The feasibility of utilising spent mushroom substrates (SMSs) as a growing medium component for Pleurotus ostreatus cultivation was investigated. P. ostreatus was cultivated on traditional wheat straw (control) and wheat straw substrate supplemented with SMSs from Pholiota nameko (N-SMS), Hypsizygus marmoreus (M-SMS), and Hericium erinaceus (E-SMS) in varying supplementation rates (10%, 20%, and 30%). The yield, biological efficiency (BE), dry matter, and protein content of P. ostreatus fruiting bodies grown on ten substrates were evaluated. Significant differences in yield, BE, protein content, and dry matter of P. ostreatus were found among the studied substrates. The highest yield was recorded in 20% E-SMS (254.33 g), 20% N-SMS (253.43 g), and 10% E-SMS (251.67 g). The biological efficiency ranged from 66.48% (30% M-SMS) to 72.67% (20% E-SMS) and followed a similar trend to yield. The highest protein content was recorded in 30% M-SMS (29.93 g∙100 g dry weight−1). The highest dry matter of P. ostreatus was noticed in 30% of M-SMS (23.74 g) and 10% of M-SMS (23.06 g). Therefore, the spent mushroom substrates of Ph. nameko, H. marmoreus, and H. erinaceus could be used as a potential, low-cost sustainable alternative (10–30%) and as a renewable component of traditional growing media for P. ostreatus cultivation.

The performance of autumn and spring-planted strawberry cv. ‘Elsanta’ in peat and peat supplemented with fresh spent mushroom substrate (SMS) of Agaricus bisporus, Lentinus edodes, and Pleurotus ostreatus in 15% and 25% was evaluated. The morphological and yield parameters, dry matter distribution, uptake, and partitioning of macro- and micronutrients were studied. The experiment was carried out during 2020–2021 in an unheated tunnel and was laid out in a randomised complete block design in five replicates. The study aimed to deliver greater insight into utilising fresh SMS as a sustainable substitute to peat. The shoot and root length, leaf number, crown diameter, plant dry weight, and marketable yields were superior in SMS-based substrates in autumn planting. The nutrient uptake varied among substrates and planting seasons, where higher plant nutrient uptake was noticed in SMS-based substrates. Nutrient partitioning among leaves, crowns, and roots was dynamic. The N, P, K, and Mn were mainly recovered in leaves. While Mg was almost equally partitioned among plant organs. The higher amounts of Na, Zn, and Cu were found in crowns. The greater accumulation of Ca and Fe in roots was evident. Correlation indicated that plant macro- and micronutrients had both positive and negative interactions. Overall, the superior morphological and yield performances of cv. ‘Elsanta’ were more noticeable in SMSs than in peat in autumn-planted strawberries.

The ability of plant resistance inducers to provide protection against viral diseases is one of their main advantages over conventional pesticides. In the case of viral diseases that cannot be controlled directly with pesticides, insecticides are used to control the vectors of viruses. However, the effectiveness of such treatments is strictly dependent on the time of application. The plant response to the application of systemic acquired resistance (SAR) inducers, as a result of the stimulating action of these substances, does not depend on the time of application as it triggers the plant’s natural defence mechanism. The best-recognised substance showing SAR inducer activity is acibenzolar-S-methyl ester (ASM, BTH). As its activity against different plant pathogens of crops has been well documented, the current research is concentrated on the search for novel substances of the type. The tested substance, N-methoxy-N-methylbenzo(1,2,3)thiadiazole-7-carboxamide (BTHWA), is an amide derivative of benzothiadiazole, showing plant resistance-inducing activity. This article presents the activity of BTHWA that has led to increased resistance of zucchini (Cucurbita pepo convar. giromontiina) towards viral infections. In addition, since the occurrence of the fungal pathogen, powdery mildew, was also observed during the two-year field experiments, the activity of BTHWA related to the reduction of infection with this fungus was also investigated. The substance was applied in two different variants either four or eight times, over the whole vegetation season. Surprisingly, the variant of four applications performed at the beginning of the vegetation season proved more effective in protection against viruses and fungus. A possible explanation may be the occurrence of the growth–immunity trade-off phenomenon that is known in the literature. Disturbance in plant metabolism resulting from eight applications may lead to lower yields of plants treated with SAR inducers. Perhaps such overstimulation of the plants we treated eight times may not have brought the optimum increase in plant resistance.

The present study aimed to evaluate fresh spent mushroom substrate (SMS) as a growing medium in soilless strawberry cv. ‘Honeoye’ production. Fresh SMS after commercial production of Agaricus bisporus, Lentinus edodes, and Pleurotus ostreatus was used as a peat substitute in 15 and 25% (v/v), for strawberry cultivation in an unheated plastic tunnel. In the experiment, seven different substrates were studied, including peat (100%) as control and six substrate combinations (prepared by mixing SMSs with peat). The study was carried out in a randomized complete block design in five replicates. The results indicated that the electrical conductivity (EC), pH, and nutrient content varied among the studied substrates. The experiment also demonstrated that the substrates significantly influenced strawberry yield, leaf area, and fresh and dry plant weights. However, no significant differences were observed for selected photosynthetic parameters (Fv/Fm, Fv/F0, and PIabs) and Normalized Difference Vegetation Index (NDVI) values among the evaluated substrates. Differences were recorded for the Photochemical Reflectance Index (PRI) and Modified Chlorophyll Absorption in Reflectance Index (MCARI) values. The present investigation revealed that fresh SMSs can be an effective and inexpensive peat substitute in 15 and 25% (v/v). Therefore, such easy and immediate utilisation of SMSs could overcome associated disposal problems.

Oak powdery mildew caused by Erysiphe alphitoides (Griffon and Maubl.; U. Braun & S. Takam.) is a common disease in European forests. One of the most susceptible species is the pedunculate oak (Quercus robur L.). Presently, a few methods are available to control powdery mildew, e.g., the use of fungicides (e.g., based on citric acid), antagonistic fungi or bacteria, chemical treatments (e.g., sulphur, potassium bicarbonate) or genetic resistance. In our study, we aimed to check the effects of using chitosan derivatives and novel active substances inducing the plants’ natural resistance: benzodiathiadiazole (both in neutral and salt form). 84 pedunculate oak seedlings were subjected to the experiment in three treatment variants (plus positive and negative controls). The plants were treated with active substances and inoculated with E. alphitoides. Although the powdery mildew symptoms appeared in all variants, they were manifested mainly by the mycelium in the form of small spots. The experiment indicated that the highest limitation of powdery mildew mycelium was achieved by applying N-methyl-N-methoxyamide-7-carboxybenzo(1,2,3)thiadiazole (BTHWA). The application of BTHWA reduced disease development by 88.9% when compared to the effects of the other variants.