中国特有果蝇 Drosophila curviceps 种亚组在Drosophila immigrans种组中的种系发生地位

果蝇immigrans种组中的curviceps种亚组是1992年新建立的中国特有果蝇类群。该种亚组中的物种主要分布在中国大陆和台湾。目前除了形态学水平的研究外,还没有其他证据支持建立该种亚组的合理性及其起源和种系发生地位。为了在DNA分子水平上探讨果蝇curviceps种亚组在果蝇immigrans种组中的种系发生地位,从而为今后更深入地研究中国特有果蝇,甚至为果蝇亚属的进化遗传学提供理论依据,测定了immigrans种组5个种亚组（nasuta、immigrans、hypocausta、quadrilineata、curviceps)中12个代表物种的rDNA的ITS1和部分Adh基因的序列。其中ITS1序列的长度为513－587bp,共有191个信息位点;Adh基因片段的长度在714－747bp之间,共99个信息位点。考虑到单个分子提供的信息较少,将两个分子的序列综合起来,组成一个较长的复合序列。分别根据ITS1,Adh和两个分子的复合序列排比（Alignment)结果,和最大简约法和邻接法构建分子系统树,其中根据复合序列构建的系统树与形态学研究结果最为一致。分子树显示curviceps种亚组的特种确定单独形成一个分枝,为种亚组级的分类阶元,支持了形态学将其建立为一个新种亚组。根据Kimura距离,估算了复合分子的替换速率约为每百万年1．48％,进而计算出5个种亚组的分 歧年代。结合各物种的地理分布,推测了immigrans种组的进化历史：curviceps种亚组与quadrilineata种亚组的亲缘关系最近,主要分布在中国南部的温带地区。它们之间的分歧时间大约为3．4百万年,是最年轻的两个种亚组。主要分布在苏门答腊及附近的热带地区的hypocausta种亚组的物种是最早分化出来的,与其他种亚组的分歧时间约为9．2百万年。该结果与形态学和生物地理学研究相吻合。值得一提是的,目前归属仍存在争议的物种D.neohypocausta,在分子系统树中与hypocausta种亚组的物种相距较远,而与immiagrasn种亚组的关系较近,但分枝置信度较低（＜50％）。由于还缺乏其他方面的证据,因此D.neohypocausta的归属有待今后的研究来作定论。     

Mitochondrial polymorphism shapes intrapopulation behavioural variation in wild Drosophila

Intrapopulation variation in behaviour, including activity, boldness and aggressiveness, is becoming more widely recognized and is hypothesized to substantially affect ecological and evolutionary dynamics. Although previous studies used candidate-gene approaches and genome-wide association analyses to identify genes correlated with variations in activity and aggressiveness, behavioural variation may not be fully captured in the nuclear genome, as it does not account for mitochondrial genomes. Mitochondrial genes encode products that are key regulators of the cellular energy-producing pathways in metabolic processes and are thought to play a significant role in life-history and reproductive traits. In this study, we considered many isofemale lines of Drosophila immigrans established from two wild populations to investigate whether intrapopulation variation in the mitochondrial genome affected activity level within this species. We identified two major haplogroups in these populations, and activity levels in both larvae and adults differed significantly between the two haplogroups. This result indicated that intrapopulation variation in activity level may be partially controlled by mitochondrial genes, along with the interaction between nuclear and mitochondrial genes and the age of individual organisms.     

伊米果蝇种组（Drosophila immigrans species group）H2a-H2b和Cyt b分子系统发育关系（简报）

伊米果蝇种组(Drosophila immigrans speciesgroup)是果蝇科(Drosophilidae)、果蝇属(Drosophi-la)、果蝇亚属(Drosophila)中数量最多的一个类群,主要分布于东洋区。在分类学上该种组分为nasuta、immigrans、hypocausta、quadrilineata和curviceps五个种亚组(species subgroup)[1],东洋区果蝇区系中伊米果蝇种组中包括94个种,其中有45个种分布在中国[2]。而且curviceps种亚组是1992年新建立的中国特有果蝇类群[3]。迄今,对伊米果蝇种组分子系统关系的报道还很少,有些物种的归属仍存在争议。伊米果蝇种组还有些问题需要探讨[4]。组蛋白基因…     

Chromosomal Polymorphism in Korean Natural Populations of Drosophila immigrans

ABSTRACT To analyze chromosome inversions of Drosophila immigrans , wild flies were captured from large vineyards located in the suburbs of Yecheon and Gyeongsan from October 1999 to 2001. With the egg samples obtained singly at each of the 799 females of D. immigrans , cytological examinations were carried out for the type and frequency of inversions. Two types of different inversions were found only in the second chromosome. The inversions detected were known to be the cosmopolitan inversion "A" and "B". The mean frequency of inversion A was estimated to be 0.074 in Yecheon and 0.066 in Gyeongsan and that of B was to be 0.026 in Yecheon and 0.021 in Gyeongsan, respectively. In the frequency ratio, inversion A was significantly higher than that of B. The present populations of D. immigrans showed subtle differences from other Korean populations in inversion frequencies. To account for the local variations observed in inversion frequencies, several hypotheses are discussed such as founding event or selective force.     

