Use of SCAR-PCR in diagnostics of stem base pathogens of the Rhizoctonia and Oculimacula genus

The aim of the paper is to compare the efficacy of SCAR-PCR assay and conventional diagnostic technique (visual assessment, isolation on PDA medium) in the identification of fungi from the genera Rhizoctonia and Oculimacula from winter triticale, rye, and barley during the shooting stage. The usefulness of molecular diagnosis of fungal pathogens in crop plants has been demonstrated. The application of SCAR- -PCR assay allowed early detection of the following pathogens: O. yallundae, O. acuformis, R. cerealis and R. solani, in plant tissues. This method was particularly effective in detection of R. solani. The research showed the usefulness of PCR markers for early detection of fungal pathogens, even if symptoms were not visible. Using the PCR technique, especially in combination with conventional methods, substantially increases the precision and effectiveness of disease diagnostics

Binucleate Rhizoctonia Strain: A Potential Biocontrol Agent in Wheat Production

As a polyphagous organism, Rhizoctonia is one of the most infectious soil-borne pathogens for many plant species. To reduce this threat to plants and hence provide good quality plant products for the end-user, it is crucial to develop sophisticated and environmental friendly plant protection methods. One such method is biological control using beneficial agents, e.g., microorganisms such as bacteria and fungi, but also mites or insects. To investigate the potential of this control, we present here a study involving AG B0 (BNR), which is a binucleate, non-pathogenic Rhizoctonia as a control against pathogens from the same genus, namely, Rhizoctonia cerealis (AG DI) and Rhizoctonia solani (AG5 and AG 1IC). This is novel because the relationship between plant-pathogen and plant-non-pathogen interactions has received only limited attention. Once the relative activities of the various plant defense mechanisms and the overall plant conditions were taken into account, the non-pathogenic binucleate strain was found to lower the impact of the pathogenic strain. We conclude that the response of plant genotype within the context of the protective activity of the non-pathogenic Rhizoctonia is race-specific. The research showed the ability to successfully protect wheat plants from R. cerealis negative impact, as well as in some cases from R. solani

Effects of farming system, chemical control, fertilizer and sowing density on sharp eyespot and Rhizoctonia spp. in winter wheat

Effects of agronomic practices on the occurrence of sharp eyespot and Rhizoctonia spp. in winter wheat were determined in two field experiments. In Experiment 1, in the village of Osiny, a comparison was made of disease in different farming systems. The farming systems were: organic, integrated, conventional, and monoculture. In Experiment 2, in the village of Mochełek, the effects of different chemical controls (no treatment, herbicide, herbicide + fungicide), mineral fertilizer doses (147 and 221 kg/ha NPK) and sowing densities (400 and 600 grains/m2) on the occurrence of sharp eyespot were compared in wheat grown in short-term monoculture. There was considerably more sharp eyespot in 2007 (disease index 1.63-29.5%) than in other years. Significant effects of the treatments were mostly noted at the milk ripe growth stage. The fewest sharp eyespot symptoms were seen in the integrated farming system. The most sharp eyespot symptoms were seen in the conventional and organic systems. There was a tendency for an increased intensity of symptoms in successive wheat-growing years of short-term monoculture. The application of pesticides showed no clear effect on the occurrence of sharp eyespot. The herbicide resulted in increased or decreased disease intensity depending on the cultivation year and the date of observation. Fungicide application did not decrease infection. Without chemical control, more symptoms were observed at the lower NPK rate. There were more symptoms at the higher sowing density. Stems with sharp eyespot symptoms were mostly infected by Rhizoctonia cerealis, and less frequently by R. solani. Binucleate Rhizoctonia spp., which could not be identified to species using polymerase chain reaction (PCR) techniques, were also recorded. Two R. zeae isolates were also obtained from stems with disease symptoms in Mochełek. R. solani was more often isolated from roots or stems with symptoms of true eyespot or fusarium foot rot. Most isolates of Rhizoctonia spp. were obtained at the milk ripe stage. A wheat-growing system and chemical control did not greatly affect the frequency of Rhizoctonia spp

Binucleate <i>Rhizoctonia</i> Strain: A Potential Biocontrol Agent in Wheat Production

As a polyphagous organism, Rhizoctonia is one of the most infectious soil-borne pathogens for many plant species. To reduce this threat to plants and hence provide good quality plant products for the end-user, it is crucial to develop sophisticated and environmental friendly plant protection methods. One such method is biological control using beneficial agents, e.g., microorganisms such as bacteria and fungi, but also mites or insects. To investigate the potential of this control, we present here a study involving AG B0 (BNR), which is a binucleate, non-pathogenic Rhizoctonia as a control against pathogens from the same genus, namely, Rhizoctonia cerealis (AG DI) and Rhizoctonia solani (AG5 and AG 1IC). This is novel because the relationship between plant-pathogen and plant-non-pathogen interactions has received only limited attention. Once the relative activities of the various plant defense mechanisms and the overall plant conditions were taken into account, the non-pathogenic binucleate strain was found to lower the impact of the pathogenic strain. We conclude that the response of plant genotype within the context of the protective activity of the non-pathogenic Rhizoctonia is race-specific. The research showed the ability to successfully protect wheat plants from R. cerealis negative impact, as well as in some cases from R. solani

Response of Indian Dwarf Wheat and Persian Wheat to Sowing Density and Hydrothermal Conditions of the Growing Seasons

