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1.
C. J. Asjes 《European journal of plant pathology / European Foundation for Plant Pathology》1975,81(1-2):64-70
Several mineral-oil sprays used to curtail the spread of stylet-borne tulip breaking virus (TBV) in tulips ‘Elmus’ were tested. The similarly concentrated sprays prepared with summer oil, winter oil, Albolineum, and Asepthion oil, decreased the spread of TBV considerably. Control was improved by the more concentrated Albolineum sprays (2.5, 5, 10%), and spread was reduced more effectively, when variable quantities of emulsions providing good leaf coverage were used (2.5, 5%). The weight ratios of the bulb yields of plots given a 2.5% spray in all years and a 5% spray in 1972 and 1973 fluctuated closely (0–6%) around the value for the untreated plots, which was taken as 100. These ratios dropped by 11–19% after more concentrated sprays were used in variable quantities in 1971. Spraying was slightly more effective at weekly than at fortnightly intervals, but the weight ratios scarcely differed. Better control of TBV spread was obtained when spraying was started at the beginning of May; when started in June, the sprays were not effective. The weight ratios were not clearly influenced differentially except when spraying was begun in the first week of May. The efficacy of mineral-oil sprays is discussed in relation to tulips and lilies, with reference to comparable experiments. The application of mineral-oil sprays for curtailing TBV spread in commercial tulip culture is discussed. 相似文献
2.
苯肽胺酸对辣椒抗逆性及产量的影响 总被引：1，自引：1，他引：0
为明确植物生长调节剂苯肽胺酸对作物的生物学效应,以辣椒为供试植物,芸苔素内酯为对照药剂,研究了苯肽胺酸不同浓度处理对辣椒植株抗逆生理指标及产量的影响。结果表明:200.0 mg/L质量浓度的苯肽胺酸可显著提高辣椒植株的抗逆性,与空白对照相比,辣椒叶片中类黄酮、总酚以及游离脯氨酸含量分别提高了10.06%~21.19%、7.42%~16.95%以及8.46%~241.26%;丙二醛含量下降了28.58%~52.79%;超氧化物歧化酶（SOD）、过氧化物酶（POD）和过氧化氢酶（CAT）活性分别提高了2.31%~9.00%、4.20%~471.72%和34.98%~121.19%。200.0 mg/L的苯肽胺酸处理具有明显增产效果,与空白对照相比,产量增加了13.91%。研究表明,苯肽胺酸的生物学效应与芸苔素内酯类似,可诱导辣椒抗逆性增强,且具有一定增产效应。 相似文献
3.
辣椒是云南省主要经济作物之一,近年来病毒病尤其是正番茄斑萎病毒属病毒发病严重,影响了辣椒产量和品质。利用RT-PCR技术对从云南辣椒主产区采集的疑似感染正番茄斑萎病毒属病毒的25份辣椒样品进行分子鉴定,结果显示,12份样品检测出正番茄斑萎病毒属病毒,检出率为48.0%,其中6份是番茄斑萎病毒tomato spotted wilt orthotospovirus (TSWV),检出率为24.0%;5份是番茄环纹斑点病毒tomato zonate spot orthotospovirus (TZSV),检出率为20.0%;有1份是TSWV和TZSV复合侵染,检出率为4.0%,这是在云南辣椒生产上首次发现TSWV和TZSV的复合侵染。通过鉴定,初步了解正番茄斑萎病毒属病毒在云南辣椒生产中的发生情况和种类,为制定云南地区该属病毒的防治策略提供理论依据。 相似文献
4.
The effects of metham-sodium (MES) soil treatment, a varying number of benomyl foliar sprays (two, three and six) and combined treatments on control of lettuce drop disease were studied at two sites in Israel naturally infested with the pathogen Sclerotinia sclerotiorum. MES killed 85% of the S. sclerotiorum sclerotia in the top 10 cm of soil where initial populations were 0.6 and 1.6 viable sclerotia per kg soil at the two sites. Of the remaining viable sclerotia. only 30% produced apothecia. MES treatment alone reduced numbers of apothecia to 5% of those counted in the unsprayed control treatment. Numbers of ascospores deposited on the crop in the MES-treated plots were 7-20% of those deposited on control plots. Lettuce drop decreased the total yield by 30% in unsprayed control plots; MES application reduced the loss to 4% and also increased the number of marketable plants. Benomyl sprays alone also significantly reduced numbers of apothecia and disease development and consequently increased yield, although not to the extent observed with the MES treatment alone. Combined treatments produced the best disease control, but this improvement was not accompanied by any major increase in yield compared to that with MES treatment alone. 相似文献
5.
