Herbicide Resistance of Centaurea cyanus L. in Poland in the Context of Its Management

Marta Stankiewicz-Kosyl,Ewa Tendziagolska,Małgorzata Haliniarz,Agnieszka Synowiec,Mariola Wrochna,Katarzyna Marcinkowska,Krzysztof Domaradzki,Grzegorz Skrzypczak,Anna Wenda-Piesik,Witold Łykowski,Marcin Bednarczyk,Magdalena Sobolewska,Michał Krysiak

doi:10.3390/agronomy11101954

Abstract

Cornflower (Centaurea cyanus L.), one of the main weeds found among winter crops in Poland, has developed herbicide resistance (HR) to acetolactate synthase (ALS) herbicides, a finding first reported in 2006, and in recent years, farmers have been complaining about inadequate chemical control of this weed. This study aimed to characterise the current state of cornflower HR to ALS inhibitors and synthetic auxins in Poland and the agricultural practices in fields with herbicide-resistant populations. From 2017 to 2020, 159 seed samples together with the field history were collected across the country and biological tests performed in glasshouses. This revealed that 47 populations of C. cyanus were cross-resistant to both tribenuron and florasulam, 28 and 8 populations were single resistant to tribenuron and florasulam, respectively, and 3 populations had developed multiple resistance to both ALS inhibitors and synthetic auxins, i.e., 2,4-D and dicamba. Resistant populations were found mostly frequent in northern Poland, but also in the eastern and western parts of the country. Based on a survey of farmers, the resistant populations were found in winter crops regardless of the tillage system (77% of fields with HR cornflower were mouldboard ploughed). Based on the proposed population treatment (PT) index showing the frequency of herbicide use during three consecutive seasons on farms with HR cornflower, the average PT for all the surveyed farms was 5.4. The highest PT of 7.4 was found in the province of Warmia-Masuria in northern Poland.

Highlights

In modern agriculture, the phenomenon of herbicide-resistant weeds represents a serious threat to both crop yield [1,2] and agricultural biodiversity [3]
The first cases of herbicide resistance were identified in Poland in the early 1980s and concerned weeds that were resistant to photosystem II inhibitors, e.g., Conyza canadensis and Capsella bursa-pastoris, followed by Amaranthus retroflexus and Chenopodium album [8,9]
The study was a part of the 3-year national project entitled “Anti-resistance strategy in weed management as an important factor in the sustainable development of agroecosystems” concerning herbicide resistance in 4 important agricultural weeds in Poland: C. cyanus, P. rhoeas, A. myosuroides and A. spica-venti

Summary

Introduction

The phenomenon of herbicide-resistant weeds represents a serious threat to both crop yield [1,2] and agricultural biodiversity [3]. In Poland, the situation is different since, according to Heap’s list, the majority of herbicide-resistant cases concern dicotyledonous weeds (12 different species) and only four monocotyledonous species, which together constitute 25 cases of herbicide resistance in the country [4]. The first cases of herbicide resistance were identified in Poland in the early 1980s and concerned weeds that were resistant to photosystem II inhibitors, e.g., Conyza canadensis and Capsella bursa-pastoris, followed by Amaranthus retroflexus and Chenopodium album [8,9]. These are common dicotyledonous species in the country and are found among a variety of crops and in orchards. Heap’s list for Poland features rarer weed species that have evolved herbicide resistance, such as Epilobium ciliatum, which is resistant to photosystem II inhibitors in orchards [10], and cornflower (Centaurea cyanus L.), which is resistant to acetolactate synthase (ALS) inhibitors (Herbicide Resistance Action Committee (HRAC) group 2) as well as dicamba (HRAC 4)

Objectives

Methods

Results

Discussion

Conclusion