Comparing the emergence of Echinochloa crus‐galli populations in different locations. Part I: Variations in emergence timing and behaviour of two populations

Abstract

Echinochloa crus-galli (L.) P. Beauv. is one of the most important weeds. It is distributed worldwide and has adapted to diverse habitats and climatic conditions. This study aimed to compare the emergence patterns of two populations of E. crus-galli from different environments at 11 locations across Europe and the Middle East. Seeds of the two populations were collected from maize in Italy and from spring barley in Norway and were then buried in soil in autumn 2015. In the spring of 2016, the soil was disturbed around the usual seedbed preparation date in each location and emergence was recorded. The soil was again disturbed a year later and emergence was recorded for a second season. Total emergence, the times of onset, end and to 50% emergence and the period between 25% and 75% of emergence were analysed by | 193 ROYO-ESNAL Et AL.

Comparing the emergence of Echinochloa crus‐galli populations in different locations. Part II: similarities and threshold parameters

“… a Climate classification according to the updated Köppen–Geiger classification (Kottek et al, 2006): Cfa, temperate with no dry season, hot summer; Cfb, temperate with no dry season, warm summer; Csa, temperate with dry and hot summer (warm Mediterranean); Dfb, cold with no dry season and warm summer (continental). For specific climatic conditions of the experimental seasons (2015–16 and 2016–17), see Royo‐Esnal et al (2022). …”

“…With this background, the Working Group on Germination and Early Growth (WG‐GEG) of the European Weed Research Society (EWRS) studied the emergence of two populations of E. crus‐galli , one from Italy and the other from Norway, at 12 locations in Europe and the Middle East (Royo‐Esnal et al, 2022). In that research, the population from Norway (NO) showed higher emergence at higher latitudes and lower emergence at lower latitudes, compared with the Italian population (IT).…”

“…In this paper, the main objective was to compare the emergence patterns of the NO and IT populations (Royo‐Esnal et al, 2022) with those of local seed populations collected in 12 locations. A further objective was to investigate whether the NO, IT and local populations could be grouped according to similarities in emergence characteristics.…”

“…A further objective was to investigate whether the NO, IT and local populations could be grouped according to similarities in emergence characteristics. Additionally, and based on the differences reported by Royo‐Esnal et al (2022), T b was estimated for the NO and IT populations.…”

“…The total number of emerged plants (E tot ) was analysed separately for each locality because of the significant 'population by locality' interaction for the two common populations(Royo-Esnal et al, 2022) and because local populations were unique to each locality. One-way anova and post hoc multiple comparison testing were performed based on Fisher's least significant difference.Data were arcsin-square root transformed, wherever necessary, to meet the basic assumptions of normality and homoscedasticity.…”