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济宁市的棉花苗期病害主要是棉苗立枯病 (Rhizoctonia solani), 其次是棉苗炭疽病 (Colletotri-chum gossypii)、红腐病 (Fusarium moniliforme)等.其发生程度除受种子带菌、土壤带菌影响外,主要与棉苗定植后的气候条件相关.据统计资料表明,济宁市 1990～ 2003年 14 a中,发生程度中等偏上年份有 8 a(1992、 1993、 1996、 1997、 1999、 2001、 2002、 2003). 2003年棉花苗期病害在全市大发生,发生面积达 6.57万 hm2,占棉花种植面积的 75.8%,且发病早,持续时间长,死苗率高.据鱼台、金乡县调查, 4月下旬 60%苗床发病,严重苗床病株率达 30%, 5月上、中旬大田普查,病田率达 100%,病株率平均达 55.5%,最高 86.5%,死苗率 5%～ 10.5%,高的达 20.3%,田间缺苗断垄严重.全市发生程度与发生面积也超过以往任何一年. 相似文献
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今年我区鄂晚5号为主的稻瘟病严重发生,造成严重减产,其中以穗瘟减产最重。现将其发生特点及原因浅析如下: 1 发病特点 1.1 苗瘟、叶瘟、穗瘟连发 今年我区晚稻的苗瘟病苗率一般在20％～30％,重病田超过50％;叶瘟发生早,新老病叶共存时间长,而且随着晚稻分蘖的不断增加,新病叶不断产生,尤其是急性病斑的数量大(单叶病叶最多达23个),持续时间长,导致发病面积不断扩大,病情不断加重,孕穗后期重病田上三叶急性病斑的病叶率达34.7％,抽穗期上三叶叶枕瘟率达32.6％～44.7％;今年穗瘟虽然早在9月下旬就发病,但病害大量表现和加重期在10月上中 相似文献
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水肥因素对膜下滴灌棉花产量和棉株群体冠层结构的影响研究 总被引：19，自引：0，他引：19
以新陆早7号为试材，进行了不同水肥条件下膜下滴灌棉株群体冠层结构测定和产量结果分析。试验表明，合理水肥条件下的棉株群体叶面积指数(LAI)、叶倾角(MLA)和散射光透过率(TD)，在盛花盛铃期分别为3.55～3.95、40°～48°和18.5%～28.1%。在一定水肥范围内，滴灌棉花产量随灌水量和施肥量的增加而增加，但超过一定阈值产量有下降趋势。适宜水肥条件下产量最高。 相似文献
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黄瓜花叶病毒CA株系在花生上流行的研究 总被引：5，自引：0，他引：5
据1985~1990年在密云县试验观察,黄瓜花叶病毒(CMV)在花生上流行受病毒种传率、苗期蚜虫发生数量及苗期温度和雨量的影响。花生苗期和花针初期为易感病时期,随后抗性有所增强,但不明显。苗期和花针期发病植株,CMV种传率最高,之后带毒率有所下降。CMV种传率高低与病害流行关系,在同一年份呈极显著正相关关系,而在年度间未达显著水平。花生田间蚜虫发生盛期与病害发生高峰期是吻合的,蚜虫发生数量与病害流行关系显著。根据花生种传率和苗期蚜虫发生数量两因素6年次资料配合的病害流行预测式,其回报可靠度的置信范围在93%左右。 相似文献
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根据六年来的资料分析,在东北各地松苗立枯病发生的开始时期,一般多在5月中旬,北部则稍迟;流行盛期在5月下旬至6月上、中旬间,为期将近一个月;发病休止期约在7月初旬至8月中旬,差异比发病开始时期大。病害发生延续期约45—82天,平均发病期为61.4天。红松幼苗发病与流行盛期较晚,与樟子松和落叶松有所不同。三种立枯病菌病苗的出现时期受土壤温度的影响。丝核菌(Rhizoctonia)病苗发生最多在土温18—22℃,腐霉菌(Pythium)在17—22℃,镰刀菌(Fusarium)在23—28℃,所以一般早期发生的病苗主要为丝核菌侵染所致,其次为腐霉菌,在后期则多数为镰刀菌,但如早期土温较高时,亦有较多的镰刀菌病苗。总的发病土温范围是11—30℃,适温为18—25℃,红松幼苗的发病土壤适温还要高些。松苗立枯病在东北地区的流行主要受土壤含水量和降雨量的影响。松苗在生长感染期间,如遇雨量大和次数多或土壤含水量高时,则有利于发病,几天后在流行曲线上即可出现发病率的高峯。土壤温度不是病害流行的主要限制因素,因为在幼苗生长期间,土温范围都适宜于立枯病的发生。在同一地区的发病期间,苗床土壤 pH 值的变动并不显著,故在同一地区病害流行与 pH 值关系亦不大。当年病害发生总百分率的高低,除受气候因素的影响外,还受病害发生延续期长短的影响。如发病延续期久,则总的发病率较高。 相似文献
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三大棉种对棉花主要病害抗性研究 总被引：9，自引：0，他引：9
1633个陆地棉、海岛棉、中棉三大棉种的品种资源和42个生产上推广应用的陆地棉品种,在田间病圃和温室接菌,进行对枯萎病、黄萎病、苗病、铃病的抗病性鉴定。结果表明,中棉对枯萎病、苗病,铃病均有较高的抗病能力,但对黄萎病抗性较差;海岛棉对黄萎病有很高的抗病能力,但对枯萎病、苗病、铃病抗性均较差;陆地棉对棉花4种主要病害的抗病性能高于海岛棉,但低于中棉。经生物统计分析,仅发现陆地棉抗枯萎病与抗苗病之间存在显著的正相关关系。推荐中棉12、陕1155、86-2、86-3、冀合3016五个兼抗枯、黄萎病,并对苗病、铃病也有一定耐病性的品种,供各地多抗育种选用。 相似文献
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棉株施用缩节胺后能减少棉铃虫(Heliothis armigera Habner)在棉株上的落卵量48.8%—88%,田间虫量减少39.5%—77.3%,取食嫩叶、花蕾后的2龄幼虫体重下降、发育历期延长,死亡率增加,化蛹率和羽化率都有下降,总的生存率降低了57.62%。测定表明施用缩节胺后,棉株各部组织内棉酚有增加趋势,以蕾内增加较多,为49%—92.1%,铃壳次之,为13.8%—65.5%,叶内较少,为3.6%—39.7%。而单宁量除大铃壳内有增外,大多下降。施用次数与剂量的增加,与棉酚量的提高有共同趋势。花蕾期施用,棉酚量的增加高于花铃期。 相似文献
