The Influence of Long-Term Different Crop Rotations and Monoculture on Weed Prevalence and Weed Seed Content in the Soil

Abstract

Equally effective way to achieve sustainable farming and the challenge set by the European Commission on 20 May 2020: proper crop rotation and thus reduction of the quantity of on-farm chemicals. Long-term stationary field experiments were established in 1966 at Vytautas Magnus University Experimental Station (54°53′ N, 23°50′ E). The study was conducted with intensive, three-course, field rotation with row crops, for green manure crop rotations, and rye monoculture as well during the last 5-year period of a 50-year investigation to determine the effect of crop rotation combinations and rye monoculture on weed density and seed bank and grain yield. In cereal crops, weed counting was performed twice: weed density was determined before the application of herbicides, and weed counting was done before the harvest. Weed seedlings were counted, their botanical species were determined, annual and perennial weed number was estimated. Weed seed bank was established before primary tillage in soil. The results obtained confirmed the hypothesis that with climate change and intensive farming, long-term crop rotations are likely to increase crop productivity, reduce weeds and weed seed banks in the soil, and thus contribute to maintaining agroecosystem sustainability. The winter rye 1000 grain weight and yield decreases as weed mass increases showing strong negative correlations: y = 475.56 − 11.93x, r = −0.91, p ≤ 0.05; y = 82.97 −14.82x, r = −0.97, p ≤ 0.01. Reseeding of rye crops leads to a growing prevalence of weeds such as Equisetum arvense L. and Mentha arvensis. Crop structures these days are dominated by cereals, which inevitably increase the spread of weeds, and therefore, the importance of crop rotations increases in the context of intensive farming.

How Do Long Term Crop Rotations Influence Weed Populations: Exploring the Impacts of More than 50 Years of Crop Management in Serbia

“…Monoculture provides some empty space and untouched resources for weeds [3]. Weeds are adapted for these conditions and will use the resources to grow and produce seeds [22]. Crop rotation disturbs these niches and prevents weeds from finding their place for establishing, thus breaking their cycle [23].…”

Soil Seed Bank in a Pre-Erosion Cereal-Grass Crop Rotation

“…According to Butkevičienė et al [ 22 ], the research data show that 20.2 to 71.4 thousand weed seeds can be found in 1 m 2 of the cultivated soil in the depth of 0–20 cm. In 1 m 2 of the uncultivated soil (natural meadow) in the depth of 0–15 cm, 4.3 thousand weed seeds were found [ 23 ].…”

“…It is usually indicated that only a few species compose the highest part of the soil seed bank. The authors indicated that soils are mostly contaminated by the seeds of Chenopodium album L. [ 22 , 40 , 41 ], whose annual decline rates were about 14–41% [ 42 ]. In our research, the seeds of Chenopodium album prevailed in the soil seed bank in the spring of 2020, while in the autumn (2020) and in the spring and autumn of 2021, they comprised from 2.5 to 10.8% of the whole seed bank.…”

Herbicide Use in the Era of Farm to Fork: Strengths, Weaknesses, and Future Implications

“…Under the context of each one of these axes, several different techniques and methods have been studied and evaluated within the EU, providing a wide range of management alternatives. The diversification (both in space and in time) of cropping systems includes the adoption of crop rotations, cover crops, intercropping, and landscape arrangement (Błażewicz-Woźniak et al, 2015 ; Giuliano et al, 2016 ; Kuht et al, 2017 ; Weber et al, 2017 ; Dhima et al, 2018 ; Royo-Esnal et al, 2018 ; Scavo et al, 2019 , 2021 ; Butkevičienė et al, 2021 ). Cultivar selection could be based on certain agronomic traits that enhance competitive abilities and can potentially suppress weeds more efficiently (Kokare et al, 2014 ; Karkanis et al, 2016 ; De Vita et al, 2017 ; Rasmussen et al, 2021 ).…”