柠檬内定殖的昆虫病原真菌对其生长及柑橘木虱的影响
发布时间：2020-06-20 07:00
【摘要】：本研究测定了白僵菌属(Beauveria)、棒束孢属(Isaria)和绿僵菌属(Metarhizium)的分离菌株在柠檬中的定殖能力,并且进一步探讨了昆虫病原真菌在柠檬中定殖对柠檬生长及其害虫柑橘木虱的存活率、生长发育和繁殖率等生理指标的影响。对昆虫病原真菌的分离菌株进行致病力测试后,筛选得到有强侵染力的菌株。致病力研究中,不同菌株处理柑橘木虱5天后,成虫死亡率达到60%;其中两个菌株处理柑橘木虱7天后,成虫死亡率分别达到92%和95%在叶面接种菌株后,昆虫病原真菌定殖于柠檬的叶、茎、根等不同组织中,其中白僵菌的两个菌株在柠檬中定殖时间长达12周。本研究发现,在柠檬中接种病原真菌所使用的方法以及柠檬的树龄对定殖率有显著影响。在同一树龄的柠檬中,使用叶面接种的昆虫病原真菌定殖率高达58.3%,比使用土壤浸润接种的25%高;另外,在低树龄的柠檬中分再分离到昆虫病原真菌的概率更高。白僵菌定殖柠檬幼苗后,树高以及叶片数都显著大于无白僵菌定殖植株。测定内生真菌定殖于柠檬幼苗后对柑橘木虱存活率、生长发育以及繁殖力的影响。研究发现,白僵菌作为内生菌定殖于柠檬后,柑橘木虱的死亡率升高,卵的孵化率、若虫的羽化率以及雌虫的繁殖率都有显著下降。内生的白僵菌致使3个连续世代的柑橘木虱死亡15%,卵的孵化率和若虫羽化率显著下降。结果表明,雌虫在含有内生真菌的柠檬上取食后,产卵量比在无内生菌定殖柠檬上取食的低。另外,从田间被虫生真菌感染的柑橘木虱体内分离菌株,并通过形态学结合ITS序列分析鉴定菌株。使用最大似然法和最大简约法构建该菌的系统发育树后鉴定确认该菌株属于棒束孢属真菌。将分离菌株回接到柑橘木虱的成虫和若虫中,木虱所表现症状和田间观察到的一致。爪哇棒束孢(Isaria javanica)的两个分离菌株中的一株(IJACP)通过叶面接种后能够成功定殖在柠檬的茎和叶中。此外,本研究测定了不同的接种方法对昆虫病原真菌在柠檬中定殖率的影响。结果表明,结合叶面接种的种子浸润接种的双接种法的定殖率比单一的叶面接种或种子浸润接种的定殖率高。综上所述,本研究阐述了昆虫病原真菌在柠檬幼苗中定殖不仅能够提高株高和叶片数,还能够降低柑橘木虱对柠檬的为害。本研究为柑橘木虱的防治提出了一个利用昆虫病原真菌间接防治害虫的一种新的生物防治措施。
【学位授予单位】：福建农林大学
【学位级别】：博士
【学位授予年份】：2019
【分类号】：S436.66;S476.12
【图文】：
Fig. 1-1. Predators of Asian citrus psyllid (Diaphorina citri); (A) Coccinellid predatory beetles Harmonia axyridis(B) Parasitic wasp Tamarixia radiata (Photo by J.K Clark, M. A Hoy). Source[1]图 1-1. 柑橘木虱的天敌昆虫：（A）异色瓢虫；（B）亮腹釉小蜂1.5.5 Entomopathogenic fungi as bio-control agents for the management of Asiancitrus psyllid and other economic pests of citrusEntomopathogenic fungi (EPF) when incorporated as part of an Integrated Pest Managementprogram have been shown to be effective in managing pest populations[165]. The populations ofimmigrant insect pests on the plant surface and in the soil can be effectively suppressed by sprayingEPF in a classical biological control strategy[166]. EPF has a wide host range and vary considerablyin their mode of action and virulence, therefore are the most effective biological control agents[167].Several entomopathogenic fungal species have been evaluated as microbial control agents against
2-1. Survival probability of Asian citrus psyllid adults exposed to Beauveria bassiana strains (BBB Fafu-13 and BB Fafu-16) and Metarhizium anisopliae (MA Fafu-1) and the control at differenpost-exposure (1-7 days).图 2-1.白僵菌菌株以及绿僵菌侵染对柑橘木虱存活率的影响 Microscopic examinationour fungal strains induced similar disease symptoms in healthy adult D. citri. All theced mycelium outgrowth in dead insects within 1-3 days of psyllid exposure. Hol outgrowth caused by BB Fafu-13 strain (Fig. 2-2) appears earlier that the rest os, while MA Fafu-1 and BB Fafu-16 are usually 12 18 h later than strains BB Fafuafu-13. Microscopic examination was done to observe the development of external symult ACP post-inoculation with fungal conidial suspensions of each of the strains at dincubation times (24, 36, 48, 72, 84 and 96 h PI) (Fig. 2-2).
本文编号：2722052
【学位授予单位】：福建农林大学
【学位级别】：博士
【学位授予年份】：2019
【分类号】：S436.66;S476.12
【图文】：
Fig. 1-1. Predators of Asian citrus psyllid (Diaphorina citri); (A) Coccinellid predatory beetles Harmonia axyridis(B) Parasitic wasp Tamarixia radiata (Photo by J.K Clark, M. A Hoy). Source[1]图 1-1. 柑橘木虱的天敌昆虫：（A）异色瓢虫；（B）亮腹釉小蜂1.5.5 Entomopathogenic fungi as bio-control agents for the management of Asiancitrus psyllid and other economic pests of citrusEntomopathogenic fungi (EPF) when incorporated as part of an Integrated Pest Managementprogram have been shown to be effective in managing pest populations[165]. The populations ofimmigrant insect pests on the plant surface and in the soil can be effectively suppressed by sprayingEPF in a classical biological control strategy[166]. EPF has a wide host range and vary considerablyin their mode of action and virulence, therefore are the most effective biological control agents[167].Several entomopathogenic fungal species have been evaluated as microbial control agents against
2-1. Survival probability of Asian citrus psyllid adults exposed to Beauveria bassiana strains (BBB Fafu-13 and BB Fafu-16) and Metarhizium anisopliae (MA Fafu-1) and the control at differenpost-exposure (1-7 days).图 2-1.白僵菌菌株以及绿僵菌侵染对柑橘木虱存活率的影响 Microscopic examinationour fungal strains induced similar disease symptoms in healthy adult D. citri. All theced mycelium outgrowth in dead insects within 1-3 days of psyllid exposure. Hol outgrowth caused by BB Fafu-13 strain (Fig. 2-2) appears earlier that the rest os, while MA Fafu-1 and BB Fafu-16 are usually 12 18 h later than strains BB Fafuafu-13. Microscopic examination was done to observe the development of external symult ACP post-inoculation with fungal conidial suspensions of each of the strains at dincubation times (24, 36, 48, 72, 84 and 96 h PI) (Fig. 2-2).
本文编号：2722052
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