0000000000241788
AUTHOR
H. Laven
Meiosis in translocation heterozygotes in the mosquito Culex pipiens.
Adult Culex pipiens males irradiated with both X-rays and neutrons were crossed to untreated females and F1-egg rafts were checked for dominant lethality. F1-progenies were outcrossed with normal individuals in order to obtain lines with inherited semisterility. From a total of 120 lines that showed a certain amount of sterility 12 lines were studied cytologically. 10 lines showed reciprocal chromosome exchanges.—At late pachytene and diplotene cross configurations with large asynaptic regions at the center of the cross are obligatory. Bivalents, chains of three, chains of four, and ring configurations are present at metaphase and anaphase I. The different frequencies of the occurrence of s…
Génétique formelle, lutte génétique et structures des populations de Moustiques
La genetique formelle des insectes vecteurs ou nuisibles en est en general encore a ses premiers pas. Un resume des connaissances sur cette question a ete publie recemment dans le livre « Genetics of Insect Vectors of Disease ». Si on la compare a celle des insectes comme Drosophila , on se rend compte a quel point la genetique des insectes nuisibles est peu connue malgre leur importance. Le peu que l’on sait a ce sujet sur les especes les mieux etudiees comme Aedes aegypti ou Culex pipiens demontre cependant qu’il est possible d’etudier la genetique formelle qui servira de base necessaire a des etudes plus elaborees, particulierement dans le cadre du developpement et de l’evaluation des me…
Development of cytoplasmically incompatible and integrated (translocated incompatible) strains ofCulex pipiens fatigans for use in genetic control
Crosses were made between strains of the Culex pipiens complex to select and develop strains with suitable cytoplasmic incompatibility properties for use in field experiments in genetic control of Culex pipiens fatigans near Delhi, India.
Eradicating Mosquitoes using Translocations: a First Field Experiment
THEORETICAL considerations have led to the assumption that chromosomal translocations with ensuing semisterility could be used to control pests1–3. Inversions could have the same effect in animals and plants in which crossing over occurs in both sexes4. Many translocations of different type and with various degrees of sterility have been produced in the mosquito Culex pipiens5–8. Preliminary laboratory experiments with these translocations have shown that a cage population can be diminished and finally exterminated after a few generations by the release of translocation heterozygotes into the population9.
Möglichkeiten der genetischen Schädlingsbekämpfung1
Possibilities of controlling insects by genetical methods. Up to this time only a few practical experiences are made in controlling insect pests by help of genetical methods. The differences between this method and the sterile male technique are shown and seven ways of genetic control are discussed.
Inherited semisterility for control of harmful insects. II. Degree of sterility and types of translocations in the mosquito Culex pipiens L.
Fur die Anwendung von Semisterilitat infolge von Translokationen zur Bekampfung schadlicher Insekten ist der Grad der Semisterilitat und die Art der zugrundeliegenden Translokation von Bedeutung. Von den bisher untersuchten 124 Translokationen hatten 101 einen Sterilitatsgrad zwischen 10 und 50%, 23 uber 50 bis zu 85%. Mit dem mannlichen Geschlechtsfaktor M gekoppelte Translokationen sind zur Zeit die fur die Praxis am nutzlichsten. Sie treten nicht so haufig auf als erwartet, machen aber doch rund 1/4 aller getesteten Translokationen aus. Es werden Grunde angefuhrt, weshalb M-gekoppelte Translokationen nutzlicher sind.
Eradication of Culex pipiens fatigans through Cytoplasmic Incompatibility
Culex pipiens fatigans is the chief vector of filariasis in south-east Asia. Urbanization has often caused the numbers of this mosquito—and with it the danger of filariasis infection—to increase alarmingly1. The natural vigour, tolerance and fast development of resistance to insecticides of this mosquito necessitate the development of other control methods, and cytoplasmic incompatibility2 seems to be an ideal means.
Inherited semisterility for control of harmful insects. III. A first field experiment
Fortlaufende Freilassung von semisterilen Mannchen in eine isolierte Freilandpopulation vonCulex pipiens fuhrte zu einer Verminderung dieser Population auf 10% der maximalen Populationsgrosse.
Eradicating Mosquitoes using Translocations
CHROMOSOMAL translocations have been suggested1,2 as useful mechanisms for genetic control: translocation heterozygotes produce fewer offspring because some of their gametes do not receive a full chromosomal complement. The resultant semisterility has been observed in many plants and animals, chiefly after irradiation or other treatments of laboratory stocks but only rarely in natural populations. Spontaneous translocations originating in a field population are usually eliminated3 quickly because of the lower productivity they confer on the heterozygotes. They can become fixed in all members of a population only if it is small and isolated4.
Une expérience de lutte génétique contre Culex pipiens fatigans Wied., 1828
Le croisement entre les membres de populations allopatriques du complexe de Culex pipiens peut donner lieu a quatre resultats differents. La majorite des populations produit une descendance normale dans les croisements reciproques alors que certains autres donnent des descendants dans une direction et que les embryons n’eclosent pas dans la direction opposee. D’autres croisements sont infeconds dans les deux directions. Cette absence de descendance est due a une incompatibilite cytoplasmique qui est cytoplasmique- ment hereditaire. Elle demeure constante dans la lignee femelle pendant un nombre indefini de generations. Le spermatozoide est bloque dans un croisement incompatible avant qu’il …
Inherited semisterility for control of harmful insects. I. Productions of semisterility due to translocation in the mosquito,Culex pipiens L., by X-rays
In Anbetracht der theoretischen und in einem Freilandexperiment bereits erwiesenen Moglichkeit der Bekampfung von Schadinsekten durch Freilassung semisteriler Tiere wurde die Produktion von Translokationen und damit verbundener Semisterilitat bei der StechmuckeCulex pipiens untersucht. Die Totalrate der erzeugten Translokationen liegt bei Stechmucken im Vergleich zuDrosophila auffallend hoch. Es besteht offenbar eine Korrelation zwischen der Gesamtlange der Chromosomen und der Translokationsrate.