【作者】 马超；

【导师】 尤民生； 陈少波；

【作者基本信息】 福建农林大学 ， 农业昆虫与害虫防治， 2009， 硕士

【摘要】 氮是植物和节肢动物生长发育过程中不可缺少的营养元素之一,长期大量施用氮肥是引起害虫猖獗为害的主要原因之一。目前有关施氮对植食性昆虫生态适应性影响的研究还很少。本文研究了不同施氮量对乌龙茶幼龄茶树(Camellia sinensis)及茶蚜(Toxoptera aurantii Boyer)生理生化特性的影响,分析了茶树、茶蚜生理生化特性之间的关系,探讨不同施氮水平胁迫下连续多代茶蚜种群的耐饥力、药剂敏感性和极端温度忍耐性的变化,明确施氮对茶蚜种群生态适应性的影响,以期揭示害虫猖獗的机理。试验结果如下:1不同施氮量对茶树生理生化特性的影响施氮对不同树龄的茶树的生理生化特性的影响有所不同。随着施氮量的增加,一年生和二年生的茶树全氮和咖啡碱的含量以及一年生茶树硝态氮、游离氨基酸和蛋白含量显著提高,二年生茶树硝态氮含量和所有树龄茶树碳氮比则显著降低;而两年生、三年生茶树游离氨基酸含量、三年生茶树可溶性糖含量、两年生茶树茶多酚含量与施氮量呈二次曲线回归关系;但其它树龄的其它生理生化指标与施氮量无显著相关。全氮含量和碳氮比可以较好反映幼龄茶树的生理品质,但它们都不能反映茶梢茶多酚含量的变化。因此,在研究茶树的生理品质与植食性昆虫的关系时,应将全氮含量、碳氮比和茶多酚含量都作为最重要生理指标。2不同施氮量对茶蚜主要生理指标的影响前三代茶蚜可溶性蛋白含量随着施氮量的增加而显著增加,随着代数的增加其增加速度逐渐减慢;而多代茶蚜可溶性蛋白含量与施氮量无显著相关。各代茶蚜粗脂肪含量均与施氮量无显著相关。前三代茶蚜羧酸酯酶(CarE)活力施氮量增加而显著提高,而二代茶蚜乙酰胆碱酯酶(AChE)活力与施氮量呈二次曲线回归关系,但其它代的茶蚜CarE和AChE活力以及各代茶蚜谷胱甘肽-S-转移酶(GSHs)活力均与施氮量无显著相关。3茶蚜、茶树生理生化指标之间的关系第二代茶蚜蛋白质含量与茶树游离氨基酸含量显著正相关,多代茶蚜蛋白质含量与茶树可溶性蛋白含量显著负相关,第一、三代及多代茶蚜的蛋白质含量与茶树游离氨基酸含量无关。前三代茶蚜蛋白质含量与茶树可溶性蛋白含量无关。前三代茶蚜CarE活力与茶树含氮量显著正相关,多代茶蚜CarE活力与茶树含氮量显著负相关。而茶蚜AChE和GSHs活力均都与茶树含氮量无关。整个试验期间茶蚜各个主要生理指标与其对应的茶树主要生理指标之间的关系的研究结果表明,茶蚜蛋白质含量与茶树总碳和咖啡碱的含量显著正相关,茶蚜粗脂肪含量与茶树咖啡碱含量显著负相关,茶蚜AChE活力与茶树可溶性糖含量显著正相关,茶蚜CarE活力与茶树全氮和可溶性糖的含量显著正相关,与茶树硝态氮含量显著负相关,茶蚜GSHs活力与所测茶树主要生理指标无关。4不同施氮量对茶蚜种群生态适应性的影响不同施氮量对茶蚜种群耐饥力的影响随代数的增加逐渐增强;茶蚜种群耐饥力随着施氮量的增加而提高,但过高施氮又使其下降。前三代茶蚜种群对吡虫啉的敏感性随着施氮量的增加而降低,但过高施氮又使其增加;而多代茶蚜种群对吡虫啉的敏感性却随着施氮量的增加而增加。前三代茶蚜种群对联苯菊酯的敏感性随着施氮量的增加显著降低;而多代茶蚜种群对联苯菊酯的敏感性随着施氮量的增加呈现先下降、后上升的趋势,在中度施氮时(1.5 g/pot)其敏感性最低。施氮对一代茶蚜种群低温(0℃)忍耐性无显著影响;而二代及以后的茶蚜种群低温忍耐性随着施氮量的增加而提高,但过高施氮又使其降低。施氮对一代茶蚜种群40℃忍耐性无显著影响;二代和三代的茶蚜种群40℃高温忍耐性随着施氮量的增加而提高;中度施氮(1.5 g/pot)和高施氮(2.5 g/pot)显著提高多代茶蚜种群40℃忍耐性,其它施氮量则无显著影响。各代茶蚜种群45℃高温忍耐性随着施氮量的增加而提高,但过高施氮又使其降低;在中度施氮(1.5 g/pot)时达到最高。更多还原

