The spread of short-lived weeds in Zemgale [Latvia] | Īsmūža divdīgļlapju nezāļu izplatība Zemgalē
2019
Lapins, D., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Kopmanis, J., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Melngalvis, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Sanzarevska, R., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Putniece, G. [and four others], Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
Directive 2009/128/EC of the European Parliament and of the Council stipulated that all Member States of the European Union had to operate according to the principles of Integrated Pest Management as of 1 January 2014. The aim of the research was to explain the occurrence of field weed species and its changes in agrocenosis in the farms of Zemgale region depending on the species of grain and forecrop, as well as the choice of technologies. Weed monitoring was conducted from 2013 to 2017. In order to perform weed monitoring in the research area, 12 different farms were randomly selected for uniform coverage of the area. Weed surveys were conducted in six sown fields or planted fields in each of the farms. In the weed monitoring sites, weed surveys were performed according to the occurrence method (Rasins, Tauriņa, 1982). Weed surveys were conducted once in the vegetation period (3rd decade of July – 2nd decade of July) determining the composition of the weed population, the dominant species and their distribution level in the fields of various arable crops. Weeds were identified at species level as close as possible, but where it was not possible – at the level of the family. The research findings show that in Zemgale weed species could be divided into the following four dominant groups according to their occurrence: 1) field pansy (89% of all fields in all years); 2) wind buckwheat (66%); 3) red dead-nettle, cleavers (distribution 57% and 54%); 4) field speedwell, goosefoot and sunspurge with the prevalence of 42% to 48% in all fields in all years. The significantly highest weed infestation in 2014 was because overwintering of winter cereals was unsatisfactory, many fields had to be redrilled, sowing of summer cereals and their care was delayed. But the year 2017 was characterized by increased precipitation and germination; also growing conditions were often unsatisfactory not only for crops but also for weeds. The wintering dicotyledonous weeds with the same distribution potential as the main dominance of field pansy were: field chamomile; shepherd's purse, common cornflower, field penny-cress, volunteer winter oil seed rape; field forget-me-not, forking larkspur, field speedwell. In warm winters in Zemgale also cleavers, common fumitory, red dead-nettle overwinter. In order to successfully limit the spread of short-lived dicotyledonous weeds, it is necessary to changes herbicides each year, which significantly reduces the prevalence of dominant dicotyledonous species.
اظهر المزيد [+] اقل [-]