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ABSTRACT Recent reports have shown induction of resistance to Rhizoctonia root rot using nonpathogenic strains of binucleate Rhizoctonia spp. (np-BNR). This study evaluates the biocontrol ability of several np-BNR isolates against root and foliar diseases of cotton in greenhouse trials, provides evidence for induced systemic resistance (ISR) as a mechanism in this biocontrol, and compares the disease control provided by np-BNR with that provided by the chemical inducer benzothiadiazole (BTH). Pretreatment of cotton seedlings with np-BNR isolates provided good protection against pre- and post-emergence damping-off caused by a virulent strain of Rhizoctonia solani (AG-4). Seedling stand of protected cotton was significantly higher (P < 0.05) than that of nonprotected seedlings. Several np-BNR isolates significantly reduced disease severity. The combination of BTH and np-BNR provided significant protection against seedling rot and leaf spot in cotton; however, the degree of disease reduction was comparable to that obtained with np-BNR treatment alone. Significant reduction in leaf spot symptoms caused by Alternaria macrospora occurred on cotyledons pretreated with np-BNR or sprayed with BTH, and the np- BNR-treated seedlings had significantly less leaf spot than BTH-treated seedlings. The results demonstrate that np-BNR isolates can protect cotton from infections caused by both root and leaf pathogens and that disease control was superior to that observed with a chemical inducer. 相似文献
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Soichiro Morita Mikiko Azuma Toshiko Aoba Hiroya Satou Kazuhiko Narisawa Teruyoshi Hashiba 《Journal of General Plant Pathology》2003,69(1):71-75
The root endophytic fungus Heteroconium chaetospira isolate OGR-3 was tested for its ability to induce systemic resistance in Chinese cabbage against bacterial leaf spot caused
by Pseudomonas syringae pv. maculicola and Alternaria leaf spot caused by Alternaria brassicae of the foliar diseases. Chinese cabbage seedlings planted in soil infested with an isolate of H. chaetospira were incubated in a growth chamber for 32 days. The first to fourth true leaves of the seedlings were challenge-inoculated
with P. syringae pv. maculicola or A. brassicae. Chinese cabbage planted in soil infested with H. chaetospira showed significant decreases in the number of lesions of bacterial leaf spot or Alternaria leaf spot when compared to the
control plants not treated with H. chaetospira. The results indicated that colonization of roots by H. chaetospira could induce systemic resistance in Chinese cabbage and reduce the incidence of bacterial leaf spot and Alternaria leaf spot.
