【作者】 蔡英；

【导师】 贺虹；

【作者基本信息】 西北农林科技大学 ， 森林保护学， 2011， 硕士

【摘要】 食锈菌瘿蚊Mycodiplosis sp.隶属双翅目Diptera瘿蚊科Cecidomyiidae,是取食松杨栅锈菌Melampsora larici-populina Kleb.夏孢子堆的天敌昆虫,对于控制该种病原菌的流行发生具有潜在的利用价值。本文通过田间调查及室内饲养相结合的方法,研究了食锈菌瘿蚊Mycodiplosis sp.各虫态的外部形态特征、生物学特性、幼虫空间分布型及温度对蛹生长发育和成虫寿命的影响,研究结果对于进一步深入研究该种天敌昆虫的生态学、行为学、遗传学以及生物防治上的利用等具有重要的意义。主要取得的研究结果如下:1.食锈菌瘿蚊Mycodiplosis sp.外部形态特征研究(1)卵:卵长椭圆形,几粒聚产在一起,长0.2-0.3 mm,宽0.09-0.1 mm,表面光滑,通体透明,背侧稍隆起呈弧形,腹侧平直。(2)幼虫:虫体纺锤形,头缩入前胸内,无足,整个体表被鱼鳞状骨化片突起,其大小与疏密度因虫体部位而异;前胸、中胸和后胸为平滑的膜状,胸部腹面具有特殊的“M”形纹,腹部腹面每节前缘具有排列成椭圆形的骨片群,骨片尖长,长短不一,齿尖向后,具有腹足的功能;体表共有四种感受器:锥形Sensillum basiconicum、腔锥形Sensillum coeleoconica、钟形Sensillum campaniform以及位于腹部两侧的伞状感受器,其中伞形感受器还未见在其他昆虫体表结构研究中有报道,其具体功能未知。(3)蛹:蛹为离蛹,蛹体由淡黄色变为赤褐色,其发育可分为前期、初期、中期、后期四个阶段。蛹的每个体节都具有均匀分布、向后生长的锯齿状骨片;蛹头部分别着生有一对触角和感觉毛。(4)成虫:雌成虫体长约1.25-1.5 mm,雄成虫体长约0.9-1.1 mm,密被绒毛。触角细长,念珠状2+12节,雄虫触角长于雌虫,触角上着生有四种毛状感受器:短绒毛感受器Sensillum micro-villus、钩状毛感受器Sensillum uncinus、环状毛感受器Sensillum circumfila、藤状毛感受器Sensillum rattan-like。2.食锈菌瘿蚊Mycodiplosis sp.生物学特性研究食锈菌瘿蚊在陕西周至地区一年可完成多代,具有明显的世代重叠现象,以老熟幼虫在土壤中越冬。翌年4月越冬代成虫开始羽化出土,一直到6月结束,5月中旬为羽化盛期。幼虫盛期为8月中旬至9月下旬,与叶锈菌的发生形成紧密的物候关系,11月中旬基本全部入土越冬。食锈菌瘿蚊Mycodiplosis sp.一天中有两个羽化高峰期,分别为上午07:00-09:00和下午17:00-19:00,成虫寿命较短,一般2-3天。老熟幼虫一天中有两个化蛹高峰期,分别为上午09:00-11:00和下午15:00-17:00。3.温度对食锈菌瘿蚊Mycodiplosis sp.蛹发育及成虫寿命的影响在智能人工气候箱内5个恒温条件下(18℃、22℃、26℃、30℃和34℃)测定了食锈菌瘿蚊蛹的发育历期和成虫寿命,对其蛹的发育起点温度和有效积温进行了研究。结果表明:在18℃～30℃的温度范围内,蛹的发育历期和成虫寿命从18℃的11.23d和5.58d缩短至30℃条件下的5.98d和2.98d,表现为蛹发育历期和成虫寿命与温度呈负相关,且温度对食锈菌瘿蚊蛹的发育历期和成虫寿命具有显著影响(p<0.05);当温度达到34℃时,发育历期略有延长,发育速率减缓;蛹的发育起点温度为5.82±2.28℃,有效积温为142.03±17.52日/度。4.食锈菌瘿蚊Mycodiplosis sp.幼虫空间分布型食锈菌瘿蚊Mycodiplosis sp.幼虫的空间分布型研究结果表明:食锈菌瘿蚊Mycodiplosis sp.幼虫在林间呈聚集分布;其幼虫幼虫聚集均数指标λ>2,分析其幼虫聚集分布原因可能是由于环境异质性,昆虫本身的产卵习性、聚集行为,或者是两种因素共同作用的结果;同时利用Iwao回归确定了最适理论抽样模型N=1/D2(3.86/m+0.73)。更多还原

