【摘要】 <正>中华按蚊是我国传播疟疾和马来丝虫病的重要媒介,分布遍及全国各地。根据近年来国内外对它所进行的广泛研究,发现其生态习性和传病作用在各地区间差异很大,因而给防治工作带来一定的困难。为弄清产生这些现象的原因,首先必须了解种型的分化问题,但长期来的观察证明,研究复合体中的种型分化,不能停留在外部形态的观察,还应在细胞学及生化学上作更进一步的深入研究。近年来通过对多线染色体的细微研究,已能从染色体(特别是性染色体)带型的比较和对杂种染色体的分析,把冈比亚按蚊复合体中的六个种全部区别开来。同样对五斑按蚊、斯氏按蚊、流溪按蚊等若干按蚊的复合体的多线染色体观察所获得的成就,以及对某些蚊种遗传防治所取得的成功,都显示了多线染色体带型研究的应用前景。 关于中华按蚊多线染色体的研究,Sharma在印度首次报道并发表了唾腺染色体全图,日本Kanda曾发表有关中华按蚊唾腺染色体的描述,但仅见摘要,未见全文及详细的分带图。Oguma亦发表过有关文章。而此工作在我国尚处于萌芽状态。因此有许多工作亟待去做。现将我们对中华按蚊四龄幼虫唾腺染色体进行制片观察,并将唾腺染色体的组型和带型与蛹的精原细胞和卵原细胞有丝分裂中期染色体组进行比较和研究的结果报告如下。更多还原

【Abstract】 The salivary gland chromosome complement of Anopheles sinensis is composed of three pairs,which can be recognized as five arms.The sex-chromosome is the shortest one about 50-60u,in length,and is visible with one arm only.The second and the third salivary chromosomes both consist of two arms,the approximate lengths of the individual arms are: 2R,80-100u; 2L,70-90 u; 3R,100-120 u; and 3L,50-60 u.Chromosome 3 has two arms of unequal lengths,whereas in chromosome 2 the two arms are of approximately equal lengths..Although the males of this species are of heterogametic sex with one X-chromosome and one Y-chromosome,and females of homogametic sex with two X-ehromosomes,yet the salivary chromosome pictures show no detectable difference in both sexes.This suggests that the difference between X-and Y-ehromosomes probably involves their he-terochromatic regions only.It was also observed that the V-shaped sex-chromosome is shown in the salivary chromosome with one arm only,the length of which is much shorter than is expected as compared with its corresponding metaphase chromosomes,indicating that this arm of the sex-chromosome is probably composed of heterochromatin too in a fair proportion.The sex-chromosome banding of the specimen collected from the eastern suburb of Nanjing showed no observable difference from that of the specimen from the suburb of Shanghai.Under oil immersion (ca 1250x) of phase-contrast microscope about 700 bands with different degrees of shade could be observed.The characteristic 3B puff region of the sex-chromosome described here is similar to that found in the salivary gland chromosome of A.albimanus and also similar to the polytene chromosome from the ovarian nurse cell of the female adults in A.culicifades.Addenum After the completion of this article,we got a reprint of Sharma’s workon Anop.Hyr.Var.Sinensis.No photographs or specimens are available.Thus,no comparison can be made in regard to the details of the different bands.Judging from the external features,the following 3 points are noticeable:1.Sharma’s pairing is the same as ours.The ls,t pair is the shortest,in pair 2 the centromere is median,in pair 3 the centromere is subcentral.All these features meet the pairing characteristics of the various subspecies worked out by other workers.2.Sharma’s chromosomes are rather different from ours in length:3.So far as the shape of the head is concerned,1,2R,3R are somewhat similar,but the difference between 2L and 3L is rather obvious.In our specimen,the sex-chromosome has a characteristic puff which is indistinct in Indian specimen map.From the aforementioned latter 2 points we are of the opinion: The Nanjing-Shanghai specimen is somewhat different from the Indian one.更多还原