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Heri Santoso Totok Gunawan Retnadi Heru Jatmiko Witjaksana Darmosarkoro Budiman Minasny 《Precision Agriculture》2011,12(2):233-248
The application of remote sensing technology and precision agriculture in the oil palm industry is in development. This study
investigated the potential of high resolution QuickBird satellite imagery, which has a synoptic overview, for detecting oil
palms infected by basal stem rot disease and for mapping the disease. Basal stem rot disease poses a major threat to the oil
palm industry, especially in Indonesia. It is caused by Ganoderma boninense and the symptoms can be seen on the leaf and basal stem. At present there is no effective control for this disease and early
detection of the infection is essential. A detailed, accurate and rapid method of monitoring the disease is needed urgently.
This study used QuickBird imagery to detect the disease and its spatial pattern. Initially, oil palm and non oil palm object
segmentation based on the red band was used to map the spatial pattern of the disease. Secondly, six vegetation indices derived
from visible and near infrared bands (NIR) were used for to identify palms infected by the disease. Finally, ground truth
from field sampling in four fields with different ages of plant and degrees of infection was used to assess the accuracy of
the remote sensing approach. The results show that image segmentation effectively delineated areas infected by the disease
with a mapping accuracy of 84%. The resulting maps showed two patterns of the disease; a sporadic pattern in fields with older
palms and a dendritic pattern in younger palms with medium to low infection. Ground truth data showed that oil palms infected
by basal stem rot had a higher reflectance in the visible bands and a lower reflectance in the near infrared band. Different
vegetation indices performed differently in each field. The atmospheric resistant vegetation index and green blue normalized
difference vegetation index identified the disease with an accuracy of 67% in a field with 21 year old palms and high infection
rates. In the field of 10 year old palms with medium rates of infection, the simple ratio (NIR/red) was effective with an
accuracy of 62% for identifying the disease. The green blue normalized difference vegetation index was effective in the field
of 10 years old palms with low infection rates with an accuracy of 59%. In the field of 15 and 18 years old palms with low
infection rates, all the indices showed low levels of accuracy for identifying the disease. This study suggests that high
resolution QuickBird imagery offers a quick, detailed and accurate way of estimating the location and extent of basal stem
rot disease infections in oil palm plantations. 相似文献
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小麦黄化型病毒病的研究 总被引:2,自引:0,他引:2
利用蚜虫传播、免疫电泳和超薄切片的电镜观察等方法对小麦田间新出现的四种黄化型病毒病进行了系统研究,确定是由大麦黄矮病毒所致,而不是小麦黄叶病。禾谷缢管蚜需要6小时可完成传毒,平均发病率为85%。大麦黄矮病毒粒子只存在和复制于植物韧皮部组织的筛管和伴胞内,病毒粒子大量聚集在细胞质内并在细胞质内形成“扭结”线状内含体。 相似文献