C. J. Asjes 《European journal of plant pathology / European Foundation for Plant Pathology》1991,97(3):129-138
The inhibitory effect on the spread of viruses in lilies viz., tulip breaking virus (TBV; nonpersistently aphid-borne, potyvirus,) lily symptomless virus (LSV; non-persistently alphidborne, carlavirus), and lily virus X (LVX; potexvirus of unknown etiology), was studied of brands of mineral oil (Luxan oil H and Duphar-7E oil) and synthetic pyrethroid insecticides (l-cyhalothrin and deltamethrin), and a nematicide (aldicarb) in crops in which virus-infected plants were present as virus sources. The spread of TBV and LSV were controlled by sprays of mineral oil and insecticide, while that of LSV was also limited by the soil-applied nematicide. The spread of LVX was reduced by the insecticides and, not effectively by the mineral-oil spraying, by which data the mode of transmission may be presumed to be by an insect in the persistent or semi-persistent manner.Mixtures of mineral oil and pyrethroid were more effective in the reduction of spread of TBV and LSV than either components tested alone. The mineral oil was the most effective component in the mixtures in which pyrethroid added a slight extra effect. The addition of pyrethroid did not mask either the lower efficacy of the oil brand Duphar-7E oil, or the diminished inhibitory effect of low dosages of oil. The normal rate of mineral oil gave similar control to that of a mixture of mineral oil at half rate plus the pyrethroid at full dosage. Low rates of oil, or even synthetic pyrethroids alone may be used on cultivars which suffer of the loss of bulb weight by the use of normal or decreased rates of oil. Weekly sprays were more effective than fortnightly sprays. The rate of control by the weekly sprays ranged between 90 and 95% for Luxan oil H at half dosage plus the full rate of pyrethroid. Weekly sprayed synthetic pyrethroids alone onto the virus sources and the plants to be infected gave 60–70% control. The weight ratios tended to be slightly reduced if the half dosage of the efficient Luxan oil H was used. Factors which affect the control of the air-borne field spread of viruses by mineral oils and synthetic pyrethroid insecticides in lilies are discussed. 相似文献
6.
NIHAT TURSUN IRFAN ERSIN AKINCI AHMET ULUDAG ZULEYHA PAMUKOGLU DOGAN GOZCU 《Weed Biology and Management》2012,12(2):109-115
Direct seeded red pepper is a cash crop in Kahramanmara? province of Turkey as well as some other nearby provinces. Weeds are a major constraint in red pepper production. Field studies were conducted to determine critical period for weed control (CPWC) in direct seeded spice pepper in Kahramanmara?, in 2008 and 2009. The CPWC in red pepper based on a 2.5%, 5% and 10% acceptable yield loss (AYL) was calculated by fitting logistic and Gompertz equations to relative yield data. The CPWC in red pepper was determined from 0 to 1087 growing degree days (GDD) in 2008 and from 109 to 796 GDD in 2009 for 10% AYL after crop emergence in red pepper. For 2.5–5% AYL, the CPWC starts with germination and lasts until harvest. Direct seeded red pepper is very vulnerable to weed competition and weed control programs for direct seeded spice pepper in Turkey should include pre‐emergence and residual herbicides. 相似文献
7.
Use of fungicides to control chocolate spot (Botrytis fabae) on winter field beans (Vicia faba) 总被引：1，自引：1，他引：0
Less chocolate spot (% leaf area affected) developed on winter–sown field beans sprayed with benomyl than on untreated beans or beans sprayed with iprodione, prochloraz or thiabendazole. A single benomyl spray during flowering reduced disease development and increased yield by 20% in 1982 when a severe chocolate spot epidemic developed in untreated plots during flowering. Benomyl sprays at flowering also increased yield in 1980 when there was less disease at flowering than in 1982, but did not increase yield in 1981 when there was little disease at flowering. In 1981 a severe chocolate spot epidemic developed early in the season and less chocolate spot developed on lower leaves of beans grown from seed treated with benomyl plus thiram than on beans grown from untreated seed. Treated plots yielded 70% more than untreated plots, although by early flowering there was no difference in chocolate spot between them. Seed treatment did not increase bean yields in 1982 and 1983, when chocolate spot did not develop early in the season. In the glasshouse, benomyl seed treatment prevented the development of aggressive lesions on lower leaves but thiram did not. 相似文献
8.
