Relating Ambrosia artemisiifolia and other weeds to the management of Hungarian sunflower crops

Abstract

The weed control of sunflower is a 'great challenge' for farmers throughout the World. The main goal of this study is to identify management and environmental factors which determine the weed species composition of sunflower fields. Altogether 49 sunflower fields across Hungary were surveyed for their weed flora, and 11 environmental and 19 management factors (including the use of mechanical weed control and 6 herbicide treatments) were also recorded for the same fields. Using stepwise backward selection this set of predictors was reduced to a minimal adequate model containing 14 terms explaining 37.8% of the total variation in species data. The net effects of 5 variables on species composition were significant, these were soil Mg and Ca content, preceding crop, temperature, and field size. We also performed exploratory forward/backward model selection to reveal influential predictors for several predetermined species groups and individual species. Most of the herbicides appeared to be effective against annual grass species, but no herbicide was universally effective against broad-leaved weeds. Almost all types of weeds were efficiently reduced with mechanical weed control. We obtained a relatively high share of environmental factors in the variation of species composition, which suggests that the success of agrotechnical treatments in sunflower fields strongly depends on a complex of edaphic and climatic constraints. The abundance of the most troublesome weed, Ambrosia artemisiifolia was positively correlated with high soil Ca content, lower temperature, preceding crop cereal, and lower field sizes, while it seemed to be most sensitive to fluorchloridon and propisochlor application.2

Weed species composition of small‐scale farmlands bears a strong crop‐related and environmental signature

“…A strong negative relationship between field size and weed diversity at the landscape level has often been reported due to a higher associated heterogeneity of cultivated areas and a larger edge:area ratio in smaller field sizes (Marshall et al ., ; Gaba et al ., ; Fahrig et al ., ). Some mechanical operations are less efficient in smaller fields, and farmers cultivating small fields tend to have limited access to weed management technology or expertise (Pinke et al ., ). In our study, this effect, albeit significant, was less pronounced (field size ranked only 12th among the explanatory variables), as our data cover only a narrow range of field sizes (most fields in our survey were small, 59% had ≤1 ha).…”

“…To develop efficient, sustainable and environmentally friendly weed control practices, it is important to understand the drivers of weed presence and abundance on cultivated lands (Swanton et al ., ). We need to investigate how the interaction between farming and weed management systems and the environment affects the composition of weed vegetation in different croplands (Pyšek et al ., ; Pinke et al ., , , ).…”

Spread of common ragweed (Ambrosia artemisiifolia L.) on arable land in the �itn� ostrov

“…In Hungary, 700,000 ha of farmland was heavily infested (extent of infestation ˃10%) in 2003 (Tóth et al, 2004). The most frequently infested crops within Central Europe are spring-sown crops like sunflower, corn, soy bean and stubble fields (Týr et al, 2009;Kovács, 2010;Pinke et al, 2012Pinke et al, , 2013. For example, A. artemisiifolia decreased grain yield of corn by 19.5% and above ground corn biomass by 18.5% at density of 5 ragweed plants*m -2 in Slovakia (Vereš et al, 2011), sunflower yield in Hungary was decreased by 27% at density of two ragweed plants*m -2 (Béres, 1985) up to 33% at the density of 10 ragweed plants*m -2 (Kazinczi et al, 2007).…”

“…Ambrosia grows in dry fields and pastures, vineyards, waste grounds, along rivers, canals, bird feeding places, roads and railways. Heavy infestation occurs around agricultural and industrial objects and forms dense populations especially in agricultural land within lowlands (Pál, 2004;Pinke et al, 2011;Medvecká et al, 2012;Pinke et al, 2013;Kazinczi and Novák, 2014;Májeková and Zaliberová, 2014;Milakovic et al, 2014). On the other hand, while ragweed grows abundantly in certain habitats, other habitats are hardly populated (Skjøth et al, 2010).…”

Ambrosia artemisiifolia in the Czech Republic

“…However, factors other than climate are investigated only occasionally and over a limited area in analyses of A. artemisiifolia distribution. Besides climatic factors, landscape variables explain the current distribution of A. artemisiifolia in Austria (Essl et al 2009) and soil characteristics, position within a field and crop type and cover in arable fields in Hungary (Pinke et al 2011(Pinke et al , 2013.…”