Mycelium characteristics of the T. versicolor mushroom
The effect of growth media on mycelium growth, density of hyphae, and full colonization of the Petri dish was significantly different (p<0.05; Fig. 1B, C, and Fig. 3). The pigmentation and colonies of the T. versicolor mushroom were white, showing smooth texture, abundant aerial hyphae, and high density in both growth media (Fig. 1). Therefore, MEA and PDA media were ideal growth media for the enhanced mycelium development of T. versicolor mushrooms. On the other hand, mycelium growth and the growth performance of the strain were slightly higher on MEA than on PDA, as shown in (Fig. 3). In both growth media, the mushroom exhibited luxurious growth and completed colonization of the Petri dish in 8 days on MEA and 10 days, respectively (Fig. 3). Hence, the growth performance of the strain on MEA and PDA showed statistically significant differences (p<0.05) at days 2, 4, 6, and 8 (Fig. 3). Particularly, after 8 days of incubation, MEA and PDA revealed the highest growth diameter (mm/day) with 89.33 and 78, respectively. However, 89.33 mm/day of mycelial growth diameter of the strain was recorded when grown on PDA after 10 days (Fig. 3). Weak mycelium growth was observed on the PDA medium, and the strain grew more favorably on the MEA medium, with decreased colonization of the medium within 8 days at 25 oC. Hence, MEA medium was an efficient and suitable growth medium for the fast mycelial extension of T. versicolor mushrooms
Biochemical composition of the substrates
Substrates differed significantly in terms of their C, N, and C: N, cellulose, hemicellulose, and lignin contents (p < 0.05, Table 2). Hence, S8 had the highest C content, followed by S7 and S2, whereas S4 and S5 had the lowest C content (Table 2). Substrates S7 (100% sugarcane bagasse) and S9 had significantly lower N content (0.53% and 0.89) than the other substrates (p < 0.05). Accordingly, the N content of S1 (2.04) was significantly higher than that of the other substrates (p < 0.05; Table 2). The C:N ratio of the different substrates ranged from 19.69 (S1) to 86.96 (S7) (Table 2). The results of this study revealed that the N content increased gradually with the addition of potential animal manures to the designed substrate formulas (Table 1).
In addition, significant (p < 0.05) differences were found between different substrates in terms of their cellulose, hemicellulose, and lignin contents (Table 2). S9 had the highest cellulose content (41.55%), but S6 had the lowest content (25.56%) (Table 2). Similarly, S2 had the highest hemicellulose content (26.59%), but S5 had the lowest hemicellulose content. On the other hand, S4 had the highest lignin content (22.96%), followed by S1 and S7 (Table 2).
Substrate Mineral Content
Mineral elements are significantly varied among substrates (Table 3; p < 0.05). Na and Mg contents were significantly higher (p < 0.05) in S3 than in the other substrates, whereas Zn and Fe contents were significantly higher in S4 and S6, respectively. Ca and K values were significantly higher in S5 and S9 (p < 0.05; Table 3). The contents of Zn, Mg, K, and Ca were significantly lower in S7 than in the other substrates (p < 0.05; Table 3).
Mycelial growth rate and Spawn run time
The combinations of different ingredients with sugarcane bagasse had significant differences (p < 0.05; Table 4) in the mycelial growth rate, surface mycelial density, and spawn run time. The mycelial growth rate (mm/day) of T. versicolor mushroom was significantly faster on the S5 (18.90 mm/day; Table 4) than that grown on the S7 (12.76 mm/day), which is the control substrate among other substrates. Moreover, the mycelial growth rate ranged from 12.76 to 18.90 mm/day, including 100% sugarcane bagasse. Treatments S7, S8, and S9 showed poor mycelial density, while S1 to S6 showed excellent mycelial growth throughout the whole bags with a uniform and thick white mycelial appearance (Fig. 4a). Spawn run time ranged from 15.67 (S5) to 23.33 days (S7; Table 4). Hence, S5 had the shortest spawn run time (15.67 days) to fully colonize the substrate bags.
Pinhead Formation, Fructification and First harvest time
The shortest pinhead formation was obtained from S5 (5.35 days), while the longest one was obtained from S7 (13.33 days), followed by S8, S9, and S6 (Table 4). However, the number of days required for pinhead formation on substrates S1, S2, S4, and S10 did not vary significantly (p> 0.05; Table 4). In addition to pinhead formation, uniform distributions and localization of pinheads on the growth substrate were observed (Fig. 4B). This study verifies that optimum yield and quality of fruiting bodies could be obtained when mushrooms grew on a substrate containing sugarcane bagasse with chicken manure, cow dung, and horse manure. The fruiting bodies of T. versicolor were produced on all ten (10) substrates formulated (Table 1). Fructification differed significantly between substrates (p< 0.05; Table 4). Early fructification was observed on S3 (6.67 days), while the longest time was on S7 (12 days). However, the days to fructification on S3 did not differ significantly from those on S2 and S5 (p > 0.05; Table 4). On the other hand, S7 and S8 recorded the longest fructification days compared to the other substrates (Table 4). The number of days to first harvest differed significantly among the substrates (p< 0.05; Table 4). The shortest first harvesting time occurred after 19 days on S5, while the longest time was obtained from S7 (34.33 days) and S4 (24 days), respectively (Table 4).
Cap Diameter of T.versicolor mushroom
The type of artificial substrate used significantly affected T. versicolor mushroom cap diameter (p < 0.05; Table 4). The cap diameters of mushrooms developed on substrates S7 (5.76 cm), S2 (5.71 cm), and S1 (5 cm). However, the cap diameters of mushrooms that developed on substrates S4, S5, S6, and S10 were smaller than those that grew on other substrates.
Total Yield and Biological Efficiency
T. versicolor mushroom yield and biological efficiency were significantly affected by substrate type and formulations (p < 0.05; Table 5). The highest yield (158.33 g/500 g of substrate) and biological efficiency (31.66%) were obtained from S5, but significantly lower yield (57.67 g/500 g) and biological efficiency (11.73%) were obtained from S7 compared to other substrates (p < 0.05).
Nutritional composition of T. versicular mushroom
The crude protein content of T. versicolor mushrooms from different substrates varied significantly (p < 0.05; Table 6). Significantly higher crude protein content (14.65%) was obtained from S5, followed by S1 (14.27%) (p < 0.05), but significantly lower content (7.46%) was recorded from S7 compared to other substrates (p< 0.05; Table 6). The crude fiber analysis revealed that there were significant (p<0.05; Table 6) differences among substrates. High (18.38%) and low (12.89%) crude fiber contents were recorded from the mushrooms grown on S5 and S2, respectively. The crude fat contents of the study ranged from 0.42 to 0.52% and significantly varied (p < 0.05; Table 6) in different substrates. The carbohydrate content of T. versicolor mushrooms significantly differed in terms of substrates used for growth (p < 0.05; Table 6). Accordingly, S8 had the highest carbohydrate content (66.75%), followed by S7, S9, and S6. Nevertheless, significantly lower (48.38%) carbohydrate content was obtained from S5 and other substrates (p < 0.05; Table 6)