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191.
毛竹林节肢动物群落的组成与结构 总被引:16,自引:3,他引:16
通过对福建三明和沙县23块毛竹林试验标准地节肢动物群落1a的系统调查,结果表明:竹冠层节肢动物隶属于3纲、21目、124科、332种,林下层节肢动物隶属于3纲、22目、130科、349种。竹冠层和林下层类群分别有92.77%和94.54%的物种为稀有种或偶见种,林下层类群种-丰盛度关系符合对数正态分布。二类群目或功能集团的科、物种的数量分布相近,个体数量分布差异大。竹冠层类群以蜱螨目和同翅目为主,林下层类群以蜘蛛目、膜翅目、同翅目和双翅目为主。前者的科、物种以及个体数的益害比分别为1∶1.18、1∶0.83和1∶4.62,后者为1∶0.91、1∶0.85和1∶0.55。竹冠层类群的物种多样性和均匀度均显著低于林下层类群,植食性集团多样性在林下层类群各功能集团中最高,在竹冠层类群中则最低。群落和功能集团各参数对二类群多样性的影响均以相应类群总体的均匀度最大,功能集团因子中均以相应类群蜘蛛类的均匀度最大。人为排除群落优势种后,二类群的多样性均显著增加,但林下层类群增加的幅度显著低于竹冠层类群。植食性和中性集团作为空间食物种类资源能显著促进群落容纳较多天敌物种,天敌对二集团的空间数量跟随效应强,二集团与天敌的多样性之间相互促进。 相似文献
192.
The butenolide, 3-methyl-2H-furo[2, 3-c]pyran-2-one, is an highly active compound isolated from plant-derived smoke. This compound is known to stimulate seed germination in a wide range of plants akin to smoke or aqueous extracts of smoke. The present study attempted to elucidate the role of the butenolide in overcoming detrimental effects of low and high temperatures on tomato seed germination and seedling growth. The germination percentage followed a parabolic curve for temperatures ranging from 10 to 40°C, with 25°C being the optimum for all treatments. Control seeds showed radicle emergence at two extreme temperatures (10 and 40°C) and seedlings failed to develop further, even upon prolonged incubation. By comparison the butenolide-treated seeds grew into phenotypically normal seedlings at these non-optimum temperatures. The smoke–water-treated seeds had an intermediate response as only a fraction of germinated seed developed into normal seedlings. Seedling vigour indices as well as seedling weight were significantly higher (p ≤ 0.05) for butenolide-treated seeds at all temperatures. Furthermore, seedlings developed in the presence of the butenolide had about a 1:1 correspondence between root and shoot length. Butenolide-treated seeds grew better than the control seeds in the temperature shift experiments. A gradual decline in the vigour index values was recorded with an increased duration of incubation at the extreme temperatures. Results of the present study are very important from an horticultural point of view as they indicate the potential use of the butenolide compound in restoring normal seed germination and seedling establishment in tomato below and above optimum temperatures. 相似文献
193.
194.
Daxu Li Jie Zhang Jian Zhao Yi Zhang Fei Chen Jingqiu Zhu Shujun Liu Zhirong Yang 《Plant Cell, Tissue and Organ Culture》2006,84(3):285-292
The mature seeds, mesocotyls, and young leaf tips of Elymus sibiricus L. cv. ‘chuancao No. 2’ were cultured on Murashige and Skoog (MS) medium supplemented with 5.0 mg/L 2,4-dichlorophenoxyacetic acid (2,4-d) and 0.05 mg/L kinetin in the dark at 26°C, the calluses were produced. The rate of callus regeneration depended on the explants
source and plant growth regulators. Plants regenerated from whitish-yellow-coloured compact nodular callus formed after subculturing
for 8 weeks. Higher frequency (54%) of shoot differentiation was obtained from the embryo tissues of mature seed than from
either mesocotyls (24%) or young leaf tip tissues (6%) when these calluses from different types of explants were cultured
on plant regeneration medium containing half strength MS salts supplemented with 0.1 mg/L kinetin, 1.5 mg/L 2,4-D and 20 g/L sucrose. The green plants were rooted within 6 weeks in the root regeneration medium, and over 97% of these soil-established
plants were obtained in the greenhouse when potted in a sand and peat mixture medium. 相似文献
196.
