榆树对榆毛胸萤叶甲的抗虫性研究

通过对自然状态下１９种榆树榆毛胸萤叶甲发生量的调查，以产卵量和１、２龄幼虫发生高峰幼虫量为指标，用模糊聚类分析法将其分为高抗树种、抗性树种、感虫树种和喜食树种４类，其中：（１）高抗树种为椿榆、太行榆、大叶榆和蜀榆；（２）抗性树种为旱榆、黑榆、毛榆、榔榆、琅琊榆、多脉榆、白榆×椿榆、天优２和天优３；（３）感虫树种为白榆、明陵榆、大果榆、美洲榆和红叶明陵榆；（４）喜食树种为多脉×明陵。野外幼树套笼饲养表明，榆毛胸萤叶甲幼虫取食抗性较强树种太行榆、椿榆和黑榆叶子后不能存活，幼虫死亡率均为１００％。     

榆树叶的发生与防治

榆树叶（也叫榆树金花虫）常见的有兰叶、黄叶、紫叶三种。就豫北而言，尤以榆树兰叶危害最重，并常与黄叶混合发生，共同危害。榆树兰叶成虫俗称黄萤，幼虫俗称榆虱，危害榆叶和榆花，使叶子呈网状或穿孔，留下叶柄和叶脉，不久干枯脱落。严重时整树叶子被吃光，致使二次发芽。如连续受害，就会整枝或全株枯死。1生活习性榆树兰叶属完全变态昆虫，1年发生1～2代，以成虫在墙缝、砖摞、玉米秆摞等背风向阳处越冬。翌年5月开始活动，先危害榆树的花心和花瓣，有趋光性和假死性。经补充营养恢复正常活动后，相继交配，5月中旬产卵，卵多产在新…     

榆跳象生物学特性及其防治

榆跳象是榆树的重要食叶害虫之一，甘肃尚未见记载，近年来在张掖地区发生，虫情日趋严重。该虫１年发生１代，以成虫越夏和越冬，成虫一般自叶背取食叶肉，幼虫潜叶为害。天敌有榆跳象羽角姬小蜂（Ｓｙｍｐｉｅｓｉｓｓｐ．）等。成虫发生期根施３％呋喃丹或用２．５％溴氰菊酯２０００倍液喷雾树冠，效果均可达９０％左右。     

孙瑜现场办公治虫

今年5月23日，合浦县东部沿海的沙田、山口、白沙、公馆、闸口等乡镇的红树林遭受广州小斑螟、双纹白草螟和卷叶蛾等害虫的危害，受害面积达3000亩。主要受害树种是白骨壤，危害特征是树叶和新长的嫩芽被害虫啃食，而且害虫是沿着叶片背面的叶脉取食叶肉，而不吃穿上表皮，剩下的上表皮呈半透明膜状，造成受害的叶片发黄枯萎、脱落，从远处看似火烧。     

榆树对榆毛胸萤叶甲的抗虫性研究

通过对自然状态下１９种榆树榆毛胸萤叶甲发生量的调查，以产卵量和１、２龄幼虫发生高峰幼虫量为指标，用模糊聚类分析法将其分为高抗树种、抗性树种、感虫树种和喜食树种４类，其中（１）高抗树种为椿榆、太行榆、大叶榆和蜀榆；（２）抗性树咎为旱榆、黑榆、毛榆榔榆、琅琊榆、多脉榆、白榆×椿榆、天优２和天优３；（３）感虫树种为白榆、明陵榆、大果榆、美洲榆和红叶明陵榆；（４）喜食树种为多脉×明陵。野外幼树套笼饲养表明     

榆掌舟蛾生活史及习性的初步观察

榆掌舟蛾(Phalera fuscescensButler)又叫黄掌舟蛾或举尾毛虫,以幼虫取食榆树叶片,仅留叶脉和叶柄,严重时能将整株叶片吃光。此虫食量大,来势猛,是乳山县榆树上的一种主要害虫。为了保护榆树生长,1984年我们对该虫的生活史、习性进行了初步观察,现报道如下。     

