Figure 1.
Effect of different inoculant dosages on the number of leaves of tomato seedlings. Tomato seeds were sown in substrates mixed with seven dosages of Bacillus methylotrophicus (0, 0.25, 0.50, 0.75, 1.00, 1.25, and 1.50 g/strain), which were recorded as CK, T1, T2, T3, T4, T5, and T6, respectively, with three replications for each treatment, that is, one for each cavity tray. Different letters above the bars at the same days are significantly different among treatments at the 0.05 level.
Figure 1.
Effect of different inoculant dosages on the number of leaves of tomato seedlings. Tomato seeds were sown in substrates mixed with seven dosages of Bacillus methylotrophicus (0, 0.25, 0.50, 0.75, 1.00, 1.25, and 1.50 g/strain), which were recorded as CK, T1, T2, T3, T4, T5, and T6, respectively, with three replications for each treatment, that is, one for each cavity tray. Different letters above the bars at the same days are significantly different among treatments at the 0.05 level.
Figure 2.
Effect of different inoculant dosages on the above-ground morphology of tomato seedlings. Tomato seeds were sown in substrates mixed with seven dosages of Bacillus methylotrophicus (0, 0.25, 0.50, 0.75, 1.00, 1.25, and 1.50 g/strain), which were recorded as CK, T1, T2, T3, T4, T5, and T6, respectively, with three replications for each treatment, that is, one for each cavity tray. Different letters above the bars are significantly different among treatments at the 0.05 level.
Figure 2.
Effect of different inoculant dosages on the above-ground morphology of tomato seedlings. Tomato seeds were sown in substrates mixed with seven dosages of Bacillus methylotrophicus (0, 0.25, 0.50, 0.75, 1.00, 1.25, and 1.50 g/strain), which were recorded as CK, T1, T2, T3, T4, T5, and T6, respectively, with three replications for each treatment, that is, one for each cavity tray. Different letters above the bars are significantly different among treatments at the 0.05 level.
Figure 3.
Effect of different inoculant dosages on the chlorophyll content and correlation of tomato seedlings. (a) Leaf dry and fresh weight ratio. (b–d) Chlorophyll a, b, and a + b contents, respectively. (e) Chlorophyll a/b value. (f) Correlation between leaf dry-to-fresh weight ratio and chlorophyll content. Tomato seeds were sown in substrates mixed with seven dosages of Bacillus methylotrophicus (0, 0.25, 0.50, 0.75, 1.00, 1.25, and 1.50 g/strain), which were recorded as CK, T1, T2, T3, T4, T5, and T6, respectively, with three replications for each treatment, that is, one for each cavity tray. The different letters on the graphs are significantly different between treatments at the 0.05 level.
Figure 3.
Effect of different inoculant dosages on the chlorophyll content and correlation of tomato seedlings. (a) Leaf dry and fresh weight ratio. (b–d) Chlorophyll a, b, and a + b contents, respectively. (e) Chlorophyll a/b value. (f) Correlation between leaf dry-to-fresh weight ratio and chlorophyll content. Tomato seeds were sown in substrates mixed with seven dosages of Bacillus methylotrophicus (0, 0.25, 0.50, 0.75, 1.00, 1.25, and 1.50 g/strain), which were recorded as CK, T1, T2, T3, T4, T5, and T6, respectively, with three replications for each treatment, that is, one for each cavity tray. The different letters on the graphs are significantly different between treatments at the 0.05 level.
Figure 4.
Effect of different inoculant dosages on the G value and seedling index of tomato seedlings. Tomato seeds were sown in substrates mixed with seven dosages of Bacillus methylotrophicus (0, 0.25, 0.50, 0.75, 1.00, 1.25, and 1.50 g/strain), which were recorded as CK, T1, T2, T3, T4, T5, and T6, respectively, with three replications for each treatment, that is, one for each cavity tray. Different letters above the bars are significantly different among treatments at the 0.05 level.
Figure 4.