Yoonkyung Park Baik Hwang Byoungsik Pyo Hyeonsook Cheong 《Biotechnology and Bioprocess Engineering》1997,2(1):15-18
We intended to examine the expression of the T-cell growth factor (human interleukin-2) so that a binary vector, pSSK-1, carrying
the IL-2 gene was constructed and transferred intoA. tumefaciens for the purpose of the transformation of the potato (Solanum tuberosum cv. Superior). All of theAgrobacterium-infected potato explants were regenerated to shoots in modified MS medium and 81% of them rooted on the medium containing
kanamycin (200 mg/L). Southern and Northern analysis were performed to verify the transformation events. EL-ISA test indicated
that IL-2 protein was produced from IL-2-transformed potatoes. These results suggested expression and production of the IL-2
protein from the transgenic potato. 相似文献
197.
Biao Gong Cunjia Zhang Xiu Li Dan WenShuoshuo Wang Qinghua Shi Xiufeng Wang 《Biochemical and biophysical research communications》2014
Soil salinity and alkalinity are common constraints to crop productivity in low rainfall regions of the world. However, the physiological difference of plant response to these two stresses was short of deep investigation. This study has identified a set of differentially expressed proteins of tomato root exploring to NaCl and NaHCO3 stress by iTRAQ (isobaric tags for relative and absolute quantitation) assay. A total of 313 proteins responsive to NaCl and NaHCO3 were observed. Among these proteins, 70 and 114 proteins were up-regulated by salt and alkali stress, respectively. While down-regulated proteins were 80 in salt treatment and 83 in alkali treatment. Only 39 up-regulated proteins and 30 down-regulated proteins were shared by salt and alkali stresses. The majority of the down-regulated proteins accounted for metabolism and energy conversion, and the up-regulated proteins were involved in signaling or transport. Compared with salt stress, alkali stress down-regulated proteins related with the respiratory metabolism, fatty acid oxidative metabolism and nitrogenous metabolism of tomato roots, and up-regulated protein with the reactive oxygen species (ROS) scavenging and ion transport. This study provides a novel insight into tomato roots response to salt and alkali stress at a large translation level. 相似文献
198.
Genetic mapping of ripening and ethylene-related loci in tomato 总被引:5,自引:0,他引:5
J. Giovannoni H. Yen B. Shelton S. Miller J. Vrebalov P. Kannan D. Tieman R. Hackett D. Grierson H. Klee 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1999,98(6-7):1005-1013
The regulation of tomato fruit development and ripening is influenced by a large number of loci as demonstrated by the number
of existing non-allelic fruit development mutations and a multitude of genes showing ripening-related expression patterns.
Furthermore, analysis of transgenic and naturally occurring tomato mutants confirms the pivotal role of the gaseous hormone
ethylene in the regulation of climacteric ripening. Here we report RFLP mapping of 32 independent tomato loci corresponding
to genes known or hypothesized to influence fruit ripening and/or ethylene response. Mapped ethylene-response sequences fall
into the categories of genes involved in either hormone biosynthesis or perception, while additional ripening-related genes
include those involved in cell-wall metabolism and pigment biosynthesis. The placement of ripening and ethylene-response loci
on the tomato RFLP map will facilitate both the identification and exclusion of candidate gene sequences corresponding to
identified single gene and quantitative trait loci contributing to fruit development and ethylene response.
Received: 26 October 1998 / Accepted: 13 November 1998 相似文献
199.
从菊花花叶病标样中分离到一球形病毒分离物 ,直径 2 5~ 2 9nm ,与TAV抗血清反应呈阳性。根据英国报道的番茄不孕病毒 (TAV En)CP基因序列 ,设计合成一对引物 ,对该病毒RNA进行RT PCR扩增 ,得到与预期大小相符的特异扩增带。将其克隆到 pGEM Teasy中 ,经酶切和序列分析表明所克隆的是TAVCP基因 ,与已知的 6个株系相应序列同源性均在 96 .4%以上 相似文献
200.
【背景】番茄黄化曲叶病毒(TYLCV)是由媒介昆虫烟粉虱传播的一种双生病毒,对蔬菜及烟草等经济作物造成严重危害。前人资料表明,该病毒于2006年传人我国南方地区,2007年传人山东省,2008年后在山东各地逐渐蔓延扩散。【方法】为了考证TYLcV传人山东省的时间,本研究利用mtCOI基因对于2005和2006年7—8月份在山东省不同地区作物上共采集的15份烟粉虱样品进行了生物型鉴定,并进一步检测了烟粉虱携带TYLCV情况,同时对PCR扩增产物进行了测序分析。【结果】2005年的4份样品烟粉虱生物型均为B型,均不携带TYLCV。2006年的11份烟粉虱样品为B型与Q型混合样品,其中,2份烟粉虱样品检测到TYLCV,进一步证实该病毒为TYLCV。【结论与意义】本研究首次证实了TYLCV早在2006年就已经传入山东省。研究结果不仅对于防控该病毒具有重要指导意义,而且对于其入侵生物学研究也具有重要参考价值。 相似文献