http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/194 Thu, 12 Mar 2026 08:17:10 GMT 2026-03-12T08:17:10Z http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/74388 標題: 黃龍病菌於柑橘寄主體內之移動與影響亞洲柑橘木蝨 (半翅目：扁木蝨科) 獲菌因子之探討; Studies on the movement of Candidatus Liberibacter asiaticus in citrus hosts and the factors which influence pathogen acquisition for psyllids, Diaphorina citri Kuwayama (Hemiptera:Liviidae) 作者: Tsung-Han Lee; 李宗翰 摘要: 由韌皮部侷限細菌所引起的柑橘黃龍病 (Citrus huanglongbing, HLB) 是影響柑橘生產的重要病害，危害世界各大柑橘產區，而年產量高達50萬公噸以上的臺灣亦受嚴重波及。根據2017年田間調查的結果顯示臺灣約有31.9%之罹病率，且各品種皆會染病，造成果實的品質及產量大打折扣。目前已知病害的感染途徑主要藉由嫁接及媒介昆蟲進行傳播，而自1973年起積極推廣健康柑橘種苗概念之下，柑橘園中的亞洲柑橘木蝨 (Diaphorina citri Kuwayama) 似乎成為病害擴散的一大隱憂，對於媒介木蝨傳病生態學的相關研究，則可提供黃龍病防治策略的重要參考。本研究藉由分析不同生長期的柑橘品種其新梢帶菌的情形，以推估黃龍病菌自病徵明顯的老熟組織移動至幼嫩葉部所需的時間，結果發現柳橙在新梢生長一週後即可測得黃龍病菌，往後隨週數的進展菌量呈微幅增長；椪柑及桶柑則在兩週過後病原菌便開始快速增殖，到第四週時菌量達所有品種中的最高，而黃龍病菌在白金柚中的移動最為緩慢，至三、四週後才可在新梢中檢測到少量存在。病原菌移動至新梢後，因木蝨對嫩葉處具有強烈的偏好，進而提供受吸引前來的木蝨獲菌的機會，文中亦針對可能影響木蝨獲菌的因子進行探討，在調查不同齡期若蟲的獲菌情形中，發現自二齡起木蝨即具獲菌的能力，又以四齡及五齡若蟲的帶菌量最高，五齡若蟲的帶菌量約與初獲菌的二齡若蟲相差近130倍；取食病株的時間長短亦會造成獲菌差異，在14天時初有30%的帶菌蟲比例，到28天時則升高至80%，說明獲菌情形可能隨時間的延長而提升；而不同的柑橘品種及其罹病情形也是影響木蝨獲菌的可能因子，以罹病三個月後的柳橙最早有木蝨獲菌的記錄，椪柑及文旦亦在四、五個月時相繼出現木蝨獲菌的情形，而任一品種皆發生在完整病徵出現以前。進入木蝨體內的黃龍病菌隨開放系統進行循環，以持續取食月橘屬 (Murraya spp.) 植株的試驗中觀察病原菌於媒介昆蟲體內的增殖效率，而長至四週後仍能檢測到帶菌情形，證實病原於蟲體內的保存效力，一旦經有效獲菌後，則可能終生成為潛在感染媒介，在田間造成黃龍病傳播的威脅。; Citrus huanglongbing (HLB) is a destructive disease among citrus industry caused by a phloem-limited bacteria (Candidatus Liberibacter asiaticus, CLas), and it happens in citrus production areas worldwide. With over than 500,000 tons of annual production, Taiwan also suffers from this serious disease. According to the HLB field survey in 2017, there was 31.9% infection in Taiwan. Because all citrus cultivars are susceptible to HLB, it caused great damage on fruit quality and production. As known, the spread of HLB in the field is mainly due to the grafting of infectious scions and insect vector transmission. However, with the help of citrus healthy budwood program which was firstly promoted in 1973, vector psyllids (Diaphorina citri Kuwayama) seems to play an important role in spreading the disease. Researches on transmission ecology of HLB by the psyllid may contribute to the good solution for HLB management. By analyzing new shoot infection status in different weeks, we attempted to find out the movement of CLas from symptomatic old tissues to young leaves among different cultivars, and the results showed that movement in Liucheng cultivar requiring the least time. CLas reached new shoots in only 1 week, and the copy numbers increased slightly. Same movement tendency could be observed in Mandarins (Ponkan and Tankan cultivars), CLas copy numbers rapidly increased after 2 weeks and reach amount of 10,000 copies in week 4, which is also the highest amount in the study. The movement of CLas was much slower in Oroblanco, high ratio of CLas-infected new shoots could only be observed after 3 weeks. Because of the high preference of psyllids to immature foliar tissues, CLas moving to new shoots may offer a good chance for pathogen acquisition. In