类菌原体(MLO)引起的香椿带化病

在陕西省紫阳县四旁栽植的香椿Toona sinensis(A. Juss.)Roem。多处发生带化病。据在该县毛坝等地区的调查961株香椿树,有带化病树50株,一般发病率约5%,严重地区发病率达20%以上,而且病害仍在发展。此病在河南信阳亦有零星分布。树木带化病又称扁枝病,感病的香椿树最显著的症状是新生的枝条呈扁平的带状,并在病枝上伴有簇生枝及小叶现象。每年3、4月间,新发病株是在4、5年生香椿树或经平茬后第3年萌发的枝条生长呈扁平枝状,尖端卷曲或扭曲向内再向上生长,如同一把大刀,老乡形象地称为春秋刀(图版Ⅰ-5)。有在病树上数个病枝条并生在一起形成铲状。连续生长几年病变枝条变细,弯曲盘结生长形成一个大疙瘩。严重影响香椿的生长和木材的利用,此病的蔓延亦阻碍丁香椿树的发展。本文报道了在香椿带化病枝的韧皮部发现类菌原体(MLO)。在高等木本植物上被类原核微生物感染,表现带化、扁枝症状的病害,尚属第一次用电镜观察到。     

油桐枝梢上一新寄生菌

1964—1970年间,四川泸县玉蝉林业试验站建立油桐品种园,曾发生严重嫩梢枯死的情况。至1981年,油桐枯枝率达46.0％,产量下降57.3％,1982年下降为66.5％。采集油桐枯枝病菌,经人工培养、接种试验,证明为致病菌,称油桐枯枝病。现鉴定为丛赤壳(Nectria Fr.)一新种。     

火炬松枯梢病的发生与林分密度有关

我县花岗林场1974年引种火炬松,1975年采取不同密度(3×3、4×4、5×5、6×6米)营造了1024亩用材林和种子林。1986年9月调查发现13年生树木生长不正常,林木密度大的发生严重枯梢,病株率达100％,病梢率达94.3％,少数树木已处于半枯死状态。1987年在密度     

油橄榄炭疽病及其防治研究城固县柑桔育苗场

油橄榄炭疽病在陕西汉中地区普遍发生。该病危害油橄榄各部器官,但只有在果实和叶片上呈现典型症状。发病严重时引起落果、落叶、枝梢枯死,树势生长衰弱。病果含油率降低30.4—42.3％。油橄榄炭疽病病原菌Colletotrichum gloeosporioides Penz.[异名Glocosporium olivarum Alm.]在陕西汉中地区尚未发现有性时代。初次侵染源为病枯枝、病叶和病落果所产生的新的分生孢子。该病每年4月下旬在幼嫩叶尖端出现新病斑,5月中旬花发病,6月中下旬果实开始发病,11月上旬达发病高峰。高湿条件下有利于病害发生发展。室内外接种均能发病,潜育期2—7天。抗病性差异可能与不同品种果实表皮细胞层次及缀密度有关,爱桑(Elbasan)、米札(Mixaj)较抗病。冬春剪除油橄榄病枯枝,清除病叶和病落果,结合使用1％波尔多液和50％退菌特800倍液防治油橄榄炭疽病效果显著。     

油桐栽培经验点滴

油桐是一种生长快,一般三四年就有收益的经济林木,但产量低。为了尽快地提高产量,我们从一九八五年起对油桐栽培技术的有关问题进行了初步的摸索,现简介如下: 一、造林地坡位的选择疏松、深厚、肥沃、湿润且排水良好的土壤,利于油桐生长。而土壤肥力与水分状况和一定的坡位、坡度等有关系。经调查,同一向阳的山凹地四年生油桐树,     

油桐角斑病化学防治试验

油桐角斑病(Cercospora aleuritidis Miyake)是我县油桐林区危害最严重的一种病害,感病率达100%,感病指数80%。长期以来给油桐生产造成了严重的经济损失,是油桐生产上急待解决的问题,为此,我们于1982年配合省林科所对该病进行了多种化学药剂的防治试验。现将结果整理如下:     

