## 3 Results and Discussion
[55] carried out a laboratory experiment which showed a positive association between biochar, obtained from various biological feedstocks, and increased germination rates in wheat seeds. Generally, the beneficial effects were produced by five types of biochar applied in doses \(<\)50 t h\({}^{-1}\). Conversely, higher doses failed to stimulate the germination process, or even inhibited it. [PERSON] et al., [56] assessed the effects of biochars on seed germination, early growth of _Oryza sativa_ L. In this study, the germination percentage of paddy increased in case of two of three biochar was above the control level but the difference was not significant. The third type of biochar shows decrease in germination percentage than control. Other reports on the related study found that there is no negative impact of biochar on the germination of paddy seeds [57]. The study based on forest seeds found that biochar application increases germination of seeds [58]. [PERSON] et al. [19] showed that by supplementing soil with the most effective dose of biochar defined for that species, it is possible to achieve a 20% increase in the germination rate of Virginia mallow seeds. It was also observed that biochar from plant biomass, introduced to the soil, led to a significant increase in the mass obtained by plants in the early stages of their development [19]. Figure 2 presents the total mass of the seedlings harvested after 14 days of the experiment, relative to the sample type. The total mass of the plants collected from the control sample was 0.275 g. The mass of the plants collected from seeds subjected to conditioning with biochar was significantly greater than the mass of the seedlings from seeds subjected to hydroconditioning alone, or those from the control sample. The total mass of the seedlings increased by 73.1% compared to the control sample, and by 25.6% compared to the hydroconditioned sample. Figure 2: The total masses of Virginia mallow seedlings in the experimental variants. According to [PERSON]’s test, means marked with the same letter are not significantly different at \(\alpha\leq 0.05\). The literature on this topic suggests that biochar beneficially affects crop yields, for instance [PERSON] et al. [58] planted lodgepole pine (_Pinus contorta_ var. _latifolia_) or sitka alder (_Almus viridis_ ssp. _sinuata_) seeds in pots containing field-collected forest soils amended with 0.5, or 10% (dry mass basis) biochar with and without urea fertilizer (150 mg N kg\({}^{-1}\)). Pine had greater biomass in biochar fertilizer treatments compared to control and fertilizer-only treatments. Alder seedlings had greater shoot biomass when grown in biochar-amended soils compared with unamended control. According to [PERSON] et al. [59] biochar amendments used in fields at a rate below 30 t h\({}^{-1}\) resulted in increased productivity of these specific crops: legumes by 30%, vegetables--29%, grasses--13%, wheat--11%, maize--8%, rice--7% [59]. [PERSON] et al. [60] demonstrated the positive effects of biochar made from wheat straw in the productivity of rapeseed and sweet potato. A biochar amendment applied at a rate of 40 t ha\({}^{-1}\) resulted in a yield increase of 36.02% and 53.77%, respectively [60]. [PERSON] et al. [61] used wastewater sludge biochar as a fertiliser. With the amendment used at a rate of 10 t h\({}^{-1}\) the yield of cherry tomato increased by 64% compared to control conditions. [PERSON] et al. [62] reported the positive effects of poultry litter biochar, applied at a rate of 10 t h\({}^{-1}\), in the increased mass of radish. [PERSON] et al. [63] investigated the impact of cow manure biochar on maize yield. Biochar amendment applied at rates of 15 t and 20 t h\({}^{-1}\) increased maize grain yield by 150% and 98%, respectively, compared to the control. The findings of the study suggested that cow manure biochar contained important nutrients which significantly contributed to increased maize productivity.