this study, we also investigated the factors that might influence CLas acquisition. Among different nymphal stages, CLas was firstly detected in the 2nd nymphal stage, and got the highest average copy numbers per psyllid in the 4th and 5th nymphal stages, which had about 130 times in difference. Also, acquisition access period on HLB-infected plant seemed to be another influence factors, percentages of CLas-infected psyllid raised from 30% to 80% when prolonging the period from 14 to 28 days. Moreover, other factors like plant infection status among different cultivars could lead to variation in CLas acquisition. After CLas inoculation by grafting, pathogen acquisition by D. citri firstly occurred after 3 months on infectious Liucheng, 4 and 5 months on Ponkan and Wentan, respectively; while they all happened during asymptomatic phase of infection. As CLas acquired by the psyllids, they followed the open system and circulated in insect bodies. Continuous feeding tests on Murraya spp. made a good way to observe CLas proliferation in D. citri. The results showed that CLas could be still detected until 4 weeks, and it proved the ability of CLas retention in insect vectors. Indicating that once D. citri acquired CLas via feeding, they could probably become a persistent infectious vector, and post the threats to HLB spreading in the fields. Tue, 01 Jan 2019 00:00:00 GMT http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/74388 2019-01-01T00:00:00Z http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/82609 標題: 鳳梨釋迦衰弱病的病原鑑定及落花生簇葉病分子偵測技術改良; Identification of the Pathogen of Custard Apple Decline and Improvement of the Molecular Detection Method for Peanut Witches’Broom 作者: Tung-Yu Lee; 李東祐 摘要: "植物菌質體 (phytoplasmas)係為一群韌皮部侷限的植物寄生性細菌，最早由日本數名科學家Doi等人於西元1967年率先發現，當時認為該病原體為mycoplasma-like organisms (MLOs)。至西元2020年為止，植物菌質體依照16S rDNA序列共分為34個大群 (groups)，其中落花生簇葉病屬於第二大群 (16SrII)的植物菌質體。目前的研究顯示，植物菌質體傳播的方式是經由刺吸式口器的昆蟲，如二點小綠葉蟬、南斑葉蟬等。受植物菌質體感染的寄主植物會出現以下幾種病徵：小葉化、花器葉化、簇葉、矮化、葉片黃化、巨芽等。本研究將進行探討的項目為不同引子對 (primers)對落花生簇葉病之聚合酶連鎖反應 (Polymerase Chain Reaction, PCR)檢測的敏感度差異及近年來疑似由植物菌質體感染的病害——鳳梨釋迦衰弱病——之病原鑑定。本研究的結果顯示，使用本實驗設計的引子對進行聚合酶連鎖反應 (Polymerase Chain Reaction, PCR)比起以往的廣效型引子對P1/P7擁有更清晰、明顯的條帶 (band)，並且以10的倍數進行序列稀釋後，再分別進行PCR反應，結果顯示10000倍稀釋擁有最大的差異度，即使用本實驗設計的引子對Phyto1622 (暫定名)可與傳統廣效型引子對P1/P7產生最大的清晰度及敏感度差異。根據PCR反應及序列定序的結果，鳳梨釋迦衰弱病的病原係為第二大群 (16SrII)的植物菌質體，且與引起落花生簇葉病的植物菌質體有99 %的序列相似度，未來將確定傳播途徑是否與落花生簇葉病有關，以期進行更有效的病害管理及防治。" Fri, 01 Jan 2021 00:00:00 GMT http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/82609 2021-01-01T00:00:00Z http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/69409 標題: 颱風造成臺北地區樹木風倒害因及其管理之研究; Studies on Casual Factors and their Management of Tree Falling by Typhoon at Taipei Areas 作者: Zoen-Wing Leung; 梁臻穎 摘要: 一個適合的樹木健康照護(Plant Health Care,PHC)計畫，應該就不同的國家或地區需要就當地氣候環境，以及逆境例如颱風等，並配合其都市樹木的功能加以規劃。臺灣北部為副熱帶季風氣候，每年夏季均受到颱風吹襲影響，故都市樹木之管理必須包含颱風風害預防的考量。 本研究共診斷調查2015-2017三年間3個中度颱風，於臺北地區所造成之樹木風倒狀況。樹木受風倒者共有637筆，共分成四個風倒級別，分別為全倒286筆（44.9%）、莖斷132筆（29.0%）、枝斷146筆（22.9%）以及傾斜20筆（3.1%），當中以榕樹(Ficus microcarpa)最常見，其後依序為垂榕(Ficus benjamina)、台灣欒樹(Koelreuteria elegans)、白千層(Melaleuca leucadendron)、小葉欖仁(Terminalis mantaly H. Perrier)。