The effect of travel time on oviposition behavior and spatial egg aggregation: experiments with Drosophila

A higher degree of spatial egg aggregation is often observed in environments where resource patches are more sparsely distributed. This suggests a higher probability of species coexistence when resource distribution is sparse. However, it is still unclear how the degree of spatial egg aggregation increases. I propose a model to explain this phenomenon, which assumes that (i) egg load (the number of mature eggs in ovaries) increases in the travel period between resource patches and (ii) the retention of eggs in the ovaries is harmful (egg load pressure). With these assumptions, a female would lay accumulated eggs on arrival at a new resource patch, resulting in a higher degree of spatial egg aggregation. Laboratory experiments with three drosophilid species, Drosophila simulans Surtevant, Drosophila auraria Peng, and Drosophila immigrans Sturtevant, support the model. This study provides evidence that host availability affects the spatial egg aggregation via egg load.     

中国春小麦株高、育性近等基因系的建立及应用

以矮败小麦和中国春小麦为材料,经过杂交和连续回交,得到了中国春小麦遗传背景的分别表现矮秆不育、矮秆可育、高秆不育、高秆可育的近等基因系。根据近等基因系各成员系的株高表现,计算出矮秆基因Rht10的降秆强度是69.8%。借助于赤霉酸处理,在幼芽期就可分出矮败中国春小麦后代的不育株与可育株。 Abstract：　Use Dwarfing Male-sterile Wheat and cv. Chinese Spring as parents, after cross and continuously back cross, the isogenic lines with Chinese Spring background were developed. These lines include dwarfing male-sterile line, dwarfing fertile line, tall male-sterile line and tall fertile line. The dwarfing intensity of gene Rht10 was calculated to be 69.8% according the differences between the isogenic lines. Treated with GA3solution, the male-sterile and fertile plants in Chinese Spring Dwarfing Male-sterile Wheat can be identified clearly when they are seedlings.     

中国大陆部分地区Drosophila immigrans果蝇种群中mtDNA的遗传多态性研究

选用14种限制性内切酶对分布在中国大陆部分地区的Drosophilaimmigrans果蝇种群的线粒体DNA（mtDNA）限制性片段长度多态性（RFLP）进行了分析。在6个地理种群的46个单雌系中仅检测到11种限制性类型。表征种群内均一程度的I值平均为0．833。衡量种群间等同程度的J值平均为0．797。在整个种群中只有16．8％（Gst）的变异是由种群间变异所引起的。说明分布在中国大陆部分地区的D．immigrans果蝇的遗传组成均一程度高,遗传多态程度低,遗传变异贫乏。由UPG法分析6个种群的净遗传距离,显示了分布在秦岭华阳种群（HY）的特殊性。推测D．immigrans果蝇扩散到云南的高海拔地区可能是较晚发生的事件。并推测中国大陆的D．immigrans种群比分布在中国台湾,日本的种群原始。     

Search strategies of fruit flies in steady and shifting winds in the absence of food odours

Abstract. Flight behaviour by females of two species of fruit flies, Drosophila funebris and Drosophila immigrans , was videorecorded in a wind tunnel in still air and in wind with a constant or shifting direction. Flies which were deprived of food overnight took flight in the absence of food odours. Both species responded to the presented winds in agreement with two models that predict the shortest distance to an odour plume. According to these models, the shortest distance to an odour plume is travelled when insects fly at right angles to the wind with a steady direction. In winds shifting over more than 60, the shortest distance to an odour plume is achieved when insects fly parallel to the time-averaged wind direction. We propose a behavioural mechanism which accomplishes the observed flight directions taken by the two species of fruit flies in response to the tested wind regimes.     

Fitness consequences of body melanization in Drosophila immigrans from montane habitats

We investigated eight populations of Drosophila immigrans from low to high montane localities (600–2202 m) for altitudinal variations in abdominal melanization and fitness-related traits (desiccation resistance, copulation duration, and fecundity). On the basis of common garden experiments, persistence between-population differences at 21°C suggests that observed variations in fitness-related traits have a genetic basis. Parent–offspring regression analyses showed higher heritability (h²= 0.77) for melanization patterns on all the abdominal tergites. All the traits showed significantly higher repeatability across generations. Under colder and drier environments in dispersed montane localities, abdominal melanization and desiccation resistance significantly increased (1.5–1.9 fold) along altitude. Thus, there are correlated effects of abdominal melanization on desiccation resistance. Genetic correlations, based on family means, were significantly high between abdominal melanization and other fitness traits. Furthermore, darker flies along increasing altitude resulted in a 35–40% increase in copulation duration as well as fecundity. There are significantly positive correlations of abdominal melanization with copulation duration as well as fecundity on the basis of within- as well as between-population variations. Such observations are in agreement with the thermal budget hypothesis. Present data suggest that changes in body melanization impact fitness-related traits in montane populations of Drosophila immigrans .