K. Andersson 《EPPO Bulletin》1984,14(3):409-416
The effects of increasing inputs of pesticides, nitrogen and growth regulators were studied in field trials in winter wheat and spring barley in southern Sweden. The trials also included a comparison of different strategies: no control, routine control and supervised control. In 1982 EPIPRE, a computerized pest and disease management system developed in the Netherlands, was included. High inputs of nitrogen only slightly influenced the yields. In winter wheat, routine control, comprising one insecticide and three fungicide sprays, heavily increased the yield and was more profitable than supervised control. On an average only 1.2 pesticide sprays were carried out in supervised plots. However, in spring barley supervised control was slightly more profitable than routine control comprising one fungicide and one insecticide application. The average number of sprays in supervised was 0.6 only. In both winter wheat and barley the yield increase for routine control significantly increased with increasing nitrogen level. In barley a significant relationship between number of aphids per tiller and yield increase could be proved. 相似文献
9.
Potato crops (cv. Alpha) were grown in walk-in plastic tunnels (33 m2 ) in winter 1987 and spring 1988. Crops were left untreated or treated (four sprays at intervals of 2 weeks) with either metalaxyl, Ridomil-MZ (metalaxyl+ mancozeb) or Ridocym (metalaxyl +mancozeb+cymoxanil). Crops were inoculated with sporangial suspensions of Phytophthora infestans containing 01, 1 or 10% metalaxyl-resistant sporangia. Disease progress and percentage resistant sporangia in tunnels were estimated for a period of 50 days. In the treated crops cumulative disease, rate of disease progress and increase in frequency of resistant phenotypes (selection coefficient) were higher in metalaxyl-treated crops than in Ridomil-MZ or Ridocym-treated crops. Cumulative disease, rate of disease progress and increase in frequency of resistant phenotypes were unaffected by the frequency of resistant sporangia in the original inoculum. Metalaxyl, Ridomil-MZ and Ridocym speeded up the selection for resistance by 92, 29 and 17%, respectively, relative to untreated crops. The time interval required for the resistant subpopulation to predominate in treated crops was inversely related to initial resistance. It was longest in crops inoculated with 0.1 % resistant sporangia and treated with Ridocym. Results indicated that metalaxyl mixtures were advantageous over metalaxyl alone, both in delaying the buildup of resistance and in improving disease control, but did not prevent resistant subpopulations increasing from 01 to 100% in a single season. 相似文献
10.
C. L. M. de Visser 《European journal of plant pathology / European Foundation for Plant Pathology》1996,102(8):795-805
Between 1988 and 1992 two existing weather based advisory models to control leaf blight in onions, were evaluated in the Netherlands. The first model, BOTCAST, can be used to time the initial spray while the second model, SIV, can be used to advise on every subsequent spraying. The evaluation based on field trials showed that application of both BOTCAST and SIV can reduce the number of sprays by 54% compared to a weekly spraying program without any yield loss or a higher disease severity. There was no relation between yield losses of untreated plots and disease severity expressed as lesion counts or leaf dieback. Relative disease growth rate was significantly but not closely related to weather based model characteristics or the observed crop micro-climate using linear regression analysis. The model characteristics did not yield better regressions than the climatological characteristics. Two changes to improve BOTCAST are proposed. Introduction of a supervised control system based on BOTCAST and SIV seems only economically feasible when the system is used as a regional warning system. 相似文献
11.
为明确不同除草措施对辣椒地杂草防除效果,采用田间小区试验方法,研究单独施用除草剂、地膜覆盖、除草剂+地膜覆盖不同除草措施对辣椒地杂草防除效果。结果表明,单用除草剂960 g/L精异丙甲草胺乳油、330 g/L二甲戊灵乳油对辣椒地杂草30 d群体株防效分别为68.75%、65.07%,60 d杂草群体株防效、鲜重防效分别为76.50%、82.88%,82.99%、87.35%。白膜覆盖、黑膜覆盖、白膜覆盖+960 g/L精异丙甲草胺乳油、白膜覆盖+330 g/L二甲戊灵乳油、黑膜覆盖+960 g/L精异丙甲草胺乳油、黑膜覆盖+330 g/L二甲戊灵乳油对辣椒地杂草30 d群体株防效均达97.00%以上,60 d群体株防效均达96.00%以上,鲜重防效除白膜覆盖+960 g/L精异丙甲草胺乳油处理外,均达93.00%以上。综合试验结果表明,地膜覆盖、除草剂+地膜覆盖均能较好地防除辣椒地杂草,实际生产应用中为减少农药使用可直接覆盖地膜防除辣椒地杂草。 相似文献
12.
