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1.
INTRODUCTION Plants have defense mechanisms against patho-gen infection by inducing systemic resistance in re-sponse to localized pretreatment with biological cotrol agents, thus making them resistant to subsequpathogen infection (Caruso et al., 1999; Hammschmidt, 1999; Mohammadi and Kazemi, 2002; yada et al., 1995; Pozo et al., 2002; Ray et al., 199Biological control of plant pathogens has receivmuch more attention. It is well known that plants amicroorganisms symbiosis is a defense m… 相似文献
2.
Aquilaria agallocha can produce fragrant agarwood used for incense, traditional medicine and other products. An efficient plant regeneration
system was established via organogenesis from shoots developed from seedlings ofAquilaria agallocha. Shoots generated many buds on MS medium supplemented with 1.3 μmol/L BA (6-benzylaminopurine) in the first 7 weeks, and
the buds elongated on MS medium with 1.3 μmol/L BA+0.5 μmol/L NAA (naphthaleneacetic acid) in another 7 weeks, 2.3 shoots
2 cm in length per explant were obtained within 14 weeks. Plantlets were rooted on 1/2 MS medium after being immersed in 5
μmol/L NAA for 48 h, 96.7% of the roots grew up two weeks later. All plantlets that survived acclimatization grew well in
the pots.
Project supported by the National Natural Science Foundation of China (No. 30070066) and the Science and Technology Project
of Guangzhou City (No. 2003J1-C0241), China 相似文献
3.
Insertion mutagenesis has become one of the most popular methods for gene functions analysis. Here we report a two-elementAc/Ds transposon system containing enhancer trap and gene trap for gene tagging in rice. The excision ofDs element was examined by PCR amplification. The excision frequency ofDs element varied from 0% to 40% among 20 F2 populations derived from 11 differentDs parents. Southern blot analysis revealed that more than 70% of excisedDs elements reinserted into rice genome and above 70% of the reinsertedDs elements were located at different positions of the chromosome in rice. The result of histochemical GUS analysis indicated
that 28% of enhancer trap and 22% of gene trap tagging plants displayed GUS activity in leaves, roots, flowers or seeds. The
GUS positive lines will be useful for identifying gene function in rice.
Project supported by the Hi-Tech Research and Development Program (863) of China (No. 2002AA2Z1003) 相似文献
4.
转基因烟草感染马铃薯Y病毒脉坏死株系后某些酶活性变化的比较研究 总被引：1，自引：0，他引：1
烟草感染马铃薯Y病毒脉坏死株系后,过氧化物酶活性升高,但非转基因敏感烟草升高的幅度大于转基因抗病烟草;同时,非转基固敏感烟草的苯丙氨酸解氨酶和多酚氧化酶活性均增高,并且都出现两个活性高峰,但转基因抗病烟草的苯丙氨酸解氨酶活性仅出现第一个活性高峰,随后其活性值降低并逐渐恢复至未接种时的水平,而多酚氧化酶活性则降低;在未感染PVYN的情况下,转基因抗病烟草的过氧化物酶、苯丙氨酸解氨酶和多酚氧化酶活性均比非转基因敏感烟草高． 相似文献
5.
Embryogenic calli were induced from the seeds of creeping bentgrass (Agrostis palustris Huds.) cv. Regent and colonial bentgrass (Agrostis Tenuis Sibth. Fl. Oxen.) cv. Tiger. The embryogenic calli were precultured on fresh medium for 4–7 days and then co-cultivated withAgrobacterium tumefaciens, LBA4404. which contains plasmid vector-pSBGM harboring bar coding region, synthetic green fluorescent protein (sGFP) coding
region and matrix attachment region (MAR). After 3 days of co-cultivation, the calli were washed thoroughly and transferred
to MS medium containing 2 mg/L of 2, 4-D, 12–15 mg/L phosphinothricin (PPT) and 250 mg/L of cefotaxime. After 2–3 months of
selection, the actively growing calli of ‘Regent’ and ‘Tiger’ were transferred to MS medium with 12–15 mg/L PPT and 250 mg/L
cefotazime for regeneration. The putative transformants were maintained on MS medium with 3 mg/L PPT for long period but control
died within 1 month. After establishing in greenhouse, the transformants also showed strong resistance to 0.4% of herbicide
Basta but control plants died within 2 weeks. Under confocal microscope, both young leaves and roots showed significant GFP
expression. PCR analysis revealed the presence of a DNA fragment of GFP gene at the expected size (380 bp) in the transformants
and its absence in a randomly selected control plant. 相似文献
6.
