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ROY K. NISHIMOTO 《Weed Biology and Management》2001,1(4):203-208
Purple nutsedge ( Cyperus rotundus L.) tubers remain viable for several years and serve as its principal means of survival. The maintenance of high moisture content is essential to tuber survival. Apical dominance influences bud dormancy within a tuber and in a chain of tubers, and dormancy increases with tuber age. Several growth inhibitors were identified in tubers, but their role in tuber dormancy has not been established. Moisture levels in soil must increase to a critical level before sprouting occurs, but excess soil moisture deters sprouting. Oxygen may be a limiting factor for tuber sprouting in waterlogged soils. Although light is not a requirement for sprouting, it has promoted sprouting. Temperature regulates sprouting; no sprouting occured below 10°C and above 45°C. Optimum sprouting occurred between 25 and 35°C when provided with constant temperatures. However, daily alternating temperatures greatly stimulated sprouting. A daily short duration (0.5 h) of high temperature increased sprouting to nearly 100%, whereas less than 50% sprouting occurred without the daily high temperature pulse. Bud break occurred readily for most tubers at 20°C and in nearly 100% of the tubers with a single 0.5 h exposure to a high temperature (35°C) pulse. However, most buds did not elongate if the tuber remained at 20°C. Bud elongation occurred at higher temperatures, and daily alternating temperatures stimulated shoot elongation up to eightfold greater than at the respective mean constant temperatures. Daily soil temperature fluctuation may be a major signal for purple nutsedge emergence, such as when the plant canopy is removed, or when soils are solarized. Future research is needed to determine tuber sprouting for different ecotypes, and on the role of the rhizome chain. Systems to manipulate sprouting may provide new strategies for purple nutsedge management. 相似文献
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《EPPO Bulletin》2011,41(3):394-399
Specific scope
This standard describes a national regulatory control system for Potato spindle tuber viroid (PSTVd) that provides guidance on preventing its introduction, surveillance for the pathogen and its containment and eradication if found infecting potato plants or tubers.Specific approval and amendment
First approved in 2011‐09. 相似文献5.
TATSUYA INAMURA 《Weed Biology and Management》2003,3(1):1-7
The loss of final tuber weight of Eleocharis kuroguwai Ohwi by shading during the early tuber formation period (TFP) is overcome by exposure to unshaded daylight thereafter (late TFP). In the present study, the growth parameters that contribute to the dry matter increase (DMI) per day of tubers in the late TFP were examined. DMI of the tuber during the late TFP was determined by that of the whole plant and the ratio of the DMI of the tuber to that of the whole plant during this period. The ratio of the DMI of the tuber to that of the whole plant during the late TFP was significantly correlated with the DMI of the whole plant during the first 14 days of the late TFP. During the late TFP after the exposure to unshaded daylight, DMI of the whole plant correlated with the surface area of the stem (SAS) and net assimilation ratio (NAR), and the SAS correlated with the stem dry weight (DW) and specific stem-surface area (SSA). SSA negatively influenced NAR, but NAR was increased by unshading. During the late TFP after shading, the effect of the decrease of the stem DW due to shading on the DMI of the whole plant was mitigated by the large SAS and high NAR. These results indicate that the growth parameters that contribute to the DMI of tuber during the late TFP after exposure to unshaded daylight are SAS and NAR just after unshading, and SSA during this period. 相似文献
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J. A. De Bokx P. G. M. Piron 《European journal of plant pathology / European Foundation for Plant Pathology》1981,87(2):31-34