赤眼蜂防治线辣椒烟青虫试验示范 总被引：2，自引：0，他引：2
在1600亩面积上试验,放蜂区烟青虫卵寄生率65～75％;百株残虫控制在1头左右;角果被害率压低到0.6～0.8;增产10～15％,干椒成品率提高15％;生防费用比化学农药费用障低75％。 相似文献
13.
14.
Variation in the response of cashew genotypes to the targeted application of fungicide to flower panicles for control of powdery mildew disease 总被引：1，自引：0，他引：1
Application of the fungicide triadimenol (Bayfidan) directly to inflorescences of cashew was investigated as a means of controlling powdery mildew disease caused by Oidium anacardii. Disease development and nut production were studied in 12 cashew genotypes that differed in their susceptibility to mildew. Panicle colonization by O. anacardii reached 100% coverage in all genotypes without fungicide treatment, but rates of infection differed significantly. Triadimenol sprays reduced mildew to less than 9%, even in panicles of highly susceptible genotypes. In the absence of disease, particularly good yield responses with more than nine times more nuts set than untreated controls were achieved by AM6 and AC1, which were categorized as highly susceptible and intermediate, respectively, in reaction to powdery mildew. By contrast, the partially resistant genotypes AZA2 and AC6 both produced yield response ratios of less than 3·0. The targeted treatment of flower panicles to control mildew is recommended, rather than the current practice of wastefully treating whole trees on which all mature leaves are naturally immune to infection. 相似文献
15.
蚜虫迁飞动态与辣椒病毒病流行的关系 总被引：4，自引：1，他引：4
在江苏省泰县和南京城郊辣椒病毒病的优势病原为黄瓜花叶病毒(CMV),次为烟草花叶病毒(TMV),此外还鉴定了一种蚕豆萎蔫病毒(BBWV)。辣椒病毒病发病株率随迁入辣椒田内有翅蚜总量的增长而增高,两者呈显著正相关,蚜虫迁飞高峰后20天左右出现辣椒发病高峰。田间最有效的传毒介体为桃蚜、萝卜蚜、禾谷缢管蚜,它们的迁飞高峰都在5月中、下旬,此时正值辣椒感病阶段,对发病率和产量影响较大。5月中旬至6月中旬置放田间的辣椒苗发病率最高,说明此时迁入田间的有翅蚜传毒最为有效,此期间是阻断蚜虫传毒的关键时期。 相似文献
16.
M D Amador-Ramírez 《Weed Research》2002,42(3):203-209
Summary Field experiments were conducted from 1991 to 1993 to determine the critical period of weed control in chilli pepper. The maximum weed-infested period ranged between 0.7 and 3.2 weeks after transplanting (WAT) at a 5% yield loss level. To prevent losses in total and marketable yields, weeds should be removed 2.1 or 0.9 WAT respectively. The end of the critical period decreased as the predetermined yield loss level increased from 2.5% to 10%. The minimum weed-free period ranged between 6.7 and 15.3 WAT at a 5% yield loss level depending on crop yield category. The chilli pepper crop required an average of 12.2 weeks of weed-free maintenance to avoid losses above 5%. Using a 5% yield loss level, the duration of the critical period of weed control was 14 weeks in 1991 and 11.2 weeks in 1993, but was shortened to 5.1 weeks in 1992. The results suggest that weeds must be controlled during the first half of the crop's growing season in order to prevent yield losses. 相似文献
17.
膜下滴灌条件下土壤基质势对辣椒产量和水分利用效率的影响 总被引：2，自引：0，他引：2
为了提高西北干旱地区作物的水分利用效率,研究了膜下滴灌条件下,不同土壤基质势对辣椒产量、耗水和水分利用效率的影响。试验根据滴头下25 cm深处土壤的基质势设置5个控水下限:-10、-20、-30、-40kPa和-50 kPa,测量指标主要有气象要素、土壤水分特性曲线、土壤基质势、土壤水分、辣椒产量和单果重等。试验结果表明,基质势下限控制在-10～-40 kPa之间对产量影响较小,但是当基质势下限降至-50 kPa时会导致严重减产,灌水量与辣椒腾发量一般随着基质势控制下限的降低而逐渐减少,水分利用效率随着基质势控制下限的降低呈现先升高再降低的趋势。土壤基质势下限控制在-30～-40 kPa时辣椒产量和水分利用效率均较高,因此建议在西北干旱地区膜下滴灌条件下辣椒的基质势控制下限宜为-30～-40 kPa。 相似文献
18.
