南亚热带泡桐速生丰产栽培技术

泡桐是速生用材树种，也是重要的外贸出口物质。南亚热带水、光、热条件优越对泡桐的速生丰产非常有利。以下介绍南亚热带的泡桐速生丰产栽培技术。1南亚热带发展泡桐的优越条件（1）南亚热带拥有我国泡桐的优良品种——白花泡桐、南方泡桐、台湾泡桐和杂交泡桐。其中尤以白花泡桐和杂交泡桐两品种为好：生长速度快，自我接干能力强，杆材通直，尖削度小，成材利用率高，抗性好，易于培养高于良材。（2）南亚热带雨热同季，植物生长持续时间长。泡桐在此地的速生期可达3个半月以上，而且冬季气候温和对泡桐不易造成冻害。（3）适地栽培，一…     

渭南市泡桐病虫害发生现状调查

渭南市泡桐病虫害发生现状调查闫银团（渭南市森防站，陕西渭南７１４０００）据对渭南、富平、白水、韩城等县抽样调查，泡桐幼树发病率为１９％～４８％，大树为５４％以上，重区达１００％。在该区危害泡桐的害虫共有３７种，分为叶部害虫，根部害虫和枝干害虫三大类。...     

泡桐丛枝病的抗性与维生素C关系的研究

泡桐丛枝病的抗性与维生素Ｃ关系的研究＊巨关升王蕤周银莲阮大津关键词ＶＣ、ＶＣ氧化酶、抗性、泡桐、丛枝病ＶＣ（又名抗坏血酸）对人体的防病抗病作用早已被人们所认识，但迄今对其功能的了解还在不断的深入。大量实验表明，ＶＣ作为一种天然抗氧化剂在增强机体免疫功...     

泡桐无性系的测定与选优

根据对泡桐31个无性系的生长、抗性和保存率的测定,分析表明不同无性系间的生长、抗性和保存率均存在很大的差异,据此选择出毛白33、毛白23、毛白08、和7401-3(3-1)四种优良无性系,为泡桐优良无性系的选择奠定了基础。     

圆冠泡桐抗逆性研究

河南省濮阳林科所在对圆冠泡桐（Ｐａｕｌｏｗｎｉａ×ｈｅｎａｎｅｎｓｉｓＣ．Ｙ．ＺｈａｎｇｅｔＹ．Ｈ．Ｚｈａｏ）进行研究过程中，按照苗木与大树抗性一致的原理，于１９９１年在睢县林业科技试验开发中心，做了圆冠泡桐抗旱、抗淹、抗盐碱研究，取得了客观结果，并在７年的生产实践中得到了验证。１　抗旱试验试验材料为圆冠泡桐１年生种根，对照为豫林１号泡桐１年生种根。试验方法是，５月４日将温床催根处理好的长１２ｃｍ、粗１ｃｍ的圆冠泡桐、豫林１号泡桐４０个种根分别直埋于４０个盆中。７月２０日当平均苗高达５０ｃｍ时，…     

大袋蛾危害对泡桐生长量的影响

１９９０－１９９２年在安徽省阜阳市和利辛县测定了大袋蛾ＣｌａｎｉａｖａｒｉｅｇａｔａＳｎｅｌｌｅｎ危害兰考泡桐Ｐａｕｌｏｗｎｉａｅｌｏｎｇａｔａ的损叶量和人工模拟危害对泡桐生长量的影响。泡桐的蓄叶量Ｔ（ｃｍ２）与胸径Ｄ（ｃｍ）呈直线关系：Ｔ＝４４５０３．３３６Ｄ－２７２６２７．０４３。大袋蛾幼虫对泡桐的平均损叶量为４７０．９３６ｃｍ２。摘叶量在５０％及其以下时，泡桐生长量没有受到显著影响，摘叶量达到或超过７５％时，生长量即显著下降。泡桐受害允许水平确定为失叶５０％。     

