**4. Observations and results**

#### **4.1 Composition of spent mushroom substrate (SMS)**

The empirical data depicted in **Tables 1** and **2** show the composition of Spent Mushroom Substrate (SMS) of *Pleurotus* spp., compared with the substrate, paddy straw. The cellulose and hemicellulose content of paddy straw substrate were 30.25% and 23.18% and dry weight respectively. Cultivation of *Pleurotus eous* on the substrate had lowered the cellulose content by 24.89%. The hemicellulose


#### **Table 1.**

*Biochemical properties of fresh SMS.*


#### **Table 2.**

*Physico chemical properties of fresh SMS.*

utilization was less comparatively, showing a degradation rate of 3.35% from the initial content. The physico-chemical properties of SMS of Fresh SMS had an acidic pH 6.1 and its conductivity was 1.75 mmho.cm−1. It had 72% moisture content. The fresh SMS had 0.87% nitrogen, 0.26% phosphorus, 0.19% potassium and 15% organic carbon. The C/N ratio of fresh SMS was 17.24:1.

### **4.2 Growth studies**

#### *4.2.1 Green gram*

The effect of different concentrations of SMS extract on seedling fresh weight and dry weight of green gram revealed that it is also concentration dependent, as in case of seed germination. Green gram seedlings grown in 60% w/v aqueous SMS extract showed the highest shoot weight (2.112 g). The lowest fresh weight of shoot was observed in 100% of SMS extract (0.621 g). The highest root fresh weight (0.498 g) was found in the green gram seedlings treated with 60% of SMS extract and the lowest root fresh weight (0.157 g) in 100% SMS extract treatment. In case of whole plant, fresh weight of the whole plant was also the highest in 60% of SMS treated seedlings and the lowest in 100% concentration of SMS extract. Control seedlings had 2.074 g as whole plant fresh weight.

The observations regarding the dry weight of shoot, root and whole plant of green gram showed the same response shown for fresh weight. i.e. the seedlings treated with 60% SMS extract produced the highest dry weight values of 0.234 g, 0.056 g and 0.291 g for shoot, root and whole plant respectively. The lowest values of 0.069 g, 0.019 g and 0.069 g for shoot, root and whole plant respectively, were observed on 100% SMS extract treated seedlings. The control seedlings showed 0.187 g dry weight for shoot, 0.043 g for root and 0.230 g for whole plant (**Table 3**).

**253**

**Aqueous SMS conc. (%) (w/v)**

20 40 60 80 100 Control

**Table 3.**

*Effect of SMS on seedling growth of green gram.*

**Shoot** 1.693 ± 0.028 1.620 ± 0.173 2.112 ± 0.053 1.891 ± 0.067 0.621 ± 0.081 1.683 ± 0.020

**Fresh weight (g)**

**Root** 0.430 ± 0.014 0.445 ± 0.012 0.498 ± 0.012 0.453 ± 0.013 0.157 ± 0.033 0.390 ± 0.007

**Whole plant** 2.124 ± 0.038 2.066 ± 0.168 2.610 ± 0.058 2.344 ± 0.079 0.778 ± 0.114 2.074 ± 0.016

**Shoot** 0.188 ± 0.043 0.180 ± 0.019 0.234 ± 0.005 0.210 ± 0.017 0.069 ± 0.009 0.187 ± 0.002

**Dry weight (g)**

**Root** 0.046 ± 0.003 0.049 ± 0.001 0.056 ± 0.003 0.049 ± 0.002 0.019 ± 0.003 0.043 ± 0.002

**Whole plant** 0.234 ± 0.005 0.229 ± 0.019 0.291 ± 0.008

0.259 ± 0.010

0.069 ± 0.009

0.230 ± 0.001

*Screening and Potential Uses of Contaminated Spent Mushroom (*Pleurotus *spp.)*

*DOI: http://dx.doi.org/10.5772/intechopen.93863*

*Screening and Potential Uses of Contaminated Spent Mushroom (*Pleurotus *spp.) DOI: http://dx.doi.org/10.5772/intechopen.93863*


**Table 3.**

*Effect of SMS on seedling growth of green gram.*

*Emerging Contaminants*

Cellulose (% dry wt.)

