【作者】 张未仲；

【导师】 张泽华；

【作者基本信息】 中国农业科学院 ， 农业昆虫与害虫防治， 2013， 博士

【摘要】 亚洲小车蝗（Oedaleus decorus asiaticus B.Bienko）是我国北方草原重要害虫，主要分布在蒙古高原及周边地区，曾多次引发严重灾害。亚洲小车蝗主要取食禾本科植物，其营养需求趋向低氮植物。为明确亚洲小车蝗取食特性及营养需求，本研究进行了食物适应性及能量代谢相关基因研究。结果如下：通过研究不同生境植物与亚洲小车蝗种群结构的关系，测定了羊草(Leymus chinensis)、针茅(Stipa krylovii)对其生长发育指标的影响。结果表明：亚洲小车蝗种群数量与植物盖度呈负相关（R=-0.7708，p<0.01），与植物生物量呈负相关（R=-0.9052，p<0.01），蝗虫多样性（D）与植物多样性呈正相关（R=0.5884, p<0.05）；蝗虫个体总数与植物盖度呈负相关（R=-0.7593, p<0.01），与植物生物量呈负相关（R=-0.8597, p<0.01）；蝗虫混合种群更趋向生活在针茅为优势种的针茅草地类型。室内试验测定，亚洲小车蝗相同增重对羊草的消耗量大于针茅（p<0.05），对针茅的消化率高于羊草，对针茅利用效率高于羊草。本研究进行了3个生境，3个密度的亚洲小车蝗生活力指标定量分析，结果表明：针茅处理室内饲养亚洲小车蝗雄虫同羊草无明显差异、雌虫相对生长率较羊草高（P<0.05）。小区试验针茅盖度与亚洲小车蝗生活力呈指数函数关系（Y=0.355e0.0061x），拐点在盖度25%,之后生活力快速增长。羊草盖度同亚洲小车蝗生活力呈二次函数关系（Y=0.0007x2-0.00346x+0.7819）当羊草盖度小于25%时，亚洲小车蝗生活力随盖度增加而减小，当羊草盖度大于25%时，生活力随盖度增加而增长，与羊草样地相比，针茅样地中的亚洲小车蝗生活力显著升高（P<0.05）。亚洲小车蝗密度小于18头/m2时，生活力与密度正相关，密度大于18头/m2时，生活力急剧下降。植物盖度和虫口密度是影响亚洲小车蝗生活力的主要因素。本研究利用数据库中已有的基因序列，设计简并引物，扩增了亚洲小车蝗的4个基因片段（精氨酸激酶AK，反应原件结合蛋白CREB，蛋白激酶AMPK，卵黄原蛋白Vg）。其中，AK同近缘基因相似度达到95%，CREB相似度达到75%，AMPK相似度达到75%, Vg相似度41%，系统发育同源性比对结果同相似度结果一致，说明所得结果为亚洲小车蝗基因序列。用荧光定量PCR方法检测了不同样地、不同虫龄基因表达量差异。结果表明：针茅饲养的亚洲小车蝗基因表达量低于羊草饲养的蝗虫。根据基因表达量同生活力拟合相关方程：Y=0.633X22271-4.6627X1+0.0033X292-0.2685X2+210X-6.63+187.9655，X1为AK，X2为CREB，X3为AMPK。AK基因当拷贝数小于1.861016copies/μL时，生活力随着拷贝数增大而减小，当拷贝数大于1.861016时，生活力趋于平缓，AK基因表达量并没有随环境恶化而持续升高。当CREB基因拷贝数在2.211013copies/μL.到1.721015copies/μL之间时生活力持续下降，即随环境恶化而增大。当AMPK基因拷贝数在3.051012copies/μL到21013copies/μL之间时生活力持续下降，随环境恶化而增大。Vg与环境没有明显的相关性。更多还原

【Abstract】 Oedaleus decorus asiaticus B.Bienko，the major northern grassland pest, is mainly distributed inthe Mongolian Plateau and surrounding areas, whose repeated outbreaks has caused serious disasters..O.asiaticus mainly feeding on grasses, and their nutritional needs incline to low-nitrogen plants. Inorder to clarify the feeding characteristics and nutritional needs of O.asiaticus, this study examines thefood adaptability and genes of energy metabolism. Results are as follows：This study examined the relationship between plants and O.asiaticus population structure in thedifferent habitats, and assayed effect of Leymus chinensis, S. krylovii (Stipa krylovii) on growth anddevelopment. The results indicate that the amount of O.asiaticus is negatively correlated with thecoverage of plant (r=-0.7708，P<0.01), and the biomass of plant (r=-0.9052, P<0.01).The diversity ofgrasshopper is positively correlated with the diversity of plant (r=0.5884, P<0.05). The amount of thegrasshopper is negatively correlated with the coverage of plant (r=-0.7593, P<0.01) and the biomassof plant (r=-0.8597, P<0.01). The consumption of O.asiaticus indoor is Leymus chinensis> Stipakrylovii (P<0.05). S. krylovii efficiency is higher than L. chinensis.By applying both the fields net and indoor independent feeding method, this study compared thevitality index of three groups of O.asiaticus with3population densities, and quantitatively analyzed theeffect of S.krylovii and L. chinensis on the growth and development of O.asiaticus.The result indicatsthat the relative growth rate of female, which feed on S.krylovii, is higher than those feed on L.chinensis (p<0.05). The relationship between the coverage of S.krylovii and the vitality value fits theexponent function (Y=0.355e0.0061x). When the coverage of S.krylovii is less than25%, the vitalityvalue increased slowly with the increase of the coverage. When the coverage is more than25%, thevitality value increased rapidly. The relationship between the coverage of L. chinensis and the vitalityvalue fits quadratic function (Y=0.0007x2-0.0346x+0.7819). When the coverage of L. chinensis is lessthan25%, the vitality value decreased with the increase of coverage. When the coverage is more than25%, the vitality value is positively related with the coverage. The vitality of O.asiaticus in S.kryloviiis better than in L. chinensis. The plant coverage and the population density are main factors to affectthe vitality of O.asiaticus.On the basis of gene sequence of the database, we design degenerate primer to amplicationO.asiaticus of4genes (AK, CREB, AMPK, Vg). affinis similarity is AK95%, CREB75%, AMPK75%, Vg41%. Homology of O.asiaticus is accordant with similarity, which indicated the genesequence is exist in O.asiaticus. We detected gene expression of different instar in different plots byquantitative PCR. The result showed that, the gene expression of O.asiaticus fed on S.krylovii ishigher than which fed on L. chinensis. On the base of gene expression and vitality value, the matchequation of correlationY=0.633X2-6.62271-4.6627X1+0.0033X22-0.2685X2+2E+09X3+187.9655, X1is AK, X2is CREB, X3isAMPK. When the gene copy number of AK is less than1.86×1016copies/μL, the vitality value decreased with the increase of the copy number. When the gene copy number is more than1.86×1016,the vitality value decreased slowly with the increase of copy number. The expression of AK is notcontinue to rise with environmental degradation. When the copy number of CREB is between2.21×1013copies/μL and1.72×1015copies/μL, the vitality value decreased with the increase of copynumber. When the copy number of AMPK is bwtween3.05×1012copies/μL and2×1013copies/μL, thevitality value decreased with the increase of copy number. The gene expression of CREB and AMPKcontinue to rise with environmental degradation, the gene expression of Vg is not obvious correlationwith environment.更多还原