杂草对灭生性除草剂百草枯的抗性问题   总被引：4，自引：0，他引：4  

张宏军  贾富勤  张佳  李晓晶 《农药科学与管理》2003,24(12):26-29

本文综述了百草枯抗性杂草的发生、发展情况以及抗性机理方面的报道，并就抗性杂草的治理提出几点建议。  相似文献   

Tobacco Plants Transformed with an Untranslatable Form of the Coat Protein Gene of the Potato Virus Y are Resistant to Viral Infection     

Khaled Masmoudi  Ines Yacoubi  Afif Hassairi  Lobna Naeit Elarbi  Radhouane Ellouz 《European journal of plant pathology / European Foundation for Plant Pathology》2002,108(4):285-292

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Alternative Route of Infection for Bacterial Seedling Blight of Rice Caused by Burkholderia plantarii     

Hisayoshi MIYAGAWA  Hiroyoshi INOUE 《Journal of General Plant Pathology》2002,68(4):356-362

Burkholderia plantarii , the pathogen of bacterial seedling blight of rice, was detected in paddy water. Its concentration rose in July and August. The bacterial concentration in the paddy water was always higher along levees than at distances more than 5 m from levees. Confirmed to be released into water when graminaceous weeds were immersed, B. plantarii survived for at least 4 days at 30°C. B. plantarii was splashed at least 30 cm upward by rain splash in the field. Harvested seeds, which had been sprayed with B. plantarii released from graminaceous weeds at the flowering stage, retained the bacteria. Bacterial seedling blight occurred when the seeds were then sown in nursery boxes. These results indicated that graminaceous weeds growing on levees of paddy fields are a source of infection of the disease and that rice seeds are infected through the paddy water. Received 23 May 2002/ Accepted in revised form 1 September 2002  相似文献   

Observations of Phytophthora spp. in Water Recirculation Systems in Commercial Hardy Ornamental Nursery Stock     

Karin Themann  Sabine Werres  R. Lüttmann  H.-A. Diener 《European journal of plant pathology / European Foundation for Plant Pathology》2002,108(4):337-343

Samples of water and sediment were taken from drains, reservoirs and wells from four commercial hardy ornamental nurseries with water recirculation systems. The samples were taken on seven different dates throughout a single year from August 1994 to July 1995. The samples were screened for Phytophthora species using five different methods: direct plating, three bait tests (using lupin seedlings, apples and Rhododendron leaves) and a DAS-ELISA (double-antibody sandwich enzyme-linked immunosorbent-assay) with two antisera. In the nurseries with old water recirculation systems, Phytophthora species were detected in the drains and in the reservoirs. In the nursery with a new recirculation system, the pathogens were only present in the drains. None of the water samples from wells in any of the nurseries were contaminated. Phytophthora species were present in the water as well as in the sediment samples from drains and reservoirs. They were detected in the water recirculation systems irrespective of the season. The number of isolates increased about sevenfold between late summer and spring. At least 12 different Phytophthora species were identified: some isolates were previously unrecorded species. The epidemiology of the pathogens in outdoor water recirculation systems as well as the importance of the results for commercial nurseries is discussed.  相似文献   

Amino Acid Changes in Pepper mild mottle virus Coat Protein That Affect L 3 Gene-mediated Resistance in Pepper     

Hiroyuki HAMADA  Shigeharu TAKEUCHI  Akinori KIBA  Shinya TSUDA  Yasufumi HIKICHI  Tetsuro OKUNO 《Journal of General Plant Pathology》2002,68(2):155-162

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Secretion of Natural and Synthetic Toxic Compounds from Filamentous Fungi by Membrane Transporters of the ATP-binding Cassette and Major Facilitator Superfamily   总被引：4，自引：0，他引：4  

Ioannis Stergiopoulos  Lute-Harm Zwiers  Maarten A. De Waard 《European journal of plant pathology / European Foundation for Plant Pathology》2002,108(7):719-734

