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11.
目的分析家蚕近交系IS-c108A的遗传纯度,为家蚕实验动物化的培育工作提供指导。方法应用经过筛选的20条随机引物对家蚕近交系IS-c108A(F10)的3个蛾区各30个个体和该近交系的亲本系统c108、对照实用化品种871各30个个体的基因组DNA进行RAPD扩增,计算个体间和蛾区间的相似系数及遗传距离。结果家蚕近交系IS-c108A(F10)的3个蛾区内的多态性带频率分别为1.807%、1.841%、1.841%,平均为1.830%;起点亲本c108个体间多态性带频率为7.207%,对照品种871个体间的多态性带频率为7.08%;而近交系IS-c108A与c108之间的多态性带频率为49.20%,c108和871品种之间的多态性带频率为58.33%。家蚕近交系IS-c108A10的3个蛾区内个体之间遗传相似系数的平均值分别为0.99581、0.99555、0.99551,总平均为0.99562。结论家蚕近交系IS-c108A(F10)已具有较高的遗传纯合度,家蚕具有易于获得高纯的有利条件。  相似文献   
12.
A quick and inexpensive method to determine absolute nannofossil abundance in deep sea sediments – the “drop” technique (modified dilution method) – was compared to two other available methods – the filtration and random settling techniques. All techniques rely on the same basic principle, under which a volume of known concentration (bulk sediment weight/mL) is distributed evenly over a known total area (glass slide or filter) to then count particles within a set of (randomly) selected fields of view. The three preparation techniques were also calibrated by spiking the samples with microbeads to approach the “real values” as closely as possible. Significant offsets in abundance estimates between methods mainly reflect bias due to the uneven distribution and/or loss of particles. We show that the drop technique is most consistent and accurate in estimating “real values” and offers similar or better reproducibility than the other techniques. The drop method also allows detection of the same trends with or without calibration with microbeads. The filtration method holds the risk to drastically underestimate absolute abundances, while the settling technique is demanding in terms of time and may suffer from advection processes. The composition of nannofossil assemblages can be reliably determined by any of the three different techniques.  相似文献   
13.
Queensland fruit fly [Bactrocera tryoni (Froggatt), Diptera, Tephritidae] is the most devastating insect pest impacting Australian horticulture. The Sterile Insect Technique (SIT) is an important component of tephritid pest management programs. However, mass‐rearing and irradiation (to render insects sterile) may reduce the fitness and performance of the insect, including the ability of sterile males to successfully compete for wild females. Manipulation of the gut microbiome, including the supplementation with bacterial probiotics shows promise for enhancing the quality of mass‐reared sterile flies, however there are fewer published studies targeting the larval stage. In this study, we supplemented the larval stage of mass‐reared B. tryoni with bacterial probiotics. We tested several individual bacteria that had been previously isolated and characterized from the gut of wild B. tryoni larvae including Asaia sp., Enterobacter sp., Lactobacillus sp., Leuconostoc sp. We also tested a consortium of all four of these bacterial isolates. The fitness parameters tested included adult survival in field cages, laboratory mate selection of bacteria supplemented males by bacteria nonsupplemented females, and laboratory locomotor activity of adult flies. None of the bacterial probiotic treatments in the current study was significantly different to the control for field survival, mate selection or locomotor activity of adult B. tryoni, which agree with some of the other studies regarding bacterial probiotics fed to the larval stage of tephritids. Future work is needed to determine if feeding the same, and/or other probiotics to adults, as opposed to larvae can positively impact survival, mating performance, mating competitiveness and locomotor activity of B. tryoni. The bacterial group(s) and function of bacterial species that increase fitness and competitiveness is also of interest to tephritid mass‐rearing programs.  相似文献   
14.