国内外林木抗虫育种现状

国内外林木抗虫育种现状是： ①迄今未选育出可大面积造林抗虫性良种。②抗虫育种研究（包括害虫生物学抗虫性机理，抗虫性影响因子，育种操作等）不断深入与明朗化。③我国林业改良与害虫防治技术水平较高但抗虫育种进展不大。 抗虫育种研究现状是： ①不同树种，不同种源，对不同虫种表现不同，说明从自然群体中选抗虫林木是可能的，同时也是复杂的产对的。②抗虫性的实质是林木在特定环境下以其内外变化主动或被动对入侵害虫一种防卫潜能的高低。③影响抗虫性的因子有寄主--环境（种源）--昆虫三方面，寄主形态与解剖构造（针叶韧度与纤…     

光肩星天牛的危害及其防治

光肩星天牛是检疫性害虫,主要危害杨树、柳树、榆树、沙枣等阔叶树种.光肩星天牛的幼虫寄生在树干上,从树干基部直至树梢都有寄生.幼虫开始在韧皮部和木质部之间取食,受害处流出树液,有木屑和红棕争虫粪排出.随着虫龄的增加,幼虫在边材穿凿横向坑道,坑道坡此靠近,在同一高     

舞毒娥的生物学特性及防治

舞毒蛾是一种杂食性食叶害虫,在河北承德北部山区一年发生一代,以危害阔叶树种为主,也危害针叶树种,主要危害杨树、柳树、桦树、榆树、沙棘等灌木。对云杉和落叶松也有危害,但相对阔叶树种较轻,该种害虫的危害特点是：杂食性强、危害树种广、取食量大、危害周期长、传播速度快。这种害虫危害周期分为发生初期、上升期、猖獗期、下降期,一个危害周期一般长达8年,目前属于上升期,预测2012年为猖獗期。自2008年以来笔者对这种害虫进行了专题研究。     

白榆肃抗1号的组织培养和再生植株

白榆肃抗１号的组织培养和再生植株孙震（河北省林业科学院石家庄０５００６１）白榆材质坚硬，生长迅速，是我国北方地区的优良绿化造林树种。因榆蓝叶甲的猖獗为害，严重影响了白榆的正常生长。河北省林科所从１９８０年开始对抗榆蓝叶甲白榆优良无性系进行选育，经过表...     

淮北相山8个树种叶片的生态解剖特征

对淮北相山杂灌丛和混交林中8个树种叶片的生态解剖特征进行研究.结果表明,优势种叶片解剖可塑性显著大于亚优势种.叶片厚度、维管束厚度、海绵组织厚度、气孔密度、木质部韧皮部厚度比、栅栏组织厚度和栅栏组织海绵组织厚度比(S/P)等性状,在物种或生境之间的变异较大,称为关键解剖性状.与杂灌丛群落的阳生叶相比,混交林叶片表现出阴生特点:表皮及角质层薄,叶片较薄,栅栏组织不发达,S/P较大,输导组织相对不发达.8个树种叶片对其生境表现出多样化的适应方式,大致可分为3类:阳性旱生植物、耐荫性中生植物和阳性中生植物.演替早期植被中优势种多为阳性植物.     

桤木无性系叶片解剖结构特征与其耐旱性的研究

以28个桤木无性系为研究对象,对其叶片的主要解剖构造特征进行观察、测定与比较,并分析它们在控制水分上的能力。结果表明,桤木叶为典型的异面叶,各无性系间叶片结构指标均存在极显著差异,其中角质层厚度变异最大,气孔密度次之,而叶片组织结构紧密度、叶片组织结构疏松度和叶脉突起度等比较稳定。筛选角质层厚度、栅栏组织厚度、栅/海比值、叶脉突起度和气孔长度等5项叶片旱性结构指标,应用隶属函数值法进行综合评判,无性系的耐旱能力大致划分为:耐旱性强(H05、K22、K17、H13、H03),耐旱性较强(H04、K12、K13、K10),耐旱性中等(H09、K04、K32、H06、K21、H02、H07、K07、K28、K02),耐旱性弱(K24、K27、K25、K20、K05、K26、K15、K16、H08)。     

Physiological and biochemical differences among Ulmus minor genotypes showing a gradient of resistance to Dutch elm disease

