论文标题:仙客来叶斑病病原学及防治技术研究
Studies on the Pathology & Control Measures of Cyclaman Leaf Spot Disease
论文作者 王婧
论文导师 徐秉良,论文学位 硕士,论文专业 植物病理学
论文单位 甘肃农业大学,点击次数 126,论文页数 66页File Size3039k
2004-06-01论文网 http://www.lw23.com/lunwen_765058942/ 仙客来叶斑病;链格孢菌;生物学特性;发病规律;综合防治
Cyclaman Leaf spot disease;Pathogen Identification;Occurrence;Regularity; Control Measures
本试验首次较系统地对仙客来叶斑病的病原学、生物学特性、发生规律及防治技术进行了研究。仙客来叶斑病是近几年发生并报道的一种新的仙客来叶部病害，发病率一般在20-30%，严重时可达50%，给生产造成了一定的损失。本试验对兰州市主要仙客来品种进行了叶斑病病情统计和病样分离，获得了致病菌株，根据病原菌致病性、生物学特性、培养性状及形态学研究结果，并参考相关的文献资料，将其确认为链格孢菌（Alternaria alternata (Fr.) Keissler）。病原生物学研究表明：菌丝生长和分生孢子萌发在10℃~45℃的温度范围内均可进行，其中30℃为菌丝生长和孢子产生的最适温度， 25~30℃是菌丝生长及孢子产生适宜的温度范围；相对湿度大、保持时间长有利于孢子萌发；光照有抑制产孢但可促进孢子萌发的作用，紫外灯对孢子有很强的杀伤作用；病菌菌丝及孢子萌发在pH4.0-9.0之间均能生长及萌发，但微酸性环境有利于孢子萌发，其最适pH为6.0—7.0； 菌丝对碳素营养利用以葡萄糖、麦芽糖、蔗糖效果最好，乳糖和淀粉的利用较差；孢子形成量以蔗糖为最好；在氮素营养中病原菌对硝酸钾和甘氨酸利用最好，氯化铵利用最差。对仙客来叶斑病发生规律的研究表明：病原菌以菌丝或分生孢子的形式在病残体上越冬，从而成为该病的主要侵染源，此外，种子表面带菌是另一个传播途径。湿度是影响病害发生流行的主导因素，高湿有利于病害的发生；氮肥用量过多，可加重病害的发生；适当增施钾肥可增强植株的抗病性，减轻病害的发生；轮作也可减轻病害的发生。对仙客来叶斑病防治技术的研究表明，拉蒂尼亚、哈里奥、火焰等仙客来品种对叶斑病抗性较强；合理轮作可有效减轻发病； 80%大生wp500×、72%速克灵wp800×和多菌灵wp600×化学药剂可有效防治仙客来叶斑病，并且经济安全、无副作用；此外，以0.1%高锰酸钾浸种30min，或52℃温汤浸种10min进行种子处理，可以显著降低种子带菌量。通过对仙客来叶斑病较系统的研究，本论文总结出了选用抗病品种，种子消毒，消除田间病残体，加强栽培管理、合理轮作、合理施肥、及时进行药剂防治等综合防治措施。
It is the first time that the pathogens, biological characteristics, occurrence regularity and control measures of cyclamen leaf spot disease are studied systematiclally through this trialCyclaman leaf spot is the new leaf disease which was epidemic and reported in recent years. Its incidence rate was 20% to 30% generally, but can severely reach to 50%.The pathogenetic strains of cyclaman leaf spot was obtained by isolation and investigation. It was identified as Alternaria. alternata(Fr) keissler, according to its pathogenicity, biological characteristics, cultivation and shape.The biological test showed that the mycelia could grow and conidial could germinate at 10-45℃,and the optimal condition for the mycelia growth and spores formation is at 30℃,the suitable condition is at 25-30℃.Light could repress the formation of spores,but could accelerate the germination of spores The mycelia could grow and conidial could germinate when the value of pH is 4.0-9.0, and the optimal pH is 6.0-7.0.The mycelia can utilize the substances of carbon sources such as grapesugar,maltose.sucrose very well. More spores could be produced well on sucrose .The Nithogen sources such as potassiym nitrate and. Glycine could be highly benefited to their growth.The result of study on occurrence regularity showed: Pathogen overwintered with my celium and conidia on marigold refuse, which were the primary infection resources, secordly was from infected seeds. The occurences of the disease was obosely correlated with humidity, amount and kind of fertilizers and crop rotation. High humidity or more N was favorably for the disease epidemic, but right P and rotation could increase the variety resistance to the disease.According to studies on the control measures showed: seclecting and cultivating the disease-resistant varities of Cyclaman such as Latinia and Halios etc, seeds disinfect and fungicides sereening were experienced. The result indicated that Cyclaman leaf spot disease was effectively controlled with spraying “80% Dasheng wp500×”, “72%Sukelin wp800×”, “Duojunlin wp 400×”, meanwhile, infecting with 0.1% KMnO4 for 30 min or soaking with 52oC water for 10 min could markedly reduce the amount of the fungi.Total to say, the integrated controlling measures of cyclamary leaf spot have been put forward by studying systematically the disease.These measures include selecting the disease and cultivating resistante varities of cyclaman, soaking the seeds, cleaning away marigold refuse in the field, strengthening croprotation and cultivation managements , applying fertilizers and properly spraying fungicides appropriately.
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