【作者】 黄永红；

【导师】 易干军； 王仁才；

【作者基本信息】 湖南农业大学 ， 果树学， 2011， 博士

【摘要】 香蕉(Musa spp.)既是重要的经济作物也是重要的粮食作物,是位于水稻、小麦、玉米之后的第四大粮食作物。目前,世界上大约有127个国家和地区种植香蕉。中国是世界香蕉原产地之一,有3000多年的种植历史。2009年中国香蕉种植面积达466.65万亩,产量达820多万吨,已成为世界上主要的香蕉生产大国之一。目前香蕉产业现已成为中国南方热作产业的支柱产业之一,对中国南方农村经济的发展和热区农民收入水平的提高发挥了举足轻重的作用。香蕉枯萎病是最具有毁灭性的植物病害之一。由尖孢镰刀菌古巴专化型(Fusarium oxysporum f. sp. cubense, Foc)引起。该病已在亚洲、非洲、澳洲、美洲热带地区的香蕉园中普遍发生。香蕉枯萎病的大面积发生和流行,对全球香蕉产业造成了巨大的损失。针对该病,国内外科研工作者进行大量的工作,也取得了丰硕成果,但遗憾的是至今还没有一种有效的防控措施广泛应用于商业性生产实践中。所幸的是,我们在广州地区香蕉生产实践中发现,在商业性栽培韭菜(Allium tuberosum)的地块中轮作香蕉,可以有效地降低香蕉枯萎病的发生率,减轻发病指数。本研究就是在此重大发现的基础上,结合田间试验、盆栽试验及实验室工作,对韭菜防控香蕉枯萎病的效果进行了研究,并对其防控机制进行了探讨,取得了结果如下：1.2006-2009年的大田试验表明：在商业化生产韭菜2-3年的地块轮作香蕉,第一年巴西(AAA)和广粉1号(ABB)香蕉枯萎病平均发病率分别为1.7%和2.7%,而对照分别为52.0%和36.7%。2007年韭菜地轮作广粉1号,发病率和病情指数分别降低96.6%和96.7%；2008年韭菜地轮作广粉1号,发病率和病情指数分别降低92.3%和94.2%；2009年韭菜地轮作广粉1号,发病率和病情指数分别降低88.4%和91.2%；商业性生产的韭菜地间作香蕉对香蕉枯萎病的防控效果几乎可以达到100%。田间试验表明：在商业化生产韭菜2-3年的地块中种植香蕉,对枯萎病的发生具有极高的防控效果,间作模式的防控效果可以高达100%。2.通过三轮人工接菌盆栽试验研究韭菜对香蕉枯萎病发率及病情指数的影响：第一轮试验表明,韭菜残体对巴西香蕉的病情抑制率高达86.9%,对广粉1号粉蕉的病情抑制率高达93.4%。第二轮试验表明：在人工接菌基质试验中,韭菜残体和韭菜提取液对巴西香蕉病情抑制率分别为54.4%和63.6%,对广粉1号粉蕉的病情抑制率分别为75.0%和62.5%；在自然带菌田园土中,韭菜残体和韭菜提取液对巴西香蕉病情抑制率分别为78.6%和64.3%,对广粉1号粉蕉的病情抑制率分别为44.4%和66.7%；第三轮试验表明,在人工接菌基质试验中,韭菜残体处理对巴西香蕉和广粉1号粉蕉的病情抑制率为61.8%和80.7%,在自然带菌田园土中,韭菜残体处理对巴西香蕉的病情抑制率为81.1%。3.在实验室进行了韭菜粗提取液对香蕉枯萎病菌生理4号小种(Foc4)生长的抑制作用发现：10%的韭菜粗提取液在平板上对Foc4菌丝生长的抑制率为64.6%；韭菜提取液能破坏Foc4菌丝结构；不同浓度的韭菜粗提取液处理能显著抑制Foc4孢子的萌发,10%能完全抑制其萌发。共培养实验说明,在PDA共培养体系中,30%的韭菜提取液对Foc4的孢子增殖具有高度的抑制作用,抑制率为91.2%,对Foc4孢子的致死率为87.0%。在无营养的水共培养体系中,低浓度韭菜粗提取液对能在一定程度上促进Foc4孢子的增殖,韭菜粗提取液对Foc4孢子的致死率为98.6%。试验表明：韭菜提取液能够有效地抑制Foc4菌丝的生长,对菌丝结构产生破坏作用；能显著抑制Foc4孢子的萌发,并能对Foc4孢子产生显著的致死作用。4.研究韭菜处理对香蕉根际土壤微生物数量和酶活性的影响。试验表明：Foc4处理对微生物总量及细菌(B)数量影响不大,但真菌(F)数量提高了2.72倍,放线菌(A)数量降低了42.29%,B/F值降低了89.58%,A/F值降低了89.41%；在接菌和不接菌情况下,韭菜处理都显著提高了微生物的数量,不接菌情况下,韭菜处理分别提高微生物总量277.70倍、提高细菌数量288.72倍,提高真菌数量2.85倍,提高放线菌数量2.14倍、提高B/F值575.10倍；在接菌情况下,韭菜处理分别提高微生物总量314.82倍、提高细菌数量347.18倍、提高真菌数量3.17倍、提高放线菌数量1.65倍、提高B/F值在81.28倍；韭菜处理还能显著提高根际土壤酶活性。试验表明：韭菜处理能显著提高根际土壤微生物数量,而且能显著提高根际土壤酶活性,这与韭菜处理提高香蕉抗枯萎病能力密切相关。更多还原