**Table 1.**

Hemicellulose (% dry wt.)

*Biochemical properties of fresh SMS.*

**Component Untreated substrate** 

utilization was less comparatively, showing a degradation rate of 3.35% from the initial content. The physico-chemical properties of SMS of Fresh SMS had an acidic pH 6.1 and its conductivity was 1.75 mmho.cm−1. It had 72% moisture content. The fresh SMS had 0.87% nitrogen, 0.26% phosphorus, 0.19% potassium and 15%

pH 6.1 EC 1.75 mmho.cm−1 Moisture content 72% N 0.87% P 0.26% K 0.19% Organic carbon 15% C:N 17.24:1

**(paddy straw)**

**Spent mushroom substrate (paddy straw)**

30.25 ± 0.73 23.97 ±0.65 24.89

23.18 ±0.43 22.23 ±0.64 3.35

**Degradation %**

The effect of different concentrations of SMS extract on seedling fresh weight and dry weight of green gram revealed that it is also concentration dependent, as in case of seed germination. Green gram seedlings grown in 60% w/v aqueous SMS extract showed the highest shoot weight (2.112 g). The lowest fresh weight of shoot was observed in 100% of SMS extract (0.621 g). The highest root fresh weight (0.498 g) was found in the green gram seedlings treated with 60% of SMS extract and the lowest root fresh weight (0.157 g) in 100% SMS extract treatment. In case of whole plant, fresh weight of the whole plant was also the highest in 60% of SMS treated seedlings and the lowest in 100% concentration of SMS extract. Control

The observations regarding the dry weight of shoot, root and whole plant of green gram showed the same response shown for fresh weight. i.e. the seedlings treated with 60% SMS extract produced the highest dry weight values of 0.234 g, 0.056 g and 0.291 g for shoot, root and whole plant respectively. The lowest values of 0.069 g, 0.019 g and 0.069 g for shoot, root and whole plant respectively, were observed on 100% SMS extract treated seedlings. The control seedlings showed 0.187 g dry weight for shoot, 0.043 g for root and 0.230 g for whole plant

organic carbon. The C/N ratio of fresh SMS was 17.24:1.

seedlings had 2.074 g as whole plant fresh weight.

**4.2 Growth studies**

*Physico chemical properties of fresh SMS.*

*4.2.1 Green gram*

**Table 2.**

**252**

(**Table 3**).

#### *4.2.2 Black gram*

The results on the effect of SMS extracts on biomass of black gram are given and shown in **Table 4**. In shoot, the fresh weight, 1.824 g was the highest in 60% of SMS treated seedlings and the lowest fresh weight, 1.4 g was observed in 100% concentration of SMS extract. Similarly 60% SMS extract treated seedlings produced the highest fresh root weight value (0.536 g) and 100% of SMS extract treatment showed the least value (0.353 g). The highest whole plant fresh weight value (2.361 g) was found in the seedlings treated with 60% of SMS extract and the lowest value of whole plant fresh weight (1.753 g) was observed in 100% SMS extract treatment compared with the untreated control experiments (1.917 g).

In case of the dry weight of black gram seedlings, the seedlings treated with 40% SMS extract produced the highest dry weight values of 0.212 g and 0.265 g for shoot and whole plant respectively. In root, 0.059 g was found as the highest dry weight in seedlings treated with 60% of SMS extract, followed by 0.053 g in 40% SMS extract treatment. The lowest values of 0.155 g, 0.039 g and 0.194 g for shoot, root and whole plant respectively, were observed on 100% SMS extract treated seedlings. The control seedlings showed 0.171 g dry weight value for shoot, 0.041 g value for root and 0.213 g for whole plant (**Table 4**).

#### *4.2.3 Tomato*

**Table 5** presents the results of the effect of aqueous extract of SMS in different concentrations on biomass of tomato. The highest shoot fresh weight value (4.446 g) was found in the seedlings treated with 60% of SMS extract, followed by 4.048 g in 80% SMS extract treated seedlings. Control seedlings had the lowest value of fresh weight (1.259 g). 1.108 g of root fresh weight was found as the highest in 60% of SMS treated seedlings and 0.301 g as the lowest root fresh weight in control. The 60% SMS treated seedlings produced the highest whole plant fresh weight value (5.554 g) followed by 80% treated seedlings (5.061 g) compared to the control seedlings (1.560 g).