Effect of different inoculant dosages on the G value and seedling index of tomato seedlings. Tomato seeds were sown in substrates mixed with seven dosages of Bacillus methylotrophicus (0, 0.25, 0.50, 0.75, 1.00, 1.25, and 1.50 g/strain), which were recorded as CK, T1, T2, T3, T4, T5, and T6, respectively, with three replications for each treatment, that is, one for each cavity tray. Different letters above the bars are significantly different among treatments at the 0.05 level.
Figure 5.
Effect of different inoculant dosages on the root traits of tomato seedlings. Tomato seeds were sown in substrates mixed with seven dosages of Bacillus methylotrophicus (0, 0.25, 0.50, 0.75, 1.00, 1.25, and 1.50 g/strain), which were recorded as CK, T1, T2, T3, T4, T5, and T6, respectively, with three replications for each treatment, that is, one for each cavity tray. Different letters above the bars are significantly different among treatments at the 0.05 level.
Figure 5.
Effect of different inoculant dosages on the root traits of tomato seedlings. Tomato seeds were sown in substrates mixed with seven dosages of Bacillus methylotrophicus (0, 0.25, 0.50, 0.75, 1.00, 1.25, and 1.50 g/strain), which were recorded as CK, T1, T2, T3, T4, T5, and T6, respectively, with three replications for each treatment, that is, one for each cavity tray. Different letters above the bars are significantly different among treatments at the 0.05 level.
Figure 6.
Effect of different inoculant dosages on root traits with different diameters of tomato seedlings. Tomato seeds were sown in substrates mixed with seven dosages of Bacillus methylotrophicus (0, 0.25, 0.50, 0.75, 1.00, 1.25, and 1.50 g/strain), which were recorded as CK, T1, T2, T3, T4, T5, and T6, respectively, with three replications for each treatment, that is, one for each cavity tray. Different letters above the bars at the same grading are significantly different among treatments at the 0.05 level.
Figure 6.
Effect of different inoculant dosages on root traits with different diameters of tomato seedlings. Tomato seeds were sown in substrates mixed with seven dosages of Bacillus methylotrophicus (0, 0.25, 0.50, 0.75, 1.00, 1.25, and 1.50 g/strain), which were recorded as CK, T1, T2, T3, T4, T5, and T6, respectively, with three replications for each treatment, that is, one for each cavity tray. Different letters above the bars at the same grading are significantly different among treatments at the 0.05 level.
Figure 7.
Hierarchical cluster analysis of root traits of tomato seedlings. The indicators in the box are representative indicators.
Figure 7.
Hierarchical cluster analysis of root traits of tomato seedlings. The indicators in the box are representative indicators.
Figure 8.
Correlation of nutrition and root indicators with tomato seedling morphology and quality. A–D represent four types of root indicators.
Figure 8.
Correlation of nutrition and root indicators with tomato seedling morphology and quality. A–D represent four types of root indicators.
Figure 9.
Effect of physical and chemical properties of substrate on root traits and nutrient uptake in tomato seedlings.
Figure 9.
Effect of physical and chemical properties of substrate on root traits and nutrient uptake in tomato seedlings.
Table 1.
Effect of different inoculant dosages on the fresh weight of tomato seedlings.
Table 1.
Effect of different inoculant dosages on the fresh weight of tomato seedlings.