Aulacorthum solani (Kaltenbach),Macrosiphum euphorbiae (Thomas) andMyzus persicae (Sulzer) were used for transmission experiments in laboratory and glasshouse. As inoculum served PSTV-containing tomato foliage and artificial diets containing purified PSTV. It is concluded thatM. euphorbiae can transmit PSTV in a non-persistent way.Samenvatting Aardappelspindelknolviroïde (PSTV) wordt tot een vrij nieuwe groep van pathogenen, de viroïden, gerekend. De ziekte, die er door wordt veroorzaakt, wordt sedert 1923 waargenomen in Noord-Amerika en is meer recentelijk ook aangetroffen in Afrika, Australië, Sowjet-Unie en Zuid-Amerika maar tot dusver niet in West-Europa.PSTV kan gemakkelijk mechanisch worden overgebracht. De overdracht door bladluizen was nog niet betrouwbaar vastgesteld. De bladluissoortenMyzus persicae (Sulzer),Aulacorthum solani (Kaltenbach) enMacrosiphum euphorbiae (Thomas) zijn daarom in overdrachtsproeven betrokken, waarbij als inoculum met PSTV geïnfecteerd blad en een door een membraan afgesloten gezuiverde PSTV-bevattende suspensie is gebruikt. Het laatstgenoemde type inoculum is gebruikt, om een mogelijke mechanische overdracht bij het overzetten van bladluizen van de viroïdebron naar de toetsplant tomaat cv. Sheyenne uit te sluiten. Er is vastgesteld, datM. euphorbiae PSTV op non-persistente wijze kan overbrengen. 相似文献
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L. Algera Afke C. van der Burg N. J. Fokkema 《European journal of plant pathology / European Foundation for Plant Pathology》1967,73(4):105-111
Potato tubers cut into halves were inoculated with conidial spores or mycelium ofGibberella zeae in order to study the permeability of the cells adjacent to and at some distance from the tissue invaded by the fungus. Permeability was determined by measuring the exosmosis rate of electrolytes. Within three days of infection the permeability of cells at a mean disease of 3 1/2 mm from the margin of the invaded tissue had doubled. At a mean distance of 6 mm there was no increase of permeability, except, perhaps, of a very slight increase 6 to 8 days after infection. A possible cause of the increase of permeability and its relation to the increased respiration are discussed. 相似文献
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为探明沟垄覆膜种植方式及贮藏温度对连作马铃薯品质的影响,以当地主栽品种“新大坪”为试验材料,研究了平畦不覆膜（CK）、平畦覆膜（T1）、全膜垄播（T2）、全膜沟播（T3）、半膜垄播（T4）、半膜沟播（T5）6种种植方式连作下马铃薯在不同贮藏温度下薯块品质特性的变化规律。3年大田连作试验结果表明,T2和T4薯块干物质、淀粉、还原糖、可溶性蛋白、氨基酸和Vc含量均显著高于其他处理;2014年与2013年相比,5℃贮藏条件下各种植方式薯块干物质、淀粉、还原糖、可溶性蛋白、氨基酸、Vc含量均增加,而有机酸含量降低;各处理在1℃贮藏条件下薯块干物质、淀粉、还原糖、可溶性蛋白、氨基酸和Vc含量均高于5℃,而有机酸含量则较低。连作条件下,垄播种植（T2、T4）有利于马铃薯贮藏品质的提高,且以1℃贮藏温度更有利于保持较高薯块品质。 相似文献
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甘肃省马铃薯坏疽病病原鉴定 总被引：1，自引：0，他引：1
本文通过Koch’s法则以及形态学和分子生物学方法对甘肃省兰州市马铃薯坏疽病进行病原鉴定。从马铃薯坏疽病标样中分离得到5株形态特征一致的产生分生孢子器的腔孢纲真菌,其代表菌株GSAA-0232对马铃薯块茎具有强的致病性,用该菌接种马铃薯块茎,可引起与自然发病相同的坏疽病症状。该菌的培养物生成代谢物"E"(NaOH斑反应显示出特有的紫红色)。利用引物Phoma-2/Phoma-7可扩增出474bp的Phoma foveata特异条带。根据其形态特征、生物学特性、致病性及分子生物学鉴定结果 (GenBank登录号:JQ963624),将菌株GSAA-0232鉴定为Boeremia foveata(Foister)Aveskamp,Gruyter&Verkley。这是Boeremia foveata引起马铃薯坏疽病在我国的首次报道。 相似文献
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Z. Basky 《Anzeiger für Sch?dlingskunde》2003,76(3):83-88
An aphid and virus survey was conducted from 1993 and 1999 on the eastern lowlands in Hungary. Aphid flight was monitored with two yellow pan traps placed on the edge and in the middle of seed potato fields. From 1993 and 1997, aphid flight was monitored with a Rothamsted type suction trap. The aphid and virus survey was continued in four different regions of Hungary in 2000. Aphid flight activity recorded by the suction trap and the yellow pan traps was different. Cumulative vector intensity based on yellow pan trap catches revealed a greater variation between years than among the different locations. In 4years out of 8, aphid flight was less intensive and quality seed potato was harvested regardless of the production site. Cumulative vector intensity is a good means to forecast the time of haulm destruction in seed potatoes. 相似文献
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马铃薯块茎病原真菌拮抗菌株筛选及优良拮抗菌株鉴定 总被引：1，自引：0，他引：1
从马铃薯块茎上分离内生细菌,以块茎病原真菌为指示菌,采用平板对峙法筛选拮抗菌株,并利用形态学特征和16S rDNA基因序列分析对优良拮抗菌株进行鉴定。结果表明,从定西马铃薯块茎中共分离得到72株内生细菌,其中19株对5种块茎病原真菌的抑菌率均高于51.87%,特别是内生细菌6-5和5-6分别对马铃薯炭疽病菌Colletotrichum coccodes和马铃薯黑痣病菌Rhizoctonia solani的抑菌率达85.82%和72.18%,且具有固氮和产吲哚乙酸(IAA)功能,其产IAA量分别为3.37 mg/L和19.25 mg/L;根据形态特征及16S rDNA基因序列将菌株5-6鉴定为萎缩芽胞杆菌Bacillus atrophaeus,菌株6-5鉴定为贝莱斯芽胞杆菌Bacillus velezensis。 相似文献
