Organic farming relies on sustainable, eco-friendly practices that promote soil health, biodiversity, and climate resilience. Bioresources—derived from plants, animals, and microorganisms—are pivotal in replacing synthetic inputs with natural alternatives. This review presents an integrated analysis of bioresources, highlighting their classification, functionality, and role in organic systems through biofertilizers, biopesticides, organic amendments, and bioenergy. Despite their potential, challenges such as knowledge gaps, limited scalability, and technical constraints hinder their widespread adoption. The review emphasizes the ecological, economic, and social benefits of bioresource integration while identifying critical barriers and proposing strategic directions for research, policy, and practice. By addressing these gaps, bioresources can enhance nutrient cycling, pest management, and soil regeneration, offering a viable path toward sustainable agriculture. This synthesis supports the development of context-specific, circular, and resilient organic farming systems that align with global sustainability goals.

Nitrogen (N) fertilizer application is one of the most crucial agronomic management practices for increasing grain yield in maize crops. However, the long application may adversely affect soil quality. For achieving sustainable agricultural production, the current research set out to evaluate the short-term effects of the addition of zeolite as a soil amendment and N fertilization on the maize growth, yield, quality, N- and water-use efficiency in three locations (Athens, Messolonghi, and Karditsa) in Greece. Each experiment set up during the spring–summer 2024 cultivation period was laid out in a split-plot design with three main plots (Zeolite treatments: 0, 5, and 7.5 t ha⁻¹) and four sub-plots (N fertilization treatments: 0, 100, 150, and 200 kg N ha⁻¹). The results revealed that increasing the zeolite application rate from 0 to 7.5 t ha⁻¹ led to a significant increase in grain yield, with the highest value (13.46, 12.46, and 14.83 t ha⁻¹ in Athens, Messolonghi, and Karditsa, respectively) observed at 7.5 t ha⁻¹. In the same manner, the increasing inorganic N fertilization rate from 0 to 200 kg N ha⁻¹, also increased the grain yield. In general, most of the soil properties (soil organic matter, soil total nitrogen, total porosity, soil moisture content, and infiltration rate), root and shoot growth (root length density, plant height, leaf area index and dry weight), N content and uptake of the grains, and aerial biomass, as well as, thousand kernel weight, N harvest index (NHI), and water use efficiency (WUE), were positively affected by both of the examined factors. In conclusion, this study proved that the increasing rates of zeolite as a soil amendment and N fertilization up to a rate of 7.5 t ha⁻¹ and 200 kg N ha⁻¹, respectively, improved soil properties, promoted plant development, and increased grain yield, grain and biomass N uptake, NHI, and WUE of the maize crop cultivated in clay–loam soils and under Mediterranean conditions, where the experimental trials set up.

The literature suggests that nitrogen (N) fertilization increases yield in soybean. This study aimed to investigate the effects of N fertilization on: (i) The performance of soybean, and (ii) the weed flora. A two-year field experiment was carried out in Agrinio, Western Greece. The experiment was set up in a randomized complete block design, with four organic fertilizer treatments and six replications. The four treatments included 0 kg N ha⁻¹ (N0/unfertilized control) and the application of 80 kg N ha⁻¹, 100 kg N ha⁻¹, and 120 kg N ha⁻¹. The application of 120 N kg ha⁻¹ resulted in the most notable increment of plant height (22.6–24%), biomass (10–13%), LAI values (14–17%), and yield (10–12%) compared to the N0. Compared to the N0, total weed biomass was increased by 26–32%, 34–49%, and 55–57% in N80, N100, and N120, respectively. The values of the H (Shannon), Dmg (Margalef), and J (Pielou) indices were unaffected by the fertilization, hence they did not affect weed biodiversity. CRI (crop resistance index), on the contrary, was negatively affected by N fertilization and was significantly reduced. Overall, our results indicate that the application of 80 kg N ha⁻¹ is more efficient, can effectively improve the soybean performance, and enhance its yield.

