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1.
In carnations grown on rockwool disease incidence of fusarium wilt caused byFusarium oxysporum f.sp.dianthi (Fod) was reduced when Fe-EDDHA instead of Fe-DTPA was used as iron source in the nutrient solution. Addition ofPseudomonas sp. strain WSC417r intensified this reduction in the cultivar Pallas, moderately resistant to Fusarium, but not in the susceptible cultivar Lena. Treatment of plants with Fe-EDDHA instead of Fe-DTPA as iron source resulted in higher numbers and percentages on the roots, ofin vitro antagonistic fluorescent pseudomonads. However, differences were only significant at 56 days after planting for cv. Lena and at 14 and 28 days after planting for cv. Palas. Both chelators, at different concentrations, had no effect on root colonization by eitherPseudomonas sp. strain WCS417r orFod strain WCS816. However, when coinoculated, reduced numbers of propagules ofFusarium were found at concentrations of Fe-EDDHA lower than 10–5 M.Higher concentrations of the siderophore fusarine produced byFod strain WCS816 were demonstrated when Fe-EDDHA instead of Fe-DTPA was used as iron source in culture media. At equal concentrations, no such differences were found in the amount of siderophore produced by WCS417r. Germ tube length ofFod was less with Fe-EDDHA than with Fe-DTPA. The reduction of germ tube length was stronger when the purified siderophore of WCS417r was added in excess to the culture media with Fe-EDDHA than those with Fe-DTPA. Therefore, the observed reduction of germ tube growth can not completely be explained by iron deprivation. It appeared that EDDHA exhibited a toxic effect for conidia ofFod strain WCS816 as well.we conclude that the observed disease reduction by Fe-EDDHA is a consequence of a limitation of iron availability forFod. This limitation is possibly intensified by the increase in number or percentage of antagonistic fluorescent pseudomonads that strongly compete for iron. The additional effect after bacterization withPseudomonas strain WCS417r in Fe-EDDHA treated carnations of cv. Pallas is likely to be due, at least partly, to a direct competition for iron between the siderophores ofFod strain WCS816 and ofPesudomonas sp. strain WCS417r.Samenvatting Verwelkingsziekte in anjers op steenwol, veroorzaakt doorFusarium oxysporum f. sp.dianthi (Fod), werd gereduceerd indien het ijzer-chelaat Fe-EDDHA in plaats van Fe-DTPA werd toegevoegd aan de nutriëntenvloeistof. Bacterisatie metPseudomonas sp. stam WCS417r had een additioneel effect bij de matig resistence cultivar Pallas maar niet bij de vatbare cultivar Lena. Toevoeging van Fe-EDDHA in plaats van Fe-DTPA aan planten als ijzerbron resulteerde op de wortels in hogere aantallen en percentages fluorescerende pseudomonaden, diein vitro antagonistisch waren ten opzichte vanFod. De verschillen waren echter alleen significant 56 dagen na planten voor de cultivar Lena en 14 en 28 dagen na planten voor de cultivar Pallas. Beide chelaten vertoonden bij verschillende concentraties geen effect op de kolonisatie van de wortel door beide microorganismen. Echter, wanneer beide micro-organismen gezamelijk werden toegevoegd nam de wortelkolonisatie doorFod stam WCS816 af bij concentraties lager dan 10–5 M Fe-EDDHA. Er werd meer van het siderofoor fusarine doorFod stam WCS816 geproduceerd bij concentraties lager dan 10–4 M Fe indien Fe-EDDHA in plaats van Fe-DTPA als ijzerbron aan het cultuurmedium was toegevoegd. Er werd geen effect van beide chelaten gevonden op de siderofoorproduktie door WCS417r. Indien een overmaat van het gezuiverde siderofoor van WCS417r werd toegevoegd aan Fe-EDDHA werden een sterkere afname van de kiembuislengte gevonden dan toevoeging aan Fe-DTPA. De reductie van de kiembuislengte bleek niet volledig verklaard te kunnen worden door een afname van de ijzerbeschikbaarheid. Het chelaat EDDHA heeft ook een toxisch effect op conidiën van fusarium.Wij concluderen, dat de waargenomen reductie van de verwelkingziekte door Fe-EDDHA een gevolg is van de afname van de ijzerbeschikbaarheid voorFod. Dit wordt waarschijnlijk versterkt door de ontwikkeling van een antagonistische, fluorescerendePseudomonas-populatie die sterk concurreren om ijzer. Het additioneel effect dat door bacterisatie metPseudomonas sp. WCS417r van de met Fe-EDDHA behandelde matig resistante anjers (Pallas) werd verkregen is voor een deel het gevolg van een directe concurrentie om ijzer tussen de sideroforen vanFod stam WCS816 en vanPseudomonas sp. stam WCS417r.  相似文献   
2.
