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对2015－2020年参加西北内陆棉区区域试验的192个棉花品种（系）枯萎病、黄萎病的抗性分析，为棉花抗病育种及品种推广提供依据。结果表明，参试棉花品种（系）未出现对枯萎病和黄萎病免疫的品种；参试棉花品种（系）对枯萎病的抗性水平较高，除2018年高抗和抗病品种（系）占比为 88.2%外，其他年份均在92%以上；参试的品种（系）的黄萎病抗性水平除2017年较高外，其余各年均较低，以耐病为主，6年耐病品种（系）平均占比为56.2%；参试品种的总体抗枯萎病指数（rF）远大于总体抗黄萎病指数（rV）和总体兼抗指数（rFV）,各年份均表现为rF＞rV＞rFV，且三者均呈振荡上升趋势；早中熟常规棉的抗枯萎病、黄萎病性及兼抗性表现均优于早熟常规棉。可见，黄萎病抗性的提高是西北内陆棉区选育兼抗棉花品种的关键。 相似文献
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为明确河南省棉花区域试验新品种（系）的抗病水平,分析比较了2015―2019年参试的244个品种（系）对枯萎病、黄萎病的抗性。结果表明：参试品种（系）的抗枯萎病性水平较高,高抗和抗病品种（系）比例均在50%以上;对黄萎病的抗性有待提高,仍以耐黄萎病品种为主;兼抗品种所占的比例较低,枯萎病总体抗性指数（rF）远大于黄萎病总体抗性指数（rV）和总体兼抗指数（rFV）,各年份均表现为rF＞rV＞rFV;常规棉品种（系）对枯萎病的抗性优于杂交棉,但2类品种（系）的黄萎病抗性差异不大;夏棉对枯萎病的抗性优于春棉,而春棉的rV优于夏棉。 相似文献
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2015―2019年国家黄河流域棉花品种区域试验参试品种（系）枯黄萎病抗性评述 总被引：1，自引：0，他引：1
为明确当前黄河流域棉区新品种（系）的抗病水平，比较分析了2015－2019年黄河流域棉区213个参试品种（系）对枯萎病、黄萎病的抗性。结果表明，参试品种（系）的抗枯萎病性水平较高，高抗和抗病品种（系）比例均在60%以上,总体抗枯萎病指数（rF）为48.2～75.0；参试品种（系）对黄萎病抗性为中等水平,抗病品种（系）所占比例为3.6%～24.6%，呈逐年升高趋势,总体抗黄萎病指数（rV）为22.3～31.1；参试品种（系）的总体兼抗指数（rFV）为11.4～17.4;各年度均表现为rF＞rV＞rFV；常规棉品种（系）抗枯萎病性高于杂交棉品种（系），但2类品种（系）的抗黄萎病性差异不大。 相似文献
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1998-2011年黄河流域棉区棉花品种区域试验参试品种(系)抗病性评述 总被引：2，自引：0，他引：2
比较分析1998-2011年黄河流域棉区棉花品种区域试验560个参试品种(系)的抗病性表明:品种的抗枯萎病性水平较高,而抗黄萎病性和兼抗性水平较低;常规品种与杂交种抗病性差别不大,中熟、中早熟品种抗性总体好于早熟品种。参试品种的总体抗黄萎病指数和兼抗指数分别较1991-1997年参试品种高9.4和4.6百分点,总体抗枯萎病指数与之相当。参试品种中抗病品种比例的变化趋势为,抗枯萎病品种比例在达到较高水平后有回落趋势,抗黄萎病和兼抗品种比例起伏不稳,仍在较低水平。 相似文献
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对2016―2020年参加长江流域棉区区域试验的159个棉花新品种（系）对棉铃虫抗性的动态进行分析，为棉花抗虫育种及品种推广提供理论依据。参试品种（系）类型包含中熟常规棉、中熟杂交棉和早熟常规棉。结果表明，参试棉花品种（系）对棉铃虫的抗性水平较高，除2020年有4.35%的低抗品种（系）外，其他均为中抗或高抗，无不抗棉铃虫的品种（系）。多数年份以抗虫品种（系）为主。中熟杂交棉抗虫性多优于中熟常规棉，棉花苗期平均抗性多高于蕾铃期。5年参试品种（系）对棉铃虫的平均抗性值总体呈现波动上升趋势。 相似文献
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为明确当前黄河流域棉区新品种（系）的抗病水平，比较分析了2015－2019年黄河流域棉区213个参试品种（系）对枯萎病、黄萎病的抗性。结果表明，参试品种（系）的抗枯萎病性水平较高，高抗和抗病品种（系）比例均在60%以上,总体抗枯萎病指数（rF）为48.2～75.0；参试品种（系）对黄萎病抗性为中等水平,抗病品种（系）所占比例为3.6%～24.6%，呈逐年升高趋势,总体抗黄萎病指数（rV）为22.3～31.1；参试品种（系）的总体兼抗指数（rFV）为11.4～17.4;各年度均表现为rF＞rV＞rFV；常规棉品种（系）抗枯萎病性高于杂交棉品种（系），但2类品种（系）的抗黄萎病性差异不大。 相似文献
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Potato early dying, incited byVerticillium dahliae, was found to be the major factor in reducing the yield potential of potato grown under our conditions. Immediate attempts at control involved the screening of commercial cultivars and lines bred in both the USA and Europe, and various soil fumigation treatments. This work led to the selection of cultivars with reasonably high tolerance and the elucidation of the role that the nematodePratylenchus thornei plays in the disease syndrome. Elimination of the nematode by sprinkler applied metham-sodium in conjunction with some of the above cultivars now produces yields of 40–60 metric T/ha, depending on the cultivar and season. More recently, our research has been directed towards the use of