Biopreparations for the decomposition of crop residues.

Recently, there has been growing interest in biopreparations that intensify the decomposition of crop residues. These preparations can promote nutrient cycling and soil fertility, ultimately supporting healthy plant growth and increasing agricultural productivity. However, the development and commercialization of biopreparations poses unique challenges. Producers of biopreparations struggle to develop highly effective preparations, which then face regulatory hurdles and must win market acceptance. This literature review provides up-to-date data on microbial preparations available commercially on the European market, along with information on current relevant regulations. Challenges for the development and commercialization of new biopreparations are also discussed. The development and commercialization of biopreparations require a comprehensive approach that addresses the complex interplay of microbial and environmental factors. The need for more specific regulations on biopreparations for decomposing crop residues, clearer instructions on their use, and further research on the overall impact of biopreparations on the soil metabolome and optimal conditions for their application were indicated. Moreover, manufacturers should prioritize the development of high-quality products that meet the needs of farmers and address concerns about environmental impact and public acceptance.

Chitosan as an Antimicrobial, Anti-Insect, and Growth-Promoting Agent for Potato (Solanum tuberosum L.) Plants.

A growing trend in plant protection is replacing chemical preparations with environmentally friendly biological compositions. Chitosan, due to its biocompatibility, biodegradability, and bioactivity, is an effective agent against plant diseases. The purpose of the study was to evaluate chitosan as a potential biopesticide for potato plants. Three variants of chitosan were tested: high (310-375 kDa, >75% deacetylated), medium (190-310 kDa, 75-85% deacetylated), and low (50-190 kDa, 75-85% deacetylated) molecular weight. The chitosan variants were dissolved in lactic and succinic acids and tested for antibacterial and antifungal properties against eight strains of mould and two strains of bacteria responsible for potato diseases. The possible cytotoxicity of chitosan was evaluated against different cell lines: insect Sf-9, human keratinocyte HaCaT, and human colon carcinoma Caco-2. The bioprotective activities of the chitosan were also evaluated in situ on potato tubers. Chitosan inhibited the growth of almost all the selected phytopathogens. The most active was medium molecular chitosan in lactic acid. This formula was characterized by low toxicity towards human cells and high toxicity towards Sf-9 cells. It was also found to have positive effects on the growth of stems and roots, gas exchange, and chlorophyll index in potato plants. Selected chitosan formulation was proposed as a functional biopesticide for potato protection against phytopathogens.

Valorization of sorghum ash with digestate and biopreparations in the development biomass of plants in a closed production system of energy.

Replacing chemical fertilizers with non-toxic waste that meet all fertilizing purposes, including ash from plant biomass and their management is becoming the important goal of sustainable agriculture concerning energy plants production in a closed system. This study aims to explore a novel strategy for utilizing natural sorghum ash together with digestate and ecological compounds, to replace synthetic fertilizers, for the energy plant development improvement and thus reduction of the environment pollution. Sorghum, as an energy plant, cultivated in low quality sandy and podzolic soils, in Central and North Poland climate, was fertilized with different doses of YaraMila Complex, a synthetic fertilizer (0, 150, 300 kg ha-1 Each dose was supplemented with different amounts of sorghum ash (0.5, 1, 2 and 4 t ha-1), used alone or with addition of APOL-HUMUS (soil improver; 10 L ha-1), biogas plant digestate (30 m3 ha-1) and Stymjod (nano-organic leaf fertilizer; 5 L ha-1). Added to each YaraMila Complex dose, the applied ash amounts (optimally 2-4 t ha-1), increased growth of plants, crop biomass, index of chlorophyll content, net photosynthesis, transpiration, stomatal conductance, content of intercellular CO2, activity of acid and alkaline phosphatase, RNase and dehydrogenase and energy properties. Sorghum ash used with the lesser YaraMila Complex doses of 0 or 150 kg ha-1 caused the enhanced growth of plants more than the doubled YaraMila Complex amounts applied alone (150 or 300 kg ha-1, correspondingly). Additionally, applied biogas plant digestate, APOL-HUMUS and Stymjod further increased the plant growth. This indicates that the application of natural sorghum ash accelerates energy plant development, can reduce by half the recommended synthetic fertilizer doses on poor and marginal soil and enables the cultivation of sorghum in a closed production cycle.

Metabolite Formation by Fungal Pathogens of Potatoes (Solanum tuberosum L.) in the Presence of Bioprotective Agents.

The potato is a crop of global importance for the food industry. This is why effective protection against pathogens is so important. Fungi as potato pathogens are responsible for plant diseases and a significant reduction in yields, as well as for the formation of mycotoxins. This study focuses on the effect of three natural biocides, yeast Metschnikowia pulcherrima, lactic acid bacteria Lactiplantibacillus plantarum, and aqueous garlic extract, on the improvement of the physiology of planted potato tubers and the reduction in mycotoxin formation. The secondary metabolites produced by the fungal pathogens of genera Fusarium, Alternaria, Colletotrichum, Rhizoctonia, and Phoma in the presence of these biocontrol agents were compared to profiles obtained from contaminated potatoes. Analysis of liquid chromatography coupled with tandem mass spectrometry data showed the presence of 68 secondary metabolites, including the mycotoxins: alternariol, alternariol methyl ether, altertoxin-I, aurofusarin, beauvericin, diacetoxyscirpenol, enniatin B, and sterigmatocystin. The studies showed that the applied biocontrol agents had a positive effect on the physiological parameters of potatoes (including root growth, stem growth, gas exchange, and chlorophyll content index) and on the reduction in the production of mycotoxins and other secondary metabolites by Fusarium, Alternaria, and Phoma.

