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重大园林植物病害及其研究进展 总被引：2，自引：0，他引：2
系统地介绍了国内外重大的园林植物病害:松材线虫病、榆树荷兰病、五针松疱锈病、观赏植物冠瘿病、香石竹尖镰孢枯萎病和菊花叶枯线虫病, 综述了这些病害的国内外研究进展。 相似文献
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菊花叶枯线虫痫是菊科花卉植物的主要叶郜病害。菊叶受害后，叶色变淡，侵入点先变褐色，并出现淡黄色甚争黄褐色斑，造成叶片卷缩、凋萎，并沿茎干下垂；菊花受害严重时，也会造成花器受损，花的发育受抑制，花芽、花蕾干卡占或退化，植株外型萎缩。另外，此病害还危害长春花、草莓、蔬菜、杂草等40属200多种植物。 相似文献
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一、菊花黑斑病 (被害与诊断) 叶被害。起初,出现不规则的褐色的小斑点,但逐渐便扩大成为圆形、椭圆形、不正形等的褐色乃至黑褐色的病斑。病斑的形状,因品种不同而有差异。另外,受叶脉限制,有时成扇形,有时也呈现微小斑点汇合在一起。当大量病斑出现时,叶翘曲,而且病斑周围发黄,不久便枯死,并从下部的叶 相似文献
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菊花褐斑病(Septoria ChrysanthemellaSacc)是菊花的一种重要病害。叶片初发病时出现黄褐色的小点,逐渐扩大成圆形或不规则的病斑,边缘黑褐,中心灰黑色,上生小黑粒。严重时病斑相连成片,使整个叶片焦黑而脱落,致使菊花有花无叶,既有碍观赏,又影响生长、开花。华南地区气候温暖,菊花褐斑病几乎终年发生。病菌孢子借风力,雨水等传播。在 相似文献
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尾叶桉枯梢病的病因有很多，病因不同，采取的防治方法也不同。土壤本身缺乏各种微量元素致使尾叶桉产生枯梢病，通过补充铜、钼、锌等各种微量元素，从而有效地防治了尾叶桉枯梢病。 相似文献
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An avirulent isolate (C14‐5) of the pinewood nematode, Bursaphelenchus xylophilus, was inoculated onto 45 seedlings of the susceptible host Japanese black pine (Pinus thunbergii) and its viability was investigated. The nematode survived inside host seedlings for approximately 7 months even when the host seemed to overcome the infection based on lack of foliar wilting and the observation of normal oleoresin flow. 相似文献
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Sharon E. Reed Sylvia Greifenhagen Qing Yu Adam Hoke David J. Burke Lynn K. Carta Zafar A. Handoo Mihail R. Kantor Jennifer Koch 《Forest Pathology》2020,50(3)
A foliar nematode, Litylenchus crenatae ssp. mccannii, is associated with beech leaf disease (BLD) symptoms. Information about the types of tissues parasitized and how nematode populations fluctuate in these tissues over time is needed to improve surveys as well as understand the nematodes role in BLD. During this study, the nematode was detected throughout the known range of BLD by researchers at both Canadian and US institutions using a modified pan method to extract nematodes. Monthly collections of symptomatic and asymptomatic leaves during the growing season (May–October), and leaves and buds between growing seasons (November–March), revealed that nematodes were present in all tissue types. Progressively larger numbers of nematodes were detected in symptomatic leaves from Ohio and Ontario, with the greatest detections at the end of the growing season. Smaller numbers of nematodes were detected in asymptomatic leaves from BLD‐infected trees, typically at the end of the growing season. The nematode was detected overwintering in buds and detached leaves. The discovery of small numbers of nematodes in detached leaves at one location before BLD was detected indicates that nematodes may have been present before disease symptoms were expressed. Other nematodes, Plectus and Aphelenchoides spp., were infrequently detected in small numbers. Our findings support the involvement of the nematode in BLD and indicate that symptoms develop only when certain requirements, such as infection of buds, are met. We also found that the nematode can be reliably detected in buds and leaves using the modified pan extraction method. 相似文献
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Four Acacia species were tested for their susceptibility to the root-knot nematode, Meloidogyne javanica, commonly found in
sahelian areas. Faidherbia albida and Acacia senegal were resistant to this nematode. On the contrary, A. raddiana, A. nilotica
and A. mangium were susceptible. Among these three species, the growth of A. nilotica and A. mangium was inhibited by M. javanica
but A. raddiana was tolerant. The rhizobial symbiosis with F. albida and A. senegal was stimulated by the nematode. The population
