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一、杂种优势的意义 Shull 1914年首先提出杂种优势一词,用来表达杂合体的特殊刺激作用,包括细胞分裂、生长和其他生理活动。以后从杂种植株器官组织的大小,产量和长势等的增强,扩大到生物体生存的优势,如适应、选择和生殖等。Dohszansky1930年提出用常规杂种优势表达上述外加的杂种性质。Powes1944年和Stern1948年又把劣势表现包括在内,叫负杂种优势。 从进化观点来看,负杂种优势是正杂种优势的逆转,通过正负杂种优势的摆动,循环不断地调节群体对环境变化的反应而产生适应。Shull1948年提出杂种优势是杂结合的一种刺激作用,但是优势也可以由于同质
First, the significance of heterosis Shull first proposed in 1914 the term heterosis, used to express the special stimulation of hybrids, including cell division, growth and other physiological activities. From the hybrid plant organs after the size, yield and growth, etc., expanded to the advantage of living organisms, such as adaptation, selection and reproduction. In 1930, Dohszansky introduced a detailed description of the characteristics of the living room. Powes 1944 and Stern1994 prosecutions were included in the presentation, called negative heterosis. From the evolutionary point of view, negative heterosis is the reversal of positive heterosis, through the swing of the positive and negative heterosis, the cycle constantly adjusts to the community’s response to environmental changes to adapt. Shull introduced in 1984 a perfect combination of features, but the advantages can also be due to homogeneity