serological methods to detect the pathogen in locally produced seed tubers and the utilization of an extracellular toxin produced by the pathogen in determining resistance to the fungus. With regard to the former, we have been able to produce an antibody that reacts solely toV. dahliae and can be used in several serological tests to determine the presence of the pathogen. Our work has also shown that utilization of the toxin offers a highly reliable technique in determining at least certain forms of resistance. 相似文献
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Summary Field surveys of 2600 plants during growth of the autumn crop and of 1700 plants of the spring crop showed that 6.5% and 4.0%
respectively were attacked byFusarium wilt; on average, 40% of the tubers from wilted plants were infected. Similar results were obtained in an artificially infested
field. Examination of 6105 planting positions in the field during growth of the autumn crop showed that 28.7% of seed tuber
rots were caused byFusarium oxysporum f.sp.tuberosi, while in spring crop this percentage was much lower. The yield in an artificially inoculated field was reduced from 10 to
53% compared to controls, depending on the cultivar.
Zusammenfassung In Felduntersuchungen wurden mitFusarium infizierte Pflanzen und Knollen nach dem Zufallsprinzip erfasst, und zwar an verschiedenen Orten in mehreren Feldern an jeweils mindestens 100 Pflanzstellen. Von den 2600 Pflanzen aus dem Herbstanbau und 1700 aus dem Frühjahrsanbau, waren 6,5% bzw. 4,0% von derFusarium-welke befallen (Tab. 5). Von 30 Pflanzen mit Welkesymptomen starben 6 vor dem Knollenansatz ab, die übrigen 24 hatten 119 Knollen, von denen 48 mitFusarium infiziert waren. Nach 3 Monaten waren von denselben Knollen noch 34% mitFusarium befallen (Tab. 6). Die Untersuchung des Knollenauflaufs an 6105 Pflanzstellen ergab im Herbst eine Auflaufrate von nur 81,7%. Von den restlichen 18,3% der nicht gekeimten Knollen wurden 29,7% nicht wiedergefunden, 23,3% hatten Nassf?ule und in nur 2,3% fauler Knollen wurdenRhizoctonia undSklerotium gefunden. 44,7% der F?ulen waren vonFusarium-Trockenf?ulen verursacht worden. Isolierungen von 106 dieser Knollen ergaben in 68 F?llen Befall mitFusarium oxysporum, das entspricht 5,2% von der gesamten Probe (Tab. 4). Die Ergebnisse aus dem Frühjahrsanbau waren ?hnlich, die Verluste jedoch viel geringer. In der experimentellen Arbeit wurden Knollen verschiedener Sorten aus Pflanzkartoffelgebieten verwendet sowie einF. oxysporum f.sp.tuberosi-Isolat von einer griechischen Kartoffelpflanze mit Welkesymptomen. Der Krankheitsindex erstreckte sich von 0,20 bis 1,07, so dass der mittlere Ertrag nicht reduziert war. Die neuen Knollen zeigten im Lager eine Gesamtinfektion mitFusarium von 5–42% (Tab. 7), was gut mit den Felduntersuchungen übereinstimmt. Die lineare Regression des Ertrages in Bezug auf den Krankheitsindex ergab eine Ertragsreduktion von 10 bis 53%.