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广东省马铃薯块茎软腐病病原菌鉴定 总被引：1，自引：0，他引：1
为明确广东省惠州市马铃薯块茎软腐病的病原菌,采用常规病组织分离法获得4株菌株,通过生理生化特征和分子生物学特性对其进行鉴定,并测定了该病原菌对20个马铃薯品种的致病力。结果显示,该病原菌为革兰氏阳性菌,在LB平板上菌落有透明和不透明2种形态;除葡萄糖发酵阳性、对链霉素和青霉素具有抗性等特征不同外,BP-hd-1、BP-hd-2、BP-hd-3和BP-hd-4菌株与短小芽胞杆菌Bacillus pumilus菌株的其它生理生化特征均相同。系统进化分析结果表明,4株菌株的16S rDNA序列分别与短小芽胞杆菌AI-Khrj18(KY123871)、ML270(KC692158)、NCTC10337(LT906438)和ARD21(KX023236)的相似性为100.0%;4株菌株的gyrB基因序列均与短小芽胞杆菌AUEC29菌株(HM585095)的gyrB基因相似性最高,为99.7%～99.8%。生理生化特征及分子生物学鉴定结果表明,引起广东省马铃薯块茎软腐病的病原菌为短小芽胞杆菌。致病力测定结果显示,接种菌株BP-1后20个马铃薯品种的发病率均为100.0%,表明该病原菌对马铃薯有强致病力。 相似文献
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Detection of chrysanthemum stunt and potato spindle tuber viroids by polyacrylamide gelelectrophoresis 总被引：1，自引：0，他引：1
W. H. M. Mosch H. Huttinga F. A. Hakkaart J. A. De Bokx 《European journal of plant pathology / European Foundation for Plant Pathology》1978,84(3):85-93
Stunt viroid can be detected in chrysanthemums with the polyacrylamide gelectrophoresis (PAGE) method developed by Morris and Smith (1977) for potato spindle tuber viroid. The time of sample preparation can even be shortened considerably. The reliability of the short and the complete PAGE method proved to be similar to that of the biological Mistletoe test in a parallel experiment. Combined samples can be tested in the complete PAGE method easily permitting the detection of one diseased chrysanthemum top in a total of ten.Although potato spindle tuber viroid is not known to occur in the Netherlands we searched for methods to detect possible infections. Artificial infections of tomato and potato plants and of sprouts of potato tubers could readily be detected by Morris and Smith's method. Using this method it was possible to demonstrate infections by severe and weak isolates even when not yet producing symptoms. In tomato plants the viroid could be detected four to eight days before symptoms appeared.Samenvatting Het dwergziekteviroïde (CSV) kon in chrysanten worden aangetoond met een door Morris en Smith (1977) voor het aardappelspindelknolviroïde (PSTV) ontwikkelde polyacrylamide-gelelektroforesemethode (PAGE). Het bereiden van de monsters voor elektroforese kon evenwel aanzienlijk worden vereenvoudigd. De volledige, evenals de korte PAGE-methode bleek even betrouwbaar als de biologische Mistletoe-toets. De PAGE-methode was zo gevoelig dat toepassing ervan op mengmonsters verantwoord is: één besmette top van een chrysantheplant in een totaal van tien kon nog betrouwbaar worden aangetoond.Howewel het PSTV niet in Nederland voorkomt, werden de mogelijkheden onderzocht om infecties met dit viroïde te kunnen vaststellen. Kunstmatige infecties met het viroïde in tomate- en aardappelplanten en in aardappelspruiten konden met de door Morris en Smith beschreven PAGE-methode worden aangetoond. Dit gold zowel voor sterke als voor zwakke isolaten, ook als ze geen symptomen veroorzaken. In tomaat kon met de PAGE-methode het PSTV al vier tot acht dagen vóór de symptomen verschenen worden aangetoond. 相似文献
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Z. Basky 《Anzeiger für Sch?dlingskunde》2003,98(Z2):83-88
An aphid and virus survey was conducted from 1993 and 1999 on the eastern lowlands in Hungary. Aphid flight was monitored with two yellow pan traps placed on the edge and in the middle of seed potato fields. From 1993 and 1997, aphid flight was monitored with a Rothamsted type suction trap. The aphid and virus survey was continued in four different regions of Hungary in 2000. Aphid flight activity recorded by the suction trap and the yellow pan traps was different. Cumulative vector intensity based on yellow pan trap catches revealed a greater variation between years than among the different locations. In 4years out of 8, aphid flight was less intensive and quality seed potato was harvested regardless of the production site. Cumulative vector intensity is a good means to forecast the time of haulm destruction in seed potatoes. 相似文献