Treatment | Fresh Weight (g/strain) | Fresh Weight Proportion (%) | Root–Shoot Ratio (Fresh) |
---|
Root | Stem | Leaf | Total | Root | Stem | Leaf |
---|
CK | 0.28 ± 0.01 cd | 0.92 ± 0.25 e | 0.73 ± 0.17 d | 1.93 ± 0.41 e | 15.16 ± 3.74 a | 47.30 ± 3.06 d | 37.54 ± 0.68 b | 0.18 ± 0.05 a |
T1 | 0.29 ± 0.02 cd | 0.81 ± 0.04 e | 1.14 ± 0.09 b | 2.24 ± 0.14 e | 12.95 ± 0.03 a | 36.03 ± 0.67 e | 51.03 ± 0.64 a | 0.15 ± 0.00 ab |
T2 | 0.31 ± 0.05 bcd | 2.10 ± 0.04 ab | 1.22 ± 0.04 ab | 3.62 ± 0.13 ab | 8.41 ± 1.04 b | 57.91 ± 0.95 a | 33.68 ± 0.09 d | 0.09 ± 0.01 c |
T3 | 0.32 ± 0.03 abc | 1.81 ± 0.09 c | 1.10 ± 0.06 bc | 3.23 ± 0.17 c | 9.79 ± 0.72 b | 56.16 ± 0.94 abc | 34.05 ± 0.22 d | 0.11 ± 0.01 c |
T4 | 0.36 ± 0.02 a | 2.24 ± 0.09 a | 1.35 ± 0.03 a | 3.96 ± 0.07 a | 9.04 ± 0.60 b | 56.71 ± 1.57 ab | 34.25 ± 1.04 d | 0.10 ± 0.01 c |
T5 | 0.35 ± 0.02 ab | 1.90 ± 0.14 bc | 1.23 ± 0.06 ab | 3.48 ± 0.08 bc | 10.07 ± 0.65 b | 54.45 ± 3.01 bc | 35.48 ± 2.36 cd | 0.11 ± 0.01 bc |
T6 | 0.26 ± 0.01 d | 1.41 ± 0.11 d | 0.98 ± 0.07 c | 2.65 ± 0.18 d | 9.85 ± 0.45 b | 53.03 ± 0.39 c | 37.12 ± 0.05 bc | 0.11 ± 0.01 c |
Table 2.
Effect of different inoculant dosages on the dry weight of tomato seedlings.
Table 2.
Effect of different inoculant dosages on the dry weight of tomato seedlings.
Treatment | Dry Weight (10−1 g/strain) | Dry Weight Proportion (%) | Root–Shoot Ratio (Dry) |
---|
Root | Stem | Leaf | Total | Root | Stem | Leaf |
---|
CK | 0.17 ± 0.01 cd | 0.44 ± 0.17 c | 0.74 ± 0.17 c | 1.34 ± 0.29 c | 12.94 ± 3.00 a | 31.88 ± 4.60 d | 55.18 ± 1.60 abc | 0.15 ± 0.04 a |
T1 | 0.17 ± 0.01 cd | 0.53 ± 0.02 bc | 0.89 ± 0.02 b | 1.58 ± 0.04 bc | 10.73 ± 0.32 ab | 33.16 ± 0.03 cd | 56.11 ± 0.29 ab | 0.12 ± 0.00 b |
T2 | 0.19 ± 0.02 bc | 0.84 ± 0.00 a | 1.17 ± 0.07 a | 2.20 ± 0.03 a | 8.44 ± 1.15 c | 38.28 ± 0.88 a | 53.28 ± 2.03 c | 0.09 ± 0.01 b |
T3 | 0.21 ± 0.01 ab | 0.79 ± 0.03 a | 1.19 ± 0.05 a | 2.19 ± 0.04 a | 9.48 ± 0.34 bc | 36.01 ± 1.63 abc | 54.50 ± 1.37 bc | 0.10 ± 0.00 b |
T4 | 0.20 ± 0.02 ab | 0.87 ± 0.03 a | 1.29 ± 0.04 a | 2.37 ± 0.04 a | 8.58 ± 0.43 bc | 36.92 ± 1.30 ab | 54.50 ± 1.30 bc | 0.09 ± 0.01 b |
T5 | 0.21 ± 0.02 a | 0.76 ± 0.00 a | 1.25 ± 0.09 a | 2.22 ± 0.09 a | 9.44 ± 0.54 bc | 34.14 ± 1.75 bcd | 56.41 ± 1.28 ab | 0.10 ± 0.01 b |
T6 | 0.16 ± 0.00 d | 0.59 ± 0.05 b | 1.00 ± 0.07 b | 1.75 ± 0.09 b | 9.15 ± 0.59 bc | 33.63 ± 0.49 bcd | 57.22 ± 0.10 a | 0.10 ± 0.01 b |
Table 3.