Haseeb Akhtar Sharma Anita Shukla Prabhat Kumar 《Journal of Zhejiang University. Science. B》2005,6(8):736-742
Studies were conducted under pot conditions to determine the comparative efficacy of carbofuran at 1 mg a.i./kg soil, bavistin
at 1 mg a.i./kg soil, neem (Azadirachta indica) seed powder at 50 mg/kg soil, green mould (Trichoderma harzianum) at 50.0 ml/kg soil, rhizobacteria (Pseudomonas fluorescens) at 50.0 ml/kg soil against root-knot nematode,Meloidogyne incognita-wilt fungus,Fusarium oxysporum disease complex on green gram,Vigna radiata cv ML-1108. All the treatments significantly improved the growth of the plants as compared to untreated inoculated plants.
Analysis of data showed that carbofuran andA. indica seed powder increased plant growth and yield significantly more in comparison to bavistin andP. fluorescens. Carbofuran was highly effective against nematode, bavistin against fungus,A. indica seed powder against both the pathogens and both the bioagents were moderately effective against both the pathogens. 相似文献
7.
Objective: To evaluate the interaction between serum levels of soluble intercellular adhesion molecule-1 (sICAM-1) andHelicobacter pylori (H. pylori) infection in patients with chronic gastritis and peptic ulcer. Methods: The serum levels of sICAM-1 in 205 patients with
chronic gastric diseases were detected by ELISA method and the status ofH. pylori was determined by histologic examination, RUT,14C-UBT, and serology. The sera obtained from 18 healthy volunteers served as controls. Results: The serum levels of sICAM-1
were significantly higher in patients withH. pylori positive than those of H. pylori negative (889.43±32.52 ng/ml vs. 747.07±30.45 ng/ml,P<0.05). The serum levels of sICAM-1 in patients with mild, moderate and severe infection ofH. pylori were 841.68±72.36 ng/ml, 905.43±37.59 ng/ml and 1012.54±49.34 ng/ml, respectively (P<0.05). The serum levels of sICAM-1, proved to be significantly correlated with the density ofH. pylori colonization in gastric mucosa (r
s=0.316,P<0.001). The serum levels of sICAM-1 in patients with chronic gastritis and peptic ulcer were significantly higher than those
in healthy controls (P<0.05). Conclusions: These results indicated thatH. pylori infection up-regulates the expression of sICAM-1. 相似文献
8.
Insecticidal effects of different doses of the dust and methanol extracts of Garcinia kolae on Collosobruchus maculatus and Sitophilus zeamais were tested. The dust had no significant effect on the two insects; none of them died even at 3 d after treatment. The methanol
extracts, however, had rapid lethal effects on both C. maculatus and S. zeamais. The mortality of C. maculatus by the lowest concentration of methanol extracts ranged from 95%∼100% whereas in S. zeamais, the mortality ranged from 87.5%∼100% and 70%∼100% in concentrations of 1 g extract+3 ml methanol and 1 g extract+5 ml methanol,
respectively, from 24 to 48 h. The least concentration of 1 g extract+15 ml methanol had no significant lethal effect on Sitophilus zeamais.
相似文献
9.
Zhang Xin Zhang Bing-xin Zhang Zhen Shen Wei-feng Yang Ching-hong Yu Jing-quan Zhao Yu-hua 《Journal of Zhejiang University. Science. B》2005,6(8):770-777
Fusarium head blight (FHB) caused byFusarium graminearum is a devastating disease that results in extensive yield losses to wheat and barley. A green fluorescent protein (GFP) expressing
plasmid pRP22-GFP was constructed for monitoring the colonization of two biocontrol agents,Brevibacillus brevis ZJY-116, on the spikes of barley and their effect on suppression of FHB. Survival and colonization of theBrevibacillus brevis ZJY-1 andBacillus subtilis ZJY-116 strains on spikes of barley were observed by tracking the bacterial transformants with GFP expression. Our field
study revealed that plasmid pRP22-GFP was stably maintained in the bacterial strains without selective pressure. The retrieved
GFP-tagged strains showed that the bacterial population fluctuation accorded with that of the rain events. Furthermore, both
biocontrol strains gave significant protection against FHB on spikes of barley in fields. The greater suppression of barley
FHB disease was resulted from the treatment of barley spikes with biocontrol agents before inoculation withF. graminearum.