泡桐苗木对丛枝病诱导抗性方法的研究

泡桐丛枝病是我省发生面积最大的林木病害。利用嫁接诱导的育苗方法，可以根本上减轻该病危害。根接当年苗木发病率为１．４７％—４．２８％，皮接第二代苗木发病率为２．３０％—５．３４％，而对照为０．８３—１．０１％。用经过根接苗木造林２年后发病率为０，经过皮接苗木造林２年后发病率为０—４．１７％；而对照发病率为１６．６％—１８．８％。经过诱导处理，抗性差的苗期发病，不发病者产生较强抗病性。     

泡桐丛枝病的抗性与维生素C的关系

泡桐丛枝病的抗性与维生素Ｃ的关系泡桐丛枝病的发生是受逆境损伤（生物及非生物的）后导致酶系统的变化和内源调节物质—激素（细胞分裂素／生长素）比例平衡失调，使得组织分化、器官形成失控而出现的形态上的异常生长。维生素Ｃ含量及维生素Ｃ氧化酶活性与泡桐丛枝病的...     

泡桐优良资源选择研究初报

泡桐是我国特有的速生用材树种,适应性强,适生范围广,具有很高的经济价值.笔者收集了我国20个省、市、自治区,185个县的12个泡桐种类,进行优良资源选择试验,从中选出了在南阳速生、抗性强、适应性强的优良泡桐种类-白花泡桐和兰考泡桐.     

茶翅蝽对植原体的传播能力

经１９９６年至１９９８年室内接种试验,分别比较了人工饲养带毒和自然带毒的杀翅蝽成虫和若虫的传病特点。结果显示：室内人工饲养带毒的３龄、４龄若虫接种泡桐发病率分别达６１．７％和４６．５％,高于自然带毒的若虫１６％的传病率。室内饲带毒成虫的接种发病率为１４．１％,高于自然带毒成虫４．５％的传病率。寄主体内病原的最短潜育期（ＭＩＰ）室内饲毒３龄若虫为３４ｄ,４龄为４５ｄ,成虫处理为２１９ｄ;自然带毒若虫     

Inducible anatomical defense responses in Norway spruce stems and their possible role in induced resistance

Norway spruce (Picea abies (L.) Karst.) trees were preinoculated with a sublethal dose of the blue-stain fungus Ceratocystis polonica Siem. (C. Moreau) 1 to 52 weeks before they were mass inoculated with the same fungus. Trees pretreated 1 week before mass inoculation had similar, severe symptoms of fungal infection as the control trees. Pretreatment 3, 6 or 9 weeks before mass inoculation resulted in effective protection of the trees, reducing pathogenic symptoms by 63-90% relative to the control trees, whereas pretreatment 52 weeks before mass inoculation gave intermediate protection (44-71% reduction in symptoms). Thus, pretreatment induced resistance to the blue-stain fungus in Norway spruce by a process that requires more than 1 week to become activated and protects trees for at least one year after pretreatment. Pretreatment induced formation of traumatic resin ducts (TDs) in the sapwood and swelling and proliferation of polyphenolic parenchyma cells (PP cells) in the phloem. Trees pretreated 3-9 weeks before mass inoculation had more TDs and showed greater swelling of existing PP cells than control trees or trees pretreated 1 week before mass inoculation. We conclude that induced disease resistance in Norway spruce is probably associated with PP cell activation and TD induction, because resistance was enhanced within the same time frame as the induction of these defense responses.     

锥栗对栗疫病的抗性与苯丙氨酸解氨酶的关系

健康的锥栗(Castanea henryi)皮层中,苯丙氨酸解氨酶(PAL)比活力与抗感病性之间不相关.不同抗病性的锥栗品种接种栗疫菌(Cryphonectria parastttca)后,PAL比活力均上升,接种144 h后,PAL比活力抗病性强的品种比抗病性弱的品种高.接种前以及接种后的各个时间内,木质素含量都是抗病品种比感病品种高.绿原酸的含量与品种的抗病性之间不呈规律性的相关,从绿原酸对栗疫菌菌丝生长影响的测定结果可知,锥栗体内的绿原酸浓度不足以影响栗疫菌.可见,接种后的皮层PAL比活力以及接种前、后的皮层木质素含量可作为衡量锥栗抗病性强弱的指标.     