Ratio of G1–G2 to G5 root indicators of tomato seedlings.
Table 3.
Ratio of G1–G2 to G5 root indicators of tomato seedlings.
Treatment | (G1-G2)/G5 |
---|
Root Length | Root Area | Root Volume |
---|
CK | 373.17 ± 22.23 a | 29.02 ± 1.21 a | 3.27 ± 0.54 a |
T1 | 373.70 ± 4.37 a | 27.36 ± 2.41 a | 2.95 ± 0.41 ab |
T2 | 159.71 ± 2.48 c | 11.31 ± 0.82 c | 1.18 ± 0.07 d |
T3 | 255.63 ± 18.52 b | 19.58 ± 1.35 b | 2.41 ± 0.09 bc |
T4 | 251.43 ± 20.30 b | 16.90 ± 0.70 b | 1.85 ± 0.08 c |
T5 | 236.03 ± 47.10 b | 17.94 ± 0.96 b | 2.01 ± 0.14 c |
T6 | 284.85 ± 31.10 b | 28.17 ± 3.73 a | 3.48 ± 0.48 a |
Table 4.
Mineral nutrient accumulation and distribution ratio in various organs of tomato seedlings under different treatments.
Table 4.
Mineral nutrient accumulation and distribution ratio in various organs of tomato seedlings under different treatments.
Nutrient | Treatment | Accumulation (mg/strain) | Total | Distribution Ratio (%) |
---|
Root | Stem | Leaf | Root | Stem | Leaf |
---|
Total nitrogen | CK | 0.48 ± 0.01 b | 1.00 ± 0.12 c | 3.36 ± 0.46 c | 4.84 ± 0.57 c | 9.98 ± 0.21 a | 20.69 ± 2.45 bc | 69.32 ± 9.40 a |
T1 | 0.40 ± 0.03 c | 0.94 ± 0.02 c | 3.34 ± 0.25 c | 4.68 ± 0.25 c | 8.56 ± 0.73 b | 20.15 ± 0.36 bc | 71.29 ± 5.36 a |
T2 | 0.44 ± 0.04 bc | 1.39 ± 0.13 b | 4.55 ± 0.41 b | 6.38 ± 0.33 b | 6.96 ± 0.65 cde | 21.80 ± 2.07 b | 71.24 ± 6.43 a |
T3 | 0.50 ± 0.02 b | 1.39 ± 0.09 b | 4.49 ± 0.22 b | 6.37 ± 0.27 b | 7.80 ± 0.25 bc | 21.76 ± 1.36 b | 70.44 ± 3.46 a |
T4 | 0.44 ± 0.01 bc | 1.85 ± 0.29 a | 4.49 ± 0.92 b | 6.78 ± 0.67 b | 6.55 ± 0.14 de | 27.26 ± 4.26 a | 66.19 ± 13.55 a |
T5 | 0.59 ± 0.07 a | 1.68 ± 0.09 a | 5.56 ± 0.38 a | 7.83 ± 0.33 a | 7.53 ± 0.93 bcd | 21.43 ± 1.14 b | 71.04 ± 4.84 a |
T6 | 0.39 ± 0.06 c | 1.09 ± 0.16 c | 4.83 ± 0.17 ab | 6.31 ± 0.21 b | 6.22 ± 0.88 e | 17.26 ± 2.53 c | 76.52 ± 2.64 a |