Received: April 24, 2002 / Accepted: August 9, 2002 相似文献
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通过棉花抗枯萎病品种苗期鉴定,可以反应出不同品种和品系的抗病性。温室系统观察结果,棉苗在1—2片真叶时即有症状出现,以感病品种发生较早。一般在4—5片真叶期,枯萎病发生甚烈。不同品种(系)反应的症状类型有所差异,但大多数属于三个类型:“网纹型”、“青枯型”、“黄叶型”。观察到“网纹”和“黄叶”属慢性类型;“青枯”属急性类型。从242个品种(系)材抖中,鉴定出苗期抗病的品种(系)23个,均属抗型(R)。发病指数0—10%有11系,11—20%有8系,21—30%有4系;其中有免疫类型1系(61—84),发病指数为0。苗期属抗病类型,移植到病圃后,成株期仍反应出较多抗病类型,其中苗期属高抗和免疫株系,成株期的抗性反应亦基本一致。 相似文献
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甘肃省红豆草病原真菌鉴定及病害发生动态调查 总被引：4，自引：1，他引：3
为明确甘肃省红豆草的病害种类、发生动态和危害状况,采用病原物分离与培养、形态学及分子生物学鉴定和致病性测定确定红豆草病害种类,于2012—2013年在通渭、渭源、榆中和碌曲4县调查各病害的发病率以确定发生动态,观察病害田间发生特点并结合调查数据评价其重要性。结果表明,4县共发生真菌性病害12种,分别为大茎点霉叶斑病(病原为大茎点霉属真菌Macrophoma sp.)、壳针孢叶斑病(病原为歪头菜壳针孢Septoria orobina)、炭疽病(病原为白蜡树刺盘孢Colletotrichum spaethianum)、黑秆病(病原为红豆草壳二孢Ascochyta onobrychis、菠菜刺盘孢C.spinaciae和链格孢Alternaria alternata混合侵染)、壳二孢叶斑病、茎点霉叶斑病、尾孢叶斑病、柱格孢白斑病、匍柄霉叶斑病、链格孢黑斑病、锈病和白粉病,其中大茎点霉属真菌、白蜡树刺盘孢和菠菜刺盘孢在红豆草上首次发现;尾孢叶斑病和壳针孢叶斑病为甘肃新记录病害;大茎点霉叶斑病为世界新病害,仅于碌曲县发现。白粉病、锈病、链格孢黑斑病发生于红豆草生长后期,其它病害则始于6月;6—9月危害加重的为黑秆病和柱格孢白斑病,发病率最高达89.7%和96.0%;危害渐轻的为茎点霉叶斑病、壳二孢叶斑病和壳针孢叶斑病,发病率最高达88.7%、57.4%和45.1%。黑秆病和茎点霉叶斑病在甘肃省目前危害最重。 相似文献
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Possible Root Infection of Cercospora beticola in Sugar Beet 总被引：1，自引：0，他引：1
Jessica Vereijssen Hans J.H.M. Schneider Aad A.J. Termorshuizen 《European journal of plant pathology / European Foundation for Plant Pathology》2004,110(1):103-106
A potential primary infection site of the foliar pathogen Cercospora beticola in sugar beet is described. Sugar beet seedlings of the susceptible cv. Auris were grown in a standard soil for 14 days. A monoconidial culture of a C. beticola isolate was grown to produce conidia. In experiment 1, roots were immersed in a conidial suspension of isolate code IRS 00-4, or in tap water (control), for 2 days. After incubation seedlings were potted in a peat – fine river sand mixture and placed at low relative humidity (RH) (<80%) or high RH (100%). Twelve days after infection, seedlings at high RH showed more disease incidence (90%) than seedlings grown at low RH (disease incidence = 25%), whereas no disease symptoms developed in the control seedlings. Cercospora leaf spots (CLSs) developed on the cotyledons, leaves, petioles and stems of the seedlings. In experiment 2, roots were immersed in a conidial suspension of isolate code IRS 00-2 for 5 h. Thirty-four days after infection at high RH, 100% disease incidence was observed in the treated seedlings and one CLS in the control treatment. First indications of leaf spot development were observed as reddish purple discolouration of individual parenchymatic cells. Because splash dispersal and symptoms due to infested soil were excluded, we showed that it is possible to obtain CLS symptoms in sugar beet seedlings when their roots were immersed in conidial suspensions of C. beticola, thus demonstrating that roots can be a primary infection site. 相似文献