The need for foods with high nutritional value has led to the rediscovery of ancient wheat species Triticum sphaerococcum and T. persicum as raw materials with valuable consumption properties, but their reintroduction requires assessment of their productivity under different agricultural practices. The field experiments were carried out for three years (2018–2020) to test the hypothesis that the sowing density of T. sphaerococcum and T. persicum (400, 500 and 600 no m−2) will affect their agronomic traits, yield and occurrence of diseases, but the response will depend on the hydrothermal conditions of the growing seasons. In this study, a significant correlation of the grain yield with the amount of precipitation in tillering, and from booting to the beginning of fruit development was demonstrated. The sowing density of T. sphaerococcum had an impact on the grain yield only under moderate drought stress during the growing season (2019), when the highest yield was obtained at a sowing density of 600 m−2. In 2019, the most favorable sowing density was also the highest for T. persicum. In the year with the lowest amount of rainfall during the growing season (2018), the yield of T. persicum was the highest in the lowest sowing density. At the shooting stage, a greater intensity of powdery mildew was observed on T. persicum, especially with higher sowing densities. Increasing the sowing density also increased the occurrence of root rot symptoms in both wheat species in the year that favored the occurrence of this disease (2018). It can be concluded that in the integrated low-input cultivation of T. sphaerococcum and T. persicum, it is justified to use a sowing density of 600 pcs. m−2, in an agroclimatic zone with moderate droughts during the growing season

Screening Winter Wheat Genotypes for Resistance Traits against <i>Rhizoctonia cerealis</i> and <i>Rhizoctonia solani</i> Infection

Rhizoctonia cerealis and Rhizoctonia solani are considered to be among the most harmful soil-borne pathogens for crop plants globally. The lack of effective protection and the requirement to minimize the use of chemical pesticides necessitate the need to develop alternative protective methods. One such method is resistance breeding against biotic and abiotic stresses. Here, we present studies on the presence of resistance traits in winter wheat genotypes that evaluate the plants’ resistance to the above two pathogens, in both field and laboratory environments. In the field environment, the incidence and severity of sharp eyespot were studied using 132 winter wheat cultivars, where random samples at the BBCH 75–77 were collected for analysis. The degree of the intensity of sharp eyespot was determined, applying the 0–4° scale. The susceptibility of the 132 cultivars of winter wheat to R. cerealis (AG-D subgroup I) and R. solani (AG-5) was also studied under laboratory conditions. In the laboratory, test pieces of potato dextrose agar colonized by the test isolates were placed onto filter paper soaked with distilled water and then placed into Petri dish. Infection on the roots, coleoptiles and leaves was then assessed after 15 days for R. cerealis and after 10 days for R. solani. None of the tested winter wheat genotypes were found to be asymptomatic to the pathogens. A moderate susceptibility was observed for such genotypes as Anthus, Baryton, Bellenus, Borderland Benatka, Blonde, Cubus, Estero, and Flairway. However, the classification of those associated with moderate susceptibility in laboratory tests resulted in severe symptoms in field tests. Hence, field experiments provide the most reliable measurements to determine the effects of pathogens on the plants

Effects of Eco-Friendly Product Application and Sustainable Agricultural Management Practices on Soil Properties and Phytosanitary Condition of Winter Wheat Crops

Despite the eco-political difficulties that accompany the application of principles of the European Green Deal policy on agriculture in the current world crisis, the need of their implementation seems to be absolutely necessary. The practices recommended within the sustainable agriculture strategy include replacing traditional fertilizers and pesticides with eco-friendly preparations and optimizing the management of biomass produced on farms. The aim of the research was to determine the effect of eco-friendly preparations application combined with straw incorporation on the chemical and microbiological soil parameters and plant sanitary status of winter wheat. The soil analyses included the determination of total organic carbon (TOC) and total nitrogen (TN) content; mineral nitrogen (MN), phosphorus (P), potassium (K), and magnesium (Mg) content, and the pH value. The number of soil bacteria (B), actinobacteria (A), fungi (F), and the total number of microorganisms (TNM) were also analyzed. The application of Effective Microorganisms resulted in an increase in TOC and TN concentration. The influence of biostimulator Asahi was diversified. The beneficial effect of straw on TOC, TN, and K content and microbial growth was also observed. Despite a number of limitations, the potential benefits of application of eco-friendly preparations provide ample reasons to continue experiments with their use

Effects of Eco-Friendly Product Application and Sustainable Agricultural Management Practices on Soil Properties and Phytosanitary Condition of Winter Wheat Crops

Despite the eco-political difficulties that accompany the application of principles of the European Green Deal policy on agriculture in the current world crisis, the need of their implementation seems to be absolutely necessary. The practices recommended within the sustainable agriculture strategy include replacing traditional fertilizers and pesticides with eco-friendly preparations and optimizing the management of biomass produced on farms. The aim of the research was to determine the effect of eco-friendly preparations application combined with straw incorporation on the chemical and microbiological soil parameters and plant sanitary status of winter wheat. The soil analyses included the determination of total organic carbon (TOC) and total nitrogen (TN) content; mineral nitrogen (MN), phosphorus (P), potassium (K), and magnesium (Mg) content, and the pH value. The number of soil bacteria (B), actinobacteria (A), fungi (F), and the total number of microorganisms (TNM) were also analyzed. The application of Effective Microorganisms resulted in an increase in TOC and TN concentration. The influence of biostimulator Asahi was diversified. The beneficial effect of straw on TOC, TN, and K content and microbial growth was also observed. Despite a number of limitations, the potential benefits of application of eco-friendly preparations provide ample reasons to continue experiments with their use