Assessment of Rhizospheric Microorganisms of Transgenic Populus tomentosa with Cowpea Trypsin Inhibitor (CpTI) Gene     

Zhang Qian  Zhang Zhi-yi  Lin Shan-zhi  Lin Yuan-Zhen  Yang Le 《中国林学(英文版)》2005,7(3):28-34

To have a preliminary insight into biosafety of genetically transformed hybrid triploid poplars (Populus tomentosa × P. bolleana) × P. tomentosa with the cowpea trypsin inhibitor (CpTI) gene, two layers of rhizospheric soil (from 0 to 20 cm deep and from 20 to 40 cm deep, respectively) were collected for microorganism culture, counting assay and PCR analysis to assess the poten-tial impact of transgenic poplars on non-target microorganism population and transgene dispersal. When the same soil layer of suspension stock solution was diluted at both 1:1 000 and 1:10 000 rates, there were no significant differences in bacterium colony numbers between the inoculation plates of both transgenic and non-transgenic poplars. The uniform results were revealed for both soil layer suspension solutions of identical poplars at both dilution rates except for non-transgenic poplars at 1:10 000 dilution rates from the same type of soil. No significant variation in morphology of both Gram-positive and Gram-negative bacteria was observed under the microscope. The potential transgene dispersal from root exudates or fallen leaves to non-target microbes was repudiated by PCR analysis, in which no CpTI gene specific DNA band was amplified for 15 sites of transgenic rhizospheric soil samples. It can be concluded that transgenic poplar with the CpTI gene has no severe impact on rhizospheric microorganisms and is tentatively safe to surrounding soil micro-ecosystem.  相似文献   

肚倍蚜,美灰藓最佳生态条件与肚倍基地建设   总被引：2，自引：0，他引：2  

郑德国  王贤斌 《湖北林业科技》1997,(3):8-12

肚倍蚜，美灰藓最佳生态条件研究表明，由光照强度、湿度以及风速等因素决定的环境是制约肚倍丰产、稳产的关键；据此对肚倍基地建设提出若干建议。  相似文献   

Micropropagation and tissue culture of Eucalyptus-a review     

Le Roux JJ  Staden JV 《Tree physiology》1991,9(4):435-477

Micropropagation has the potential to provide very high multiplication rates of selected tree genotypes, with resulting short-term silvicultural gains. Aseptic cultures have been established from seeds, seedlings, shoots, flowers and lignotubers. Callus cultures have been established from a wide range of tissue sources for at least 30 species of Eucalyptus. Plant regeneration from callus was successful for 12 of these species. Micropropagation through axillary proliferation, or adventitious shoot proliferation on nodal explants, or both, has been successful. An agar-based medium of Murashige and Skoog with a low auxin/cytokinin ratio is most commonly used for shoot multiplication. Vitrification and shoot senescence remain problems. Gibberellic acid was added in some media to stimulate shoot elongation. Various media are used for in vitro root initiation. Suspension and protoplast cultures have been achieved and plants have been regenerated from protoplasts. In vitro techniques are presently being applied to Eucalyptus to achieve genetic transformations.  相似文献   

Parental participation in progeny and effective population sizes in experimental seed orchards of wild cherry Prunus avium L. (Batsch)     

Stéphanie Mariette  Emilie Balsemin  Solenn Stoeckel  Muriel Tavaud  Hervé Le Bouler  Frédérique Santi  Michel Verger 《Annals of Forest Science》2007,64(5):533-539

Parents and progenies genetic diversity, and male and female contributions to the seed crop were assessed in three experimental Prunus avium seed orchards. Collected data were used to compare different effective population sizes, based on phenological, seed crop and paternity analysis. Our results did not show any difference of genetic diversity between parents and progenies. A limited pollen pollution was detected. We showed that distance and coflowering among clones had a significant effect on effective pollination, and a significant effect of the production of flowers was revealed in one of the seed orchards. Our study also revealed a quite low number of effective size of fathers per mother, but high effective sizes of mothers, fathers and parents at the level of the seed orchard. Finally, the calculation of effective size of mothers, fathers and parents was not highly modified when having the complete information based on the paternity analysis.  相似文献   

Identification and characterization of water-stress-responsive genes in hydroponically grown maritime pine (Pinus pinaster) seedlings     

Dubos C  Le Provost G  Pot D  Salin F  Lalane C  Madur D  Frigerio JM  Plomion C 《Tree physiology》2003,23(3):169-179

  相似文献   

Spatial pattern of the density of Armillaria epiphytic rhizomorphs on tree collar in an oak stand     

B. Marçais  O. Caël 《Forest Pathology》2006,36(1):32-40

The density of Armillaria gallica epiphytic rhizomorphs on tree collar was mapped in a young stand of pedunculate oaks (Quercus robur). A quick method to estimate the rhizomorph density was developed, investigating 19 trees, and was used in the subsequent study. The method consists of measuring the frequency of rhizomorphs present on a grid applied to an exposed small area of the tree collar. The pattern in tree collar rhizomorph density was closely related to the pattern of stump colonization by Armillaria and stumps were therefore important as inoculum sources. Rhizomorph density on tree collar showed a strong aggregated spatial pattern which could not be explained by variability in the soil characteristics, in particular waterlogging, or by a spatial pattern in tree vigour. Moreover, rhizomorph density on tree collar did not depend on their dominance status.  相似文献   