並嘗試利用3個颱風對樹木造成的風倒級別及最大切風風速與樹木莖斷及枝斷之關聯性作分析，結果皆未能證明颱風強度及最大切風風速對預測樹木風倒災情有指標性作用。後以樹冠寬與風倒級別作分析，發現樹冠寬／胸徑值比值介乎5.00到19.99之間，較容易受風倒影響。同時，樹冠形狀為展開及尖錐形的樹木，立於人行道旁的行道樹，相比其他樹冠形狀及立地位置的樹木，更容易造成風倒。 在臺北地區颱風造成樹木風倒害因的統計及分析中，資料倒分析分成單一害因及複合害因，經3次颱風資訊比較後，害因常見以樹冠過重、受腐朽影響、生長逆境、患有褐根病為主，樹木淺根、處於風場、白蟻蛀食為副。經卡方統計及類別變項交叉分析之勝算比，可知行道樹、樹木淺根、處於生長逆境的樹木遇上風害時傾向發生全倒。在災後三個月及生長季後進行災後調查，有經災後處理的樹木之生長勢恢復能力明顯比沒有經災後處理的樹木為高。同時，目前的災後處理方法使樹木生長勢恢復能力，無論在四個立地位置之中，皆比期望值高。唯盾柱木(Peltophorum  pterocarpum)、鐵刀木(Senna siamea)、豔紫荊(Bauhinia x blakeana Dunn.)需要進行災後的結構性修剪。 研究同時關注木材腐朽菌問題，在52個樣本中分離出腐朽菌，利用木質素及纖維素分解酵素分泌能力作篩選，分離出腐朽能力最大的六株腐朽菌。接種到三種樹木的木片上皆有不同程度的外觀及乾重損失，經柯霍氏法則驗證後證實腐朽菌於不同木材中皆具有腐朽能力。為了有效篩選出適用的防治藥劑，實驗利用9種不同作用機制及原理的藥劑以10,000倍稀釋濃度先行篩選，再以5種藥劑各12種濃度加入PDA培養基測試以獲得各藥劑對各腐朽菌的半抑制濃度及半致死濃度。 經研究發現菲克利10%乳劑80 ppm、撲克拉25%水基乳劑40 ppm及普克利25%乳劑90 ppm效果最佳，在田間試驗中即利用上述三種配方在每200平方毫米的木材面積下以50mL藥劑處理腐朽菌，於預防及治療測試上都達到90%以上之防治成效。; A flexible Plant Health Care program, PHC, has to consider the difference and extreme climates in countries and cities, such as typhoons, in order to manage the urban trees and maintain their functional contributions. Because of the subtropics monsoon and humid climate, five to six typhoons usually attacked the northern Taiwan every summer. Therefore, typhoon is an essential consideration for urban trees management program in Taipei A 3-year study was from 2015 to 2017, to diagnose and survey the wind-fallen trees caused by three typhoons with intensities not lower than moderate at Taipei areas. A total of 637 cases of wind-fallen trees were diagnosed and recorded. The fallen trees were separated into 4 tree falling levels, including 286 fully fallen cases (44.90%), 132 trunk broken cases (29.04%), 146 twig broken cases (22.91%), and 20 leaning cases (3.13%). Among 637 cases, the dominant tree species in decreasing series, are Chinese banyan (Ficus microcarpa), Benjamin tree (Ficus benjamina), Taiwan golden-rain tree (Koelreuteria elegans), Cajeput tree(Melaleuca leucadendron) and Madagascar almond (Terminalis mantaly H. Perrier). The study tried to reveal the relationship between trees falling levels as well as numbers of trunk broken or twig broken and the maximum wind speed. Results showed that the maximum wind speed played no significant effect on tree falling level or numbers of trunk broken or twig broken. This study, however, discovered that those trees with canopy-width/DBH ratio between 5.00-19.99, or trees with either open shape or sharp canopy shape, are more easily suffered by typhoons. The study also determined the major and minor causal factors of tree falling. The main causal factors usually are trees with too heavy crowns, infected by wood rot fungi, with environmental stress, or with brown root rot disease. The second causal factors are trees with shallow root systems, growing within strong wind field, or attacked by termites. According to the results of Chi-square test and odd ratio analysis, road side trees, trees with shallow root systems, and trees growing with environmental stress, have higher potential for fully falling during typhoons, other