恙虫病主要媒介地里纤恙螨红、白体色的杂交试验

Experimental Hybridization of Red and White Leptotrombidium Deliense (Acarina: Trombiculidae)

本文报道在实验室内培育的地里纤恙螨种群中出现的极少量白体色突变株杂交后代体色、雌雄比例与生殖能力的观察和测定结果。白体色突变株的第6号染色体已出现显著的差异。白体色突变株连续培育3代体色仍为白色。红、白配对正交、反交与红、白群体杂交培育的1～3代的个体均呈红色,并显示杂交后其生殖能力有显著提高。

1. In the larval population of Leptotrombidium deliense(orange-red colour with brilliant red eyespots) appeared a few white larvae after several generations of pure line breeding in the laboratory. The chromosome number of both red and white individuals are the same (2n = 14) , but the relative length of chromosome no. 6, markedly different (P = 4×10-4), as well as the real length of chtomosomes no. 6 and no. 7. It seems that the white individuals might be the mutants.2.Hybrids of red F2 and white F2 gave rise to more male than frmale. The sex ratio being 2 to 1 or 3 to 1, instead of 1 to 1 in normal.3. As compared with the normal strains, hybridization caused obviously the increasing of reproductive ability to approximate four times over that of the normal.