Taxon Within a Triticum Species

In the second half of the nineteenth century, many works on taxa and classifications below species were carried out on the genus Triticum. For instance, Alefeld (1866) used characteristics of spike and grain to classify varietas. Kornicke (1885) further developed and made a number of varietas names, some of which are still used by some people. They identified varietas using the characteristics such as spikes with awns or awnless, hairy or hairless glumes, spike color (white, red, black), and grain color (white, red). In the twentieth century, such artificial classification was adopted by Вавилов, Фляксбергр, Туманян, Якубцнер of the former Soviet union school and some scientists in other countries, for example Percival, making classification very complicated. In our opinion, over-complex classification is not necessary in scientific theory and useless in productive practice. The classification on the basis of simple phenotypic traits cannot effectively reflect the naturally phylogenetic relationships in many cases. However, in cultivated crops, cultivar that is developed by artificial selection on human economic purposes is a useful unit with economic significance. Correspondingly, in the natural environment, varietas formed by natural selection is the natural unit of evolutionary adaptation.