than trunk broken or leaning. The survey of efficacy for post-typhoon tree treatment after 3-months or after the next growth season revealed that the present post-typhoon treatment for wind-fallen trees were effective and beneficial for tree vigor recovering. The observed recovered numbers of trees are more than the expected ones, wherever they are growing in one of 4 planting sites. The survey finally suggested that a structural pruning is necessary for yellow flame tree (Peltophorum  pterocarpum), Kassod tree (Cassia siamea), Hong Kong orchid tree (Bauhinia x blakeana Dunn.) after typhoons. The study also focused on the issue of wood rot fungi. After isolating 35 common rot fungi from 52 wind-fallen tree samples, 6 stronger fungi were screened from them by comparing their enzymes activities for lignin and cellulose degradation. Those wood rot fungi were inoculated onto wood chips from 3 tree species for 30 days to determine the weight loss rate caused by the fungi. Results showed that the wood chips showed different level of dry weight loss and different color change. The six selected wood rot fungi can be reisolated and thus fulfilled the rules of Koch’s postulates. In order to find out the most suitable fungicides for wood rot control, a series of experiments were done. Nine fungicides with different action mode or mechanism were chosen and tested each at dilution of 10,000X, to find their mycelium inhibition rates. Then five of them were determined for their half maximum inhibitory and half lethal concentration when each is diluted into 12 serial concentrations in PDA medium, and to test their mycelium inhibition rates against the six wood rot fungi. The study results showed that hexaconazole (10% EC) at 80 ppm, prochloraz (25% EW) at 40 ppm, and propiconazole (25% EC) at 90ppm, are the most effective fungicide formulations for field application. A 50 mL of them were used to spray on maple wood block each for a 200 cm2 wood surface. Results showed that for preventing or curing the wood rot fungi, all three fungicides performed at least a 90% control rate in the field tests. Mon, 01 Jan 2018 00:00:00 GMT http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/69409 2018-01-01T00:00:00Z http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/67336 標題: 非農藥資材防治甘藷基腐病之研究; Study of non-pesticide control on foot rot disease of sweet potato 作者: Hsueh-Hung Chen; 陳學弘 摘要: 甘藷基腐病為近年台灣甘藷栽培中首要危害，本病由 Phomopsis destruens 引起，可造成莖基部產生黑褐色腐爛，向上造成地上部黃化枯萎進而死亡，此外基腐病亦會向下感染甘藷塊根，使甘藷呈水浸狀腐爛，完全失去商品價值。雖然基腐病已於 2016 年公布 2 種正式藥劑，但近年來由於國人對於食品安全、農藥殘留及環境永續等議題日漸重視，化學農藥減少使用已成為普遍趨勢。因此，本研究欲了解台灣北部甘藷栽培現況與基腐病發病情形，同時篩選出具有防治潛力的非農藥資材，並比較其與化學藥劑防治甘藷基腐病的效果。根據調查，2016 年金山萬里甘藷豐收，基腐病造成的損失較少，又因同年一月底全台爆發霸王級寒流，故欲了解低溫逆境是否影響基腐病菌殘存。結果顯示，將基腐病發病藤蔓於 4℃ 低溫處理 5 天病原菌分離率即減至 20%，但至 14 天仍可分離出基腐病菌，分生孢子於低溫處理 14 天發芽率減為約 43%，故推測低溫逆境對基腐病菌的殘存會有一定程度之影響。由 23 種植物精油及 5 種脂肪酸鉀鹽中篩選出肉桂葉與椰子油鉀鹽，並發現將兩者以特定比例混合對基腐病菌有加成的抑制效果，故以此進行後續試驗。甘藷盆苗防治試驗中發現，相較於單獨施用，肉桂葉混合椰子油鉀鹽後對基腐病確實可達到較佳的防治效果；此外，施用腐絕、待克利、普克利、菲克利及貝芬菲克利亦可降低疾病嚴重度；然而施用拮抗微生物於甘藷盆苗防治試驗卻未見防治成效。將帶病扦插苗在種植前先浸泡防治，結果顯示腐絕或肉桂葉混合椰子油鉀鹽的處理均可在種植後 40 天及 60 天降低其疾病嚴重度。