A. Ouattara F. Tiendrébéogo P. Lefeuvre M. Hoareau S. Claverie A. Allibert F. Chiroleu E.V. Traoré N. Barro O. Traoré J.-M. Lett 《Plant pathology》2020,69(2):379-392
In West and Central Africa, as in many regions of the world, vegetables are severely affected by geminivirus diseases. In Burkina Faso, observation of various virus-like symptoms, especially on tomato, suggests the involvement of several geminiviruses and underlines the pressing need for additional information on their diversity, distribution, prevalence and host plant reservoirs. Large-scale surveys conducted in Burkina Faso confirmed the presence of tomato (yellow) leaf curl diseases (ToLCD-TYLCD) and geminiviruses in all localities with mean prevalences of 25% and 45%, respectively. Five geminiviruses including four begomoviruses (pepper yellow vein Mali virus (PepYVMLV), tomato leaf curl Burkina Faso virus, tomato leaf curl Mali virus and tomato leaf curl Ghana virus) and a dicot-infecting mastrevirus (chickpea chlorotic dwarf virus) were characterized on tomato. In addition, PepYVMLV and cotton leaf curl Gezira virus (CLCuGeV) were characterized on pepper and okra, respectively, in combination or not with alphasatellites and betasatellites for CLCuGeV. The most severe, prevalent and widely distributed virus on vegetables was PepYVMLV, which was characterized for the first time in combination with a genetically divergent DNA-B component that may constitute a key factor of PepYVMLV pathogenicity. Of the eight weeds identified as potential reservoir hosts of begomoviruses, four host PepYVMLV. The results confirm the importance of geminivirus diseases on vegetable crops in Burkina Faso and highlight the complex association of geminiviruses and satellites. The detection of begomoviruses in weeds growing close to crops points to the increasing necessity to consider reservoir plants and virus communities in the control of virus diseases. 相似文献
19.
Genetic diversity and mixed infections of begomoviruses infecting tomato, pepper and cucurbit crops in Nicaragua 总被引：1，自引：0，他引：1
M. Ala-Poikela E. Svensson ‡ A. Rojas T. Horko L. Paulin J. P. T. Valkonen A. Kvarnheden † 《Plant pathology》2005,54(4):448-459
Begomoviruses were detected in Nicaraguan fields of tomato ( Lycopersicon esculentum ) and adjacently growing plants of pepper ( Capsicum annuum ), chilli pepper ( C . baccatum ), cushaw ( Cucurbita argyrosperma ) and Mexican fireplant ( Euphorbia heterophylla ) using polymerase chain reaction (PCR) and universal begomovirus primers. All tomato and Mexican fireplant plants showing symptoms were infected with begomoviruses, while only 30–46% of the pepper, chilli pepper and cushaw plants showing symptoms tested virus-positive. No begomoviruses were found in potato. The virus species were provisionally identified by sequencing 533 bp of the viral coat protein gene ( AV1 ). Tomato severe leaf curl virus (ToSLCV), Tomato leaf curl Sinaloa virus (ToLCSinV) and Pepper golden mosaic virus (PepGMV) were found to infect both tomato and pepper. A new provisional species designated Tomato leaf curl Las Playitas virus (ToLCLPV) was detected in a tomato plant. Squash yellow mottle virus (SYMoV) and PepGMV were found in cucurbits, the latter for the first time in this host. Euphorbia mosaic virus (EuMV) was detected in Mexican fireplant. Sequencing of a larger number of PCR-amplified clones from selected plants revealed intraspecific viral sequence variability, and also multiple begomovirus infections which could represent up to three species in a single tomato or cushaw plant. Phylogenetic grouping of virus sequences did not correlate with the host of origin. 相似文献
20.
本研究提取野生食用菌——花脸蘑Lepista sordida的蛋白粗提液,并在室内测定其对辣椒病毒病的控制作用及其对辣椒植株生长的促进作用。结果表明,以25、50和100μg·mL^-1的花脸蘑蛋白粗提液分别茎叶喷雾处理后再接种黄瓜花叶病毒,防治效果分别为72.11%、79.53%和94.86%;以100μg·mL^-1的花脸蘑蛋白粗提液通过茎叶喷雾,浸种与茎叶喷雾结合两种方法处理辣椒后,辣椒根系的湿重及干重、辣椒地上部湿重和干重、叶片数、叶面积、叶绿素指数、株高、茎粗和壮苗指数均比对照明显提高。综上所述,花脸蘑蛋白粗提液在室内对黄瓜花叶病毒引起的辣椒病毒病有很好的控制作用,同时对辣椒生长具有良好的促进作用。 相似文献