拟南芥HyPRP蛋白AZI1在转基因烟草中的亚细胞定位及其对灰葡萄孢的抗性

通过农杆菌转化法得到了整合有拟南芥AZII基因的烟草植株,进一步利用转基因烟草分析了AZI1蛋白的亚细胞定位及其对真菌病原体的抗性特征。在上下游引物5’端分别引入NcoI和SpeI酶切位点,采用高保真耐热DNA聚合酶彤Pfu从拟南芥Co1-0生态型基因组DNA扩增AZII基因的编码序列,用NcoI和Spel对扩增片段和pCAMBIA1302质粒载体进行双酶切,通过T4DNA连接酶构建产生AZII-GFP融合表达载体。用包含融合表达载体的农杆菌细胞转化烟草叶片,经潮霉素选择获得了完整的再生植株,并收取了T。代种子。激光共聚焦显微观察发现,AZI1蛋白主要定位于细胞表面。病原体侵染结果显示,AZI1基因能够明显提高烟草对灰葡萄孢的抗性。说明AZI1蛋白通过分泌途径被定位到细胞表面后,能够抑制真菌病原体对植物组织的侵染过程。     

Resistance of Botrytis cinerea to dicarboximide fungicides in protected crops

Dicarboximide fungicides have been used for the control of grey mould in protected crops in Crete since 1977. During the 1980 growing season a decline of their efficacy was observed. In successive surveys carried out in May 1980, February 1981 and May 1981 in 28, 10 and 13 plastic houses repectively, a considerable proportion of resistant strains was found. From each of the plastic houses sampled mostly either only resistant or only sensitive strains were isolated. In three of the plastic houses with resistant strains there was an acute disease control problem. The ED₅₀ of 15 resistant strains studied was in the area of 3·5 μg/ml vinclozolin as compared with 0·2 μg/ml for the wild type strains. The vinclozolin-resistant strains were also resistant to procymidone, iprodione, and dicloran. In most of the cases strains resistant to vinclozolin were also resistant to benomyl and strains sensitive to vinclozolin were also sensitive to benomyl. In the absence of fungicide, resistant strains grew more slowly on PDA than sensitive ones, but spores germinated equally well. Vinclozolin (0·75 mg a.i./ml) did not protect eggplant seedlings against resistant strains but gave satisfactory control of sensitive ones.     

Enhanced Botrytis cinerea Resistance of Arabidopsis Plants Grown in Compost May Be Explained by Increased Expression of Defense-Related Genes,as Revealed by Microarray Analysis

Composts are the products obtained after the aerobic degradation of different types of organic matter waste and can be used as substrates or substrate/soil amendments for plant cultivation. There is a small but increasing number of reports that suggest that foliar diseases may be reduced when using compost, rather than standard substrates, as growing medium. The purpose of this study was to examine the gene expression alteration produced by the compost to gain knowledge of the mechanisms involved in compost-induced systemic resistance. A compost from olive marc and olive tree leaves was able to induce resistance against Botrytis cinerea in Arabidopsis, unlike the standard substrate, perlite. Microarray analyses revealed that 178 genes were differently expressed, with a fold change cut-off of 1, of which 155 were up-regulated and 23 were down-regulated in compost-grown, as against perlite-grown plants. A functional enrichment study of up-regulated genes revealed that 38 Gene Ontology terms were significantly enriched. Response to stress, biotic stimulus, other organism, bacterium, fungus, chemical and abiotic stimulus, SA and ABA stimulus, oxidative stress, water, temperature and cold were significantly enriched, as were immune and defense responses, systemic acquired resistance, secondary metabolic process and oxireductase activity. Interestingly, PR1 expression, which was equally enhanced by growing the plants in compost and by B. cinerea inoculation, was further boosted in compost-grown pathogen-inoculated plants. Compost triggered a plant response that shares similarities with both systemic acquired resistance and ABA-dependent/independent abiotic stress responses.     

Co-expression of a Modified Maize Ribosome-inactivating Protein and a Rice Basic Chitinase Gene in Transgenic Rice Plants Confers Enhanced Resistance to Sheath Blight

Chitinases, -1,3-glucanases, and ribosome-inactivating proteins are reported to have antifungal activity in plants. With the aim of producing fungus-resistant transgenic plants, we co-expressed a modified maize ribosome-inactivating protein gene, MOD1, and a rice basic chitinase gene, RCH10, in transgenic rice plants. A construct containing MOD1 and RCH10 under the control of the rice rbcS and Act1 promoters, respectively, was co-transformed with a plasmid containing the herbicide-resistance gene bar as a selection marker into rice by particle bombardment. Several transformants analyzed by genomic Southern-blot hybridization demonstrated integration of multiple copies of the foreign gene into rice chromosomes. Immunoblot experiments showed that MOD1 formed approximately 0.5% of the total soluble protein in transgenic leaves. RCH10 expression was examined using the native polyacrylamide-overlay gel method, and high RCH10 activity was observed in leaf tissues where endogenous RCH10 is not expressed. R₁ plants were analyzed in a similar way, and the Southern-blot patterns and levels of transgene expression remained the same as in the parental line. Analysis of the response of R₂ plants to three fungal pathogens of rice, Rhizoctonia solani, Bipolaris oryzae, and Magnaporthe grisea, indicated statistically significant symptom reduction only in the case of R. solani (sheath blight). The increased resistance co-segregated with herbicide tolerance, reflecting a correlation between the resistance phenotype and transgene expression.     