Dutch elm disease (DED) spread across Europe and North America in the 20th century killing most natural elm populations. Today, breeding programmes aim at identifying, propagating and studying elm clones resistant to DED. Here, we have compared the physiology and biochemistry of six genotypes of Ulmus minor of variable DED resistance. Leaf gas exchange, water potential, stem hydraulic conductivity and biochemical status were studied in 5‐year‐old trees of AB‐AM2.4, M‐DV2.3, M‐DV2 × M‐CC1.5 and M‐DV1 and 6‐year‐old trees of VA‐AP38 and BU‐FL7 before and after inoculation with Ophiostoma novo‐ulmi. Leaf water potential and net photosynthesis rates declined, while the percentage loss of hydraulic conductivity (PLC) increased after the inoculation in susceptible trees. By the 21st day, leaf predawn and midday water potential, stomatal conductance to water vapour and net photosynthesis rates were lower, and PLC was higher in trees of susceptible (S) genotypes inoculated with the pathogen than in control trees inoculated with water, whereas no significant treatment effect was observed on these variables in the resistant (R) genotypes. Fourier transform infrared spectroscopy analyses revealed a different biochemical profile for branches of R and S clones. R clones showed higher absorption peaks that could be assigned to phenolic compounds, saturated hydrocarbons, cellulose and hemicellulose than S clones. The differences were more marked at the end of the experiment than at the beginning, suggesting that R and S clones responded differently to the inevitable wounding from inoculation and repeated sampling over the experimental course. We hypothesize that a weak activation of the defence system in response to experimental wounding can contribute to the susceptibility of some genotypes to O. novo‐ulmi. In turn, the decline in shoot hydraulic conductivity and leaf carbon uptake caused by the infection further exacerbates tree susceptibility to the fungus.     

五种榆树在榆阳区的生长适应性研究

为了丰富榆阳区榆树种类,给当地植树造林、改善生态环境以及城乡绿化提供更多优良榆树种类,从新疆和河南引进了裂叶榆、圆冠榆、大叶垂榆和金叶榆,与榆阳区乡土树种白榆对照进行生长适应研究,结果表明:4种引进榆树均可以成活生长,除白榆之外,裂叶榆和金叶榆能够完成生长、开花、结果及果实成熟等整个生命周期。生长量由大到小依次为裂叶榆、圆冠榆、大叶垂榆和金叶榆。新引进的4种榆树分别作为风沙治理、改善生态环境以及市内观赏景观树种可在榆阳区引种推广应用。     

金叶榆嫁接技术

金叶榆系白榆变种,叶片金黄,色泽艳丽;其枝条萌生力强,枝条密集,耐修剪;对寒冷、干旱气候具有极强的适应性和很强的抗盐碱性,是用于园林、城区道路绿化美化的主要彩叶绿化树。为了满足绿化需要,开展了金叶榆绿化苗嫁接培育,并取得了良好的效果。     

Evaluation of Dutch elm disease susceptibility and pathogenicity of Ophiostoma ulmi using micropropagated elm shoots

Elm (Ulmus sp.) shoots from in vitro micropropagated plants were tested with Ophiostoma ulmi culture filtrates, at different dilutions to determine the susceptibility of different host clones to Dutch elm disease (DED). ‘Commelin’, a susceptible Dutch hybrid, showed a high wilting index but that of American elm was higher. Although U. pumila × japonica (Sapporo gold 2) was the most tolerant to spore inoculation, its wilting index was as high as that of ‘Commelin’. The absorption capacity and wilting index of the elm shoots showed consistent correlation to isolate effectiveness (as determined by inoculation experiments), to production of toxin (cerato-ulmin) and to filtrate dilution. This method could be used to assess the effectiveness of the different O. ulmi isolates and for the detection of elm genotypes that are highly susceptible to Dutch elm disease.     