Tomato seedlings, the seedlings treated with 60% of SMS extract produced the highest dry weight values of 0.264 g, 0.065 g and 0.330 g for shoot, root and whole plant respectively. The lowest dry weight values of 0.129 g in shoot of 100% SMS extract treated seedling, 0.039 g and 0.173 g for root and whole plant seedlings respectively, were observed in the seedlings treated as control. (**Table 5**).

#### *4.2.4 Chili*

**Table 6** show the results on the effect of aqueous extract of SMS in different concentrations on biomass of chili. The highest shoot fresh weight value (8.887 g) was found in the seedlings treated with 60% of SMS extract, followed by 5.560 g in 40% treated seedlings and the lowest value of shoot fresh weight (0.779 g) in control. 1.488 g of root fresh weight was found as the highest in 60% of SMS treated seedlings and 0.253 g as the lowest fresh weight of root in control. The 60% SMS extract treated seedlings produced the highest whole plant fresh weight value (10.375 g) followed by 40% treated seedlings (6.848 g). The lowest fresh weight of shoot was observed in control seedlings (1.033 g).

The seedlings treated with 60% SMS extract produced the highest dry weight values of 1.903 g, 0.297 g and 2.200 g for shoot, root and whole plant respectively. The lowest values of 0.086 g, 0.028 g and 0.114 g for shoot, root and whole plant respectively, were observed for the seedlings treated as control (**Table 6**).

**255**

**Aqueous SMS conc. (%) (w/v)**

20 40 60 80 100 Control

**Table 4.**

*Effect of SMS on seedling growth of black gram.*

**Shoot** 1.513 ± 0.063 1.612 ± 0.066 1.824 ± 0.072 1.691 ± 0.066 1.400 ± 0.042 1.544 ± 0.042

**Fresh weight (g)**

**Root** 0.388 ± 0.015 0.482 ± 0.007 0.536 ± 0.008 0.458 ± 0.013 0.353 ± 0.008 0.373 ± 0.009

**Whole plant** 1.902 ± 0.078 2.094 ± 0.066

2.361 ± 0.070 2.149 ± 0.070 1.753 ± 0.050 1.917 ± 0.048

**Shoot** 0.185 ± 0.004 0.212 ± 0.002 0.202 ± 0.008 0.187 ± 0.007 0.155 ± 0.004 0.171 ± 0.004

**Dry weight (g)**

**Root** 0.048 ± 0.007 0.053 ± 0.008 0.059 ± 0.009 0.050 ± 0.001 0.039 ± 0.009 0.041 ± 0.001

**Whole plant** 0.233 ± 0.004 0.265 ± 0.003 0.262 ± 0.007

0.238 ± 0.007

0.194 ± 0.005

0.213 ± 0.005

*Screening and Potential Uses of Contaminated Spent Mushroom (*Pleurotus *spp.)*

*DOI: http://dx.doi.org/10.5772/intechopen.93863*

*Screening and Potential Uses of Contaminated Spent Mushroom (*Pleurotus *spp.) DOI: http://dx.doi.org/10.5772/intechopen.93863*


**Table 4.**

*Effect of SMS on seedling growth of black gram.*

*Emerging Contaminants*

experiments (1.917 g).

*4.2.3 Tomato*

seedlings (1.560 g).

*4.2.4 Chili*

root and 0.213 g for whole plant (**Table 4**).

shoot was observed in control seedlings (1.033 g).