转拟南芥P5CS1基因增强羽衣甘蓝的耐旱性

为提高羽衣甘蓝的耐旱性,本文将拟南芥Δ1-吡咯啉-5-羧酸合成酶（P5CS1）基因经农杆菌介导转入羽衣甘蓝植株中,检测转基因株系与野生型植株在干旱胁迫下P5CS1 mRNA表达量、幼苗脯氨酸含量、株系根系性状、整株干重、鲜重和整株存活率。结果表明,在15%PEG6000渗透胁迫下,转基因植株的P5CS1基因mRNA表达量明显增加,转基因植株脯氨酸含量是野生型的2.4倍;主根长、最长侧根长、侧根数目、整株干重和鲜重均高于野生型,干重/鲜重则低于野生型,转基因植株的平均存活率为78%,极显著高于野生型。数据显示,AtP5CS1基因在羽衣甘蓝中的表达明显改善了转基因植株的耐旱性。     

Expression of the Bar Gene Confers Herbicide Resistance in Transgenic Lettuce

Resistance to bialaphos, a broad-spectrum herbicide, was introduced into Lactuca sativa cv. Evola by Agrobacterium tumefaciens-mediated transformation. A. tumefaciens strains 0310 and 1310, both carrying the bialaphos resistance (bar) and neomycin phosphotransferase (nptII) genes, were used for transformation. Primary transformants were selected on kanamycin sulphate-supplemented shoot regeneration medium. Integration of both transgenes was confirmed by non-radioactive Southern hybridisation. The hypervirulent plasmid ToK47 in A. tumefaciens strain 1310 generated multiple insertions of T-DNA in some transgenic plants; the absence of pToK47 (strain 0310) resulted in single gene inserts in all plants tested. Resistance to glufosinate ammonium was observed in axenic seedlings grown on medium supplemented with the herbicide at 5 mg l–1 and in glasshouse-grown plants sprayed with the compound at 300 mg l–1. Stable expression of the bar gene was observed in R2 generation plants. The kanamycin resistance of R1 seedlings was observed by germinating seeds on medium supplemented with 200 mg l–1 kanamycin sulphate. The presence of NPTII protein and PAT enzyme activity were demonstrated by ELISA and PAT enzyme assay respectively. Transgenes segregated in a Mendelian fashion in some plant lines in the R1 generation; herbicide resistance also segregated in the expected ratio in the R2 generation in most transgenic lines. This study confirmed that an agronomically important transgene can be integrated and stably expressed over several generations in lettuce.     

Resistance to Botrytis cinerea in canes of Rubus idaeus and some related species

Mycelial inoculation of canes with Botrytis cinerea proved a useful method for assessing Rubus material for resistance. When canes were inoculated in summer resistant genotypes developed relatively small lesions which produced few small sclerotia in the following spring. The size of lesions in autumn generally provided the best discrimination between genotypes. Very strong resistance was found in several species, of which Rubus pileatus and R. occidentalis are the most useful for breeding; hybrids of raspberry with these species or with R. crataegifolius also had strong resistance. The resistance shown by a derivative of red raspberry cv. Chief was less strong, as was the resistance conferred by gene H, which determines cane pubescence.     

Chitinase family genes in grape differentially expressed in a manner specific to fruit species in response to Botrytis cinerea

Molecular Biology Reports - Chitinases (Chi), an important resistance-related protein, act against fungal pathogens by catalyzing the fungal cell wall, whereas are involved in different biological...     

Effect of UV-C on Phytoalexin Accumulation and Resistance to Botrytis cinerea in Stored Carrots

The effect of UV-C (220–280 nm) on the accumulation of phytoalexin and resistance to Botrytis cinerea was studied in cold-stored carrots. Carrots were surface-wounded, treated with a range of UV doses and stored at 1 °C for 25 days in lots of 22 roots. The level of the phytoalexin, 6-methoxymellein, in each lot was then assayed in the peel of eight roots. Twelve of the remaining roots were subsequently inoculated with mycelial plugs to evaluate their level of disease resistance. The elicitation of 6-methoxymellcin by UV increased significantly the resistance of the roots to B. cinerea. The effect of UV in freshly harvested carrots was curvilinear, showing an optimum between 0.44 and 0.88 Merg/cm². However, only a linear relationship was observed with aged (stored for 4 months at 1 °C) carrots for the same doses, suggesting a modification in the response to UV with age. Wounding was necessary for carrots kept at 1 °C to respond to UV treatment. Neither UV nor wounding alone caused any elicitation at this temperature. Since unwounded roots could respond to UV at 20 °C, it is hypothesized that the level of physiological activity of the roots determines their response to UV. An increase in the physiological activity by higher temperatures or wounding would allow the elicitation process to take place. Since UV irradiation can increase the level of disease resistance in treated tissues, this treatment has potential as an alternative method for the control of post-harvest diseases m carrots.     

