No abstract

No abstract

Fungal pathogens cause significant yield losses of many important crops worldwide. They are commonly controlled with fungicides which may have negative impact on human health and the environment. A more sustainable plant protection can be based on carbohydrate biopolymers because they are biodegradable and may act as antifungal compounds, effective elicitors or carriers of active ingredients. We reviewed recent applications of three common polysaccharides (chitosan, alginate and cellulose) to crop protection against pathogenic fungi. We distinguished treatments dedicated for seed sowing material, field applications and coating of harvested fruits and vegetables. All reviewed biopolymers were used in the three types of treatments, therefore they proved to be versatile resources for development of plant protection products. Antifungal activity of the obtained polymer formulations and coatings is often enhanced by addition of biocontrol microorganisms, preservatives, plant extracts and essential oils. Carbohydrate polymers can also be used for controlled-release of pesticides. Rapid development of nanotechnology resulted in creating new promising methods of crop protection using nanoparticles, nano-/micro-carriers and electrospun nanofibers. To summarize this review we outline advantages and disadvantages of using carbohydrate biopolymers in plant protection.

Soybean [Glycine max (L.) Merrill] plants are potential hosts for different pathogens. Soil-borne diseases, caused by pathogenic fungi, are considered to be the main reason for the loss of soybean yields worldwide. The aim of the research was to isolate fungi inhabiting underground parts of soybean in order to identify potential pathogens present in south-east Poland. Research material comprised of seven soybean cultivars grown in field in 2017-2019. Samples collected in three subsequent vegetative seasons constituted soybean plants with disease symptoms on cotyledons, stems and roots. Fragments of the infected plant tissues were subjected to mycological analysis. A total of 1692 pure fungal isolates were obtained from the sampled plants and almost 80% of these isolates were assigned to Fusarium genus. Among Fusarium spp. isolates, the most frequently detected species was F. oxysporum (71.3%). Other detected Fusarium species included: F. graminearum, F. culmorum, F. avenaceum, F. poae, F. solani (syn. Neocosmospora solani), F. sporotrichioides and F. fujikuroi. Other fungi accounted for approx. 19% of the obtained isolates and their main representatives were: Alternaria alternata, Trichoderma sp., Rhizoctonia solani, Mucor sp., Cladosporium sp. and Rhizopus sp. Comparison of these results with published data from other regions of Poland shows differences in prevalence of different species of soil-borne fungi.

Growing resistant cultivars is the best method of protecting the crops against Potato virus Y (PVY). There are a few sources of PVY resistance/tolerance in tobacco acquired through mass selection, X-ray induced mutagenesis and introgressions from wild Nicotiana species. Here, we compare major sources of PVY resistance/tolerance in inoculation tests using ten PVY isolates collected in Central Europe (Poland and Germany) and differing with their virulence. The diversity of collected isolates was confirmed by DAS-ELISA tests and two PCR assays targeting the most common recombination sites in the PVY genome. We used these isolates in inoculation tests on five resistant cultivars ‘V.SCR’, ‘PBD6’, ‘TN86’, ‘VAM’, ‘Wiślica’, a tolerant breeding line ‘BPA’ and four susceptible cultivars ‘BP-210’, ‘K326’, ‘NC95’, ‘Samsun H’. None of the tested cultivars/breeding lines showed universal resistance against all ten isolates. However, ‘VAM’ and ‘Wiślica’ appeared to be the most effective sources, as they showed no symptoms and gave negative DAS-ELISA tests for four out of ten tested PVY isolates. In contrast, tolerance of the breeding line ‘BPA’ was effective against all tested isolates, because inoculation did not lead to development of full disease symptoms in that breeding line.