Diversity of weed flora in wheat depending on crop rotation and fertilisation

Abstract

The paper analyses weed fora in wheat depending on crop rotation and fertilisation in a twenty-year period. In both studied periods (1990 and 2010) the total of 49 weed species were determined on different variants of crop rotation, while 20 weed species were found in both studies. In the frst research period, in 1990, there were 16 differential species, which were not found in 2010, while in the second research, after 20 years, there were 13 new weed species, which had not been previously determined. In the second research period, the foristic diversity was signifcantly reduced, and in certain variants of crop rotation (three-year rotation, unfertilised three-year rotation and twelve-year rotation) the number of species was reduced two times. In both studied periods, the dominant species were weed-ruderal plants, with the signifcant share of segetal plants, while the most common life forms were therophytes from the T4 group. Apart from the positive effects of crop rotation and fertilisation on reducing weediness, the paper also focuses on the presence of species important for biodiversity conservation, such as Fumaria offcinalis L. from the category of endangered species, as well as seven other species from the category of vulnerable species - Centaurea cyanus L., Consolida regalis s.F.gray, Papaver rhoeas L., Viola arvensis Murr., Lathyrus tuberosus L., Ranunculus arvensis L. and Lamium amplexicaule L., which are most likely to survive among crops.