Use of SIGS (Spray-Induced Gene Silencing technology) as an innovative weed control of very problematic weeds such as Alopecurus myosuroides (Black-grass)

Alopecurus myosuroides, Black-Grass (BG) is a problematic weed species in many autumn and spring sown crops, leading to huge yield losses.

Control of such a weed includes intensive herbicide spraying, raising environmental concerns, and resulting in herbicide resistance. Hence, there is an urgent need to develop alternative means for chemical weed control.

RNA interference is a conserved cellular mechanism mediated by naturally occurring double-stranded RNA (dsRNA) and small RNAs (sRNAs) that can target mRNAs for destruction.

Spraying weeds with dsRNAs that target essential weed genes (spray-induced gene silencing [SIGS]) can lead to better weed control.

This project aims to develop and evaluate SIGS to control weeds such as BG.We propose to increase understanding about: 1) If SIGS application of dsRNA and sRNAs delivered via clay nanosheets can control BG. 2) Risk associated with SIGS on weeds - if there are any on crops and their surrounding microbiome and the harvested yields 3) The mechanisms of sRNAs uptake, transport and silencing of host genes in BG.

We will use different omics technologies on dsRNA treated weed, including extracellular vesicles (sRNA, mRNA), combined with functional assays, to understand the sRNA transport mechanisms and select SIGS targets. We will test SIGS in the greenhouse and in field conditions for activity against weeds.

SIGS has a unique potential to provide environmentally benign, sustainable weed control that is GMO-free.