Total phosphorus | CK | 0.23 ± 0.01 a | 0.51 ± 0.03 c | 0.92 ± 0.12 d | 1.66 ± 0.16 c | 13.72 ± 0.40 a | 30.66 ± 2.09 ab | 55.62 ± 7.11 b |
T1 | 0.19 ± 0.02 b | 0.56 ± 0.01 bc | 1.04 ± 0.07 bcd | 1.79 ± 0.07 bc | 10.80 ± 0.89 b | 31.24 ± 0.51 ab | 57.96 ± 4.09 b |
T2 | 0.17 ± 0.02 bc | 0.66 ± 0.05 a | 1.22 ± 0.09 ab | 2.05 ± 0.05 a | 8.23 ± 0.74 cd | 32.32 ± 2.58 a | 59.45 ± 4.36 b |
T3 | 0.18 ± 0.00 b | 0.60 ± 0.04 ab | 1.18 ± 0.05 ab | 1.95 ± 0.07 ab | 9.31 ± 0.23 c | 30.47 ± 1.83 ab | 60.21 ± 2.37 b |
T4 | 0.16 ± 0.00 c | 0.68 ± 0.10 a | 1.12 ± 0.20 abc | 1.96 ± 0.13 a | 8.11 ± 0.12 d | 34.57 ± 4.86 a | 57.32 ± 10.22 b |
T5 | 0.18 ± 0.02 bc | 0.53 ± 0.03 bc | 1.26 ± 0.07 a | 1.97 ± 0.08 a | 9.08 ± 1.01 cd | 27.03 ± 1.40 b | 63.89 ± 3.69 ab |
T6 | 0.09 ± 0.01 d | 0.30 ± 0.04 d | 0.97 ± 0.03 cd | 1.36 ± 0.04 d | 6.71 ± 0.71 e | 21.75 ± 2.63 c | 71.54 ± 2.04 a |
Total potassium | CK | 0.71 ± 0.03 b | 3.02 ± 0.36 c | 2.87 ± 0.35 d | 6.60 ± 0.16 d | 10.71 ± 0.39 a | 45.75 ± 5.41 ab | 43.54 ± 5.27 bc |
T1 | 0.68 ± 0.04 b | 3.60 ± 0.06 c | 3.56 ± 0.21 c | 7.84 ± 0.23 c | 8.65 ± 0.55 b | 45.92 ± 0.78 ab | 45.43 ± 2.62 bc |
T2 | 0.70 ± 0.05 b | 5.33 ± 0.42 ab | 4.96 ± 0.41 a | 10.99 ± 0.83 ab | 6.36 ± 0.49 d | 48.54 ± 3.78 a | 45.11 ± 3.76 bc |
T3 | 0.78 ± 0.03 a | 5.13 ± 0.29 b | 4.94 ± 0.25 a | 10.85 ± 0.43 ab | 7.19 ± 0.24 c | 47.30 ± 2.70 a | 45.51 ± 2.32 bc |
T4 | 0.66 ± 0.00 b | 6.14 ± 0.97 a | 4.61 ± 0.72 ab | 11.41 ± 0.43 a | 5.81 ± 0.00 d | 53.77 ± 8.46 a | 40.41 ± 6.27 c |
T5 | 0.69 ± 0.05 b | 4.88 ± 0.32 b | 4.97 ± 0.24 a | 10.54 ± 0.14 b | 6.56 ± 0.47 cd | 46.28 ± 3.06 ab | 47.16 ± 2.26 b |
T6 | 0.50 ± 0.05 c | 3.04 ± 0.35 c | 4.25 ± 0.16 b | 7.79 ± 0.24 c | 6.45 ± 0.63 cd | 39.04 ± 4.50 b | 54.52 ± 1.99 a |
Table 5.
Effect of different inoculant dosages on physical and chemical properties of the substrate.
Table 5.
Effect of different inoculant dosages on physical and chemical properties of the substrate.