病毒编码基因介导的植物病毒抗性机理研究进展

根据植物自身病毒编码基因的不同,重点介绍了其病毒抗性机理的研究进展。     

Biological Control of Botrytis cinerea Pers. ex Fr. in Strawberry by Paenibacillus polymyxa (Isolate 18191)

Isolate 18191, obtained from mature strawberry fruit and determined as Paenibacillus polymyxa has shown an antagonistic potential against Botrytis cinerea , the causal agent of grey mould in strawberries. Germ tube growth of conidia of B. cinerea was strongly inhibited by the culture suspension of the antagonist in aqueous strawberry fruit pulp suspension (1%) but germination rate of conidia was not affected. The application of the culture suspension and the washed cells on detached strawberry leaf discs reduced conidiophore density of B. cinerea by 67 and 84%, respectively. The treatment of detached leaf discs with culture suspensions of different cell densities (1 × 10⁶, 1 × 10⁷, 1 × 10⁸) showed that the lowest density already reduced incidence of B. cinerea by 68% after 8 days incubation period. Investigating the influence of the temperature on the effectiveness of P. polymyxa it was observed that the antagonist was highly effective already at 10°C and reduced incidence and conidiophore density of B. cinerea by 53 and 58%, respectively. In 3-year field trials the effectiveness of P. polymyxa was in a range of 24–36% as compared to the water control.     

苜蓿高含硫氨基酸蛋白转基因植株再生

通过农杆菌介导法将高含硫氨基酸蛋白基因转入苜蓿,成功地诱导转基因植株再生,转化植株生长和发育良好,苜蓿子叶外植体是较理想的转化受体。冷凉湿润的环境条件是苜蓿移栽成活率高所必需的。     

Transformation of Terpenoids in Grape Must by Botrytis cinerea

Experiments were done to investigate the volatile components in botrytized grape must and transformation of terpenoids in terpene-supplemented grape must by Botrytis cinerea. Twenty-eight compounds were identified in the volatile concentrate of botrytized must with a combined gas chromatograph-mass spectrometer. No terpenoids were detected in the concentrate. Linalool or terpinen-4-ol decreased a lot when Botrytis cinerea was cultured in the must with these terpenes for 15 days. In linalool-supplemented botrytized must 9 identified and 3 unidentified terpenes were found, while only geranial was detected in terpinen-4-ol-supplemented botrytized must. Botrytis cinerea did not produce terpenoid in grape must without terpenes, but transformed linalool added to grape must into some other monoterpenes.     

转梅PGIP基因增强菊花抗病性研究

通过农杆菌介导法将梅多聚半乳糖醛酸酶抑制蛋白基因(PGIP)转入盆栽小菊品种'05-44-2'中,以提高对真菌病害的抗性.经Hyg抗性筛选,获得232株抗性苗.对其中40株进行PCR检测,有8株扩增出目的条带;对这8株进行RT-PCR检测,发现其中有5个株系有目的条带出现,且发生基因转录.转基因菊花的抗病性检测证实,与对照相比,转基因株系对黑斑病有不同程度的抗性,表现为发病延迟,病情指数降低;株系7抗性最强,其苗期病情指数仅为33.     

Enhanced Resistance to Phytopathogenic Bacteria in Transgenic Tobacco Plants with Synthetic Gene of Antimicrobial Peptide Cecropin P1

Plasmids with a synthetic gene of the mammalian antimicrobial peptide cecropin P1 (cecP1) controlled by the constitutive promoter 35S RNA of cauliflower mosaic virus were constructed. Agrobacterial transformation of tobacco plants was conducted using the obtained recombinant binary vector. The presence of gene cecP1 in the plant genome was confirmed by PCR. The expression of gene cecP1 in transgenic plants was shown by Northern blot analysis. The obtained transgenic plants exhibit enhanced resistance to phytopathogenic bacteria Pseudomonas syringae, P. marginata, and Erwinia carotovora. The ability of transgenic plants to express cecropin P1 was transmitted to the progeny. F₀ and F₁ plants had the normal phenotype (except for a changed coloration of flowers) and retained the ability to produce normal viable seeds upon self-pollination. Lines of F₁ plants with Mendelian segregation of transgenic traits were selected.     

Resistance to Botrytis cinerea in scented geranium transformed with a gene encoding the antimicrobial protein Ace-AMP1

Scented geranium (Pelargonium sp. `Fren-sham') was transformed with a gene encoding an antimicrobial protein (Ace-AMP1) from onion through an Agrobacterium-mediated transformation system. The binary vector pFAJ3033 contained the coding region of the Ace-AMP1 preproprotein-encoding cDNA. Transformants were verified by polymerase chain reaction and Southern blot analysis. Transgenic plants expressing high levels of Ace-AMP1 were identified by immunoblots and those plants were shown to have increased resistance to Botrytis cinerea leaf infection. Received: 23 July 1998 / Revision received: 24 November 1998 / Accepted: 5 December 1998