**3. Effect of immersion of tomato seeds in** *Pseudomonas* **spp. and**  *Bacillus* **sp. on plant height and number of leaves**

Soaking tomato seeds with *Pseudomonas* spp. suspension and *Bacillus* sp. can increase the growth of tomato plants. This is evidenced in **Table 1**, with the increase in plant height followed by the increase in number of tomato plant leaves. The positive effect of soaking the tomato seeds is obtained on population density of *Bacillus* sp. and *Pseudomonas* spp. which is a minimum of 4 × 10<sup>5</sup> to 12 × 10<sup>5</sup> CFU. The application of *Pseudomonas* spp. suspension with concentration of 5 × 10<sup>5</sup> CFU through seed immersion showed significant difference in tomato plant height, with average tomato height in the first and fourth week at 2.7 cm and 8.5 cm, respectively [8] (**Table 2**).

tomato germination. This indicates that the soaking of tomato seeds with suspensions of bacterium *Pseudomonas* spp. and *Bacillus* sp., or suspense mixture of both types of bacteria is very useful in spurring the growth of tomato seeds when the soaking treatment lasts

PGPR (*Plant Growth Promoting Rizobacteria*) Benefits in Spurring Germination, Growth…

http://dx.doi.org/10.5772/intechopen.78776

21

**Figure 3.** Growth of tomato seeds with *Bacillus* sp. suspense at different seed soaking time periods. *Note*: 1: seeds soaked in distilled water for 20 min; 2–4: seed soaked in *Bacillus* sp. suspension for 10 min; 5–7: seed soaked in *Bacillus* sp.

**Figure 4.** Growth of tomato seeds with *Pseudomonas* spp. suspension at different seed-soaking time periods. *Note*: 1: seed soaked with distilled water for 20 min; 2–4: seed soaked *Pseudomonas* spp. suspension for 10 min; 5–7: seed soaked

*Pseudomonas* spp. suspension for 20 min; 8–10: seed soaked *Pseudomonas* spp. suspension for 30 min.

**Figure 5.** Growth of tomato seeds with a suspense mixture of *Bacillus* sp. and *Pseudomonas* spp. in different seed soaking times. *Note*: 1: seed soaked with distilled water for 20 min; 2–4: seed soaked in *Bacillus* sp. + *Pseudomonas* spp. suspension for 10 min; 5–7: seed soaked in *Bacillus* sp. + *Pseudomonas* spp. suspension for 20 min; 8–10: seed soaked in *Bacillus* sp. +

suspension for 20 min; 8–10: seed soaked in *Bacillus* sp. suspension for 30 min.

*Pseudomonas* spp. suspension for 30 min.

20–30 min.

Tomato plants treated with rhizobacteria have higher productivity caused by the ability of PGPR in spurring plant growth and inhibiting the growth of pathogens. This is in accordance with Hatayama et al.'s [9] study that plants treated with PGPR bacteria have higher yields than controls. One of the PGPR product compounds that inhibit the growth of pathogens is siderophore. Siderophore serves as a systemic booster of plant resistance by inducing plants to form salicylic acid at higher level. Mukaromah [10] stated that salicylic acid acts as a signal transduction gene that activates the systemic inducing receptor in plant tissue. *Bacillus* sp. and *Pseudomonas* sp. are antagonistic microorganisms that are able to suppress soil pathogens by forming antibiotic compounds such as chitinase enzymes that can hydrolyze fungal cell walls and form siderophores and other antibiotics [11, 12].

The growth of tomato seedlings after the soaking treatment with suspensions of *Pseudomonas* spp. bacteria, *Bacillus* sp., and suspense mixture of both types of bacteria with different soaking time for 10, 20, and 30 min are presented in **Figures 3**–**5**. It appears that immersion with sterile water provides the smallest seed growth as compared to other treatments. Soaking tomato seeds for 20–30 min in the suspensions gives better growth for


**Table 1.** T-test results of the higher tomato seedlings on control and soaking treatment with suspensions of *Pseudomonas* spp. and *Bacillus* sp.


**Table 2.** T-test results of the number of leaves of tomato seedlings on control and soaking treatment with suspensions of *Pseudomonas* spp. and *Bacillus* sp.

tomato germination. This indicates that the soaking of tomato seeds with suspensions of bacterium *Pseudomonas* spp. and *Bacillus* sp., or suspense mixture of both types of bacteria is very useful in spurring the growth of tomato seeds when the soaking treatment lasts 20–30 min.

a minimum of 4 × 10<sup>5</sup>

20 Recent Advances in Tomato Breeding and Production

respectively [8] (**Table 2**).