油桐橙斑白条天牛生物学特性及其防治

橙斑白条天牛是油桐树上的1种重要害虫。该虫在河南汝阳3 a发生1代,以幼虫或成虫在树干内越冬。成虫在5月下旬至6月下旬为产卵盛期。一般1头雌虫1代产卵3～7次,每次产卵2～5粒。9月上旬停食死亡。其寿命为300 d左右。幼虫卵经5～8 d孵化为幼虫,7月下旬至8月中旬为孵化盛期。该天牛成虫、幼虫同时危害油桐,以幼虫蛀干危害最严重。成虫啃食1～3 a生枝条的皮,甚至咬断枝条。用40%氧化乐果乳油1︰1倍液涂干防治效果最为理想,对1～2龄幼虫和成虫杀伤力达100%,对3龄以上幼虫杀伤力达96%左右。     

农民房前屋后栽植的油桐生长结果情况调查

油桐是我国特有的木本油料树种之一,栽培历史已有一千二百多年.桐油是我国传统的出口商品,在国际市场上享有崇高的声誉.我省人口稠密,土地珍贵,桐林面积不大,近年来油桐面积还有下降的趋势,这就使得桐油非常紧缺的状况变得更为突出.为改变桐油供需矛盾,如进行大面积成片种植尚有一定的困难.因此,号召有条件的农户,利用家前屋后,四旁荒地荒滩种植油桐树,解决自用桐油问题,便是一个主要途径之一.本文调查的是溧水县渔歌乡傅家边村上任庄植桐农户任启斌利用房前屋后栽植的油桐树生长情况.油桐栽植与管理(一)林地概况任启斌房前屋后栽植的油桐地系石头岗地,黄棕沙壤土,土层薄,肥力差.(二)植苗造林栽植前挖成50×50×50厘米的穴,穴内施厩杂肥一担(35—40公斤).苗木为1—2年     

油桐良种葡萄桐

葡萄桐,是泸溪县广大贫下中农在长期经营油桐生产中,经过长期的株选(选生长旺盛、树冠发达、年年丰产、抗害力强、10年生左右的单株)、枝选(丛生性强的、一结果枝在15个以上的)、果选(大而圆、皮薄而光滑、果尖短而无病虫害的),而精心选育出来的油桐优良品种。此树,树冠平展如伞,果实簇生树梢,种植后两年开盘,三年开始结果,四年之后进入盛果期,一般每一果技结果都在10个以上,少的也有5个,多的达50余个,单生果罕见。4—10年生的桐林,结果枝在70%以     

夹竹桃丛枝病研究初探

夹竹桃是一种广泛应用于园林观赏的重要花卉。但由于丛枝病的发生,造成了死亡,影响了景观效果。该病在夹竹桃栽植地区均有发生,其中以红花夹竹桃(Nerium indicum Mill)尤为严重,白花夹竹桃(N. indicum cv. Paihua)少发病,黄花夹竹桃(Thevetia peruviana)抗病。在广州,红花夹竹桃的发病率达60％以上,感病指数30％,严重的整株枯死。在深圳市水库公园的红花夹竹桃发病率达100％,死亡率达70％。此病多危害5年生以上的老树,1—5年生的植     

厚壁毛竹春季光合日变化及其与主要环境因子的关系初探

光合作用是植物重要的生理过程之一,是植物物质生长的基础[1],对植物生长发育具有重要意义.光合作用的强弱取决于树木的遗传性和环境条件的影响,由于光合作用与树木生长地环境条件的密切关系,光合强度在引种驯化中常作为评价树木适应性的重要指标.树木对某一地区的适应性,是其对该地区各种环境条件的生理生态反应的综合表象.     

廊坊市建成区森林生态系统生态资产动态分析与预测

使用市场价格替代法、影子工程价格法及现行市价法等评价方法,对廊坊市建成区森林涵养水源、保持土壤、净化空气、固碳制氧等服务功能进行了初步估算。以2000年为基准年,以2001—2005年、2006—2010年及2011—2015年为估算时段综合分析、预测廊坊市建成区森林生态系统生态资产的动态变化趋势。结果显示:廊坊市建成区森林生态系统生态资产2000年、2005年、2010年及2015年分别为1 448.818 6万元、2 733.072 4万元、4 098.457 6万元及4 692.988 4万元,人均生态资产占有量分别为43.573 5元/人、74.268 3元/人、90.076 0元/人及86.427元/人;2001—2005年、2006—2010年及2011—2015年3个评价时段中生态资产增长率依次为88.641 5%,49.957 9%及14.506 3%,而同期人均生态资产占有量增长率依次为70.443 7%,21.284 6%及-4.051 0%。     

