盖牛肝菌共接种对杨树根际土壤酶活性及微生物多样性的影响

【目的】探究荧光假单胞菌与红绒盖牛肝菌共接种条件下NL-895杨根际土壤酶活性和土壤微生物功能多样性的变化,从微生态水平揭示溶磷细菌与外生菌根真菌互作对NL-895杨的促生机制。【方法】采用盆栽试验考察荧光假单胞菌JW-JS1与红绒盖牛肝菌(Xc)共接种后NL-895杨根际土壤酶(酸性磷酸酶、脱氢酶和转化酶)的活性变化,并通过BIOLOG微孔板法分析共接种对NL-895杨根际土壤微生物群落和功能多样性的影响。【结果】从整体趋势来看,不同接种处理后NL-895杨根际土壤酶活性均有所增强,土壤酸性磷酸酶、脱氢酶和转化酶活性均大于对照,其中,共接种JW-JS1+Xc处理对土壤酸性磷酸酶和转化酶活性的促进最为明显;接种150天后,不同接种处理土壤微生物的AWCD值均高于CK(培养24～48 h除外),且随着培养时间的延长呈先上升后稳定的趋势;培养96 h后,共接种JW-JS1+Xc处理土壤微生物McIntosh优势度指数和碳源利用丰富度指数显著高于单接种Xc或JW-JS1和CK(P<0.05),而Shannon丰富度指数和Simpson优势度指数显著低于单接种Xc或JW-JS1和CK(P<0.05);不同接种处理NL-895杨根际土壤微生物对BIOLOG微孔板中6大类碳源的利用能力差异显著(P<0.05)。【结论】荧光假单胞菌JW-JS1与外生菌根真菌Xc共接种对NL-895杨根际土壤酶活性和土壤微生物功能多样性的提高具有一定的促进作用,有利于其土壤肥力的改善,进而促进NL-895杨的生长。与单接种相比,溶磷细菌与外生菌根真菌共接种可更有效地提高杨树根际土壤酶活性和土壤微生物多样性。     

玉兰叶片叶绿素荧光特性的研究

用叶绿素荧光技术测定玉兰不同无性系叶片的叶绿素荧光参数,结果表明:玉兰同一叶片不同部位叶绿素荧光参数(Fv/Fm)存在着差异,叶片基部、叶片中左、右部高于叶片尖部.南北两侧Fv/Fm差异不显著.叶绿素荧光测定的功能叶片区域很大,从整株来看,从树冠顶层第2轮开始到树冠底层第2轮结束,中间的叶片都可以看成是功能叶片.叶绿素荧光参数日变化表现为降-升-降-升的动态曲线.8:00～10:00时为最高.18:00时逐渐上升,到20:00～22:00时上升到原来状态.     

松材线虫携带细菌产生抑制真菌的物质

研究发现松材线虫携带的两株荧光假单胞菌GcM5-1A、ZM4A和恶臭假单胞菌ZpB1-2A具有抑制真菌菌丝生长的作用.首先对供试的8个细菌菌株进行抑菌活性生物测定,从中筛选出3个具有抑菌活性的细菌菌株;接着对细菌培养液及滤液、死细菌及活细菌进行生物测定;最后对细菌代谢物的性质进行生物测定.实验证明抑制真菌菌丝生长的活性成分为松材线虫携带细菌的挥发性代谢产物.     

In vitro effects of Laccaria bicolor S238 N and Pseudomonas fluorescens strain BBc6 on rooting of de-rooted shoot hypocotyls of Norway spruce

The ectomycorrhizal fungus Laccaria bicolor S238 N and the bacterium Pseudomonas fluorescens BBc6 were used separately and in combination to induce in vitro rooting of de-rooted shoot hypocotyls of Norway spruce (Picea abies (L.) Karst.). When the culture medium was supplemented with tryptophan, a precursor of indole-3-acetic acid (IAA) synthesis, the presence of the ectomycorrhizal fungus increased the percentage of hypocotyls forming roots; furthermore, both the fungal and bacterial inoculations enhanced the number of roots formed per rooted hypocotyl. Similar results were obtained by adding exogenous IAA (5 and 10 &mgr;M) to the rooting medium. After the rooting phase, the fungal inoculation enhanced adventitious root elongation and branching as well as the aerial growth of the cuttings. Pseudomonas fluorescens BBc6 had no effect on these parameters. The production of IAA by pure cultures of L. bicolor S238 N and P. fluorescens BBc6 was estimated by immunochemical analysis using specific anti-IAA antibodies. Both L. bicolor S238 N and P. fluorescens BBc6 synthesized IAA in pure culture and synthesis was stimulated in the presence of tryptophan. Thus, the effect of the fungus in stimulating adventitious root formation and subsequent elongation and branching can be attributed, at least partially, to the synthesis of IAA by the fungus. The finding that P. fluorescens BBc6 had no effect on root elongation and branching although it produced IAA suggests that either IAA was not the only parameter involved in the stimulation of these processes by L. bicolor S238 N or the bacterium produced other compounds that counteracted the stimulatory effects of IAA on root elongation and branching.     

