Winter oilseed rape and weed competition in organic farming using non-chemical weed control

Abstract

One of the reasons why the area sown with oilseed rape in organic farms is not expanding is problems with weed, disease, and pest control as well as low seed yield. There is a lack of investigations on oilseed rape cultivated in an organic system, especially employing innovative weed control methods. To fill this gap in knowledge, field experiments were conducted at the Experimental Station of Aleksandras Stulginskis University in 2012-2013 with the aim of identifying and assessing the impact of different non-chemical weed control methods (thermal -TWC, mechanical -MWC and smothering -SMT) on weed competitiveness in winter oilseed rape (Brassica napus L.) crops during the autumn vegetation period in an organic farming system with and without the use of plant bio-activators in a soil with a regular (23-25 cm) (1 st experiment) and with a thickened (48-50 cm) (2 nd experiment) humus layer. It was found, that compared with thermal and mechanical weed control, in the treatment using smothering weed control and spraying with plant bio-activators or not spraying, the density of winter rape crop in the soil with a regular humus layer was significantly (P ≤ 0.05) lower (1.2 to 5.3 times); in the soil with a thickened humus layer, the density of winter rape crop was 1.5 to 5.9 times lower. In winter oilseed rape during autumn vegetation period, 20-22 weed species were found, including 18-19 annuals. Stellaria media (L.) Vill., Veronica arvensis L., Sinapis arvensis L. and Capsella bursa-pastoris (L.) Medik. were the predominant weeds.In the soil with a regular and a thickened humus layer, thermal and mechanical weed control significantly (P ≤ 0.05) decreased the number of weed seedlings (1.1 to 1.9 times) when plant bio-activators were used compared with the smothering treatment. Weed control in the smothering treatment in the soil with a regular and thickened humus layers was not effective. Mechanical weed control was more efficient than thermal. Application of plant bio-activators increased the efficiency of the thermal weed control.

The effects of water steam on weeds and fungal diseases in the stands of onion

“…Researchers have indicated that thermal weed control is more effective than mechanical weed control (Virbickaitė et al, 2006;Ascard et al, 2007). However, other researches came up with opposite conclusions (Velička et al, 2016).…”

“…A major problem that organic farmers face is weed management (Edesi et al, 2012). In most organic farms, weeds are controlled mechanically (Jodaugienė et al, 2008;Van der Weide et al, 2008;Fontanelli et al, 2009;Pannacci, Tei, 2014). Another increasingly used weed control method is thermal weed control.…”

“…Another increasingly used weed control method is thermal weed control. Thermal weed control can be used in various crops (Shrestha et al, 2013;Velička et al, 2016) In different countries, diverse methods of thermal weed control are used in organic farms: flaming (Sivesind et al, 2012), combustion gases (Ulloa et al, 2010;2012;Datta, Knezevic, 2013), hot foam (Cederlund, Börjesson, 2016), hot water (De Cauwer et al, 2014) and water steam (Melander, Kristensen, 2011;Shrestha et al, 2012;Vidotto et al, 2013). Researchers have indicated that thermal weed control is more effective than mechanical weed control (Virbickaitė et al, 2006;Ascard et al, 2007).…”

Simple model based on artificial neural network for early prediction and simulation winter rapeseed yield

“…Plant yielding depends on a large number of factors that are often correlated with each other and directly or indirectly affect the yield of a given plant. Soil factors (pH, structure, organic matter content, nutrient level), weather and climatic factors (air temperature, rainfall, insolation), soil tillage technologies, plant varieties, technology and fertilization level, plant protection, harvesting technology as well as crop rotation can be taken into account the most often (Khairunniza-Bejo et al 2014;Velička et al 2016).…”

Nutrient content, fat yield and fatty acid profile of winter rapeseed ( Brassica napus L.) grown under different agricultural production systems

“…However, this is associated with intense fertilization and the application of large amounts of pesticides, which may negatively impact the consumer. It is thus essential to develop and improve edible oil production systems to make them both satisfying to the farmer and non-threatening to the consumer (Velicka et al, 2016). Fertilizer applications, especially on nutrient deficient soils, can therefore increase crop yields and quality (Albert et al, 2012;Malhi, 2012).…”