Volatile Organic Compounds and Physiological Parameters as Markers of Potato (Solanum tuberosum L.) Infection with Phytopathogens.

The feasibility of early disease detection in potato seeds storage monitoring of volatile organic compounds (VOCs) and plant physiological markers was evaluated using 10 fungal and bacterial pathogens of potato in laboratory-scale experiments. Data analysis of HS-SPME-GC-MS revealed 130 compounds released from infected potatoes, including sesquiterpenes, dimethyl disulfide, 1,2,4-trimethylbenzene, 2,6,11-trimethyldodecane, benzothiazole, 3-octanol, and 2-butanol, which may have been associated with the activity of Fusarium sambucinum, Alternaria tenuissima and Pectobacterium carotovorum. In turn, acetic acid was detected in all infected samples. The criteria of selection for volatiles for possible use as incipient disease indicators were discussed in terms of potato physiology. The established physiological markers proved to demonstrate a negative effect of phytopathogens infecting seed potatoes not only on the kinetics of stem and root growth and the development of the entire root system, but also on gas exchange, chlorophyll content in leaves, and yield. The negative effect of phytopathogens on plant growth was dependent on the time of planting after infection. The research also showed different usefulness of VOCs and physiological markers as the indicators of the toxic effect of inoculated phytopathogens at different stages of plant development and their individual organs.

Maximal Efficiency of PSII as a Marker of Sorghum Development Fertilized With Waste From a Biomass Biodigestion to Methane.

The aim of experiments was to investigate a maximal efficiency of PSII, as a marker indicating growth, vigor, energetic value and physiological activity of sorghum fertilized with wastes from a biomass biodigestion to methane in a distillery integrated with a biogas plant using corn grains as substrate. The sorghum plants grown outdoor in different climate and in pots and in field were fertilized with different doses of the waste or Apol-humus - a soil improver and Stymjod - a nano-organic-mineral fertilizer. The maximal efficiency of PSII, in comparison with plant growth and health, chlorophyll content, gas exchange, activity of selected enzymes, element content in leaves and energetic value were studied. The wastes applied to soil resulted in increased maximal efficiency of PSII and the doses of 30 m3 ha-1 and 40-50 m3 ha-1 of the non-centrifuged and centrifuged ones, respectively, were most efficient. This enhancement was associated with the increased kinetics of plant growth, their health, fresh and dry biomass and physiological activity of plants as evidenced by activity of acid and alkaline phosphatase, RNase and dehydrogenase, as well as by gas exchange: net photosynthesis, transpiration, stomatal conductance, intercellular CO2 concentration and index of chlorophyll content in leaves. The fertilization with Apol-humus and Stymjod additionally increased maximal photochemical efficiency of PSII and plant development, biomass yield and physiological activity. The results indicate that waste from a biomass biodigestion to methane can be used as a natural fertilizer in sorghum crops and this ensures their recycling and environmental protection. The measurement values of maximal efficiency of PSII were proportionally to the vigor, growth and physiological activity of the plants. The obtained results indicate that the maximal efficiency of PSII in sorghum plants is a non-destructive method for defining the degree of growth and may be used as a marker of plant vigor and health, development and physiological activity expressed by gas exchange and activity of selected enzymes.

High efficiency stratification of apple cultivar Ligol seed dormancy by phytohormones, heat shock and pulsed radio frequency.

The aim of the study was to improve the effect of stratification of apple "Ligol" seeds by application of selected compounds, phytohormones, and physical methods For this purpose the seeds were stratified at 3°C in distilled water or in the presence of potassium nitrate (KNO3), ethephon (ET), carbon monoxide (CO), hydrogen peroxide (H2O2), a mixture of KNO3, ET, CO, H2O2, gibberellins (GA3), 6-benzylaminopurine (BAP), jasmonic acid (JA), salicylic acid (SA) and a mixture of SA, GA3, BAP, JA, nitric oxide (NO), hydrogen chloride (HCL). Arranged protocols included various durations and combinations of selected compounds and phytohormones as well as laser and red light, heat shock - 2h heat shock (45°C) and Pulsed Radio Frequency (PRF) were investigated by germination tests and the activity of selected enzymes, gas exchange and index of chlorophyll in leaves. The obtained results showed the possibility to shorten more effectively the time of the apple 'Ligol' dormancy removal by treatments of the stratified seeds at 3°C with different biological and physical methods Selected compounds and phytohormones acted collectively as a regulatory complex controlling the course of release from dormancy. Physical methods (PRF and heat shock) additionally contributed to dormancy breakage. Duration of phytohormones or compounds impacts during stratification should be prolonged to minimum 7days to assure more balanced conditions of the regulatory complex for the acceleration of dormancy a removal. The most beneficial results were obtained after seed stratification for 7days on filter paper moistened in KNO3+Etephon+CO+H2O2 at 3°C, and then on filter paper moistened in phytohormones (GA3+BAP+JA) till the end of seed germination (3°C). The application of this protocol could be a very useful tool in a shortening the apple breeding cycle since the period of removing dormancy was reduced by 38days in comparison to stratified in water. PRF has also the additive role in breaking dormancy of apple 'Ligol' seed. Positive effects of compounds and phytohormones applied during stratification remarkably accelerated the growth of developed from them seedlings. Further research is needed to optimize stratification methods with appropriate contents and concentrations of compounds and phytohormones combined with PRF exposure.