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Eurasian Soil Science - The data of experimental studies on the postpyrogenic dynamics of the litter in mountain taiga cedar (Pinus sibirica), pine (Pinus sylvestris) and subtaiga forest-steppe... 相似文献
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Cryphonectriaceae species cause serious canker diseases on chestnut, oak and eucalypt trees. Recently, canker symptoms with typical orange fruiting bodies were observed on Chinese chestnut and oak trees in Hebei, Hubei, Shaanxi and Shandong Provinces in China. In the present study, isolates of these fungi were identified based on phylogenetic and morphological evidence, and their pathogenicities were tested on detached chestnut (Castanea mollissima) branches. DNA sequence comparisons of the internal transcribed spacer (ITS) regions and two regions of β-tubulin (TUB1/TUB2) indicate that these isolates represent five species in the Cryphonectriaceae, viz. Cryphonectria japonica, Cryphonectria parasitica, Aurantiosacculus castaneae sp. nov., Cryphonectria neoparasitica sp. nov. and Endothia chinensis sp. nov. The sexual morph of Aurantiosacculus is discovered for the first time and can be distinguished from the other genera in Cryphonectriaceae by dark brown ascospores and tubiform appendages at both ends. Cryphonectria neoparasitica sp. nov. is different from the other Cryphonectria species by its aseptate ascospores. Endothia chinensis sp. nov. is the sole species in Endothia infecting the host genus Castanea. Additionally, it is much smaller than E. gyrosa and narrower than E. singularis in ascospores. The inoculation results showed that these five Cryphonectriaceae fungi isolated from chestnut or oak are all pathogenic to tested chestnut branches. Cryphonectria parasitica appears to be the most aggressive fungus, followed by C. neoparasitica sp. nov., C. japonica, E. chinensis sp. nov. and A. castaneae sp. nov. 相似文献
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The hemlock looper, Lambdina fiscellaria (Guenée), is a serious forest pest in North America with three subspecies that vary in their geographical range and larval host preferences. Both broadleaved and coniferous trees are infested, though the largest impacts are on coniferous forestry where trees can be completely defoliated and killed. The pest was identified as a potential threat to forestry on the island of Ireland during a horizon‐scanning exercise to identify pests of Picea sitchensis (Bong.) Carr. (Sitka spruce) and was subject to a rapid pest risk analysis (PRA). Though judged to be unlikely, pathways identified were uncontrolled wood commodities and mosses and lichens harvested from forests in North America and exported for use in ornamental displays. Lambdina fiscellaria is found in a range of climate types, and is likely to be able to complete its lifecycle in the Irish climate – although there is uncertainty concerning its ability to adapt to European trees. Lambdina fiscellaria has only a limited capacity for spread, as virgin females are burdened by their eggs and are poor fliers. This was judged to reduce potential impacts in the PRA area – as the slow rate of spread would provide time to develop monitoring and control methods well ahead of the pest reaching its maximum extent on the island of Ireland. The pest still poses a considerable risk to coniferous forestry not only on the island of Ireland but across the EPPO region where climate is suitable for the pest to establish. Regulation and implementation of phytosanitary measures prevent introduction of the pest should be considered. 相似文献
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Adams Alison B. Pontius Jennifer Galford Gillian Gudex-Cross David 《Landscape Ecology》2019,34(10):2401-2419
Landscape Ecology - Understanding how the Northern Forest landscape has changed and is likely to change, both in terms of forest extent and forest configuration, has important implications for... 相似文献
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Sheikh Muhammad Masum Mohammad Amzad Hossain Hikaru Akamine Jun‐Ichi Sakagami Takahiro Ishii Ichiro Nakamura Md. Asaduzzaman Prasanta Chitta Bhowmik 《Weed Biology and Management》2019,19(2):39-50
This study aimed to identify the potential allelopathic indigenous rice (Oryza sativa L. ssp. indica) varieties from Bangladesh using a performance study in a weed‐infested field and to assess the extent of allelopathic interference relative to resource competition in a glasshouse experiment. Six varieties – namely, “Boterswar,” “Goria,” “Biron” and “Kartiksail” as the most allelopathic, “Hashikolmi” as weakly allelopathic and “Holoi” as nonallelopathic – were raised following a nonweed control method. The infestation levels of weed species were calculated using Simpson's Diversity Index (SDI), which ranged from 0.2 to 0.56. However, a significant correlation coefficient (0.87, P < 0.001) was obtained from these field data compared with the root inhibition percentage from the laboratory bioassay, and the “Boterswar” variety was the most allelopathic. The interactions between the allelopathic variety “Boterswar,” weakly allelopathic variety “Hashikolmi” and Echinochloa oryzicola via a target (rice)‐adjacent (E. oryzicola) cogrowth culture were determined in a hydroponic arrangement. The relative competitive intensity (RCI) and the relative neighbor effect (RNE) values showed that the crop–weed interaction was facilitation for “Boterswar” and competition for “Hashikolmi” and E. oryzicola in rice/E. oryzicola cogrowth cultures. The allelopathic effects of “Boterswar” were much higher than the resource competition in rice/E. oryzicola cogrowth cultures. The converse was observed for “Hashikolmi.” Moreover, the mineral content of E. oryzicola was severely affected by “Boterswar”/E. oryzicola cogrowth cultures’ exudate solution. Therefore, the allelopathic potential of “Boterswar” variety might be useful for developing the weed‐suppressing capacity of rice, which will likely have a significant influence on paddy weed control. 相似文献