To improve genetic gain of breeding programs for village poultry production, breeding schemes with observations obtained in village production systems using individual (VIO) and group recording (VGO) were examined under different levels of genotype-by-environment-interactions (GxE). GxE was modeled by varying the correlation between traits measured in the breeding station and village environments for bodyweight (rg_BW) and egg production (rg_EP). Relative and absolute genetic gains obtained from VIO and VGO were used for comparison between the schemes. Results showed that village observations significantly improved genetic gains compared to the scheme without birds tested in the village. The improvement was only slightly larger with individual observations than with group observations. Higher rg_BW and rg_EP led to lower relative genetic gain, but a higher absolute gain of VIO and VGO. It is recommended to apply a breeding scheme using group recording of village performance when strong GxE in breeding for village poultry is expected.  相似文献   
3.
徐同 Peer  R 《植物病理学报》1989,19(3):179-184
 本文报道萤光假单胞菌(fluorescent Pseudomas spp.) WCSX 13.WCS 417andWCS 358在水培系统中香石竹根部的定殖及其对香石竹镰刀菌枯萎病的抑制作用。细菌处理两周后,WCS 417在感病品种Lena和中抗品种Pallas根部的定殖分别为8.8×102cfu/cm和9.8×102cfu/cm,而WCS 358分别为0.9×102cfu/cm和0.13×102cfu/cm。在通气的三角瓶中水培的Pallas品种,人工接种病原菌香竹石尖镰孢Fusarium oxyspotum f.sp.dianthi (Prill.&Del.) Snyd.&Hans.(Fod)6周后,用WCSX·13和WCS 417根部处理的病指分别为0.19和0.31,未细菌处理的对照为0.58,细菌处理植株的根部及茎内组织的病原菌种群密度低于对照。营养膜技术(NFT)栽培的Lena品种,WCS 417细菌处理的发病率比对照减少13%。  相似文献   
4.
Controlled-release formulations of 14C-labelled thiobencarb herbicide were prepared in calcium alginate using kaolin as an inexpensive filler. The rates of release of the herbicide from these and from a commercial granular formulation were studied in static distilled water contained in open and closed vessels. The rate of release of the herbicide was much higher from the commercial formulation than from the controlled-release formulations. Increasing the proportion of kaolin to calcium alginate in controlled-release formulations reduced the rate of release of the herbicide. There was a significant loss of thiobencarb-related radioactivity from the water solution when the vessels containing the solutions were left uncovered and exposed to light. The loss of the herbicide seemed to be due to degradation and evaporation.  相似文献   
5.
The variations with breed, gender, age and coat colour in the prevalence of Culicoides hypersensitivity were studied in 408 horses on 18 farms in Israel. Data were gathered by means of questionnaires and the diagnoses were confirmed by direct physical examinations. The prevalence of Culicoides hypersensitivity was 28 per cent. The disease was rare on farms more than 800 m above sea level but was more prevalent at lower altitudes. The most important factors affecting the prevalence of Culicoides hypersensitivity were the farm, breed and age, but gender and colour were not significantly correlated with its prevalence.  相似文献   
6.
The reed forests that are the subject of this study are scattered over five thanas of the Sunamganj and Sylhet Districts of the Sylhet Division of Bangladesh. Their total area is 23,590 ha and they have great ecological, economic, commercial and socio-economic importance due to the diversified resources they supply. However, the forests are commonly encroached on by local people who are perceived to be seriously depleting the resource. This paper deals with the socio-economic status of the people residing near these reed forests, and examines their dependency on the resources provided by the reed forests. A socio-economic survey, participatory rural appraisal and interviews were used to obtain baseline data of the reed forest resource and the local communities. The study reveals that the communities in the study region have higher income than other areas of Bangladesh. Most survey respondents have other occupations in addition to farming. The literacy rate is 28.8%. Among the illiterate, 68% engage in collecting reeds. Although the Forest Department has a management plan for sustainable use of the reed forests, encroachers receive backing from political leaders and local elites, so their eviction is difficult. In order to achieve long-term productivity and sustainability from the reed forests, this study recommends a strategy of developing an integrated joint management plan between the Forest Department and the local people.  相似文献   
7.