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[目的]明确宁夏六盘山伏毛铁棒锤根系结构、生长方式及生物碱在组织中的分布。[方法]采用石蜡切片及生物碱定位技术。[结果]伏毛铁棒锤根系由主根、侧根和不定根(块根)组成。根系初生结构正常,次生结构异常。主根的形成层和额外形成层分别产生了异常次生结构中的"U"形次生维管束和三生维管束,且主根的筛管群是由初生韧皮部和形成层分化的小筛管群组成;块根的次生木质部呈"U"形,次生韧皮薄壁细胞占据了块根的绝大部分,且块根的筛管群主要由次生韧皮薄壁细胞分化形成。[结论]主根和块根的形成层组成及活动方式的不同导致了二者异常次生结构的不同。生物碱在主根中主要积累于内侧皮层和束间薄壁细胞,在块根中主要在次生韧皮薄壁细胞和髓中。 相似文献
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伏毛铁棒锤根系异常次生生长及生物碱组化定位 总被引:2,自引:0,他引:2
[目的]明确宁夏六盘山伏毛铁棒锤根系结构、生长方式及生物碱在组织中的分布。[方法]采用石蜡切片及生物碱定位技术。[结果]伏毛铁棒锤根系由主根、侧根和不定根(块根)组成。根系初生结构正常,次生结构异常。主根的形成层和额外形成层产生了异常次生结构中的"U"形次生维管束和三生维管束,且主根的筛管群是由初生韧皮部和形成层分化的小筛管群组成。而块根的次生木质部呈"U"形,次生韧皮薄壁细胞占据了块根的绝大部分,且块根的筛管群主要由次生韧皮薄壁细胞分化形成。[结论]主根和块根的形成层组成及活动方式的不同导致了二者异常次生结构的不同。生物碱在主根中主要积累于内侧皮层和束间薄壁细胞,在块根中主要在次生韧皮薄壁细胞和髓中。 相似文献
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Davis RE Worley JF Whitcomb RF Ishijima T Steere RL 《Science (New York, N.Y.)》1972,176(4034):521-523
Mycoplasma-like bodies with helical filaments were seen by phase contrast microscopy in juice expressed from tissues of plants infected with corn stunt agent. Each filament is bounded by a "unit membrane" and no cell wall, sheath, envelope, or second membrane has yet been discerned by electron microscopy. The association of these filaments with development of disease, their occurrence in phloem cells as seen by both freeze-etching and thin-section electron microscopy, the diagnosis of infection based on their presence in plants without symptoms, and their absence in noninfected corn are consistent with the hypothesis that these unusual filaments are formed by the mycoplasma-like organism presumed to be the corn stunt agent. 相似文献
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20世纪80年代在非洲科特迪瓦发现一种橡胶树割面病害,称为树皮坏死病,后来又称为树干韧皮部坏死病。该病是不可逆的,其最典型症状是接穗和砧木连接处最先出现韧皮部内层组织坏死。调查证明,在10~12龄以下的死皮树中,绝大多数具有树干韧皮部坏死病的典型症状。研究者假定,该病是由环境胁迫(特别是水分缺乏)引起的生理病害,氰化物中毒是韧皮部坏死的直接原因。但是笔者推测,该病由树皮伤口侵入的病原引起。 相似文献
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《Science (New York, N.Y.)》1989,245(4923):1167
In Eliot Marshall's News & Comment article "Fallout from Pacific reaches Congress" (14 July, p. 123), Rongelap Atoll is described as "three-tenths of a square mile of sand and coconut palms." The atoll actually contains about 4 square miles of land surfaces. In addition, the lagoon encompassed by the atoll covers approximately 350 square miles. 相似文献
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作者对70只开放系统内饲养的不同年龄、性别昆明种小鼠作了肠道鞭毛虫区系分布、自然感染状况的观察,共检出8种肠道鞭毛虫.其感染率和肠道分布如下:鼠唇鞭毛虫感染率为80.00%,多见于盲肠、小肠后端;鼠贾第虫感染率为51.43%,多见于小肠前端;鼠六鞭毛虫为68.57%,多见于小肠前端;鼠八鞭毛虫为78.57%,多见于盲肠;人五毛滴虫为88.57%,多见于盲肠、结肠;田鼠四毛滴虫为82.86%,多见于盲肠;微小三毛滴虫为47.14%,多见于盲肠、结肠;鼠三毛滴虫为91.43%,多见于盲肠、结肠及小肠后端。被检70只小鼠均有肠道鞭毛虫感染,其中感染7种肠道鞭毛虫的有9只,占被检总数的12.86%,8种全部感染的有61只,占被检总数的87.14%. 相似文献
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杜仲茎韧皮部超微结构的初步研究 总被引:8,自引:0,他引:8
杜仲(Eucommia ulmoides Oliv.)茎韧皮部组成分子的超微结构与一般双子叶植物的相类似,但其韧皮薄壁组织细胞之间分布着含胶细胞。韧皮薄壁细胞中含有少量橡胶颗粒,伴胞和成熟的筛分子中却未见有分布。橡胶物质在细胞间转移的趋势不明显。因此,我们认为韧皮部含胶细胞内橡胶物质的合成和积累具有相对的独立性。其筛分子质体为S—型。此外,在成熟筛板的筛孔周围都衬有很厚的胼胝质,并为一些电子不透明的P—蛋白质所堵塞,这种现象可能是由于制备样品过程中对韧皮部损伤而引起的损伤反应。 相似文献
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三种松干锈病组织病理学研究 总被引:2,自引:0,他引:2