The results on the effect of SMS extracts on biomass of black gram are given

In case of the dry weight of black gram seedlings, the seedlings treated with 40% SMS extract produced the highest dry weight values of 0.212 g and 0.265 g for shoot and whole plant respectively. In root, 0.059 g was found as the highest dry weight in seedlings treated with 60% of SMS extract, followed by 0.053 g in 40% SMS extract treatment. The lowest values of 0.155 g, 0.039 g and 0.194 g for shoot, root and whole plant respectively, were observed on 100% SMS extract treated seedlings. The control seedlings showed 0.171 g dry weight value for shoot, 0.041 g value for

**Table 5** presents the results of the effect of aqueous extract of SMS in different concentrations on biomass of tomato. The highest shoot fresh weight value (4.446 g) was found in the seedlings treated with 60% of SMS extract, followed by 4.048 g in 80% SMS extract treated seedlings. Control seedlings had the lowest value of fresh weight (1.259 g). 1.108 g of root fresh weight was found as the highest in 60% of SMS treated seedlings and 0.301 g as the lowest root fresh weight in control. The 60% SMS treated seedlings produced the highest whole plant fresh weight value (5.554 g) followed by 80% treated seedlings (5.061 g) compared to the control

Tomato seedlings, the seedlings treated with 60% of SMS extract produced the highest dry weight values of 0.264 g, 0.065 g and 0.330 g for shoot, root and whole plant respectively. The lowest dry weight values of 0.129 g in shoot of 100% SMS extract treated seedling, 0.039 g and 0.173 g for root and whole plant seedlings respectively, were observed in the seedlings treated as control. (**Table 5**).

**Table 6** show the results on the effect of aqueous extract of SMS in different concentrations on biomass of chili. The highest shoot fresh weight value (8.887 g) was found in the seedlings treated with 60% of SMS extract, followed by 5.560 g in 40% treated seedlings and the lowest value of shoot fresh weight (0.779 g) in control. 1.488 g of root fresh weight was found as the highest in 60% of SMS treated seedlings and 0.253 g as the lowest fresh weight of root in control. The 60% SMS extract treated seedlings produced the highest whole plant fresh weight value (10.375 g) followed by 40% treated seedlings (6.848 g). The lowest fresh weight of

The seedlings treated with 60% SMS extract produced the highest dry weight values of 1.903 g, 0.297 g and 2.200 g for shoot, root and whole plant respectively. The lowest values of 0.086 g, 0.028 g and 0.114 g for shoot, root and whole plant

respectively, were observed for the seedlings treated as control (**Table 6**).

and shown in **Table 4**. In shoot, the fresh weight, 1.824 g was the highest in 60% of SMS treated seedlings and the lowest fresh weight, 1.4 g was observed in 100% concentration of SMS extract. Similarly 60% SMS extract treated seedlings produced the highest fresh root weight value (0.536 g) and 100% of SMS extract treatment showed the least value (0.353 g). The highest whole plant fresh weight value (2.361 g) was found in the seedlings treated with 60% of SMS extract and the lowest value of whole plant fresh weight (1.753 g) was observed

in 100% SMS extract treatment compared with the untreated control

*4.2.2 Black gram*

**254**


**257**

**Aqueous SMS conc. (%) (w/v)**

20 40 60 80 100 Control

**Table 6.**

*Effect of SMS on seedling growth of chili.*

**Shoot** 5.178 ± 0.201 5.560 ± 0.284 8.887 ± 0.192 4.517 ± 0.219 3.921 ± 0.301 0.779 ± 0.022

**Fresh weight (g)**

**Root** 1.103 ± 0.037 1.288 ± 0.037 1.488 ± 0.028 1.140 ± 0.051 0.418 ± 0.048 0.253 ± 0.007

**Whole plant** 6.282 ± 0.239 6.848 ± 0.266 10.375 ± 0.218

5.658 ± 0.182 4.339 ± 1.166 1.033 ± 0.029

**Shoot** 1.035 ± 0.040 1.520 ± 0.125 1.903 ± 0.134 1.223 ± 0.098 0.880 ± 0.022 0.086 ± 0.002

**Dry weight (g)**

**Root** 0.220 ± 0.027 0.257 ± 0.007 0.297 ± 0.015 0.228 ± 0.010 0.083 ± 0.019 0.028 ± 0.001

**Whole plant** 1.256 ± 0.047 1.777 ± 0.129 2.200 ± 0.135

1.452 ± 0.104

0.963 ± 0.254

0.114 ± 0.003

*Screening and Potential Uses of Contaminated Spent Mushroom (*Pleurotus *spp.)*

*DOI: http://dx.doi.org/10.5772/intechopen.93863*

*Effect of SMS on seedling growth of tomato.*