黑榆不同无性系苗期表型性状及光合特征的差异性比较

为了解黑榆不同无性系的遗传变异情况,以河北省深州市栽培的15个黑榆无性系为材料,对黑榆不同无性系的生长、叶片形态和光合生理指标进行对比分析,结果表明:15个黑榆无性系间苗期生长性状及光合生理等性状指标差异显著,在15个黑榆无性系中,D7的地径最大,为2.33cm;B19平均苗高最大,为2.57m;叶长、叶宽、叶面积在不同无性系间存在显著差异,单叶面积最大相差4.1倍,不同无性系间宽长比在0.58~1.21之间变化,说明黑榆不同无性系间在叶片形态上存在着广泛的遗传变异,而且差异显著。无性系B18、D9的净光合速率最高,分别为23.54μmol/(m2·s)和23.82μmol/(m2·s);无性系D2蒸腾速率最高,为11.18mmol/(m2·s),无性系D4的蒸腾速率最低,为6.71mmol/(m2·s)。结合生长性状分析不同无性系的净光合速率,发现具有较高净光合速率的无性系,并不具有较大生长量,蒸腾速率反而和较大生长量存在显著的负相关。     

Association of Eucalyptus globulus leaf anatomy with susceptibility to Teratosphaeria leaf disease

Resistance of Eucalyptus globulus juvenile foliage to Teratosphaeria leaf disease (TLD) damage has been shown to be under genetic control. Constitutive traits of juvenile leaves such as stomatal density (counted with wax on and with wax removed), total phenolics, total leaf wax, leaf mass per area (LMA) and leaf anatomical features were assessed to determine differences between pairs of resistant and susceptible families. Anatomic features assessed included cuticle, epidermis, palisade spongy mesophyll and total leaf thickness, as well as palisade cell size, shape and intercellular airspace. One interprovenance, one intraprovenance and two within‐family contrasts were used to compare resistant and susceptible pairs of families of Australian origin. The more resistant families had a significantly higher LMA and smaller percentage airspace compared with susceptible families. It is argued that one of the mechanisms by which E. globulus resists TLD involves the closely packed palisade mesophyll cells that increases LMA and reduces airspace, thereby restricting pathogen spread once infection has occurred.     

Pollen morphology and trichome types of Betula spp. in the Hyrcanian forests of northern Iran

Pollen and trichome morphology of the genus Betula were evaluated from three main habitats in Iran using light and electron microscopy.Pollen types were identical and tri-porate;however,in terms of quantitative data,some differences were observed in exine(outside)wall thickness,length of polar axis and length of equatorial axis,possibly due to the environment.Pollen alone is insufficient to separate species of Iranian birch.Investigation of the trichome trait(small hairs or other outgrowths)revealed that birch species in Iran belong to:(1)Betula litwinowii Doluch.according to the low density of trichomes on the adaxial surface of the leaves and the lack of trichomes on the abaxial surface and many trichomes on the petioles;(2)Betula pendula Roth.due to the absence of trichomes on the adaxial surface and the low density of trichomes on the abaxial surface;and,(3)in the adaxial and abaxial surfaces of leaves and petioles,the trichomes had different types of pilose(long,soft hairs),and this strengthens the possibility of a different species or more likely a hybrid of B.pendula.     

四种含笑叶解剖性状与抗旱性的研究

对2年生乐昌含笑、金叶含笑、阔瓣含笑和深山含笑等4种含笑叶片组织解剖性状的测定与盆栽抗旱性观测表明:供试树种间叶解剖性状在叶片厚度、角质层厚度、栅栏组织厚度、海绵组织的厚度、栅栏组织与海绵组织的厚度比、叶片结构紧密度、叶片结构疏松度和气孔密度等指标有显著差异;上表皮和下表皮厚度结构指标差异不显著.叶片厚度、角质层厚度、栅栏组织厚度、栅栏组织与海绵组织厚度的比值、叶片结构紧密度和气孔密度等值越大的含笑,受旱危害愈轻,其抗旱性就越强.叶片厚度、尤其是角质层的厚度和海绵组织厚度是评价供试含笑抗旱性的重要解剖指标.依据叶解剖性状结构指标,并结合盆栽试验旱害观测,供试树种的抗旱性大小为:阔瓣含笑>深山含笑>金叶含笑>乐昌含笑.研究结果与大田容器苗受持续秋旱产生的旱害观测结果吻合,为苏南地区北移引种提供了科学依据.