**4. Mineral, organic and synthetic substrates used in the substrate cultivation system of cucumbers**

As mentioned in the introduction different substrates can be used for cucumber cultivation in substrate culture systems. In principle, most substrates are suitable for successful cucumber growing, if adequately supplied with water and plant nutrients.

In one experiment were compared substrates from the three groups (**Table 1**), because the ecological aspects are becoming more and more important when choosing substrates, as well the economic efficiency is important. Substrate were filled in containers or available as mats, between 8 and 9 liters of substrate were available per plant. The aim was to use substrates with different physical and chemical parameters (**Table 3**).


Comparing the four substrates used, the significantly highest total yields of cucumbers were obtained in the variants 'organic substrate'. The differences in crop

#### *Cucumber Economic Values and Its Cultivation and Breeding*


The objective of this experiment was to investigate the development and yield of cucumber grown on sheep wool slabs in comparison with peat and coconut fiber slabs as well as Rockwool slabs and perlite in containers. Different sheep wool slabs in size and added components were tested, the highest stability was obtained with

*Growth Promoting and Stabilizing of Cucumber Plants Cultivated in Soilless Cultivation…*

• Does sheep wool slabs have appropriate physical parameters for cucumber

• How do the physical properties change in comparison with other organic and

• How do biostimulators influence cucumber plant growth in the investigated

Sheep wool slabs used in this experiment were compared with the following

• Coconut fiber (width 25 cm, length 100 cm, height after wetting 9 cm) from

• Peat slabs 'GroBoard' (width 20 cm, length 100 cm, height after wetting 9 cm)

In this experiment fifty percent of the cucumber plants of each substrate variant were treated three times with a biostimulator solution containing 0.08% K-Humate

) of *Bacillus subtilis* FZB 24®. To the plants were applied 20 ml of this

• Perlite, average grain size between 0.06 mm and 1.5 mm, properties see

• Rockwool slabs (width 20 cm, length 100 cm, height 7.5 cm) from the

(Fa. Humintech), 0.2% Lactofol (O) (Fa. ECOFOL) and a spore suspension

solution three times in weekly intervals starting with first treatment in 6–7 leaves stage, after transplanting. Plants of *Cucumis sativus* L. 'Indira' were used for the experiment. The experiment was conducted during two cultivation periods, first from November until April and second from June until November in the next year.

*5.1.1 Effects of biostimulators growing cucumbers in mineral and organic substrates*

For the soilless cultivation of the cucumber plants substrates was selected with different physical properties (**Table 5**). In general substrates for cucumbers should have high air capacity with a range between 20 to 40%, during the cultivation time often the air capacity is decreasing very much and water capacity increasing, therefore a certain stability is necessary in this regard. Sheep wool had the highest air capacity with about 70%, while peat had the lowest air capacities with 18%. The peat slabs were pressed to reduce the volume for the transport, the expansion of the slabs needs time. Because the low water capacity of sheep wool at the beginning, a water reserve is missing in case of low water availability. It seems that sheep wool and perlite requires a higher and more stable supply with nutrient solution than the other substrates. The physical properties after second use of the substrates

sheep wool slabs in combination with coconut fibers.

*DOI: http://dx.doi.org/10.5772/intechopen.96536*

mineral substrates?

the company 'Dutch Plantin'.

company 'Pargro' from Finland.

from the KEKKILÄ Oyj company Finland.

**Table 3** was filled in Container with 7 L volume.

substrates?

substrates [12]:

(10<sup>7</sup> cfu ml<sup>1</sup>

**73**

In this experiment following questions were investigated:

cultivation and how many months they can be used?

*WC = water capacity; AC = air capacity; PV = pore volume; CEC = cation exchange capacity. \* [1].*

#### **Table 3.**

*Physical and chemical characteristics of substrates used in experiments with cucumber growing in substrate culture.*


#### **Table 4.**

*Yield of greenhouse cucumber in mineral, artificial and organic substrate (kg/m<sup>2</sup> ).*

yield of the investigated substrates in the examined months (**Table 4**) can be due, because different growing conditions, as:


The development of the leaf area of cucumber plants was examined for the variants with rockwool mats, urea foam and perlite. The following leaf areas were determined as the mean of all measuring dates: in rockwool 8215 cm2 , in urea foam 7889 cm2 , and in perlite 7438 cm2 .
