RESUMEN
Satellite RNAs (satRNAs) are RNA molecules associated with many plant viruses and fully dependent on them for replication, encapsidation, and movement within the plant or transmission from plant to plant. Their classification is based on their length, functional protein-coding capacity, and RNA structure (whether linear or circular). They have been of interest for a long time as some of them, in particular systems, cause significant changes in the pathogenesis and epidemiology of plant viruses. The outcomes of how satRNAs affect pathogenesis depend on the components of the pathosystem: host plant species or variety, virus species or even strain, and the sequence of satRNA. These can be additionally affected by biotic and abiotic factors, for example, environmental conditions such as the presence of their vectors or ambient temperature. satRNAs may interfere with primary metabolism, signalling, plant defence [including post-transcriptional gene silencing (PTGS)], as well as the efficiency of virus transmission from plant to plant. In recent years, due to wider access to high-throughput technologies and the extension of studies on satRNAs to include the involvement of external factors in plant-virus-satRNA systems, we are gaining a broader view of the consequences of the presence of these small molecules in viral infections. This review presents the state of the art of satRNA interactions with the helper virus and host plant as well as the influence of satRNAs on the insect vector's behaviour. Moreover, areas requiring further research are identified and knowledge gaps indicated.
RESUMEN
To ensure sufficient food supply worldwide, plants are treated with pesticides to provide protection against pathogens and pests. Herbicides are the most commonly utilised pesticides, used to reduce the growth of weeds. However, their long-term use has resulted in the emergence of herbicide-resistant biotypes in many weed species. Cornflower (Centaurea cyanus L., Asteraceae) is one of these plants, whose biotypes resistant to herbicides from the group of acetolactate synthase (ALS) inhibitors have begun to emerge in recent years. Some plants, although undesirable in crops and considered as weeds, are of great importance in phytomedicine and food production, and characterised by a high content of health-promoting substances, including antioxidants. Our study aimed to investigate how the acquisition of herbicide resistance affects the health-promoting properties of plants on the example of cornflower, as well as how they are affected by herbicide treatment. To this end, we analysed non-anthocyanin polyphenols and antioxidant capacity in flowers of C. cyanus from herbicide-resistant and susceptible biotypes. Our results indicated significant compositional changes associated with an increase in the content of substances and activities that have health-promoting properties. High antioxidant activity and higher total phenolic and flavonoid compounds as well as reducing power were observed in resistant biotypes. The latter one increased additionally after herbicide treatment which might also suggest their role in the resistance acquisition mechanism. Overall, these results show that the herbicide resistance development, although unfavourable to crop production, may paradoxically have very positive effects for medicinal plants such as cornflower.
Asunto(s)
Resistencia a los Herbicidas , Herbicidas , Herbicidas/farmacología , Malezas , FloresRESUMEN
BACKGROUND: The continuous use of the herbicides contributes to the emergence of the resistant populations of numerous weed species that are tolerant to multiple herbicides with different modes of action (multiple resistance) which is provided by non-target-site resistance mechanisms. In this study, we addressed the question of rapid acquisition of herbicide resistance to pinoxaden (acetyl CoA carboxylase inhibitor) in Apera spica-venti, which endangers winter cereal crops and has high adaptation capabilities to inhabit many rural locations. To this end, de novo transcriptome of Apera spica-venti was assembled and RNA-sequencing analysis of plants resistant and susceptible to pinoxaden treated with this herbicide was performed. RESULTS: The obtained data showed that the prime candidate genes responsible for herbicide resistance were those encoding 3-ketoacyl-CoA synthase 12-like, UDP-glycosyltransferases (UGT) including UGT75K6, UGT75E2, UGT83A1-like, and glutathione S-transferases (GSTs) such as GSTU1 and GSTU6. Also, such highly accelerated herbicide resistance emergence may result from the enhanced constitutive expression of a wide range of genes involved in detoxification already before herbicide treatment and may also influence response to biotic stresses, which was assumed by the detection of expression changes in genes encoding defence-related proteins, including receptor kinase-like Xa21. Moreover, alterations in the expression of genes associated with methylation in non-treated herbicide-resistant populations were identified. CONCLUSION: The obtained results indicated genes that may be involved in herbicide resistance. Moreover, they provide valuable insight into the possible effect of resistance on the weed interaction with the other stresses by indicating pathways associated with both abiotic and biotic stresses. © 2023 Society of Chemical Industry.