**1. Introduction**

Oilseed rape (*Brassica napus* L.) is among the oldest crops grown in the world. It belongs to the flowering plant family *Brassicaceae*. This family is also called *Cruciferae* or the mustard family. It includes around 3 thousand plant species. The characteristic attribute of plants from this family is the arrangement of four flower petals in the shape of a cross. Historically, many species from the *Brassicaceae* family, e.g., brown and oriental mustard, Brussels sprouts, broccoli, cabbage, cauliflower, kale, kohlrabi, napa, oilseed rape, rutabaga, turnip, etc. have been cultivated for their edible parts: buds, flowers, leaves, roots, stems, and seeds. Oilseed rape is currently one of this family's most widely cultivated members [1–3].

Due to the absence of populations of its wild form, the origin of oilseed rape is not fully elucidated. However, the available knowledge suggests that this herbaceous plant originated from the eastern Mediterranean and west Asian region. It is supposed to be derived about seven and a half years ago from spontaneous hybridisation between turnip rape (*Brassica rapa* L.) and cabbage (*Brassica oleracea* L.). The studies suggest that currently, several B. napus subgenomes are present: the subgenome evolved from the ancestor of European turnip, and the subgenome evolved from the common ancestor of broccoli, cauliflower, Chinese kale and kohlrabi [1, 2, 4].

Historical records indicate that the cultivation of *Brassica* genus by humanity started many years ago. Plants from this genus are known to be widely cultivated by humans more than 10 thousand years ago. Oilseed rape was cultivated in India for more than 6 thousand years and spread to China and Japan 2 thousand years ago. Later, starting from the 13th century, due to the ability to grow in relatively low temperatures and successfully reproduce with little heat, oilseed rape was cultivated in Europe. The seeds of early oilseed rape varieties were avoided to use as a food oil source, as they contained high levels of erucic acid, which has a bitter taste and can cause heart diseases. However, these negative aspects were ignored by the poor during times of poverty and crisis [1, 3, 5].

In the following centuries, oilseed rape had a limited industrial use. Apart from being used for edible purposes, due to its oil property of emitting white smokeless flame when burning, since the 16th century, it was also widely used for lighting. The list of oilseed rape application possibilities expanded with the development of steam power. During this period, the unique property of oilseed rape oil to stick to water and steam-washed metal surfaces better than other lubricants was discovered. The great need for oilseed rape oil as a lubricant for rapidly increasing forces during World War II also affected the expansion of global B. napus seeded areas. For example, before World War II, oilseed rape was grown only in small trials for research purposes in Canada. The results of these trials revealed the ability of oilseed rape to grow both in eastern and western parts of this country and stimulated the expansion of this plant [1, 3].

Another surge in the worldwide interest in oilseed rape in the 20th century appeared when in the 1970s, the 0 and 00 type varieties with low erucic acid and glucosinolates were developed. Varieties grown until then did not meet the everincreasing needs of edible oil and protein feed, as their seeds had up to 52% erucic acid and 8% glucosinolates. The first 00-type varieties were registered in Western Europe in 1986. Their seeds contained no more than 2% of erucic acid, no more than 20 μmol/g of glucosinolates of air-dried seeds, and no more than 40% of crude fat [2, 3].

Later, especially in the last decades, the cultivated areas expanded even more with the development of breeding, which resulted in the improvement of desirable traits (greater seed yield, earlier maturity, disease, and pod shatter tolerance). The new agronomical advantages allowed oilseed rape to be increasingly grown in new countries and under different conditions [2, 5].
