## 3 Results
### Biochars as Amendment for Greenhouse Media for Seeding Production
#### 3.2.2 Basil Seedling Growth  
The total fresh weight (TFW), total dry weight (TDW) and GI of seedlings in SBB-amended mixes had positive linear correlations with the biochar incorporation rate, while seedlings in HB-amended mixes showed quadratic correlations (Figure 5a-c). All TFWs (except 30% and 50% HB), TDWs and GIs (except 50% HB) in biochar-amended mixes were significantly lower than the control. Basil seedlings grown in all biochar-amended mixes had similar or higher SPAD than the control (except 100% SBB, Figure 5d). \begin{table}
\begin{tabular}{l c c c c} \hline
**Mixes \({}^{\mathbf{z}}\)** & **Root Length (cm)** & **Root Surface Area** & **Average Diameter** & **Number of Tips** \\  & & **(cm\({}^{\mathbf{2}}\))** & **(mm)** & \\ \hline SBB:PM:P(10:60:30) & 125 \(\pm\) 10**\({}^{\mathbf{\ast}}\) & 27 \(\pm\) 3**\({}^{\mathbf{\ast}\mathbf{\ast}}\) & 0.69 \(\pm\) 0.05**\({}^{\mathbf{\ast}\mathbf{\ast}}\) & 410 \(\pm\) 45**\({}^{\mathbf{\ast}\mathbf{\ast}}\) \\ SBB:PM:P(30:40:30) & 209 \(\pm\) 8**\({}^{\mathbf{\ast\ast}}\) & 37 \(\pm\) 1**\({}^{\mathbf{\ast\ast}}\) & 0.57 \(\pm\) 0.01 & 625 \(\pm\) 60**\({}^{\mathbf{\ast\ast}}\) \\ SBB:PM:P(50:20:30) & 277 \(\pm\) 27**\({}^{\mathbf{\ast\ast}}\) & 55 \(\pm\) 4 & 0.64 \(\pm\) 0.03* & 789 \(\pm\) 120* \\ SBB:PM:P(70:00:30) & 259 \(\pm\) 26**\({}^{\mathbf{\ast\ast}}\) & 49 \(\pm\) 4* & 0.60 \(\pm\) 0.02 & 657 \(\pm\) 26**\({}^{\mathbf{\ast\ast}}\) \\ SBB:PM:P(100:0:0) & 281 \(\pm\) 50* & 52 \(\pm\) 7* & 0.60 \(\pm\) 0.03 & 718 \(\pm\) 91* \\ HB:PM(10:90) & 243 \(\pm\) 36**\({}^{\mathbf{\ast\ast}}\) & 46 \(\pm\) 5**\({}^{\mathbf{\ast\ast}}\) & 0.62 \(\pm\) 0.04 & 648 \(\pm\) 30* \\ HB:PM(30:70) & 350 \(\pm\) 26 & 64 \(\pm\) 4 & 0.58 \(\pm\) 0.04 & 817 \(\pm\) 64 \\ HB:PM(50:50) & 278 \(\pm\) 31**\({}^{\mathbf{\ast\ast}}\) & 56 \(\pm\) 3 & 0.66 \(\pm\) 0.05* & 1055 \(\pm\) 148 \\ HB:PM(70:30) & 271 \(\pm\) 21**\({}^{\mathbf{\ast\ast}}\) & 50 \(\pm\) 2* & 0.60 \(\pm\) 0.02 & 746 \(\pm\) 47* \\ Control & 432 \(\pm\) 35 & 68 \(\pm\) 4 & 0.50 \(\pm\) 0.01 & 1147 \(\pm\) 141 \\ \hline \end{tabular}  
* \({}^{\mathbf{\ast}}\) SBB = sugarcane bagasse biochar; HB = mixed hardwood biochar; P = perlite; PM = peat moss; Control = commercial propagation substrate. Numbers in parentheses indicate the ratio of different components, by vol.  
\end{table} 
Table 2: Root growth of tomato seedlings grown in different mixes (*, ** indicate a significant difference from the control using Dunnett’s test at \(p\leq\) 0.05 and \(p\leq\) 0.01, respectively). Figure 4: The correlations between total fresh weight (TFW, **a**), total dry weight (TDW, **b**), growth index (GI, **c**) and biochar incorporation rate and the soil-Plant Analyses development (SPAD) **(d)** of tomato seedlings grown in biochar-amended mixes. SBB = sugarcane bagasse biochar; HB = mixed hardwood biochar; CS = commercial propagation substrate. SBB (10%, 30%, 50%, 70% and 100%; by vol.) incorporated with 30% perlite with the rest being peat moss; HB (10%, 30%, 50% and 70%; by vol.) incorporated with peat moss. (*, ** indicated significant difference from the control using [PERSON]’s test at \(p\leq\) 0.05 and \(p\leq\) 0.01, respectively). All basil seedlings grown in biochar-amended mixes had significantly shorter root lengths, smaller root surface areas and fewer root tips than the control (Table 3); however, they all had similar root diameters.