印度尼西亚棕榈藤业考察体会

考察认为印度尼西亚的棕榈藤资源丰富,藤条生产潜力大;人工种植施法自然,初植密度低,不施化学肥料,依靠天然淤泥肥地;重视天然资源保护,鼓励人工培育资源;单纯依靠棕榈藤作为发展手段效果不尽如人意;藤产品成为印度尼西亚国家的纪念品之一。     

Carbon and nitrogen dynamics in topsoils along forest conversion sequences in the Ore Mountains and the Saxonian lowland, Germany

Carbon and nitrogen stocks and their medium-term and readily decomposable fractions in topsoils were compared in relation to soil microbial biomass and activity along sequences from coniferous to deciduous stands. The study was carried out in the Ore Mountains and the Saxonian lowland, representing two typical natural regions in Saxony, Germany. In accordance with current forest conversion practices, the investigation sites represent different stands: mature conifer stands of Norway spruce (Picea abies (L.) Karst.) and Scots pine (Pinus sylvestris L.) (type A); Norway Scots spruce and pine with advanced plantings of European beech (Fagus sylvatica L.) or European beech/Common oak (Quercus petreae Liebl.) (type B); and mature deciduous stands of European beech and European beech/Common oak (type C). The investigated forest sites can be grouped into three silvicultural situations according to the development from coniferous stands to advanced plantings and finally mature deciduous forests (chronosequence A–B–C). The organic layer (L, F and H horizons) and uppermost mineral soil (0–10 cm) were analysed for potential C mineralisation, microbial biomass, concentrations of total C and N (TOC and TN) and for medium-term and readily decomposable C and N fractions, obtained by hot- and cold-water extraction respectively. The results showed an increase in organic layer thickness and mass as well as TOC and TN stocks along the forest sequences in the lowland. Yet, underplanted sites with two storeys revealed higher organic layer mass as well as TOC and TN stocks as compared to coniferous and deciduous stands. Stocks of hot- and cold-water-extractable C and N in relation to microbial biomass and its activity revealed a high turnover activity in deeper organic horizons of deciduous forests compared to coniferous stands. The stand-specific differentiation is discussed in relation to microbial biomass, litter quantity and quality and forest structure, but also with respect to the site-specific climatic factors and water budget as well as liming and fly-ash impacts. Results indicate higher dynamics in deciduous stands in the lowland especially during the initial turnover phase. The elevated microbial activity in deeper organic horizons of deciduous litter-influenced sites in spring is discussed as a specific indicator for long-term C sequestration potential as besides C mineralisation organic compounds are humified and thus, can be stored in the organic layer or in deeper soil horizons. Due to liming activities, stand-specific effects on organic matter turnover dynamics have evened out today in the Ore mountain region, but will presumably occur again once base saturation decreases. Here, the stand-specific effect on microbial biomass can currently be seen again as C_mic in the L horizon increased from spruce to beech. Our study sites in the lowland revealed no significant fly-ash impact. Differences between sites were evaluated by calculating the discriminance function. TOC and TN as well as medium-term degradable C and N were defined in this study as indicators for turnover dynamics along forest conversion sites.     

枸杞容器扦插育苗技术研究

通过单因素试验设计研究了不同类别促生根剂(W)对枸杞插穗生根率高低、生根条数多少的影响;还通过正交试验设计L8(27)方法来研究了促生根剂浓度(E)、母株采穗部位(C)、不同木质化插条(P)及插条下部径粗(Y)对枸杞扦插生根率高低、生根数多少的影响。结果证明:使用促生根剂ABT-1#(W2)来处理插条时扦插效果最好,平均生根率高达89.7%、生根数多达11.2条;采用糊状的浓度为700ppm(E2)促生根剂ABT-1#来粘母株下部(C2)所剪下部径粗为0.8~1.2mm(Y1)的未木质化的插条(P1)时,即采用E2C2Y1P1组合时对枸杞扦插效果最佳,平均生根率多达95.3%、生根数高达15.6条。     

高岭土/木质素磺酸钠-g-AA-AM复合高吸水树脂的制备

以木质素磺酸钠(LS-Na)、丙烯酸(AA)、丙烯酰胺(AM)为原料,高岭土(Kaolin)为无机添加剂,过硫酸钾(KPS)为引发剂,N,N’-亚甲基双丙烯酰胺(NMBA)为交联剂,通过溶液聚合制备高岭土/木质素磺酸钠-g-AA-AM复合高吸水树脂(LPAAM)。选用正交试验设计方法,以蒸馏水和0.9%NaCl溶液中的平衡吸液倍率为评价参数得到了较优配方:m(AM):m(AA)=1:1,m(KPS)=1.0%,m(NMBA)=0.1%,pH=3。将上述配方制备的LPAAM以不同浓度NaOH于90℃皂化2h,得到皂化后的LPAAM,该树脂在蒸馏水和0.9%NaCl溶液中的平衡吸液倍率分别为1003及89g·g-1。     