【Abstract】 Nitrogen (N) is one of the most important nutritional elements for growth and development both of tea plants and arthropods. The excessive application of nitrogen fertilizer is considered as a key factor of rampancy of pest herbivores. But little was known about the effects of nitrogen application on ecological fitness of herbivores. In this thesis, we studied the effects of rate of nitrogen application on physiology of Oolong tea plant (Camellia sinensis) and ecological fitness of tea aphids (Toxoptera aurantii Boyer). The results were as follows:1. Effects of nitrogen application on tea physiologyN application differently affected tea physiology of different year tea plants: with N application increasing, total N and caffeine of annual and biannual tea increased as well as nitrate N, free amino acids and total proteins of annual tea, while C/N and biannual tea nitrate N significantly decreased and a conic regression relationship was found between N application and free amino acids of biannual and 3-year-old tea, 3-year-old tea soluble sugars and tea polyphenols of biannual tea.Nitrate N, free amino acids, soluble proteins and caffeine had a significant positive correlation with total N, but C/N negative, while a conic regression relationship was found between soluble sugars and total N, and tea polyphenols independent. Free amino acids, soluble proteins, soluble sugars and caffeine had a significant negative correlation with C/N, while nitrate N and tea polyphenols independent.2. Effects of nitrogen application on physiology of tea aphidsSoluble proteins of the first generations’aphids(G1) remarkably increased as N application increased, with lower increase rates on later generations, while that of aphids above GN was non-related with N application neither was crude fat.Nitrogen application complicatedly affected aphids’insecticide susceptibility: it had significant effects on carboxlesterase (CarE) activity of the first generations’aphides and acetycholineterase (AChE) activity of G2 aphids, but no effect on CarE or AChE activity of aphids above GN or on glutathione s-transferase (GSHs) activity.3. Physiological relationships between tea plants and tea aphidsProtein content of G3 aphids had a significant correlation with tea free amino acids, while that of aphids above GN had a significant negative correlation with tea soluble proteins, and that of aphids of G1, G2 and above GN was independent of tea free amino acids. No correlation was found between tea soluble proteins and protein contents of the first three generations’aphids. AChE activities of G1, G2, G3 aphids had a significant positive correlation with tea N contents, while CarE activity of aphids above GN negative, and AChE and GSHs activities of aphids not.The study of relationships between aphids’physiological indexes and relevant tea physiological indexes indicated: protein contents of aphids had significant positive correlation with tea total carbon and caffeine; fat had remarkable negative correlation with tea caffeine; AChE activities of aphids had a significant positive correlation with tea soluble sugars; CarE activities of aphids had a significant positive correlation with tea total N and soluble sugars, and a significant negative correlation with tea nitrate N; GSHs activities of aphids was non-related with tea physiological indexes detected.4. Effects of nitrogen application on ecological fitness of tea aphidsInfluences of N application on aphids’ hunger tolerance gradually improved on later generations. Aphids’hunger tolerance increased with increasing N application, but decreased at extremely high N application rates.Insecticide susceptibility to imidacloprid of G1, G2, G3 aphides as well as its bottom values lowered as N application increased, but it improved at extremely high N application rates. And susceptibility of aphids above GN improved with N application increasing. With N application increasing, insecticide susceptibility to bifenthrin G1, G2, G3 aphids decreased, but that of GN firstly decreased then improved, with a bottom value at a medium N application rate of 1.5 g/pot.Low temperature tolerance of aphids after G2 improved with N application increasing, but lowered at extremely high N application rates. G1 aphids’40℃tolerance had no significant correlation with N application, while that of G2, G3 aphids improved with N application increasing and that of aphids above GN significantly improved at medium(1.5 g/pot) and high(2.5 g/pot) N application rates. Aphids’45℃tolerance of improved with N application increasing, but lowered at extremely high rates, with peak tolerances at a N application of 1.5 g/pot.更多还原