Spray-Induced Gene Silencing to control sugarbeet diseases
- Reference number
- SM21-0041
- Start and end dates
- 220101-241231
- Amount granted
- 1 026 700 SEK
- Administrative organization
- Swedish University of Agricultural Sciences
- Research area
- Life Sciences
Summary
Cercospora leaf spot (CLS), caused by Cercospora beticola, is a fungal disease on sugar beet causing up to 50% yield loss. With ongoing climate change, an increased frequency of sporadic outbreaks has been observed in Sweden and Denmark. Furthermore, C. beticola could be spread by commercial table beet seed. No known genetic resistance and commercially available fungicide can completely stop, only slow down CLS. There is an urgent need to develop alternative means for CLS control. RNA interference is a conserved cellular mechanism mediated by naturally occurring double-stranded RNA (dsRNA) that can target mRNAs for destruction. Spraying dsRNAs that target essential pathogen genes onto plants or seeds (spray-induced gene silencing [SIGS]) can yield crop protection. This project aims to develop SIGS to control CLS. We propose to understand: 1) If SIGS can control CLS 2,) risk associated with SIGS if there are any on cultivated crops and their microbiomes 3) the mechanisms of sRNAs uptake and silencing of genes in C. beticola. Several C. beticola virulence factors have already been identified and will be evaluated as target genes for SIGS. We will use dual RNA sequencing of C. beticola – sugar beet interactions (sRNA and mRNA), combined with functional assays, to understand the transport mechanism of sRNAs. We will test SIGS in the greenhouse and field conditions with high throughput phenotyping. SIGS has the unique potential to provide sustainable control of CLS.
Popular science description
Sprayinducerad genavstängning för att kontrollera sockerbets sjukdomar Cercospora leaf spot (CLS), caused by Cercospora beticola, is a fungal disease on sugar beet causing up to 50% yield loss. With ongoing climate change, an increased frequency of sporadic outbreaks has been observed in Sweden and Denmark. Furthermore, C. beticola could be spread by commercial table beet seed. No known genetic resistance and commercially available fungicide can completely stop, only slow down CLS. Choices of effective crop protection chemicals is also becoming more limited due to increased stringency for approval of these chemicals. There is thus an urgent need to develop alternative means for crop disease control. Several plant pathogens have been shown to produce small RNA (sRNA) and double stranded small RNA (dsRNA) molecules which either dampen or even shut off the plant's immune system, in order to infect the plant. Plants can also naturally produce dsRNAs or sRNAs that target pathogen genes to fight off infection. There is therefore the possibility of bidirectional transport of dsRNA and sRNA between plants and pathogens during infection. How these small molecules are transported during infection is still unanswered. Conceptually, our new idea in this project proposal is to produce the dsRNA molecules in the laboratory, targeting essential C. beticola genes, and spray them onto sugar beet plants and tubers. Uptake of the sprayed dsRNAs by C. beticola should affect the activity of the specifically targeted genes when it is about to infect sugar beet tubers and plants, leading to inhibition of disease development. This strategy of disease control can also be called spray-induced gene silencing (SIGS) and is environmentally friendly and GMO free. The main aim of this project is to evaluate the prospect of developing SIGS to control CLS disease. Such approaches afford the possibility of reduced fungicide application, and promote a more natural environment, whilst also reducing the cost of farming.