Project supported by the National Natural Science Foundation of China (No. 30230250) and Science and Technology Committee
of Zhejiang Province (No. 2003C22029), China 相似文献
10.
选取《说文解字·羊部》中的羊、羍、羭、、羯、、群、等词,通过据音系联的音系法,即在不明语根的情况下,不分源流,只将部分同族词系联起来,说明这些词的命名依据。 相似文献
11.
In this paper, the Tφ-convex functions were introduced as a generalizations of convex functions. Then the characteristics of the Tφ-convex functions were discussed. Furthermore, some new inequalities for the Tφ-convex functions were derived. 相似文献
12.
《宝剑记》主要取材于我国古典小说《水浒传》中"林冲落草"这段故事。相较来看,《宝剑记》继承了《水浒传》的很多方面,包括主要人物设置,故事情节内容,"忠奸"主题思想。除此,《宝剑记》在人物形象、情节脉络、中心矛盾、起因结局等方面又有所创新。《宝剑记》对《水浒传》的改编凸显出明中叶反封建专制统治的社会思潮和人的自我意识的觉醒,也是作者李开先个人心灵世界的直接映现,具有明显的进步性与现实意义。 相似文献
13.
14.
Strain improvement and medium optimization to increase the productivity of spiramycin were carried out. Of oil tolerant mutant
strains screened, one mutant,Streptomyces ambofaciens XC 2–37, produced 9% more spiramycin than the parent strainS. ambofaciens XC 1–29. The effects of soybean oil and propyl alcohol on spiramycin production withS. ambofaciens XC 2–37 were studied. The potency ofS. ambofaciens XC 2–37 was improved by 61.8% with addition of 2% soybean oil in the fermentation medium and 0.4% propyl alcohol at 24 hours
after incubation. The suitable time for feeding propyl alcohol is at 24 hours after incubation in flask fermentation and at
20 hours after incubation in fermentor fermentation. The new process withS. ambofaciens XC 2–37 was scaled up for industrial scale production of spiramycin in a 60 m3 fermentor in Xinchang Pharmaceutical Factory, Zhejiang Medicine Company, Ltd., China, and the potency and productivity of
fermentation were improved by 42.9%. 相似文献
15.
面对"道"难以言明的困境,《老子》采用了"以象言道"的方式。"象喻"是《老子》特殊的言道方式,具体表现为:取譬引喻,以水、谷等自然之"象"形容"道";执象悟道,由草木、婴儿等"象"体悟"道";以物观物,通过对"象"的整体直观抵达"道"之本质。这种言道方式是诗性的,对后世文学创作与文学批评产生了极其重要的影响,催生了意象论及"以象喻文"话语方式,开启了对澄明本真之境的审美追求。 相似文献
16.
在李大钊一生中,曾与研究系发生密切关系,他留学日本有赖于研究系的资助,但思想迅速发展中的李大钊已与研究系的政治理念产生根本分歧。《别泪》一文既是他对研究系的诚恳忠告,也是其坚定政治理念的宣言。 相似文献
17.
Plastids of nongreen tissues import carbon as a source of biosynthetic pathways and energy, and glucose 6-phosphate is the
preferred hexose phosphate taken up by nongreen plastids. A cDNA clone encoding glucose 6-phosphate/phosphate translocator
(GPT) was isolated from a cDNA library of immature seeds of rice and named asOsGPT. The cDNA has one uninterrupted open reading frame encoding a 42 kDa polypeptide possessing transit peptide consisting of
70 amino acid residues. TheOsGPT gene maps on chromosome 8 of rice and is linked to the quantitative trait locus for 1000-grain weight. The expression ofOsGPT is mainly restricted to heterotrophic tissues. These results suggest that glucose 6-phosphate imported viaGPT can be used for starch biosynthesis in rice nongreen plastids.
Project supported by National Natural Scienc Foundation of China (No.39830250) and Natural Science Foundation of Zhejiang
Province (No.2A0106), China. The nucleotide sequence data will appear in the GenBank under accession number AF375053. 相似文献
18.