build-up of the root-knot nematode induced by tree species in agroforestry systems is discussed.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
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Gustavo Balmelli Sofía Simeto Nora Altier Virginia Marroni Julio J. Diez 《New Forests》2013,44(2):249-263
Eucalyptus globulus is the most important forest species in Uruguay, with more than 250,000 ha of commercial plantations. Despite its high susceptibility to diseases, production losses caused by foliar diseases have not been properly quantified in this country. This study analyzes the effects of foliar damage on growth and survival using data from a progeny test of E. globulus naturally infected by Teratosphaeria leaf disease and eucalypt rust (Puccinia psidii). The severity of leaf spots and defoliation were quantified 8 months after planting and tree growth and mortality were evaluated 2, 4 and 6 years later. The trial had a high incidence of foliar damage, with a mean leaf spot severity of 28.7% and a mean defoliation of 37%. The greatest impact of foliar damage, both on growth rate and mortality, occurred in the first 2 years after damage was assessed. During this period, leaf spot severity less than 40% and defoliation below 50% did not affect growth, while survival was affected when leaf damage was 70% or greater. By the sixth year both stem growth and survival were affected by severe foliar damage (spotting or defoliation of 80% or more), with a loss of up to 25% in diameter and an accumulated mortality over 70%. It has been established for the first time that under the intensive Uruguayan productive conditions, E. globulus trees can tolerate a relatively high degree of leaf spotting or defoliation but severe foliar damage in the first months can cause considerable production losses, putting at risk the economical viability of this species. 相似文献
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Takefumi Ikeda 《Journal of Forest Research》1996,1(4):223-226
The effect of water-stress conditioning on water relations and histological features ofPinus thunbergii Parl. inoculated with avirulent isolate ofBursaphelenchus xylophilus (Steiner and Buhrer) Nickle, pine wood nematode, were investigated. Pines were kept under 8 days cycle of severe water stress.
One-half of the water-stressed pines died as a result of infection by avirulent pine wood nematode and water stress tended
to induce increased susceptibility and/or decreased resistance of pines to avirulent pine wood nematode. In dead pines, the
water conducting function of xylem was lost, and all of the parenchyma cells died. In surviving pines, the xylem hydraulic
conductivity and the xylem water content were significantly reduced (12 to 23% and 77 to 83%, respectively) compared to controls.
Safranin dye perfusion of excised axis stem segments indicated that the water conductance was limited to the very narrow peripheral
area of xylem. Embolism caused by cavitation in the tracheids occurred in the central part of xylem and in that dysfunctional
region of the xylem the axial parenchyma cells surrounding the epithelial cells, and ray parenchyma cells partly degenerated
but the epithelial cells survived. The disruption of tracheid shape observed in surviving pines indicates that avirulent pine
wood nematode temporarily disturbed cell division of the cambium. Considering the differences in responses between dead pines
and surviving pines after inoculation with avirulent pine wood nematode, the death of water-stressed pines apparently resulted
from death of cells, in particular the vascular cambium and the loss of xylem hydraulic function by cavitation. 相似文献
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用含不同浓度的NAA、6-BA的培养基对15个地被菊品种的叶片进行快速繁殖研究,筛选出地被菊叶片诱导和分化培养基为MS+6-BA 2.0 mg.L-1+NAA 0.5 mg.L-1;最佳增殖培养基是1/2MS;用含不同浓度的NAA对地被菊品种的试管苗进行生根研究,筛选出1/2MS是地被菊的生根培养基。即增殖培养基和生根培养基都用1/2MS,简化了培养基,且长出的幼苗茎粗状、叶片大、叶色浓绿、生长快,增殖系数较高。 相似文献