**Leaves of seedlings**

spp. and *Bacillus* sp.

**Seedling height**

> **Control average**

**Control average**

*Pseudomonas* spp. and *Bacillus* sp.

**Treatment average**

**95.00% confidence bound**

1st week 0.5 1.5 0.6 4.923 32.166 0.000 Significant

1st week 2.5 2.7 −0.2 0.740 25.716 0.233 Nonsignificant 1st week 3.9 3.9 −0.2 −0.204 32.195 0.580 Nonsignificant 1st week 5.2 5.1 −0.2 −0.437 30.990 0.667 Nonsignificant

**Table 2.** T-test results of the number of leaves of tomato seedlings on control and soaking treatment with suspensions of

**t df p-value Significance**

**t df p-value Significance**

and form siderophores and other antibiotics [11, 12].

**Treatment average**

to 12 × 10<sup>5</sup> CFU. The application of *Pseudomonas* spp. suspension with

concentration of 5 × 10<sup>5</sup> CFU through seed immersion showed significant difference in tomato plant height, with average tomato height in the first and fourth week at 2.7 cm and 8.5 cm,

Tomato plants treated with rhizobacteria have higher productivity caused by the ability of PGPR in spurring plant growth and inhibiting the growth of pathogens. This is in accordance with Hatayama et al.'s [9] study that plants treated with PGPR bacteria have higher yields than controls. One of the PGPR product compounds that inhibit the growth of pathogens is siderophore. Siderophore serves as a systemic booster of plant resistance by inducing plants to form salicylic acid at higher level. Mukaromah [10] stated that salicylic acid acts as a signal transduction gene that activates the systemic inducing receptor in plant tissue. *Bacillus* sp. and *Pseudomonas* sp. are antagonistic microorganisms that are able to suppress soil pathogens by forming antibiotic compounds such as chitinase enzymes that can hydrolyze fungal cell walls

The growth of tomato seedlings after the soaking treatment with suspensions of *Pseudomonas* spp. bacteria, *Bacillus* sp., and suspense mixture of both types of bacteria with different soaking time for 10, 20, and 30 min are presented in **Figures 3**–**5**. It appears that immersion with sterile water provides the smallest seed growth as compared to other treatments. Soaking tomato seeds for 20–30 min in the suspensions gives better growth for

> **95.00% confidence**

1st week 0.5 2.7 1.8 8.589 49.714 0.000 Significant 2nd week 3.0 5.0 1.6 8.596 41.209 0.000 Significant 3rd week 4.3 6.1 1.2 5.612 27.993 0.000 Significant 4th week 7.8 8.4 0.2 2.363 30.688 0.012 Significant

**Table 1.** T-test results of the higher tomato seedlings on control and soaking treatment with suspensions of *Pseudomonas*

**Figure 3.** Growth of tomato seeds with *Bacillus* sp. suspense at different seed soaking time periods. *Note*: 1: seeds soaked in distilled water for 20 min; 2–4: seed soaked in *Bacillus* sp. suspension for 10 min; 5–7: seed soaked in *Bacillus* sp. suspension for 20 min; 8–10: seed soaked in *Bacillus* sp. suspension for 30 min.

**Figure 4.** Growth of tomato seeds with *Pseudomonas* spp. suspension at different seed-soaking time periods. *Note*: 1: seed soaked with distilled water for 20 min; 2–4: seed soaked *Pseudomonas* spp. suspension for 10 min; 5–7: seed soaked *Pseudomonas* spp. suspension for 20 min; 8–10: seed soaked *Pseudomonas* spp. suspension for 30 min.

**Figure 5.** Growth of tomato seeds with a suspense mixture of *Bacillus* sp. and *Pseudomonas* spp. in different seed soaking times. *Note*: 1: seed soaked with distilled water for 20 min; 2–4: seed soaked in *Bacillus* sp. + *Pseudomonas* spp. suspension for 10 min; 5–7: seed soaked in *Bacillus* sp. + *Pseudomonas* spp. suspension for 20 min; 8–10: seed soaked in *Bacillus* sp. + *Pseudomonas* spp. suspension for 30 min.