The most common and damaging plant parasitic nematodes are root-knot nematodes (RNK). Although hemp has been clearly infected by RNK, little information is available regarding the extent of the damage and losses caused. In addition, no information is available concerning hemp seed extracts’ activity against RNK. In the current research, a greenhouse experiment was developed to evaluate the infection effect of five RKN species (Meloidogyne javanica, M. incognita, M. arenaria, M. hapla, and M. luci) in nine industrial hemp varieties (Fedora 17, Ferimon 12, Futura 75, Santhica 27, Santhica 70, KC Dora, KC Zuzana, Zenit, and USO 31), as was a laboratory experiment to evaluate the nematicidal activity of aqueous and water extracts of hemp seeds against second-stage juveniles (J2s) of M. javanica. The results revealed that the five evaluated Meloidogyne species were pathogenic to hemp plants. The lowest shoot weights were recorded in plants that were inoculated with M. javanica and M. luci (4.65 and 4.53 g, respectively). As for the root system, the most severe damage of the roots was detected in M. incognita-infected plants, presenting the lowest root weight (1.72 g). Regarding hemp varieties, the most susceptible were USO 31, Fedora 17, Ferimon 12, and Zenit, while Futura 75 hosted the lowest nematode numbers, including the lowest values of females per gram of root (10.66), number of egg masses per gram of root (4.70), and fecundity (33.68 eggs per egg mass). Moreover, this research showed that aqueous and ethanolic hemp seed extracts can control M. javanica. After 24, 48, 72, and 96 h of exposure to high concentrations (250–2000 ppm) of ethanolic and aqueous extracts, the J2s were permanently paralyzed; however, at low concentrations, only the ethanolic extract was effective. The ethanolic extract paralyzed J2s at concentrations higher than 62.5 ppm and reduced the egg hatching by up to 76% compared to the control treatment. In general, the efficacy of the aqueous extract was considerably lower than that of the ethanolic extract.

The continuous provision of nitrogen (N) to the crop is critical for optimal cotton production; however, the constant and excessive application of synthetic fertilizers causes adverse impacts on soil, plants, animals, and human health. The current study focused on the short-term effects (one-year study) of adding different rates of clinoptilolite zeolite, as part of an integrated nutrient management plan, and different rates of inorganic N fertilizer to improve soil and crop performance of cotton in three locations (ATH, MES, and KAR) in Greece. Each experiment was set up according to a split-plot design with three replications, three main plots (zeolite application at rates of 0, 5, and 7.5 t ha⁻¹), and four sub-plots (N fertilization regimes at rates of 0, 100, 150, and 200 kg N ha⁻¹). The results of this study indicated that increasing rates of the examined factors increased cotton yields (seed cotton yield, lint yield, and lint percentage), with the greatest lint yield recorded under the highest rates of zeolite (7.5 t ha⁻¹: 1808, 1723, and 1847 kg ha⁻¹ in ATH, MES, and KAR, respectively) and N fertilization (200 kg N ha⁻¹: 1804, 1768, and 1911 kg ha⁻¹ in ATH, MES, and KAR, respectively). From the evaluated parameters, most soil parameters (soil organic matter, soil total nitrogen, and total porosity), root and shoot development (root length density, plant height, leaf area index, and dry weight), fiber maturity traits (micronaire, maturity, fiber strength, and elongation), fiber length traits (upper half mean length, uniformity index, and short fiber index), as well as color (reflectance and spinning consistency index) and trash traits (trash area and trash grade), were positively impacted by the increasing rates of the evaluated factors. In conclusion, the results of the present research suggest that increasing zeolite and N fertilization rates to 7.5 t ha⁻¹ and 200 kg N ha⁻¹, respectively, improved soil properties (except mean weight diameter), stimulated crop development, and enhanced cotton and lint yield, as well as improved the fiber maturity, length, and color parameters of cotton grown in clay-loam soils in the Mediterranean region.