【Abstract】 Mycodiplosis sp. belongs to Cecidomyiidae of Diptera. It is an enemy insect which feeds on the uredium of poplar leaf rust Melampsora larici-populina Kleb., so it has a potential value for controlling the pathogen prevalence. In this paper we studied the morphology, biological characteristics, larvae spatial distribution pattern, the effect of temperature on pupae development period and adult longevity of Mycodiplosis sp. using field investigation and lab breeding, and the research results will play an important role to further study the ecology, behavior, genetic and utility for biological control of Mycodiplosis sp..1. Morphological characteristics of Mycodiplosis sp.(1) Egg: Egg is oval, the length is 0.2-0.3 mm and width is 0.09-0.1 mm, the surface of egg is smooth and transparent. Egg dorsal is slightly uplift like arc, and ventral is straight.(2) Larva: Apodous larvae are fusiform, and the head retracted into prothorax. The results after scanning the larval body surface showed that it was very special and covered with the ossification slice like fish scale, the size and density of them is different in different parts of larval body. The prothorax, mesothorax and metathorax are all smooth film, there was one special“M”shape in prothorax venter. Serrated ossification slice of abdomen venter were sharp, long and backward, instead of pleopod. Four types of sensillums were found on the larval body surface, they are Sensillum baisconicum, Sensillum coeleoconica, Sensillum campaniform, and special Sensillum umbrella-shape located at the both sides of abdomen separately. The Sensillum umbrella-shape has not reported in other insects and its function was unknown.(3) Pupa: The pupa is exarate pupa, and the body color changed from pale yellow to russet, it has distinguished into four developmental stages such as prepupa, initial stage pupa, medium stage pupa and late stage pupa. Each segment has serrated ossification slice that evenly and backward, there is a pair of antennae and sensillum located at pupa head.(4) Adult: The length of female adults are about 1.25-1.5 mm, male adults are about 0.9-1.1 mm, and all of them covered with with densely tomentum. The moniliform antenna has 2+12 sections. Four types of sensillums were found on the antenna, and they are Sensillum micro-villus, Sensillum uncinus, Sensillum circumfila and Sensillum rattan-like. 2. Biological characteristics of Mycodiplosis sp.Mycodiplosis sp. can occur several generations one year, and has generation overlapping. It overwinters with last instar larvae in soil. Adults emergence from the soil in Apirl of next year and can last until June, the peak of emergence period is in the middle of May. The peak time of larvae is from mid August to late September, has a close phenology connection with the occurence of Melampsora larici-populina Kleb.. In mid November almost all larvae go into soil for overwintering. The adults have two peak emergence period such as 07:00-09:00 and 17:00-19:00 each day, adults can live about 2-3 days, while the last instar larva also have two peak pupation of 09:00-11:00 and 15:00-17:00.3. Temperature effect for pupae developmental and adults lifeThe developing period of pupae and adults life of Mycodiplosis sp. were studied under the five constant temperature (18℃, 22℃, 26℃, 30℃, 34℃) , analyzing the developmental threshold temperature and effective accumulative temperature of pupae. The results showed that the development period of pupae and adults life was reduced from 11.23d and 5.58d in 18℃to 5.98d and 2.98d in 30℃, and was negatively related with temperature, while the temperature had a significant influence on the developing period of its pupae and adults life(P<0.05). The development period of pupae and adults it extended a few and the developing speed became slow in 34℃. The developmental threshold temperature of pupae was 5.82±2.28℃, and the effective accumulative temperature was 142.03±17.52 day/degree.4. Space distribution of the larvaeThe larvae spatial distrbution pattern of Mycodiplosis sp. showed that Mycodiplosis sp. larvae had an aggregated distribution, this may be due to environmental heterogeneity, innate spawning behavior and aggregated behavior. A theoretical sampling model was developed by Iwao regression is N=1/D2(3.86/m+0.73).更多还原