Résumé Au cours d'observations au champ réalisées dans différents endroits,Fusarium contamine les plantes et les tubercules dans pas moins de 100 cas par endroit. Un flétrissement provoqué parFusarium a été observé sur 2600 plantes en culture d'automne et sur 1700 plantes en culture de printemps, avec respectivement un taux de 6,5% et 4,0% (tabl. 5). Sur 30 plantes flétries, 6 sont détruites avant formation des tubercules. Les 24 plantes restantes produisent 119 tubercules dont 48 sont infectés parFusarium. Les mêmes tubercules, trois mois après, présentent 34% deFusarium (tabl. 6). L'examen de tubercules formés pendant l'automne dans 6105 endroits montre que 81,7% de tubercules ont germé et sur le reste non germé, 29,7% ont disparu, 23,3% sont pourris alors queRhizoctonia etSclerotium sont responsables de seulement 2,3% de tubercules pourris. Les 44,7% des tubercules restants sont atteints de pourritures sèches provoquées parFusarium. Les isolements réalisés à partir de 106 de ces tubercules metent en évidence la présence deF. oxysporum dans 68 cas ce qui représente 5,2% de l'ensemble des échantillons (tabl. 4). Les résultats concernant les cultures de printemps sont similaires mais les pertes sont plus faibles. Dans un travail expérimental sont utilisés des tubercules provenant de régions de production de différentes variétés de semences et un isolat deF. oxysporum f.sp.tuberosi provenant de plantes de pomme de terre flétries de Grèce. L'indice de maladie étant entre 0,20 et 1,07 ce qui ne réduit pas le rendement moyen. Les nouveaux tubercules stockés ont présenté un degré d'infection totale parFusarium de 5 à 42% (tabl. 7) ce qui est en complet accord avec les observations au champ. Une régression linéaire entre rendement et indice de la maladie montre des réductions de rendement de 10 à 53%.相似文献
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Watermelon yield loss due to Fusarium wilt is increasing in the U.S., due in part to the emergence of the virulent race 2 of Fusarium oxysporum f. sp. niveum, and to the shift in production to triploid cultivars, which generally have less host resistance than previously grown diploid cultivars. One potential management strategy is the use of soil-applied fungicides to reduce Fusarium wilt. The U.S. national program, interregional project 4 (IR-4) supported multistate trials of soil-applied chemicals to manage Fusarium wilt of watermelon. Greenhouse trials were conducted in Maryland, Indiana and Georgia to test the efficacy of 14 chemicals on Fusarium wilt. Based on the performance of these chemicals in the greenhouse, six in Maryland and Delaware and eight in Indiana were selected for subsequent field evaluations. These chemicals were applied once, as a drench at planting, in field trials in Maryland, Indiana, and Delaware in 2008. The fungicides prothioconazole, acibenzolar-S-methyl, and thiophanate-methyl resulted in the greatest reduction in Fusarium wilt, and caused no phytotoxicity. In Maryland and Indiana in 2009, these chemicals were applied through the drip irrigation line alone and in combination, at 0, 2 and 4 weeks after planting. The experiment was repeated in 2010 in Maryland. Prothioconazole alone and in combination with acibenzolar-S-methyl or/and thiophanate-methyl resulted in the greatest decrease in the area under the disease progress curve (AUDPC) of Fusarium wilt of watermelon in Maryland in 2009. The same trend was observed in 2010 in Maryland where three of the prothioconazole treatments ranked the lowest of all treatments and prothioconazole in combination with thiophanate-methyl had significantly lower Fusarium wilt AUDPC compared to the non-treated control. All chemical applications except for acibenzolar-S-methyl in combination with prothioconazole reduced Fusarium wilt AUDPC in Indiana in 2009. Prothioconazole alone and prothioconazole in combination with thiophanate-methyl ranked lowest in Fusarium wilt AUDPC, although not significantly lower than most other treatments. These studies are the first to demonstrate that the soil-applied fungicides prothioconazole and thiophanate-methyl may provide an additional field management option for Fusarium wilt of watermelon. 相似文献
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Carlos Martin 《American Journal of Potato Research》1985,62(4):195-199
Studies in the 1950’s indicated thatVerticillium alboatrum was present in potato fields in the irrigated coastal valleys of central Peru. No further studies were carried out in Peru until those in the late 1970’s initiated at The International Potato Center. So far, Verticillium wilt of potatoes has been observed in several valleys of the coast as well as in highland valleys at elevations up to 3400 m. Although the frequency of isolation ofVerticillium sp. has been much greater in the highlands, the disease is of less consequence there because of low temperatures during the growing season. The most common symptom observed in the field is early senescence, including yellowing and stunting of the foliage. Typical “wilt” symptoms are rarely found. Both in the coastal valleys and in the highlands, onlyVerticillium dahliae has been identified. Although no studies on losses and the economic importance of Verticillium wilt of potatoes have been done, it is clear that the two most important crops used in rotation in coastal valleys of central Peru, potato and cotton, are severely affected. 相似文献
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