This review provides an overview of members of the ATP-binding cassette (ABC) and major facilitator superfamily (MFS) of transporters identified in filamentous fungi. The most common function of these membrane proteins is to provide protection against natural toxic compounds present in the environment of fungi, such as antibiotics produced by other microorganisms. In plant pathogenic fungi, these transporters can also be an important determinant of virulence on host plants by providing protection against plant defence compounds or mediating the secretion of host-specific toxins. Furthermore, they play a critical role in determining base-line sensitivity to fungicides and other antimycotic agents. Overexpression of some of these transporters can lead to the development of resistance to chemically-unrelated compounds, a phenomenon described as multidrug resistance (MDR). This has been observed in a variety of organisms and can impose a serious threat to the effective control of pathogenic fungi.  相似文献   

Identification of Resistance to Common Bacterial Blight Disease on Bean Genotypes Grown in Turkey     

Atilla Dursun  M. Figen Dönmez  Fikrettin Şahin 《European journal of plant pathology / European Foundation for Plant Pathology》2002,108(8):811-813

Common bacterial blight (CBB) in edible beans (Phaseolus vulgaris), incited Xanthomonas campestris pv. phaseoli, reduces bean yields and seed quality. The main objective of this study was to determine resistance to common bacterial blight in bean genotypes. Twenty-two bean genotypes grown in Turkey including common and snap bean cultivars/lines were collected from different parts of Turkey and tested for resistance against to Xanthomonas campestris pv. phaseoli strain MFD-11. All the common and snap bean lines/cultivars tested were moderately susceptible, susceptible or highly susceptible, except AG-7117 which was found resistant to Xanthomonas campestris pv. phaseoli. This is the first report of a resistance source in a common bean line (AG-7117) against Xanthomonas campestris pv. phaseoli.  相似文献   

Modelling spatio-temporal dynamics of herbicide resistance     

O RICHTER  P ZWERGER  & U BÖTTCHER 《Weed Research》2002,42(1):52-64

A mathematical model has been developed for the risk assessment of the spread of genes conferring herbicide resistance in plant populations. The model combines an age-and-stage-structured population dynamic model, a population genetic model and a model of spatial spread. This is achieved by embedding a local matrix population model into a cellular automaton model with raster cells as spatial units. The dynamics of each cell is determined by both its local dynamics and the interaction with neighbouring cells. The model is applied to the evaluation of management strategies to delay or even to prevent long-term evolution of resistance in an annual grass weed. The results show that the appearance and spread of resistant genes is a highly non-linear process exhibiting threshold phenomena, which occur for a wide range of parameters. The properties of the seed survival curve constitute the `genetic memory' of the system and thus determine its long-term dynamics. It is possible to delay the evolution of resistance by suspension of treatment, reduction in herbicide application rate and introducing fallow periods. Spatial spread from an infested plot is inhibited by leaving untreated strips between adjacent fields.  相似文献   

Variation in the development of secondary dormancy in oilseed rape genotypes under conditions of stress   总被引：6，自引：0，他引：6  

E J J Momoh  W J Zhou  & B Kristiansson† 《Weed Research》2002,42(6):446-455

Summary A substantial amount of seed is left in the fields before and during harvest of oilseed rape. Although this crop exhibits little or no primary dormancy, the absence of certain environmental cues that promote germination of imbibed seeds induces secondary dormancy. The work reported investigated the extent to which environmental stress conditions, including osmotic stress, low oxygen stress and anaerobiosis, induce secondary dormancy in oilseed rape, and examined the variation in development of secondary dormancy between and within genotypes. Osmotic stress was most effective in inducing dormancy. Anaerobic treatment produced very few dormant seeds, as did an atmosphere low in oxygen and high in nitrogen. The development of secondary dormancy under osmotic stress varied considerably between and within genotypes. Dormancy ranged from almost zero to about 60% for winter genotypes and about 85% for spring types. Within genotypes, variations occurred between seed lots and years of harvest. Temperature variations affected the percentage of dormant seeds. More dormant seeds were likely to be produced with incubation under water stress at 20 °C than at 12 °C. In winter genotypes, fewer dormant seeds were produced when incubation temperature and germination test temperatures differed. Thus, incubating at 20 °C and 12 °C, followed by germination tests at 20 °C and 12 °C, respectively, produced most dormant seeds. Also, in the winter genotypes, the potential development of secondary dormancy was positively correlated with the pattern and speed of germination of untreated seeds.  相似文献   

Effect of submergence and naproanilide application on the growth of hemp sesbania and rice     

Kangetsu Hirase  William T. Molin 《Weed Biology and Management》2002,2(2):116-119

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