春季茶蚜种群动态及与茶树、食蚜蝇等天敌化学通讯联系

【作者】 周成松；

【导师】 韩宝瑜； 江昌俊；

【作者基本信息】 安徽农业大学 ， 茶学， 2003， 硕士

【摘要】 茶蚜是我国和近邻越南、缅甸等产茶国的重要茶树害虫之一。其刺吸幼嫩茶梢，排泄“蜜露”孳生烟煤病，引发茶煤病，并具有较强的迁飞习性。本文调查了春季茶蚜种群动态，探究了化学信息物质在茶树—茶蚜—食蚜蝇等天敌间的通讯效应，期望为茶蚜的无公害防治提供依据。 调查发现茶蚜在3月29日到4月13日期间种群数量急剧上升。4月3日查得茶蚜数量最高；而天敌的种群动态与茶蚜种群动态有一时滞，虫口高峰稍延迟，出现在4月8日以后。 分析计算了茶蚜天敌群落的物种丰富度、多样性指数、均匀度和优势度指数，发现群落物种丰富度由2到7变化较大。多样性指数与均匀度指数在春季呈现增长趋势，优势度指数早春较高，之后逐步降低。 计算了茶蚜及其天敌的时间、空间生态位宽度和生态位重叠。茶蚜的时间生态位较小。几种天敌中以食蚜蝇的生态位宽度最小，蜘蛛的生态位宽度最大，而与茶蚜的生态位重叠度以蜘蛛的最小，食蚜蝇的最大。龟纹瓢虫、异色瓢虫、七星瓢虫、大草蛉、中华草蛉间的差别不大。对空间生态位的研究发现茶蚜的空间生态位较低，蜘蛛的空间生态位宽度最高。而食蚜蝇的空间生态位最窄，草蛉类空间生态位宽度也偏小。几种天敌中，以食蚜蝇与茶蚜的空间生态位重叠度最大，其次为三种瓢虫。蜘蛛、中华草蛉和茶蚜的空间生态位重叠度最小。 以四臂嗅觉仪测定了有翅茶蚜对15茶树挥发物的行为反应。结果表明，在四臂嗅觉仪中有翅茶蚜对多数味源物都有明显的行为反应，当供试剂量为10^-4ug／ul时，对有翅茶蚜有活性的味源物为：顺-3-己烯-1-醇、乙酸顺-3-己烯酯、反-2-己烯醛、反-4-己烯-1-醇、烯丙基异硫氰酸酯、橙花醇、α-石竹烯、芳樟醇、己醛、苯甲醛、正-辛醇、水杨酸甲酯；并且，这些味源物中，除烯丙基异硫氰酸酯和α-石竹烯外，各味源物对茶蚜的作用均达到极显著水平。当供试剂量为10^-2ug／ul时，对有翅茶蚜有活性的物质与10^-4ug／ul浓度下的相同；各味源物中，除苯甲醛外，对茶蚜的引诱活性均达到极显著水平。不同味源物间的引诱作用存在显著差异。新复极差测验发现，在两种供试剂量下均以水杨酸甲酯的诱效最强。芳樟醇、α-石竹烯在不同供试剂量时各自的作用有显著差异。芳樟醇在低剂量时呈现正引诱效应，高剂量时呈现负引诱效应；α-石竹烯在10^-2ug／ul的作用强于10^-4ug／ul浓度时的作用。 采用Y形嗅觉仪，以顺-3-己烯-1-醇、乙酸顺-3-己烯酯、反-2-己烯-1-醇、芳樟醇、反－2－己烯醛、反－4己烯－1醇、罗勒烯、香叶醇、烯丙基异硫氰酸酯、橙花醇、O－石竹烯、己醛、苯甲醛、正－辛醇、水杨酸甲酯为味源，其中基本上为蚜害茶梢挥发物，各设10一、分山、10一、以UI两个处理浓度，以生物测定方法检测了它们对食蚜蝇的引诱效应。结果发现，在 10、灿山浓度时，食蚜蝇对反刁－己烯－1－醇、芳樟醇、反－2－己烯醛、罗勒烯、香叶醇、橙花醇、正辛醇、水杨酸甲酯有显著的趋性。在10”二g巾1浓度时，食蚜蝇对己醛和苯甲醛有显著趋性，而对其它味源物的趋性不显著。还检测了茶蚜天敌大草蛤对上述味源物的趋性。在10一、川浓度下，大草岭显著趋向于味源物己醛和正辛醇，对其他味源物没有明显的行为反应。在10－h以UI浓度下，大草岭显著趋向于反上－己烯才醇、香叶醇和己醛，而对其他昧源物没有反应。其中反－2－己烯刁醇为绿叶气味，香叶醇为单酝类，并且在蚜害茶梢中存在。 本研究认为，茶蚜为茶树卜较转化的、趋嫩为害的、有一定迁飞习性的害虫，春季采摘春茶时其种群数量有影响，其天敌较多。茶梢释放的顺－3－己烯－1－醇、反－2－己烯醛等“绿叶气味”引诱茶蚜，蚜害茶梢挥发物苯甲醛、反－2－己烯醛、水杨酸甲酯等组分显著地引诱食蚜蝇等天敌。如何有效地利用化学信息物质防治茶蚜值得深入研究。更多还原