Wu Tian-xing Song Zeng-fu Cai Li-sheng Ding Xue-yan Yu Qing-sen 《Journal of Zhejiang University. Science. B》2005,6(8):798-802
Effects of dietary supplementation with fructooligosaccharides on the excretion of nitrogen and phosphorus inMiichthys miiuy fries were investigated. Nine hundredMiichthys miiuy fries were divided into 3 groups, each with triplicates. The basal diet and the basal diet supplemented with carnitine groups
were considered as the negative and positive controls respectively. Results showed that the nitrogen concentration in excreted
feces decreased significantly in fries fed the diet supplementation with 1000×10−6 fructooligosaccharides and 200×10−6 carnitine (P<0.05). The ammonic-nitrogen concentration decreased significantly in the carnitine group only (P<0.05), indicating the decreasing tendency caused by the supplementation with fructooligosaccharides. Supplementation with
both did not have significant effects on the concentration of phosphorus in feces ofMiichthys miiuy fries.
Project supported by Public Bidding Item in Key Research of Zhejiang Province (No. 02110281-2) and Ningbo Tackle Key Problem
for Agricultural Development (No. 2004C-100030), China 相似文献
19.
Objective: To determine the existence of genus-specific antigens in outer membrane proteins (OMPs) ofleptospira with different virulence. Methods: Microscope agglutination test (MAT) was applied to detect the agglutination between commercial
rabbit antiserum against leptospiral genus-specific TR/Patoc I antigen and 17 strains ofLeptospira interrongans belonging to 15 serogroups and 2 strains ofLeptospira biflexa belonging to 2 serogroups. The outer envelopes (OEs) ofLinterrogans serogroupIcterohaemorrhagiae serovarlai strainlai (56601) with strong virulence and serogroupPomona serovarpomona strainLuo (56608) with low virulence, andL. biflexa serogroupSemaranga serovarpatoc strainPatoc I without virulence were prepared by using the method reported in Auranet al. (1972). OMPs in the OEs were obtained by treatment with sodium deoxycholate. SDS-PAGE and western blot were used for analyzing
the features of the OMPs on electrophoretic pattern and the immunoreactivity to the antiserum against TR/Patoc I antigen,
respectively. Results: All the tested strains belonging to different leptospiral serogroups agglutinated to the antiserum
against leptospiral genus-specific TR/Patoc I antigen with agglutination titers ranging from 1:256–1:512. A similar SDS-PAGE
pattern of the OMPs from the three strains ofleptospira with different virulence was shown and the molecular weight of a major protein fragment in the OMPs was found to be approximately
60 Kda. A positive protein fragment with approximately 32 KDa confirmed by Western blot, was able to react with the antiserum
against leptospiral genus-specific TR/Patoc I antigen, and was found in each the OMPs of the three stains ofleptospira. Conclusion: There are genus-specific antigens on the surface ofL.interrogans andL.biflexa. The OMP with molecular weight of 32 KDa may be one of the genus-specific protein antigens ofleptospira.
Project (No. 39970678) supported by the National Natural Science Foundation of China 相似文献
20.
Objective: To investigate the distribution ofH. pylori antigens in the gastric mucosa in patients withH. pylori infection, and the relationship between the distribution and gastric cancer. Methods: Of 112 patients confirmed by pathological
study to have chronic superficial gastritis, precancerous changes (chronic atrophic gastritis, intestinal metaplasia or atypical
hyperplasia) and gastric cancer, 28 wereH. pylori negative and 84 wereH. pylori positive.H. pylori antigens in the gastric mucosa were detected by immunohistochemistry. Results: TheH. pylori positive group, comprised 12 of 22 (50.0%) in the chronic superficial gastritis group, 22 of 25 (88.0%) in the precancerous
changes group and 13 of 35 (37.1%) in the gastric cancer group. The positive rates ofH. pylori antigens in the cytoplasm progressively increased, respectively at 0.0% (0/12), 63.6% (14/22) and 84.6% (11/13) for the same
groups (χ
2=19.76,P=0.000);H. pylori antigens were located in the mucus layer and above the neck of the mucosal gland in 9 of 12 (75.0%) cases with chronic superficial
gastritis, at the neck of the mucosal gland and the isthmus in 12 of 22 (54.5%) cases with precancerous changes, below the
isthmus in 9 of 13 (69.2%) cases with gastric cancer (χ
2=25.30,P=0.000). In theH. pylori negative group, noH. pylori antigen was observed. Conclusion: With the progression of chronic superficial gastritis→precancerous changes→gastric cancer,H. pylori antigens progressively migrated from the outer part to the inner part of the cell, and from the superficial to the deep gastric
mucosa. 相似文献