Zusammenfassung Die wichtigsten Milben von wirtschaftlicher Bedeutung im Libanon, Jordanien und der südlichen Türkei werden aufgeführt. Es handelt sich auf Äpfeln um:Tetranychus urticae, Metatetranychus ulmi, Tetranychus cinnabarinus, Bryobia rubrioculus; aufCitrus sp. um:Phyllocoptruta oleivora, Aceria sheldoni ,Eutetranychus orientalis, Brevipalpus obovatus, T. cinnabarinus: auf Gemüsearten um:Tetranychus urticae, T. cinnabarinus; auf Wein um:Eriophyes vitis; auf Granatäpfeln um:Eriophyes granati.Die Orte und Daten der Befunde werden angegeben.
Summary The mites of economic importance in the Lebanons, Jordan and South-Turkey are listed with the dates and places in which they were found. On apples were found:Tetranychus urticae, Metatetranychus ulmi, Tetranychus cinnabarinus, Bryobia rubrioculus; onCitrus sp.: Phyllocoptruta oleivora, Aceria sheldoni, Eutetranychus orientalis, Brevipalpus obovatus, T. cinnabarinus; on vegetables:T. cinnabarinus, Tetranychus urticae; on vines:Eriophyes vitis; on pomegranates:Eriophyes granati.

Résumé Les acariens d'une importance èconomique au Liban, en Jordanie et au sud de la Turquie sont donné avec les dates et les endroits où ils ont ètè trouvés. Sur pommiers on a trouvé:Tetranychus urticae, Metatetranychus ulmi, Tetranychus cinnabarinus, Bryobia rubrioculus; sur agrumes:Phyllocoptruta oleivora, Aceria sheldoni, Eutetranychus orientalis, Brevipalpus obovatus, T. cinnabarinus; sur légumes;Tetranychus urticae, T. cinnabarinus; sur les vignes:Eriophyes vitis; sur les grenades:Eriophyes granati.
  相似文献   
8.
Y. Kowyama  T. Saba  T. Tsuji  T. Kawase 《Euphytica》1994,80(1-2):27-38
Summary Developmental stages during gametogenesis of rice were histologically examined in the period from differentiation of reproductive organs to anthesis. Plants were exposed to acute X-rays of 20 Gy. Radiosensitivity and mutation frequency were investigated in relation to the developmental stages of reproductive organs. The most radiosensitive stage, as measured by reduction of the M1 pollen-and seed-fertilities, was the last premeiotic interphase. Mutations induced at different developmental stages were scored in M3 strains. Sterility mutants and short-culm mutants were most frequently observed. Grain shape, panicle morphology, heading-date and endosperm character mutants were induced at a relatively low frequency. The overall mutation frequency varied with the developmental stage at the time of irradiation. The highest overall mutation frequency was observed when radiation was applied 10 days before anthesis, the late tetrad stage of microspores. Radiation exposure of florets at the late tetrad stage was found to be a more efficient method of inducing a large number of mutations than radiations applied to seeds and fertilized egg cells.  相似文献   
9.
Fluconazole resistance is becoming an important clinical concern. We studied the in vitro effects of cinnamaldehyde against 18 fluconazole-resistant Candida isolates. MIC90 of cinnamaldehyde against different Candida isolates ranged 100–500 μg/ml. Growth and sensitivity of the organisms were significantly affected by cinnamaldehyde at different concentrations. The rapid irreversible action of this compound on fungal cells suggested membrane-located targets for its action. Insight studies to mechanism suggested that cinnamaldehyde exerts its antifungal activity by targeting sterol biosynthesis and plasma membrane ATPase activity. Inhibition of H+-ATPase leads to intracellular acidification and cell death. Toxicity against H9c2 rat cardiac myoblasts was studied to exclude the possibility of further associated cytotoxicity. The observed selectively fungicidal characteristics against fluconazole-resistant Candida isolates signify a promising candidature of this essential oil as an antifungal agent in treatments for candidosis.  相似文献   
10.
A new taxoid Taxawallin I (1) along with two known taxoids (2-3) were isolated from methanolic bark extract of Taxus wallichiana Zucc. Structural characterization was confirmed by mass and NMR spectral techniques. Taxawallin I exhibited significant in-vitro anticancer activity against HepG2, A498, NCI-H226 and MDR 2780AD cancer lines. Tubulin binding assay was performed to assess its tubulin binding activity. Molecular docking analysis was performed to study the potential binding mode inside the taxol binding site of β-tubulin.  相似文献   
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