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2000多年前的我国秦朝,劳动人民用母马和公驴交配产生的骡子,综合了马和驴的优点,具有挽力大,耐粗饲,适应性强的特点,这是生物中人为利用杂种优势的最早记载。而谓杂种优势是指两个遗传性不同的个体杂交产生的第一代(F_1),优于父母双亲的现象。从本世纪初开始,杂种优势已广泛应用于农作物中,使作物的产量、品质及适应性大大提高,被称作育种史上的“革命”。要利用杂种优势,首先要得到杂交种。对于雌雄异花作物,如玉米,或者雌雄同花但繁殖系数较高的作
More than 2,000 years ago, in our country Qin Dynasty, the working people mare and male donkey mating mule, integrated the advantages of horse and donkey, with the advantages of big pull, resistance to rough feeding, adaptability, which is human use of biological The earliest recorded heterosis. The so-called heterosis refers to the first generation (F_1) produced by the crossing of two hereditary individuals, which is superior to the parents’ parents. Since the beginning of this century, the heterosis has been widely used in crops and greatly improved the yield, quality and adaptability of crops. It is called “revolution” in breeding history. To take advantage of heterosis, first get the hybrids. For dioecious crops, such as maize, or monoecious but reproductive coefficient is higher