果园及坡耕地毛竹造林效果研究

不同地类毛竹移栽母竹造林试验表明，新竹株数由多至少依次为：杨梅园、地瓜山、柑桔园、李园、普通山地；新竹质量好坏顺序为杨梅园、柑桔园、地瓜山、李园、普通山地；新竹最大扩展范围由大至小顺序为杨梅园、地瓜山、柑桔园、李园、普通山地。从造林的总体质量看，杨梅园、地瓜坡耕地是最好的毛竹栽植地，柑桔园、李园的毛竹栽植效果也较好，位普通山地造林效果最差。结果可为破耕地及果园套种毛竹提供指导。     

Comparative analysis of some selected macronutrients of soil in orange orchard and degraded forests in Chittagong Hill Tracts, Bangladesh

Status of organic carbon （C）, total nitrogen （N）, available potassium （K）, calcium （Ca） and phosphorus （P） in three different depths （0-5 cm, 5-15 cm and 15-30 cm） on two hill slopes of 35% and 55% in orange orchard cultivated by the Mro tribe of Chittagong Hill. Tracts （CHTs） were evaluated and compared with those in degraded bush forests, through digging three profiles in each land use. The content of all the five nutrients was found to be higher in the soil of orange orchard than in the soil of forest. But the variation was not consistent for both the slopes. The content varied depth wise also, having the highest value in surface soil in case of both the land uses on both the slopes. A mean available K content was significantly higher in orange orchard than in forest on 55% slope, while it was lower on 35% slope. Surface soil contained the nutrients of K and Ca with the amount of 0.2905-mg·g^-1 soil and 3.025-mg·g^-1 soil respectively in the orchard, while 0.1934-mg·g^-1 soil and 1.6083-mg·g^-1 soil were respectively in the forest. Organic carbon and total nitrogen were found more or less similar in surface soil on both the land uses showing a slight difference. Available P was found only in orange orchard, and in forest it was too little in amount to detect by the spectrophotometer. The degraded forests were poor in nutrient content due to high rate of soil erosion, which would be possible to be improved by bringing it under tree cover as proved by the adaptation of orange orchard there.     

农户林地经营效率及其影响因素分析 ——以梅州市农户调研数据为例

在对梅州市的农户林地经营现状开展分析的基础上,运用问卷调查法获取相关数据,再运用 数据包络分析法对其经营效率进行测算,并深入研究影响林业经营效率的因素,结果表明：（1）样本 农户的林地经营效率不高,经营效率均值只有0.442,砂糖桔（Citrus reticulata "Shatangju"）、柚（Citrus maxima）、杉木（Cunninghamia lanceolata）、桉树（Eucalyptus robusta ）和松树（Pinus massoniana）树种 的经营效率各异,松树和砂糖桔的经营效率相比杉木和柚子而言较低;（2）在影响农户林地经营效率的 因素中,林地经营面积、经营树种和资金投入的影响显著,其中林地面积和资金投入与林地经营效率是 正向相关,而农户的年龄、受教育程度、林地经营形式、林地块数等因素对林地经营效率影响不显著。     

Inhibition of Armillaria by bacteria isolated from soils of the Boreal Mixedwood Forest of Ontario

Pseudomonas fluorescens, Pseudomonas spp., Bacillus spp., Enterobacter spp., Serratia spp. and Agrobacterium radiobacter were isolated from root-free soils of the Boreal Mixedwood Forest of Ontario a, nd found to be capable of inhibiting the linear growth of Armillaria ostoyae in vitro. Isolates of P. fluorescens, Bacillus spp. and A. radiobacter were the most effective inhibitors of mycelial growth. To test the ability of the bacteria to suppress rhizomorph formation, A. gallica, which produces rhizomorphs in culture more consistently than does A. ostoyae, was used; only a small fraction of P. fluorescens and Bacillus spp. isolates were capable of preventing in vitro rhizomorph formation by A. gallica.     

Tolerance of citrus rootstock seedlings to saline stress based on their ability to regulate ion uptake and transport

Forty-five-day-old seedlings of sour orange (Citrus aurantium L.) and Citrus macrophylla Wester, the most commonly used rootstocks in lemon orchards, were grown in nutrient solutions containing 1 (control), 10, 20, 30 or 60 mM NaCl for 14 days. The effects of salinity on growth, uptake, transport and accumulation of Cl- and Na+ ions in leaves, stem and four root segments were studied. The 60 mM NaCl treatment reduced leaf dry mass more in C. macrophylla (40%) than in sour orange (20%), whereas it reduced root dry mass more in sour orange (36%) than in C. macrophylla (20%). In C. macrophylla, Cl- and Na+ uptake rates were high at the beginning of the saline treatments, but low at the end of the 14-day experiment. In contrast, sour orange showed high uptake rates at the beginning and end of the experiment. In response to increasing salinity, root and shoot concentrations of Cl- and Na+ increased in sour orange, but not in C. macrophylla. Different loading characteristics of Cl- and Na+ were observed between young and old segments of the root system. In general, old root segments reached quasi-steady-states later than young root segments. These results suggest that sour orange and C. macrophylla have different regulatory mechanisms for uptake and transport of Cl- and Na+.