【Abstract】 Tea aphid (Toxoptera aurantii Boyer) is one of the serious pests in our country and other neighboring tea-producing countries, like Vietnam and Burma. It pierces and sucks young tea shoots, and excretes honeydew infesting Neocapnadium theae Kara. Again it has a strong migrating habit. In order to find some useful method in the uncontaminated management of tea aphid, we made a continuous survey on the population dynamics of tea aphid in spring, and studied the communicating function of semiochemicals in the tritrophic level of tea plant-tea aphid-tea aphid’s natural enemies.Tea aphid’s population increased sharply from March 29 to April 13. Population peak emerged around April 3. There was a time lag between the natural enemies’ population and tea aphid’s population. Natural enemies’ population peak was found on 8 April.Richness, diversity indices, evenness degree and dominant degree of the natural enemies’ community were calculated and analyzed. Species richness of the community changed from 2 to 7. Diversity indices and evenness degree increased in spring, domination degree was high in early spring, then, decreased.Temporal niche width, spatial niche width and the overlap of the two niches of tea aphid and its natural enemies were calculated. Temporal niche width of tea aphid was small. Spiders’ temporal niche width was the greatest among all the natural enemies, however, it had the smallest niche overlap with tea aphid. Syrphids’ niche overlap with tea aphid was the greatest. No significant difference among Propylaeajapoinca (Thunberg), Lets axyridis (Pallas), Coccinella septempunctata L., Chrysopa septempunctata Wesmeal and C. sinica Tjedea was found. Tea aphid had a small spatial niche width. Spiders had the greatest one among all the natural enemies, while syrphids had the smallest. Lacewings’ niche width was also small. Syphids had the greatest niche overlap with tea aphids, beetles’ had smaller niche overlap with tea aphid, and spiders and lacewings had the smallest niche overlap with tea aphid.The behavioral reactions of winged tea aphid to 15 various odor sources were" tested in a four-armed olfactometer. Winged Tea aphid had significant olfactory responses to most of the odor sources in the olfactometer. At 10-4ug/ul dose level, those odor sources are: (Z)-3-hexen-l-ol, (Z)-3-hexen-l-ol acetate,Trans-2-hexen-l-yl, (E)-4-hexen-l-ol, Linalool, Aallyl isothiocyanate, Nerolidol, a -caryophyllene, Hexenal, Benzaldehyde, n-octanol, Methyl Salicylate. Those odor sources also have significant effects on tea aphid at 10-2ug/ul dose level. Attracting ability of different ordours varies. New multiple range test found that, among all the odor sources, Methyl Salicylate had the most significant effect on tea aphid at both of the two dose level. It was also found that the effect of Linalool and a -caryophyllene had varied effects at the two dose levels respectively. The linalool affected alatae adversely at the two consistency levels i.e. it attracted tea aphid significantly at 10-4ug/ul, while it affected tea aphid adversely at 10-2ug/ul; a -caryophyllene was found to be more attractive to alatae at 10-2ug/ul than at 10-4ug/ul.Y-shaped olfactometer was used to test taxis of syrphid Sphaerophoria menthastri L. and lacewings to various odor sources. Those odor sources are: (Z)-3-hexen-l-ol, (Z)-3-hexen-l-ol, acetate, (E)-2-hexen-l-ol, Linalool, Trans-2-hexen-l-yl, (E)-4-hexen-l-ol, l,3,6-octatriere-3,7- dimethyl, Geraniol, Aallyl isothiocyanate, Nerol, a -caryophyllene, Hexanal, Benzaldehyde, n-octanol, Methyl Salicylate. Most of them are volatiles from tea aphid infested tea shoots. It was found that syrphids were attracted at 10-4ug/ul dose level to odor sources such as (E)-2-hexen-l-ol, Linalool, Trans-2-hexen-l-yl, l,3,6-octatriere-3,7-dimethyl, Geraniol, Nerol, n-octanol, Methyl Salicylate. At 10-2ug/ul dose level, syrphids had significant taxis towards Hexenal and Benzaldehyde. Y-shaped olfactometer was also used to test taxis of lacewing (Chiysopa septempunctata Wesmeal), one of tea aphid’s e更多还原