裸仁美洲南瓜种皮性状遗传规律研究

采用3个有壳美洲南瓜自交系04FC409-4、03N-122-19、04LAg-26-2和3个无壳美洲南瓜自交系04GD112-7、1N-275-7、04LAg-26-28作亲本,通过正、反交及回交组配,对其杂交组合(04FC409-4×04GD112-7、03N-122-19×1N-275-7、04LAg-26-2×04LAg-26-28)的F₁、F₂、BC₁和BC₂各世代的种皮分离比率进行统计分析,结果表明,F₁代种皮性状表现一致,无论正、反交均表现为有壳;F₂代无论正、反交都分离出有壳和无壳2种性状,且分离比率接近3∶1;BC₁(以有壳的自交系作父本进行回交)种皮均表现为有壳,BC₂(以无壳的自交系作父本进行回交)种皮则表现出有壳和无壳的分离,分离比率接近1∶1。根据经典遗传学原理对种皮的遗传效应进行了研究,初步推断出:美洲南瓜种皮的有壳与无壳受一对核基因控制,有壳对无壳为显性。

A study on the genetic law of seed coat characters in hull-less Cucurbita pepo

The seed coat trait of Cucurbita pepo was classified into two types,seed-hulled and seed-naked.Experiments were performed to study the inheritance pattern.Three inbreeds with hulled seed,04FC409-4,03N-122-19 and 04LAg-26-2,and three inbreeds with hull-less seed,04GD112-7,1N-275-7 and 04LAg-26-28,were used as the parental lines in the mating patterns 04FC409-4 and 04GD112-7,03N-122-19 and 1N-275-7,04LAg-26-2 and 04LAg-26-28.In the F1 generations,all the plants were seed-hulled.However,in the F2 generations,segregation of hulled and hull-less seeds showed the ratio of almost 3 to 1.For the backcrosses,all the BC1 and F1(the inbreed with hulled seed used as recurrent parent) generations appeared seed-hulled.But in the BC2 and F1(the inbreed with hull-less seed as recurrent parent) generations,segregation of hulled and hull-less seeds showed the ratio of almost 1 to 1.So it was concluded that each of the hulled seed and hull-less seed in C.pepo was controlled by one pair of different nuclear genes and "seed-hulled" was dominant to "seed-hull-less".