大劣按蚊在实验条件下交配习性的观察

OBSERVATIONS ON THE MATING BEHAVIOR OF ANOPHELES DIRUS PEYTON&HARRISON,1979 UNDER LABORATORY CONDITION

我们在实验室建立了大劣按蚊自然交配种群之后,对其交配习性进行了观察。饲养初期,养蚊笼大小对其交配有一定的影响,在大蚊笼饲养交配受精率高,反之则低,饲养23代以后,两者已无明显差异。在同笼内,雌雄蚊的比例,以1:1.5者交配受精率高;1:1者低;1:2者则处于不稳定状态。大劣按蚊羽化至少在48小时后才能进行交配,随着蚊龄增长,交配受精率逐步增加,初步认为21天的蚊龄仍有交配行为存在。

Anopheles dirus is an important malaria vector.We have reported a method of rearing this mosquito in 50×50×100cm cage.Natural mating was induced by an environment simulate the natural habitat,food was improved,and a 15w blue light illumination was used for 14 hrs daily.The mating rate(i.e.fertilization rate as represented by the percentage of female mosquitoes in which sperm was found in the spermatheca)of the 28th generation reached 87.88%.In may 1983,a laboratory mating colony was at last successfully established in small cage(31×20×22cm),the mating rate of 141h generation of this colony reached 68.96%.Observations of the mating behavior of the natural mating colony were made.In the early stage of rearing the size of the cage do exert some influence on the mating of A,dirus.For example,mating rate of the 7th generation was 8%in the large cage,but only 1%in the 6th generation in small cage P<0.05.The mating rate of 14th generation could reach 68%in the large cage,but only 6%in the median cage(40×40×40cm)in the same generation P<0.01.After bred in the insectary for a long time,the mating rates between A.dims reared in cage of different size showed no obvious difference.For example,the mating rate of 24th generation was 67.31%in large cage,and that for 3 small cage of the same generation were 54.95%,62.02%and 56.89%respectively P>0.05.In 28th generation the mating rate of small cage was 80.03%and that for the large cage was 87.88%P>0.05.The influence of:ratio on the natural mating rate was studied under similiar condition.Three different proportions of:were chosen namely 1:1,1:1.5 and 1:2.Result showed that 1:1.5 was the best one giving the highest mating rate.In the small cage,the mating activity began at least 48 hours after emergence.The mating rate was 12.96%in 48-72 hours,then increased every day and might raise to 50%on the 6th day.Females bred in large cage were examined for sperm on the 4th,7th,10th,14th,18th and 21st clay of emergence.The natural mating rate increased gradually from 5.11%(4th day)to 73.11%(21st day).Thus showed that the mating activity might occur even on the 21st day of emergence.