Crop residue retention suppresses seedling emergence and biomass of winter and summer Australian weed species

Abstract

Crop residue retention could affect the emergence and biomass of weeds in different ways. A summer and winter pot study was conducted to evaluate the effect of different amounts of sorghum and wheat residue on the emergence and biomass of 12 summer and winter Australian weeds. The equivalent amount of sorghum residue to 0, 1, 2, 4 and 6 t/ha was used in the summer study and winter weed seeds were covered with wheat residue equivalent to the amount of 0, 1, 2, 4 and 8 t/ha in the winter study. The emergence and biomass of Amaranthus retroflexus and Echinochloa colona was not affected by sorghum residue treatment. For other summer weeds, the use of the 6 t/ha sorghum residue treatment resulted in 59–94% reductions in biomass compared to no‐sorghum residue retention. Similarly, the application of 8 t/ha wheat residue in the winter study resulted in a reduced biomass of 15–100% compared to no‐crop residue treatment. The results demonstrated the high potential of using crop residues in eco‐friendly weed management strategies, such as harvest weed seed control tactics.

Emergence pattern of horseweed (Erigeron canadensis L.) accessions across Nebraska

“…residue levels (e.g., absence of a physical barrier on the soil surface) may result in higher weed emergence and establishment (Chauhan and Johnson 2011;Mobli and Chauhan 2020a). Daily temperature fluctuation has been reported not to influence the emergence of horseweed, and light exposure is not a mandatory factor for its germination (Nandula et al 2006;Ottavini et al 2019).…”

Soil Health: New Opportunities to Innovate in Crop Protection Research and Development

“…Another opportunity for innovation is to focus on crop protection challenges that consistently occur when soil health practices are implemented. For example, surface residue retention protects soil organisms, maintains soil moisture (Turmel et al, 2015), and suppresses weeds (Mobli and Chauhan, 2020), but can also exacerbate waterlogging and result in lower yields in areas experiencing high rainfall (Rusinamhodzi et al, 2011). If it rains just before or during planting, lowering soil temperatures, seeds may remain quiescent in the soil and be more vulnerable to pathogens and invertebrates (Gamfeldt and Roger, 2017).…”