经过对3种松干锈病的组织解剖研究.发现由Cronartiumflaccidum和C.ribicola引起的松疱锈病组织病变发生在寄主的皮层、韧皮部.菌丝也可沿木射线薄壁细胞进入木质部、但木质部薄壁细胞未发生增生。管胞的长宽和木质部木射线高度与正常组织相比.差异不显著。由C.quercuum引起的松瘤锈病组织病变.主要发生在木质部.也可发生在寄主皮层、韧皮部。与健康组织相比.其管胞的长、宽和木射线高度均差异显著。兴凯湖松健康组织和由C.quercuum引起的寄主瘤部增生组织的年轮生长模型分别为Y_健=61.9714(1-e ̄(-0.0155x)) ̄1.061和Y_瘤=254.2977(1-e ̄(-0.0102x)) ̄1.0708. 相似文献
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韧皮部同化物和水分运输相关关系的示踪动力学研究 总被引:1,自引:0,他引:1
将14C-糖和3H-水分别引入到棉茎韧皮部和木质部,结果表明,同化物在韧皮部中运输时,必须有木质部水分的参与,和木质部分离的韧皮部不能单独履行运输同化物的功能;同化物在韧皮部中以液流形式运输,液流中的水主要来自木质部。同化物向韧皮部的装载,是不伴随水的主动装载过程。韧皮部同化物运输和木质部水分密切相关。 相似文献
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Transmission studies carried out in the laboratory incriminated Phlebotomus vexator occidentis as a vector of a species of trypanosome that infects Bufo boreas halophilus. Toads free of parasites contracted the trypanosome after eating infected flies and after intraperitoneal inoculation of flagellates cultured from the hindgut of flies that had fed on infected toads. Discovery of this vectorhost-parasite system in the Americas, and the localization of promastigote flagellates (leptomonads) in the hindgut of the vector, should assist in clarifying interpretative problems associated with infection of wild-caught flies in studies on leishmaniasis in the Americas and elsewhere. 相似文献
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Chen LQ Qu XQ Hou BH Sosso D Osorio S Fernie AR Frommer WB 《Science (New York, N.Y.)》2012,335(6065):207-211
Plants transport fixed carbon predominantly as sucrose, which is produced in mesophyll cells and imported into phloem cells for translocation throughout the plant. It is not known how sucrose migrates from sites of synthesis in the mesophyll to the phloem, or which cells mediate efflux into the apoplasm as a prerequisite for phloem loading by the SUT sucrose-H(+) (proton) cotransporters. Using optical sucrose sensors, we identified a subfamily of SWEET sucrose efflux transporters. AtSWEET11 and 12 localize to the plasma membrane of the phloem. Mutant plants carrying insertions in AtSWEET11 and 12 are defective in phloem loading, thus revealing a two-step mechanism of SWEET-mediated export from parenchyma cells feeding H(+)-coupled import into the sieve element-companion cell complex. We discuss how restriction of intercellular transport to the interface of adjacent phloem cells may be an effective mechanism to limit the availability of photosynthetic carbon in the leaf apoplasm in order to prevent pathogen infections. 相似文献
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天葵"块根"是由主根及下胚轴共同膨大形成,天葵药材的形态本质应为肉质直根。天葵肉质直根的增粗主要原因是由于木薄壁细胞产生三生形成层,形成大量三生维管束;以及次生韧皮部和次生木质部中薄壁细胞的不断增加。 相似文献
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采用双标记法,将14C-糖和3H-水分别引入到棉茎韧皮部和木质部不同处理中,再用示踪动力学分析法对数据进行测定、计算和分析。结果表明,同化物在韧皮部中运输时,必须有木质部水的参与,和木质部分离的韧皮部不能单独运输同化物,仅存在同化物和水分的扩散迁移。同化物在韧皮部中以液流形式运输,液流中的水主要来自木质部。同化物向韧皮部的装载,是不伴随水的主动装载过程。同化物在韧皮部中的分布,存在着一定的浓度梯度,是推动同化物由源到库运输的动力来源之一,这与压力流学说基本一致。 相似文献
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采用酶细胞化学技术对7个甘蔗种和品种进行研究。甘蔗茎韧皮部细胞 ATP 酶活性定位于筛管、伴胞质膜、伴胞核、小囊泡、充分发育的液泡膜和 P—蛋白上。野生种和栽培种茎韧皮部细胞 ATP 酶活性较高,而生产品种则较低。认为甘蔗茎韧皮部 ATP 酶活性与糖分的运输和抗性等有关。茎韧皮运输中,可能有 P—蛋白和 ATP 酶主动参与。 相似文献