【Abstract】 Banana (Musa spp.) is an important economic crop, and also a staple food, ranking the fourth after rice, wheat and corn. At present, bananas are planted in about 127 countries and regions around the world. China is one of the birth places of banana and has a cultivation history of over 3000 years. In 2009, the planting areas in China are about 311,100 ha (4,666,500 Mu), and the yields are up to over 8.2 million tons, making China one of the main countries producing banana. Now, banana industry has been devolved into one of pillar industries and plays an important role in development of rural economy and in increase of farmer income.Fusarium wilt, one of the most destructive plant diseases, is caused by Fusarium oxysporum f. sp. Cubense. The disease has been spread in banana plantations in Asia, Africa, Austria, and tropical America. Since the disease has been widely spread, it caused a great loss around the world. Scientists around the world have worked hard on Fusarium wilt for many years and have made great progresses. Unfortunately, effective control measure has not been found and widely applied in banana commercial production. However, an effective way to control the fetal disease by rotating bananas with Chinese leek (Allium tuberosum) has been widely used in commercial production of banana in Panyu area, Guangzhou, China. The Chinese leek-banana rotation system efficiently decreased the disease incidence (DI) and disease severity index (DSI). Based on the great discovery, we focused on the effects and mechanism of Chinese leek on control of Fusarium wilt by combinating field trials, artificial inoculation of potted banana in greenhouse and the laboratory experiments. The main results are followings:1. Field trials were carried out between 2006 and 2009. The results showed that average Fusarium wilt incidence of Baxi (AAA) and Guangfen No.1 (ABB) in the fields where Chinese leek had been commercially grown for 2-3 years were 1.7% (52.0% in control) and 2.7%(36.7% in control) in the first year, respectively. In 2007, the DI and the DSI of Guangfen No.1 (ABB) rotated with Chinese leek were reduced by 96.6% and 96.7%. In 2008, the DI and the DSI of Guangfen No.1 (ABB) rotated with Chinese leek were reduced by 92.3% and 94.2%. In 2009, the DI and the DSI of Guangfen No.1 (ABB) rotated with Chinese leek were reduced by 88.4% and 91.2%. None of the over 2,500 Baxi (AAA) plants intercropped in the fields where Chinese leek had been grown for 2 years were infected and showed visible symptom. And the control effect was 100%.2. Three rounds trials of potted banana planted in peat soil inoculated with Foc4 or the field soil naturally inoculated with Foc were performed in greenhouse to identify the effects of Chinese leek on the control of Fusarium wilt disease. In the first round trial, the suppression incidence of DIS in potted Baxi(AAA) planted in peat soil treated by leave pieces of Chinese leek was 86.9%, and that in Guangfen No.1 (ABB) planted treated by leave pieces of Chinese leek was 93.4%. The second round trial, the suppression incidences of DIS in Baxi (AAA) planted in the peat soil treated by leave pieces of Chinese leek and crude extract of Chinese leek were 54.4% and 63.6%; and those in Guangfen No.1 (ABB) planted in peat soil treated by leave pieces of Chinese leek and crude extract of Chinese leek were 75.0% and 62.5%. In the field soil naturally inoculated with Foc, the suppression incidences of DIS in Baxi (AAA) treated by leave pieces of Chinese leek and crude extract of Chinese leek were 78.6% and 64.3% and those in Guangfen No.1 (ABB) treated by leave pieces of Chinese leek and crude extract of Chinese leek were 44.4% and 66.7%; In the third trial, in the peat soil artificially inoculated with Foc4, the suppression incidences of DIS in Baxi (AAA) and Guangfen No.1 (ABB) treated by leave pieces of Chinese leek were 61.8%和80.7%, and in the field soil naturally inoculated with Foc, the suppression incidences of DIS in Baxi (AAA) treated by leave pieces of Chinese leek were 81.1%.3. The inhibitory effects of crude extract of Chinese leek on the growth of Foc4 were studied in the laboratory. The results showed that 10% of the crude extract of Chinese leek suppressed the growth of Foc4 mycelium by 64.6% on the Petri dishes. Chinese leek greatly damaged the structures of Foc4 mycelium. Various concentration of crude extract of Chinese leek significantly suppressed the germination of Foc4 spores. The concentration of 10% can completely suppressed the germination of the spores. The co-culture of Foc4 and the crude extract of Chinese leek on the shaking table suggested that in the PDA culture system,30% of crude extract of Chinese leek can suppressed the proliferation of Foc4 spores by 91.2%, and caused the spore death by 87.0%; And that in the water culture system,,low concentration of Chinese leek extract can increase the proliferation of the spores in some extent.The lethal incidence was 98.6%.4. The microorganisms and enzyme activity in rhizosphere soil of banana plants treated by Foc4 or Chinese leek were also studied. The results showed that Foc4 little affected total amount of the microorganisms and bacterial, but significantly increased the amount of the fungi by 2.72 times. The amount of actinomycete decreased by 42.29%, the ratio of bacterium and fungi (B/F) decreased by 89.58% and the ratio of actinomycete and fungi (A/F) decreased by 89.41%. Chinese leek significantly increased the amount of the microorganism in the rhizosphere soil of banana plants inoculated with or not inculcated Foc4. Without the existents of Foc4, Chinese leek treatment increased the total amount of microorganism by 277.70 times, bacterium by 288.72 times, fungi by 2.85 times, actinomycete by 2.14 times, B/F by 575.10 times; In the condition of inoculation with Foc4, Chinese leek Chinese leek treatment increased the total amount of microorganism by 314.82 times, bacterium by 347.18 times, fungi by 3.17 times, actinomycete by 1.65 times, B/F by 81.28 times; In addition, Chinese leek also significantly increased the enzyme activities in the rhizosphere soil of banana plants such as catalase, polyphenoloxidase, phosphatase, invertase, urease and cellulose.更多还原