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51.
吊丝单竹笋期叶片特性研究 总被引:4,自引:0,他引:4
对3种不同年龄的吊丝单竹株在不同发笋时期、不同竹冠部位的叶片比叶重、光合、呼吸性状及N、P、K含量等进行测定,结果表明:吊丝单竹在不同发笋时期、不同竹冠部位各项指标均有较大差异。比叶重发笋盛期高于初期和末期,随着竹株年龄增大而减小,随着竹冠的升高而增大;净光合速率盛期高于初期,光呼吸速率和暗呼吸速率则初期高于盛期,并且不同竹龄、不同竹冠部位之间均表现出较大的差异;N、P、K含量由发笋初期至盛期逐渐减小,N含量以1a>2a>3a,以竹冠中部最高,P、K含量则随着竹冠的升高而减小,随着竹株年龄的增大而增大。这为经营管理吊丝单竹林提供科学依据。 相似文献
52.
Expansion of bamboo forests caused by reduced bamboo-shoot harvest under different natural and artificial conditions 总被引:3,自引:0,他引:3
To elucidate the expansion of bamboo (Phyllostachys pubescens Mazel ex Houzeau de Lehaie) forests, we used multiple linear regression analysis and determined whether there were site differences
for data obtained in Hirasawa, Otaki-machi, Chiba Prefecture, and Kofuki, Takehara City, Hiroshima Prefecture, Japan. Vegetation
maps from 1984 and 2001 for Hirasawa, and from 1986, 1996, 2000, and 2006 for Kofuki, were compared, and the annual expansion
rate of each P. pubescens forest was calculated. We evaluated nine indices, including original bamboo forest area, neighbouring vegetation, slope inclination
and aspect, distance from roads, and shipment of bamboo shoots. Shipment of bamboo shoots was a positive factor for P. pubescens forest expansion, whereas the proportion of adjacent short vegetation, northness (the cosine of slope aspect), and area negatively
affected the expansion in Hirasawa (R
2 = 0.683). On the other hand, distance from roads and eastness (the sine of slope aspect) positively affected expansion, while
slope inclination was a negative factor in Kofuki (R
2 = 0.942). We calculated that P. pubescens forests expanded at about 2% per year in regions of reduced shipments of bamboo-shoot harvest. We showed that not only natural
conditions but also management factors affect P. pubescens forest expansion. Regional differences in natural and anthropogenic effects on expansion were also found. 相似文献
53.
Eiji Tanaka Kiminori Shimizu Yumi Imanishi Fumitoshi Yasuda Chihiro Tanaka 《Mycoscience》2008,49(5):329-333
A basidiomycetous anamorphic yeast-like fungus, isolated from new bamboo shoots collected in Japan, was assigned to Meira argovae by comparison of conidial morphology, physiological characteristics, rDNA sequences, and DNA-DNA relatedness with the ex-type
strains of Meira species. This is the first record of the finding of M. argovae from other than mite cadavers and in regions other than Israel. Phylogenetic analysis based on the D1-D2 domain demonstrated
that Meira species and teleomorphic Dicellomyces species, which include a bamboo leaf parasite, D. gloeosporus, formed sister clades. 相似文献
54.
慈竹叶精油化学成分研究 总被引:5,自引:0,他引:5
首次报道了贵州省慈竹叶精油化学成分的研究。竹叶精油提取率为 0 2 %。用气相色谱 -质谱 (GC/MS)联用仪分离出 87个化合物 ,确认了其中 2 4个 ,主要芳香物质为C5~C8的含氧化合物。 相似文献
55.
Effects of flooding regime and woody bamboos on tree community dynamics in a section of tropical semideciduous forest in South-Eastern Brazil 总被引:1,自引:0,他引:1
Guilherme Frederico A.G. Oliveira-Filho Ary T. Appolinário Vivette Bearzoti Eduardo 《Plant Ecology》2004,174(1):19-36
The influence of a population of the understorey woody bamboo Merostachys riedeliana and different flooding regimes on tree community dynamics in a section of tropical semideciduous forest in South-Eastern
Brazil was examined. A forest section with an area of 1.6 ha composed of 71 adjacent plots was located on a slope ending at
the river margin. The section was divided into five topographical sectors according to the mean duration of river floods.
