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1.
纤维亚麻新品种黑亚15号选育报告 总被引:7,自引:1,他引:6
黑亚15号是2004年2月通过黑龙江省农作物品种审定委员会审定通过同意注册的纤维亚麻新品种。原茎、长麻、全麻、种子产量分别为5641.7、897.2、1282.3、619.okg/hm2,分别比对照增产9.3%、20.2%、12.2%、11.9%。长麻率20.O%,比对照高2.8个百分点。纤维强度261.ON。属高纤、优质纤维亚麻新品种。 相似文献
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The pathogenicity and virulence of ten GreekPseudomonas syringae pv.syringae strains from different hosts (citrus, pear, apple, peach and cherry) were evaluated using three different laboratory methods,
which produced results in good agreement. All ten strains were virulent on apple, pear, cherry and peach trees. The extent
of tissue colonized varied considerably among strains and cultivars. On excised shoots and twigs of apple and pear, strains
BPI 176, BPI 203, PI 2 and PI 14 were the most virulent and strains BPI 689, BPI 992, BPI 4, BPI 20, PI 18 and PI 19 were
the least virulent. On excised shoots and twigs of peach and cherry, strains BPI 176, BPI 203, PI 2, PI 14, PI 18 and PI 19
were the most virulent and strains BPI 4 and BPI 20 were the least virulent. Moderate virulence was evinced by strains BPI
689 and BPI 992. These pathogenicity assays are proposed as rapid and reproducible screening systems to evaluate the susceptibility
of apple, pear, cherry and peach cultivars to this bacterial pathogen. 相似文献
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C. Rusterucci Z. Zhao K. Haines D. Mellersh M. Neumann R.K. Cameron 《Physiological and Molecular Plant Pathology》2005,66(6):120
As plants mature it has been observed that some become more resistant to normally virulent pathogens. The ability to manifest the Age-Related Resistance (ARR) response in Arabidopsis to Pseudomonas syringae pathovars tomato (Pst) coincided with the transition to flowering in plants both delayed and accelerated in the transition to flowering. ARR was also associated with a change in PR-1 gene expression, such that young plants expressed PR-1 abundantly at 3 days post inoculation (dpi) while mature plants expressed much less. The Arabidopsis ARR response requires SA accumulation via isochorismate synthase (ICS1) [24]. ICS1 was expressed one dpi with virulent and avirulent Pst in both young and mature plants. The ARR response was also effective versus avirulent Pst providing an additional 4-fold limitation in bacterial growth. Arabidopsis ARR was found to be ineffective against two necrotrophs, Erwinia carotovora subspecies carotovora (bacterium) and Botrytis cinerea (fungus) and one obligate biotroph, Erysiphe cichoracearum (fungus). However, mature wild type, SA-deficient sid2 and NahG plants supported little growth of the obligate biotrophic oomycete, Peronospora parasitica. Therefore ARR to P. parasitica appears to be SA-independent, however the level of ARR resistance was somewhat reduced in these mutants in some experiments. Thus, there may be numerous defence pathways that contribute to adult plant resistance in Arabidopsis. 相似文献
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C. Jacyn Baker Daniel P. Roberts Norton M. Mock Bruce D. Whitaker Kenneth L. Deahl Andrey A. Averyanov 《Physiological and Molecular Plant Pathology》2005,67(6):1322
The plant apoplast is an important mediator of communication between the cell cytoplasm and its surroundings. Plant cell suspensions offer a convenient model system to gain insight into apoplastic physiology. Here, we describe a novel phenomenon that took place when two naturally occurring phenolics were added together to either soybean or tobacco cell suspensions. Acetosyringone (AS) and/or hydroxyacetophenone (HAP), phenolics found in the extracellular/apoplast of tobacco cells, were added to soybean or tobacco cell suspensions undergoing an oxidative burst. Individually, AS appeared to be utilized as a typical peroxidase substrate to scavenge hydrogen peroxide, while HAP was utilized at a much lower rate. However, when added together the rate of utilization of both phenolics increased and surprisingly resulted in the production of hydrogen peroxide. We have further characterized this novel phenomenon in suspension cells. This study demonstrates that certain phenolics in plants can cause co-oxidation which, as in animals, could alter the structure and bioactivity of surrounding phenolics. 相似文献
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AIM and METHODS:To analysis the factor that involved in renal carcinogenesis, we used the bait gene AK001518 to screen GenBank. To understand the relationship between cell cycle related gene(CCRG) and p15, we did RT-PCR and Northern Blot experiments. Then we examined CCRG expression level in renal carcinogenesis. RESULTS:Gained a function unknown gene CCRG that was 67% a mino acid identical with the gene AK001518 that was regulated by p15. It was shown that the CCRG mRNA was dramatically decreased when p15 gene was over-expressed. CCRG expression level was much higher in tumor tissues and cells than normal tissues and cells. CONCLUSION:The novel gene CCRG expressed highly in the renal carcinoma, which might play a significant role in the renal carcinogenesis. 相似文献
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The effect of take-all root lesions on nitrate uptake of wheat was investigated in two experiments under controlled conditions. Plants were supplied with a nutrient solution labelled with 15 N during stem elongation and flowering to assess the distribution of the isotopic tracer in the different plant organs, and particularly in root segments located on both sides of take-all lesions. The 15 N atom percentage excess measured in root segments located below lesions longer than 1 cm was reduced on average by half compared with that in healthy roots and root segments above lesions, reflecting a reduction in nitrogen uptake by these root segments. This reduction probably resulted from the invasion and breakdown of phloem vessels by the fungus hyphae, interrupting energy supply and thus the uptake process. Severely infected plants showed an increase in the uptake rate per unit of efficient root, which appeared to be a compensatory response to reduction of efficient root biomass in order to satisfy shoot nitrogen demand. However, this compensatory response was insufficient to ensure nitrogen accumulation equivalent to that of healthy plants, as reductions in nitrogen accumulated in roots and aerial parts at flowering were up to 56 and 49%, respectively, for plants with more than 50% of the root system below lesions longer than 1 cm. 相似文献