Weed Seed Decay in No-Till Field and Planted Riparian Buffer Zone

Abstract

Field management practices can alter the physical and chemical properties of the soil, also causing changes to the seed bank. Alterations can also occur to the soil microbial community, which in turn can increase or diminish the process of weed seed decay. In this research, the issue of seed degradation was studied in an undisturbed and a no-till soil, trying not only to uncover where seeds are more degraded, but also to investigate the microbial activities that could be involved in this process. Six different weed species, commonly found in northern Italy, were used: Abutilon theopharsti, Alopecurus myosuroides, Amaranthus retroflexus, Digitaria sanguinalis, Portulaca oleracea and Sorghum halepense. Seed decay was tested in two different sites, a no-till field and the adjacent buffer zone. Soil microbial activity was also measured using the Fertimetro, an approach based on the degradation of cotton and silk threads buried in the soil for one week. Degradation of the buried seeds was higher in the no-till field soil than in the buffer strip for all the studied species as was the microbial cellulolytic activity. Even though the buffer strip soil is an undisturbed habitat and resulted as having higher organic matter, the no-till soil conditions appeared more unfavourable to seed viability. Our findings suggest that no-till management can improve weed seed suppression in the soil. Moreover, cellulolytic microorganisms play an important role in seedbank longevity, so cellulolytic activity surveys could be used as an early monitoring bioindicator for weed seed suppression in soil.

Effect of Crop Residues on Weed Emergence

“…In the surface layer of a mature no-till soil, crop residues interact with the soil and affect physical, chemical, and biotic soil properties. Therefore, weed seeds could also be affected by this interaction [3,[49][50][51]. Given the complexity of the factors involved, more studies in no-till fields, with different weed species and different types and amounts of residues, are necessary to improve our knowledge of weed-residue cover interactions.…”

Seed Germination of Sunflower as a Case Study for the Risk Assessment and Management of Transgenic Plants Used for Environmental Remediation in South Korea

“…Chantre et al [59] demonstrated that seed decay increases as burial depth and period increase, and decay was further elevated by complementary water supply. Seed decay is highly affected by the activity of soil microorganisms influenced by the soil environment, including the soil temperature, moisture, and physicochemical properties [60,61]. Several studies have shown that the impact of fungicidal treatments on the survival of buried seeds is more pronounced in relatively wetter conditions [62,63].…”

Characterisation and dynamics of the fungal communities of Avena fatua and Echinochloa crus‐galli seeds in soil seed bank

“…At the same time, there are both antagonistic and mutually beneficial interactions between different bacteria and fungi (Chee‐Sanford et al, 2006; Diakaki et al, 2022; Pollard, 2018; Truyens et al, 2015). Seed decay rate in soil can depend on the morphology and composition of the seeds as well as the cellulolytic microbial activity in the soil (Nikolić et al, 2018). Ullrich et al (2011) reported that in one of the experiments they performed, the half‐life of weed seeds was negatively correlated to microbial biomass (both bacteria and fungi).…”