In 1991 and 1998 all trees with a diameter at the base of the trunk ≥ 5 cm were measured, identified and tagged, and all live
bamboo culms were counted. Annualised estimates of the rates of tree mortality and recruitment, gain and loss of tree basal
area, and change in bamboo density were calculated for each of the 71 plots and five topographical sectors as well as for
diameter classes and tree species. To segregate patterns arising from spatially autocorrelated events, geostatistical analyses
were used prior to statistical comparisons and correlations. In general, mortality rates were not compensated by recruitment
rates but there was a net increase in basal area in all sectors, suggesting that the tree community as a whole was in a building
phase. Tree community dynamics of the point bar forest (Depression and Levée sectors) differed from that of the upland forest
(Ridgetop, Middle Slope and Lower Slope sectors) in the extremely high rates of gain in basal area. The predominant and specialised
species, Inga vera and Salix humboldtiana, are probably favoured by relaxed competition in an environment stressed by long-lasting floods. In the upland forest, mortality
rates were highest at the Middle Slope, particularly for smaller trees, while recruitment rates were lowest. As bamboo clumps
were concentrated in this sector, the locally higher instability in the tree community probably resulted from the direct interference
of bamboos. The density of bamboo culms in the upland forest was negatively correlated with the rates of tree recruitment
and gain in basal area, and positively correlated with tree mortality rates. Bamboos therefore seemed to restrict the recruitment,
growth and survival of trees.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
56.
间伐是竹林复壮更新的有效手段之一.以陕西佛坪国家自然保护区为研究区域,对大熊猫(Ailuropoda melanoleuca)冬季栖息地非主要采食区域竹林老龄化严重且密度过大的巴山木竹(Bashania fargesii)林进行为期3年(2017至2019年)的带状间伐样方监测,研究间伐对竹林复壮更新以及大熊猫觅食选择... 相似文献
57.
棕胸竹鸡觅食行为的观察 总被引:16,自引:3,他引:13
对笼养条件下棕胸竹鸡(Bambusicola fytchii fytchii)每日的觅食节律的时间、频次、求偶取食行为和社群等级之间的关系进行了观察。结果表明:影响棕胸竹鸡觅食行为的主要因素是一天中它在地面上活动、静栖、游走及饮水等项行为所占时间的长短。影响求偶取食行为的主要因素是它在地面上活动的总时间和理羽、攻击及其它的求偶活动所占的时间多少。社群等级对棕胸竹鸡的觅食行为有一定的影响,但不甚显著。 相似文献
58.
59.
60.
I-Hsuan Chen Jui-En Chang Chen-Yu Wu Ying-Ping Huang Yau-Huei Hsu Ching-Hsiu Tsai 《Molecular Plant Pathology》2019,20(5):673-684
One up-regulated host gene identified previously was found involved in the infection process of Bamboo mosaic virus (BaMV), a single-stranded positive-sense RNA virus. The full length cDNA of this gene was cloned by 5′ and 3′-rapid amplification of cDNA ends and found to encode a polypeptide containing a conserved really interesting new gene (RING) domain and a transmembrane domain. The gene might function as an ubiquitin E3 ligase. We designated this protein in Nicotiana benthamiana as ubiquitin E3 ligase containing RING domain 1 (NbUbE3R1). Further characterization by using Tobacco rattle virus-based virus-induced gene silencing (loss-of-function) revealed that increased BaMV accumulation was in both knockdown plants and protoplasts. The gene might have a defensive role in the replication step of BaMV infection. To further inspect the functional role of NbUbE3R1 in BaMV accumulation, NbUbE3R1 was expressed in N. benthamiana plants. The wild-type NbUbE3R1-orange fluorescent protein (NbUbE3R1-OFP), NbUbE3R1/△TM-OFP (removal of the transmembrane domain) and NbUbE3R1/mRING-OFP (mutation at the RING domain, the E2 interaction site) were transiently expressed in plants. NbUbE3R1 and its derivatives all functioned in restricting the accumulation of BaMV. The common feature of these constructs was the intact substrate-interacting domain. Yeast two-hybrid and co-immunoprecipitation experiments used to determine the possible viral-encoded substrate of NbUbE3R1 revealed the replicase of BaMV as the possible substrate. In conclusion, we identified an up-regulated gene, NbUbE3R1 that plays a role in BaMV replication. 相似文献