Induction of phenylalanine ammonia lyase activity and control of Sphaeropsis sapinea infection in Pinus radiata by 5-chlorosalicylic acid

Phenylalanine ammonia lyase (PAL) activity increased rapidly in Pinus radiata seedlings after treatment with 2 mm 5-chlorosalicylic acid (5CSA) and peaked after 48 h at four-times the level of the control. Elevation of PAF is often associated with the induction of host resistance mechanisms. Thus, effects of 5CSA on subsequent infection of P. radiata by Sphaeropsis sapinea was investigated. Only one out of 16 seedlings treated with 2 mm 5CSA, 4 days before inoculation, developed deadtop compared to 14 of the controls. The 5CSA was directly inhibitory at this concentration and reduced growth rate of S. sapinea on agar by 27%. However, antifungal activity does not fully account for the observed disease control afforded by 5CSA since 0.5 mm and 0.25 mm 5CSA, which did not inhibit growth of S. sapinea, significantly reduced the incidence of deadtop. Furthermore, 1 mm 5CSA protected seedlings against fresh inoculation challenge for up to 32 days after application. Such durable resistance is unlikely to be attributable to the direct effects of the applied compound and may suggest the involvement of inducible host resistance mechanisms.     

Effect of Betula pendula clone and leaf age on Melampsoridium betulinum rust infection in a field trial

Ten 5‐year‐old Betula pendula clones were studied for their rust resistance in the field. The trees were treated by inoculating 10 leaves on a shoot with Melampsoridium betulinum urediniospore suspension or spraying the control leaves with water. The birch clones differed significantly in their resistance to M. betulinum leaf rust fungus and the clones also varied in their responses to the local rust strain and the inoculated rust strains. However, natural rust infections and inoculation treatment were positively correlated. The older leaves had fewer infections than the younger ones on the tip of the shoot in the control trees, but in the inoculation treatment no significant correlation was found between the leaf ages and rust infection. The factors behind the different leaf susceptibilities are discussed.     

Mechanical injury and fungal infection induce acquired resistance in Norway spruce

Norway spruce trees (Picea abies (L.) Karst.) pretreated by wounding and fungal infection showed highly enhanced resistance to a subsequent challenge inoculation with the pathogenic bluestain fungus Ceratocystis polonica (Siem.) C. Moreau. This is the first time the effectiveness of the constitutive and inducible defenses has been shown to depend on prior wounding and infection in conifers, although such acquired resistance has previously been found in several angiosperms. Trees that were pretreated with a combination of 12 bark wounds (1.6 x 10 cm), four fungal inoculations and four sterile inoculations 1-15 days before mass inoculation with C. polonica at 400 inoculations per square meter over a 0.8 m stem section had significantly shorter necroses in the phloem, less bluestained sapwood, and less dead cambium than untreated control trees. Pretreatment with four fungal or sterile inoculations alone did not lead to enhanced resistance. Pretreatment by bark wounding alone seemed to provide an intermediate degree of resistance compared to bark wounding, fungal inoculations and sterile inoculations combined. All trees had a marked increase in the number of resin ducts in the year of inoculation compared with previous years, suggesting that formation of traumatic resin ducts play an important role in the development and maintainance of enhanced resistance.     

Histopathology of primary needles and mortality associated with white pine blister rust in resistant and susceptible Pinus strobus

White pine blister rust caused by Cronartium ribicola is a damaging non‐native disease of five‐needled pines in North America. Efforts to control the disease and mitigate damage to date have been only somewhat effective. Recent efforts to improve the health of eastern white pine and reestablish the tree as a dominant species in the North Central United States have focused on identification and propagation of disease‐free eastern white pine (Pinus strobus) growing in areas with a high incidence of blister rust. Many of these selections have been shown to resist infection following artificial inoculation with C. ribicola. In this study, 13 eastern white pine families derived from controlled pollination of selections previously determined to possess putative resistance as well as susceptible selections were inoculated with C. ribicola. Mortality data from inoculation studies show superior survivability in three families with over 60% of seedlings able to survive the 52 week post‐inoculation monitoring period compared to 0–10% survival of the most susceptible families. Primary needles were collected for histological analysis from all inoculated families 4 weeks after inoculation and from selected families 6.5 weeks and 38 weeks after inoculation. Histological observations of infection sites show distinct resistance reactions in the families more likely to survive infection based on mortality data. Analysis of the reactions in susceptible families revealed extensive hyphal colonization of the vascular bundle and adjacent mesophyll cells that appear uninhibited by tree responses. In resistant families, collapsed cells adjacent to infection sites, heavy deposition of phenolic compounds and abnormal cell growth were documented more frequently and appear to play an integral role in the ability of these eastern white pine families to impede growth of C. ribicola in primary needle tissue.     