褐斑凤蝶和斑凤蝶幼期形态特征记述及生物学初步观察

记述了褐斑凤蝶(Chilasa agestor(Gray))和斑凤蝶(C.clytia(Linnaeus))的幼期形态特征、成虫和幼虫的主要习性.在四川峨眉,褐斑凤蝶1年1代,以滞育蛹越夏、越冬;成虫发生期在春季,访花;卵散产,幼虫5龄,分散栖息;以樟(Cinnamoneum camphors(Linn.)Presl)和楠木(Phoebe zhennan S.Lee et F.N.Wei)为寄主.在西双版纳国家级自然保护区关坪管理站,斑凤蝶实验种群1年发生5代,以蛹越冬;成虫访花,卵散产,幼虫5龄,分散栖息,末龄幼虫有鲜艳的警戒色;以玉兰叶木姜子(Litsea magnoliifolia Young et P.H.Huang)和潺搞木姜子(Litsea glutinosa (Lour.)C.B.Rob.)为寄主.     

Fixation Property of Copper Triazole Wood Preservatives

According to AWPA E11-2006 standard,copper fixation rates of several copper-based formulations,such as ammoniacal copper,amine copper,and ammoniacal-ethanolamine copper,as well as alkaline copper quaternary(ACQ),were tested and compared in this paper.And the fixation rates of tebuconazole(TEB) and propiconazole(PPZ) in several formulations,such as copper azole,emulsified type and solvent type,were also compared.The determination of copper content in the leachate was analyzed by atomic absorption spectrom...     

Ecological and economical significance of homestead forest to the household of the offshore island in Bangladesh

An explanatory survey was conducted to assess the contribution of plant diversity to the ecological and socio-economic condition of the rural household in the offshore island of Bangladesh.Assessment was done by means of multistage random sampling.The homestead sizes of the study area were classified into 3 groups viz,large (>0.25 ha),medium (0.05-0.25 ha) and small (<0.05 ha) based on the result obtained from a preliminary survey,and a total of 45 homesteads,15 from each group,were selected randomly for the study.The average annual income from homestead's plant diversity varied from Tk 5730.00 (US$95.5) to Tk 17500.00 (US$291.67).The rural people were mainly dependent on their homegarden for woodfuel and nutritional requirement as forest was unavailable in the island.The rural people here also cultivated the plant species as a safety measure from frequent cyclone.Constraints hindering the development of homestead plantation were identified and suggestions were given such as the adequate supply of seedlings of fast growing native species and conservation of endangered species to meet the demand of the household as well as to keep ecological balance.     

Evaluation of aqueous and ethanolic extracts of saffron, Crocus sativus L., and its constituents, safranal and crocin in allodynia and hyperalgesia induced by chronic constriction injury model of neuropathic pain in rats

The current study was designed to evaluate therapeutic potential of systemically administered ethanolic and aqueous extracts of saffron as well as its bioactive ingredients, safranal and crocin, in chronic constriction injury (CCI)-induced neuropathic pain in rats. The von Frey filaments, acetone drop, and radiant heat test were performed to assess the degree of mechanical allodynia, thermal allodynia and thermal hyperalgesia respectively, at different time intervals, i.e., one day before surgery and 3, 5, 7 and 10 days post surgery. The ambulatory behavior was evaluated using the open field test. A 7-day treatment with the ethanolic and aqueous extracts (50,100 and 200 mg/kg, i.p.) and safranal (0.025, 0.05 and 0.1 mg/kg, i.p.), attenuated the behavioral symptoms of neuropathic pain in a dose dependent manner. Crocin even at the high dose (50 mg/kg) failed to produce any protective role. However, gabapentine (100 mg/kg) as a reference drug significantly alleviated all behavioral manifestations of neuropathic pain compared to control group. In conclusion, the results of this study suggest that ethanolic and aqueous extracts of saffron as well as safranal could be useful in treatment of different kinds of neuropathic pains and as an adjuvant to conventional medicines.