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F. P. Geels J. G. Lamers O. Hoekstra B. Schippers 《European journal of plant pathology / European Foundation for Plant Pathology》1986,92(6):257-272
The effects of a seed tuber treatment with antagonistic isolates of fluorescentPseudomonas spp. were investigated on potato plants from 1981 to 1984. The experimental plots were located in fields in short and long rotations of potato. The short rotations are characterized by serious yield reductions which are caused by unknown microbial factors. The reductions varied from 30% in 1982 to only 3% in 1983 in the 3-year rotations. A statistically significant increase in yield (four to five months after planting) of ware potatoes varying from 9 to 20% was obtained in these plots through tuber bacterization, but only in 1981. In 1982 and 1983 initially significant improvements in shoot or tuber weight of seed potatoes were no longer detectable at ware potato harvest at the end of the growing period. Seed tuber bacterization had no effect on tuber yield in long rotations. Initial colonization of basal root parts by 53×104 colony forming units (cfu) of antibiotic-resistant mutants per gram of root (fresh) dropped significantly to 20×104 cfu per gram after three months. The bacterization effect on tuber yield depended on the development of harmful microbial activity and of introduced antagonists during the growing period. Seed tuber bacterization is more promising for seed potatoes than for ware potatoes in short rotations, the latter being harvested two months later.Samenvatting De invloed van pootgoedbehandeling met antagonistische isolaten van fluorescerendePseudomonas-soorten op de aardappelteelt, werd onderzocht in de periode van 1981 tot en met 1984. De proefvelden maakten deel uit van zowel ruime als nauwe rotaties met aardappelen. Kenmerkend voor de nauwe rotatie is, dat de opbrengst aanzienllijk gereduceerd wordt als gevolg van de aanwezigheid van nog onbekende microbiële factoren. Deze opbrengstverlaging varieerde van 30% in 1982 tot slechts 3% in 1983 in de 3-jarige rotaties. Pootgoedbacterisatie had in deze proefvelden een significante toename van de eindopbrengst (vier tot vijf maanden na pootdatum) van consumptieaardappelen tot gevolg, die varieerde van 9 tot 20%, echter allen in 1981. In 1982 en 1983 werd het effect van bacterisatie ook in de loop van de groeiperiode onderzocht. Aanvankelijk significante toenames van zowel spruit-als knolgewicht waren aan het einde van het groeiseizoen niet meer aantoonbaar. Pootgoedbacteristie bleek geen effect te hebben op aardappel in ruimte rotaties. Aanvankelijk werden de basale wortelgedeelten gekoloniseerd door antibioticum-resistente mutanten met 53×104 kolonievormende eenheden (kve) per gram wortel(vers); dit aantal liep (drie maanden na pootdatum) echter significant terug tot 20×104 kve per gram. Het effect van bacterisatie op de eindopbrengst werd bepaald door de ontwikkeling van de schadelijke microbiële activiteit en de ontwikkeling van de geïntroduceerde antagonisten tijdens het groeiseizoen. Pootgoedbacterisatie in nauwe rotaties biedt meer mogelijkheden voor de teelt van pootaardappelen dan die van consumptieaardappelen, die geruime tijd later geoogst worden. 相似文献
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H.-L. WEIDEMANN 《EPPO Bulletin》1987,17(1):45-50
Potato spindle tuber viroid (PSTV) in potato plants was investigated by ‘return’ gel electrophoresis. The experiments were carried out under quarantine conditions in the greenhouse with primarily and secondarily infected plants. The PSTV content in different plant parts was estimated by the intensity of the viroid band in polyacrylamide gel. The results showed a decrease of viroid content from the upper to the lower parts of the plant. In both primarily and secondarily infected plants, PSTV was reliably detected in the top leaves, but less so in the lower leaves. In four out of ten secondarily infected plants, PSTV was found in the roots. In dormant tubers, the bands were more intense with samples obtained from the rose end and the heel than from those obtained from the medullary tissue. With one exception, all 64 tubers from 26 primarily infected plants were infected with PSTV. 相似文献