Treatment | EC (10−1 mS/m) | pH | Substrate Carbon Content (%) |
---|
Total Carbon | Inorganic Carbon | Total Organic Carbon | Inorganic Carbon/Total Organic Carbon |
---|
Original substrate | 150.00 ± 3.00 f | 6.21 ± 0.03 d | 29.65 ± 1.13 b | 0.00 ± 0.00 d | 29.65 ± 1.13 b | 0.00 ± 0.00 e |
CK | 449.33 ± 6.11 d | 5.18 ± 0.03 e | 28.33 ± 0.95 bc | 0.00 ± 0.00 d | 28.33 ± 0.95 bc | 0.00 ± 0.00 e |
T1 | 346.00 ± 3.61 e | 6.24 ± 0.15 d | 26.37 ± 0.22 e | 0.00 ± 0.00 d | 26.37 ± 0.22 de | 0.00 ± 0.00 e |
T2 | 440.67 ± 6.11 d | 7.44 ± 0.03 ab | 31.50 ± 0.79 a | 0.00 ± 0.00 d | 31.50 ± 0.79 a | 0.00 ± 0.00 e |
T3 | 476.33 ± 13.05 c | 7.13 ± 0.08 c | 29.31 ± 0.56 b | 0.05 ± 0.01 d | 29.28 ± 0.53 b | 0.15 ± 0.02 d |
T4 | 490.33 ± 12.74 c | 7.53 ± 0.06 a | 27.83 ± 0.29 cd | 0.14 ± 0.01 c | 27.74 ± 0.22 cd | 0.49 ± 0.02 c |
T5 | 553.00 ± 16.09 b | 7.54 ± 0.04 a | 26.84 ± 0.42 de | 0.57 ± 0.05 b | 26.28 ± 0.37 e | 2.15 ± 0.17 b |
T6 | 868.00 ± 17.09 a | 7.39 ± 0.03 b | 23.77 ± 1.27 f | 0.93 ± 0.07 a | 23.14 ± 1.35 f | 4.10 ± 0.01 a |
Table 6.
Effect of different inoculant dosages on the enzyme activity of the substrate.
Table 6.
Effect of different inoculant dosages on the enzyme activity of the substrate.
Treatment | URE (mg/g/d) | SUC (mg/g/d) | CAT (mg/g/d) | ALP (mg/g/d) |
---|
Original substrate | - | - | - | - |
CK | 0.18 ± 0.03 d | 13.34 ± 1.53 b | 7.84 ± 0.77 d | 0.78 ± 0.03 a |
T1 | 0.64 ± 0.06 c | 11.78 ± 1.67 b | 8.28 ± 0.33 cd | 0.71 ± 0.02 a |
T2 | 0.73 ± 0.06 bc | 54.89 ± 2.41 a | 9.00 ± 0.12 ab | 0.73 ± 0.05 a |
T3 | 0.72 ± 0.05 bc | 47.29 ± 5.73 a | 9.48 ± 0.29 a | 0.75 ± 0.01 a |
T4 | 0.73 ± 0.02 bc | 51.74 ± 5.73 a | 9.06 ± 0.19 ab | 0.69 ± 0.09 a |
T5 | 0.83 ± 0.04 b | 56.07 ± 8.44 a | 9.15 ± 0.37 ab | 0.69 ± 0.06 a |
T6 | 1.18 ± 0.13 a | 52.06 ± 7.47 a | 8.54 ± 0.19 bc | 0.71 ± 0.11 a |
Table 7.
Explanation and significance tests for substrate properties in RDA.
Table 7.
Explanation and significance tests for substrate properties in RDA.
Substrate Properties | Simple Effects | Conditional Effects |
---|
Explanation % | Pseudo-F | p | Explanation % | Pseudo-F | p |
---|
SUC | 43.50 | 14.60 | 0.002 | 43.50 | 14.60 | 0.002 |
pH | 41.00 | 13.20 | 0.002 | 2.00 | 1.40 | 0.162 |
CAT | 30.20 | 8.20 | 0.002 | 1.20 | 0.90 | 0.502 |
URE | 24.90 | 6.30 | 0.002 | 4.80 | 3.00 | 0.014 |
EC | 23.80 | 5.90 | 0.002 | 24.50 | 13.80 | 0.002 |
IC/TOC | 23.90 | 6.00 | 0.004 | 1.40 | 1.00 | 0.344 |
IC | 24.20 | 6.10 | 0.002 | 1.00 | 0.70 | 0.644 |
TOC | 17.50 | 4.00 | 0.014 | 3.80 | 2.60 | 0.022 |
TC | 17.40 | 4.00 | 0.022 | 0.60 | 0.40 | 0.886 |
ALP | 5.00 | 1.00 | 0.41 | 1.80 | 1.30 | 0.248 |