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现行高中生物课本中一直把单倍体说成是高度不育的。实际上,关于这个问题应依不同情况而定。 一、单倍体 单倍体是指:含本物种配子染色体数的个体。因此可知单倍体并不等于含一个染色体组,它可以含有一个染色体组,也可含多个染色体组,这可依原物种是几倍而定,如玉米（二倍体）的单倍体含有一个染色体组;普通小麦（六倍）体）的单倍体含三个染色体组;陆地棉（四倍体）的单倍体含两个染色体组。由于自然界的高等生物都是通过有性生殖产生后代,单个的精子或卵子往往自行死亡。因此单倍体在自然界的出现率是极低的。只有在人工条件下,通过花粉培养等方式才能很容易地得到单倍体。
The current high school biology textbooks have always referred to haploids as highly sterile. In fact, this issue should be determined according to different circumstances. 1. Haploids Haploids are individuals that contain the chromosome number of the gamete of the species. Therefore, we can see that haploid does not equal to one genome, it can contain one chromosome group, it can also contain multiple chromosome groups, which can be determined by the original species is several times, such as corn (diploid) haploid A haplotype containing one genome; common wheat (six-fold) contains three genomes; a haplotype of upland cotton (tetraploid) contains two genomes. Because natural higher organisms produce offspring through sexual reproduction, individual sperm or eggs often die by themselves. Therefore, the incidence of haploids in nature is extremely low. Haploids can be easily obtained by pollen culture only under artificial conditions.