Area-wide Sterile Insect Technique (SIT) programmes against medfly, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), are being increasingly implemented worldwide. A key issue for SIT is to release sterile males that are sufficiently competitive with males from the wild population. Post-teneral nutrition and ginger root oil (GRO) exposure of sterile males prior to release have been shown to improve male competitiveness or performance. However, few studies are available on the effect of post-teneral nutrition and ginger oil exposure on longevity and mortality in bait treatments by sterile male C. capitata . In this study, we found that longevity was increased by the addition of protein to the standard pre-release sugar diet, whereas exposure to GRO did not influence the longevity of sterile males. Mortality in spinosad baits was influenced both by diet and GRO exposure. Sterile males on a protein-deprived diet suffered greater mortality than sterile males fed with both sugar and protein. When sterile males were fed on the protein-deprived diet, GRO exposure increased their mortality. However, no significant differences were found in adults on the sugar-protein diet, whether or not they had been exposed to GRO. These results show, for the first time, a negative effect of GRO exposure in terms of increasing mortality in proteinaceous bait treatments, a common practice in areas where SIT is implemented. Nevertheless, this effect could be reduced by the addition of protein to the standard pre-release diet. The implications of these results for SIT programmes against C. capitata are discussed.  相似文献   
15.
A new method for obtaining dermatoglyphic prints is described. Photographic film is used enabling prints to be obtained directly, and at any enlargement. The sweat-pores can be shown in detail, and counted.  相似文献   
16.
The plant-to-plant movement of aphids was investigated by the simulation technique in this report. Trials satisfying the following conditions are repeated and the results are compared withShiyomi 's model (1967).
  1. An arbitrary individual moves at any moment.
  2. The individual moves straightly forward an arbitrary direction and climbs up the plant that he first encounters with.
  3. There is no concentrative birth and death.
Some of the results are as follows:
  1. For an ideal state of movement, an equation describing the relationship between the frequency of actual movement and the degree of changes in the spatial distribution by movement was obtained.
  2. The actual movements, whose frequency we cannot count, changes the spatial distribution of insects, and this change can be evaluated by the changes of values of the parameters contained inShiyomi 's model. Using the statement (i), we can also estimate the frequency of movements of aphids in the ideal (extreme) state.
  相似文献   
17.
蚂蚁是分布广泛、种类和数量丰富的社会性昆虫.蚂蚁的传统分类学研究存在一定局限性,而分子生物学为蚂蚁的系统学研究提供了新途径.概述了蚂蚁分子系统学在研究内容和技术方法上的研究进展,并对今后的研究做了展望.  相似文献   
18.
A modified Segmental Sedimentation and Counting Technique (SSCT) to examine the presence of Echinococcus multilocularis helminths in segments of fox (Vulpes vulpes) intestine is described and compared to the “gold standard”, SCT. Out of the 358 intestines collected, 117 were E. multilocularis positive. Using SSCT methods we compare the sensitivity of individual or pairs of segments to establish a tradeoff between saving time and the reliability of the diagnosis, especially in areas with low infection intensities. The results show that the analysis of segment S4 associated with segment S1 or S2 give 98.3% sensitivity, with specificity close to 100%. Based on our results and the time saved, we recommend using SSCT for routine examination of fox intestines for large epidemiological studies, particularly where the endemic prevalence of E. multilocularis is low or unknown.  相似文献   
19.
刘二曼  印莉 《植物研究》1998,18(1):90-96
应用韭菜微核技术,检测哈尔滨市量具刃具厂含铬废水的遗传毒性,试验表明:含铬废水可诱导韭菜和蚕豆根尖细胞产生微核,进行回归分析,其蚕豆对Cr^+6诱变剂回归分析为y=24.94+127.77x(r=0.996,P〈0.01),韭菜对Cr^+6诱变剂回归广泛为:y=21.74+100.23x(r=0.900,P〈0.01),r=11.17+3.38x(r=0.781,P〈0.05),韭菜根尖微核技术具  相似文献   
20.
虎纹捕鸟蛛的饲养与繁殖技术   总被引:12,自引:0,他引:12  
本文简要介绍饲养、繁殖虎纹捕鸟蛛的技术,包括它的形态特征、生活习性、食物种类及饲养器具等,并介绍了在饲养和繁殖中应注意的一些问题。  相似文献   
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