The sustainable management of the environment and crop production in modern agriculture involves dealing with challenges from climate change, environmental pollution, depletion of natural resources, as well as pressure to cope with dependence on agricultural inputs. Balancing crop productivity with environmental sustainability is one of the main challenges for agriculture worldwide. The emergence of weeds resistant to synthetic herbicides generates huge economic losses, so unconventional weed control strategies, especially those based on ecological principles, are very much needed in modern agriculture. Incorporating a natural eco-friendly approach—allelopathy—as a tool in an integrated weed control plan by growing specific crops or spraying fields with extracts containing allelopathic compounds can significantly reduce the use of herbicides. Allelopathy is considered a multi-dimensional phenomenon occurring constantly in natural and anthropogenic ecosystems, by which one organism produces biochemicals that influence the growth, survival, development, and reproduction of other organisms. The objective of this systematic literature review is to present a comprehensive overview of allelopathy, define this phenomenon, and classify allelochemicals. This paper also discusses and highlights recent advances, ongoing research, and prospects on plant allelopathy management practices applied in agriculture, and the underlying allelopathic mechanisms. The review suggested the holistic view of some allelochemicals as an ecological approach to integrated weed control and is an important contribution to future research directions of multidisciplinary programs, chemoinformatic tools, and novel biotechnology methods to plant breeding.

The aim of this study was to monitor the sediment, soil and surface water contamination with selected popular triketone herbicides (mesotrione (MES) and sulcotrione(SUL)), atrazine (ATR) classified as a possible carcinogen and endocrine disrupting chemical, as well as their degradation products, in Silesia (Poland). Seventeen sediment samples, 24 soil samples, and 64 surface water samples collected in 2014 were studied. After solid-liquid extraction (SLE) and solid phase extraction (SPE), analytes were determined by high-performance liquid chromatography (HPLC) with diode array detection (DAD). Ten years after the withdrawal from the use, ATR was not detected in any of the collected samples; however, its degradation products are still present in 41 % of sediment, 71 % of soil, and 8 % of surface water samples. SUL was determined in 85 % of soil samples; its degradation product (2-chloro-4-(methylosulfonyl) benzoic acid (CMBA)) was present in 43 % of soil samples. In 17 % of sediment samples, CMBA was detected. Triketones were detected occasionally in surface water samples. The chemometric analysis (clustering analysis (CA), single-factor analysis of variance (ANOVA), N-Way ANOVA) was applied to find relations between selected soil and sediment parameters and herbicides concentration. In neither of the studied cases a statistically significant relationship between the concentrations of examined herbicides, their degradation products and soil parameters (organic carbon (OC), pH) was observed.

Triketone compounds are considered to be less stable in the ecosystems in comparison with other herbicides. However, their degradation processes in environment are under investigation as both parents and degradation products can exhibit toxicity on non-target organisms. The objective of this research was to investigate the degradation of triketone herbicides: mesotrione, sulcotrione, and tembotrione, as well as their degradation products in soils and sediments. The degradation studies were conducted in soil and sediment samples with different physicochemical properties. All experiments were conducted under standard experimental conditions; therefore, it was possible to assess the influence of pH, organic carbon (OC) content of soils and sediments, and the sunlight on the stability of triketones and their degradation products. The conditions of extraction and chromatographic determination were optimized for the determination of triketones and their degradation products in laboratory-spiked sediment and soil samples. The triketone degradation products exhibited higher stability in soil and sediment samples in comparison with parent herbicides. Soil microorganisms accelerated the degradation of all investigated compounds. In alkaline soil and sediments, all analytes exhibited higher stability in comparison with the acidic sorbents. The influence of OC content in sorbents was not evident. Photodegradation was the main path of triketones decomposition in soils and sediments. Since the stability of triketone herbicides may be significant, depending on the environmental conditions, the monitoring of the concentration of these compounds and in particular their degradation products should be conducted under the field conditions.