甘藷塊根防治試驗的結果則顯示，肉桂葉混合椰子油鉀鹽、腐絕、待克利、普克利、貝芬菲克利均可顯著減少甘藷塊根基腐病之疾病嚴重度。總結而言，肉桂混合椰子油鉀鹽確實對甘藷基腐病具有防治潛力。未來可持續觀察氣候因子與基腐病發生之關聯，並探討非農藥資材或化學藥劑於田間防治的施用時機及頻率，以達到更好的防治效果。; Foot rot disease, caused by Phomopsis destruens, is the most important disease of sweet potato in Taiwan. The symptoms include stem rot, leaf yellowing, plant wilt and storage tuber rot. In 2016, two fungicides are officially recommended for controlling this disease. However, due to the growing concern about food safety, pesticide residues and environment sustainability in recent years, reducing the use of synthetic pesticides has become a general trend. Therefore, the aim of this study is to investigate the cultivation type and incidence of foot rot disease in northern Taiwan, and to screen some non-pesticides with potential to control foot rot disease of sweet potato. According to official data, it was a year of bumper harvest for sweet potato in Jinshan and Wanli area in 2016. While the loss of yield caused by foot rot disease was minor in that year. Due to the outbreak of an extremely cold front happened in January in 2016, this study tried to elucidate whether low-temperature could affect the survival of pathogens. The results showed that after treating diseased tissues with 4℃ low temperature for 5 days, isolation rate of the pathogen had reduced to 20%, but could be isolated after 14 days. The conidia germination rate of P. destruens was about 43% after low-temperature treatment for 14 days. Thus, it was assumed that low temperature has important influence on the survival of pathogen. The cinnamon leaf oil (CLO) and the potassium salt of coconut oil (COPS), selected from 23 essential oils and 5 potassium salts of fatty acid (FAPS), were found to have an additive inhibition effect on P. destruens after mixed with a specific ratio, which was used therefore in this study. In the pot assay, results indicated that CLO + COPS can achieve better control effect as compared with control or that applied alone. The fungicides including thiabendazole, difenoconazole, propiconazole, hexaconazole and carbendazim + hexaconazole also showed good control efficacy for foot rot disease. However, the treated antagonistic microorganisms did not show controlling efficacy for foot rot disease. In the dipping therapy assay for diseased seedlings, results revealed that both thiabendazole and CLO + COPS treatments can reduce the disease severity after 40 and 60 days cultivation. In the dipping control assay of sweet potato storage tubers, CLO + COPS, thiabendazole, difenoconazole, propiconazole, and carbendazim + hexaconazole showed significantly decrease of severity of foot rot disease. In conclusion, CLO + COPS does have potential to control foot rot disease. The relationship between climate factors and incidence of foot rot disease should be observed continuously in the future. In order to achieve better control efficacy, the timing and frequency of treatment including non-pesticides and pesticides should also be further studied. Sun, 01 Jan 2017 00:00:00 GMT http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/67336 2017-01-01T00:00:00Z