Localized graft incompatibility in pear/quince (Pyrus communis/Cydonia oblonga) combinations: multivariate analysis of histological data from 5-month-old grafts     

Ermel FF  Kervella J  Catesson AM  Poëssel JL 《Tree physiology》1999,19(10):645-654

To characterize the structural events associated with incompatibility of graft development, we conducted a histological study of compatible and incompatible pear/pear and pear/quince grafts that had been grown for five months in a greenhouse. Multivariate analysis of histological data describing the structure of the graft union allowed us to discriminate between compatible and incompatible combinations before either macroscopic examination or qualitative microscopic examination differences between graft combinations became evident. The histological variables responsible for the discrimination between incompatible and compatible unions were related to three typical symptoms of graft incompatibility: bark discontinuity, which was the main feature; cambial dysfunction; and accumulation of starch in the scion. Little cell necrosis was observed at the interface of incompatible grafts at the 5-month stage of graft development. Multivariate analysis of histological data provides a new tool for studying early structural events resulting from the graft incompatibility response and for diagnosing early graft incompatibility.  相似文献   

马鞍山林场松墨天牛病原微生物种类调查鉴定及毒力测定研究          下载免费PDF全文

韩兵  朴春根  汪来发  李永  申相澈  郑荣镇 《林业科学研究》2007,20(2):204-208

在马鞍山市马鞍山林场,对松材线虫病(Bursaphelenchus xylophilus)的传媒昆虫松墨天牛(Monochamus alternatus)的病原微生物进行调查,结果鉴定了8种真菌和1种细菌.对松墨天牛幼虫的致病率测定显示不同的微生物种类和同一种白僵菌(Beauveria bassiana)的不同菌株均有显著差异.白僵菌的高毒力菌株营养生长无明显差异,而产孢量有明显差异.通过测定,白僵菌菌株226可能是优良菌株,对生物防治松黑天牛方面有潜在的实用价值.  相似文献   

Shoot water status and ABA responses of transgenic hybrid larch Larix kaempferi x L. decidua to ectomycorrhizal fungi and osmotic stress     

Rincón A  Priha O  Lelu-Walter MA  Bonnet M  Sotta B  Le Tacon F 《Tree physiology》2005,25(9):1101-1108

It has been postulated that osmotic effects on plant tissue are mediated by abscisic acid (ABA). Hybrid larch (Larix kaempferi (Lambert) Carr. x L. decidua Mill.) plantlets, transformed with the ABA-inducible wheat Em promoter associated with the Gus reporter gene, were axenically inoculated with two ectomycorrhizal fungi: Cenococcum geophilum Fr., considered tolerant to water stress, and Laccaria bicolor (Marie) Orton, considered less tolerant to drought. The mycorrhizal and non-mycorrhizal transgenic plantlets were subjected to osmotic stress by adding polyethylene glycol (PEG) to the culture medium. In the presence of PEG, L. bicolor and C. geophilum reduced shoot water potential and turgor potential, but increased host osmotic potential. Treatment of plantlets with PEG induced a significant increase in endogenous ABA concentrations. Laccaria bicolor and C. geophilum behaved similarly and significantly decreased the ABA response of plantlets to PEG treatment. Moreover, inoculation with either fungus regulated the ABA response of the plantlets even when the fungus was separated from the host by a cellophane sheet that prevented mycorrhiza formation. Although the wheat Em promoter was inducible in larch plantlets, it was not regulated by endogenous ABA. Induction of the wheat Em promoter in larch plantlets depended on organ type, with maximum induction in the root apex. Induction of the Em promoter was significantly decreased by mycorrhizal inoculation.  相似文献   

Effects of heat treatment on brittleness of <Emphasis Type="Italic">Styrax tonkinensis</Emphasis> wood     

Le Xuan Phuong  Satoshi Shida  Yukie Saito 《Journal of Wood Science》2007,53(3):181-186

A new approach is proposed for the evaluation of the brittleness of heat-treated Styrax tonkinensis wood. Heat treatment made wood more brittle when wood was heated at a higher temperature or for a longer time. The brittleness increased to four times that of the control when wood was heated at 200°C for 12 h. For treatment at 160°C, the increase in brittleness without any change in weight is thought to be possibly caused by the relocation of lignin molecules. At higher temperatures, loss of amorphous polysaccharides due to degradation is thought to become the main factor affecting brittleness. The crystallites that were newly formed after 2 h of treatment showed brittleness that was different from that of the inherent crystallites remaining after 12 h of heat treatment. This inherent crystalline cellulose possibly plays a role in brittleness. There is also the possibility of using color to predict the brittleness of heat-treated wood.  相似文献