Barley competitive ability in coexistence with black oat or wild radish

Abstract

The objective of this study was to investigate the relative competitive ability of barley crop with the weed species of black oat or radish. Three experiments were conducted under greenhouse at UFPel in a completely randomized design, with four replications, and treatments arranged in a replacement series. The proportions of barley plants and competitors of black oat or wild radish were: 100:0, 75:25, 50:50, 25:75 and 0:100, always with a total population of 578 and 770 plants m -2 for black oat and wild radish, respectively. The variables evaluated were plant height; leaf area and shoot dry mass. Statistical analysis was performed by applied diagrams to the replacement series and interpretations of competitiveness indices. Barley has superior competitive ability to radish but below the oat. For barley, the interspecific competition with oat is more harmful, while in competition with wild radish has independent if competitor is own crop or weed.Additional keywords: Avena strigosa; Hordeum vulgare; interference; Raphanus sativus. ResumoO objetivo deste trabalho foi investigar a habilidade competitiva relativa da cultura da cevada com as espécies daninhas aveia-preta ou nabo. Foram realizados três experimentos em casa de vegetação, em delineamento completamente casualizado, com quatro repetições, sendo os tratamentos arranjados em série de substituição. As proporções de plantas de cevada e dos competidores aveia-preta ou nabo foram: 100:0, 75:25, 50:50, 25:75 e 0:100, com população total de 578 e 770 plantas m -2 , para aveia-preta e nabo, respectivamente. As variáveis avaliadas foram estatura, área foliar e massa seca da parte aérea. A análise estatística foi realizada por diagramas aplicados aos experimentos substitutivos com as interpretações dos índices de competitividade. A cevada apresenta habilidade competitiva superior ao nabo, mas inferior à aveia-preta. Para a cevada, a competição interespecífica com aveia-preta é mais prejudicial, enquanto que em competição com nabo independe se o competidor é própria cultura ou a planta daninha.

Morphological and physiological changes in barley cultivars under black oat competition

“…The LA for both the barley and the competitor presented similar behavior when observed for DM, with consistent losses for both species, and for all of the barley cultivars when in competition, with a mean reduction in the PRTs of about 40-50% concerning their respective controls (Figure 2). Similar results were observed by Fontana et al (2015) when working with barley and competing with black oats. They showed concave lines for the DM and LA of barley, indicating their lower competitiveness when compared with the weed.…”

“…In recent years, black oats have been infesting the southern Brazilian barley fields strongly, due to their higher occurrence and abundance, especially in those areas that are managed with black oat for livestock forage, and for soil cover crops with a notillage system (Tafernaberri Jr et al, 2012;Fontana et al, 2015;Forte et al, 2018). In addition, black oat has a high rusticity, with a low soil fertility requirement, rapid growth, and an initial development that is increasing the competitive potential of the species (Tafernaberri Jr et al, 2012).…”

“…Several studies have reported the competitive ability of crops, such as weeds, with reductions of up to 79% in the barley biomass and grain yield, due to the competition (Pilipavicius et al, 2011;Wanic et al, 2013). It is also essential to verify the influence of plant density on the competitive abilities of barley against black oat (Fontana et al, 2015;Andrew, Storkey, 2017).…”

“…Research studies involving physiological characteristics in a competition study between barley and black are scarce, as well as other studies of competition between the species that are influenced by the physiological and morphological parameters (Concenço et al, 2009;Fontana et al, 2015;Baldessarini et al, 2020). The present study hypothesizes that there is a differentiation in the competitive abilities of barley with black oats among the cultivars.…”

Interference Between Signal Grass and Cinderella Weed

“…Experiments in the replacement series are typically used to evaluate the coexistence between crops and weeds (Santos et al, 1997;Yamauti et al, 2011;Fontana et al, 2015) in order to understand which is the better competitor among species or biotypes and how these species interact among themselves within a constant population density (Passini et al, 2003).…”