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Masashi Fujinaga Hideki Ogiso Hidetada Wakabayashi Toshiyuki Morikawa Tomohide Natsuaki 《Journal of General Plant Pathology》2009,75(2):157-159
A viral disease was found in Nagano Prefecture, Japan, on statice (Limonium sinuatum) with chlorotic leaf spot, necrotic stunt, and dwarfing. Spherical virus particles 30 nm in diameter were isolated from infected
plants and statice seedlings and caused identical symptoms 4 weeks after mechanical inoculation. Nucleotide and deduced amino
acid sequences of the coat protein showed 98% and 98.7% identities with those of Grapevine Algerian latent virus (GALV) nipplefruit strain. This is the first report in Japan of a viral disease on statice caused by GALV.
The nucleotide sequence data reported here are available in the DDBJ/EMBL/GenBank databases under accession AB461854. 相似文献
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In May 1998 and 1999, two types of leaf spot (black type and brown type) caused by Phoma spp. were found on Farfugium japonicum in Tokyo and in Gunma Prefecture, Japan. The fungus isolated from black-type lesions caused only black-type lesions, and the fungus from brown-type lesions caused only brown-type lesions. We propose to name these diseases black leaf spot of F. japonicum (kokuhan-byo in Japanese) for the disease with black lesions and circular leaf spot of F. japonicum (rinmon-byo in Japanese) for the disease with brown lesions. This is the first report on leaf diseases of F. japonicum caused by Phoma spp. 相似文献
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Eliana Wassermann Marcela Susana Montecchia Olga Susana Correa Vega Damián Ana María Romero 《European journal of plant pathology / European Foundation for Plant Pathology》2017,148(1):35-44
Tomato leaves showing severe leaf spot symptoms have been observed and sampled in the central west and southwest Taiwan during 2015 and 2016. The symptoms were similar to those of bacterial leaf spot/late blight diseases, but only Stemphylium-like fungi were consistently isolated from the diseased tomato. Upon spray inoculation of tomato, Stemphylium-like isolates caused leaf spot symptoms identical to those of naturally infected plants, and the pathogenic isolates were successfully re-isolated from inoculated leaves. The tomato-pathogenic isolates were identified as S. lycopersici based on morphological characterization and molecular identification. S. lycopersici has been previously reported to cause gray leaf spot of tomato in the temperate regions, but the majority of S. lycopersici-caused lesions were black/dark brown rather than gray in our surveillance. Accordingly, it is suggested that S. lycopersici-caused disease of tomato is named Stemphylium leaf spot of tomato more appropriately than tomato gray leaf spot. Moreover, S. lycopersici-caused leaf spot disease on tomato has been distributed in major tomato production regions in Taiwan. The information provided by our study will be important for future breeding of tomato cultivars, especially for tomato producers in Taiwan. 相似文献