STUDY ON THE HOST BIOLOGICAL INDUCED RESISTANCE OF BACTERIAL CANKER OF POPLAR

ThefirstrePortabouttheprotectiveeffeetofless-aggrssivestrainswerethatSalamaninoculatedtheless-aggrssivcstrainsofI`tfnchingIobaccoontobaccoandIeaditob-tainpartresistance.ANerthen,thcexistofinducedresistancehavebeenrcPortonseveralkindsofplantssuchasPnIms,(*cstnut.Ma-hl.v.,1tcumis.lIlmus.lI'4'5'7.8.9.l().14.l5.16.I7.l8.1'J2lj.21=4.2s.2f'.=7.2x.3()IThei11ducedresistanceofplantsisassocl-atcdt`,iththeincrcaseofthelc17clofthepllellem*tl1eprocesscsofphellemaredcpcndonthcactivelevcloftheperoxidas…     

外生菌根真菌促进油松人工幼林生长试验

应用从不同林型下分离获得的外生菌根真菌纯培养菌株中的优良菌种,对油松人工林进行菌剂混合接种试验。结果表明:采用外生菌根真菌对油松林接菌,能使土壤微生物种群数量发生变化;接菌后的土壤中的细菌、真菌、放线菌总数比对照有明显的增加,其中真菌增加558.7%。接菌后的油松菌根侵染率为75%,对照为20%;采用外生菌根真菌对油松林接菌,能够提高其抗病力,增强抗旱性,促进林木的生长。对连续2年接种菌剂的油松幼林调查表明,施用菌剂的油松与对照相比,其地径、树高均有显著增加,树高增长46.1%,地径增长41.3%。所以说外生菌根真菌作为一项生物接种技术,对提高油松林的抗病力,增强抗旱性,促进林木的生长具有重要的作用。     

Effects of various densities of Ophiostoma ips inoculations on Pinus sylvestris in north‐western Spain

The aim was to determine the inoculation density above which Scots pine (Pinus sylvestris) is overcome by the blue‐stain fungus Ophiostoma ips that is associated with the bark beetle Ips sexdentatus. In north‐western Spain, stems of 16 Scots pines were inoculated at various densities (0, 400, 800 or 1600 inoculi/m²) along circumferential 100 or 150 cm wide inoculation belts. Each inoculum consisted of a 5 mm diameter cylinder of malt extract agar colonized by the fungus. Three months later, all trees were harvested and trunk resinosis and foliage colour were visually assessed. The percentage of healthy, desiccated, resin soaked, and blue‐stained sapwood, as well as growth productivity indices, were calculated from stem disks cut from within the inoculated zone of each tree. Sapwood‐specific hydraulic conductivity (Ks) of each tree was measured in the middle of the inoculated zone. All parameters of tree vigour changed dramatically to the worse when inoculation densities were above 400 inoculi/m², and foliage changed from green to yellow‐green or yellow when an inoculation density of 800 instead of 400 was used. The percentage loss of sapwood‐specific conductivity (PLC) increased from 30 to 90% and the percentage of healthy, conductive sapwood dropped from 85 to 35% at 800 inoculi/m². No effect of the width of the inoculation belt was observed, and there was no relationship between tree productivity indices and the level of resistance. A non‐linear negative relationship was found between PLC and the percentage of healthy sapwood. It is concluded that tree resistance was overcome and that trees were going to die when the inoculation density was ≥800 inoculi/m².