Page 123 - EER-2-3

Explora: Environment
and Resource Low-cost hydroponic for chili production

1 h. Sterilized seeds (n = 100) were placed in plantation necessary by adding water or nutrients. Both hydroponic
26
trays containing coco peat as the growth medium and were systems were maintained indoors under natural sunlight
watered periodically. A control group was maintained on an open laboratory balcony at Adamas University,
by planting seeds in soil obtained from a local nursery. with a temperature of 22–27°C, relative humidity (RH) of
Germination percentage was recorded through regular 75–80%, and light intensity of 1,000–3,000 µmol/m /s for
2
observations. After 10 days, healthy seedlings (4–5 cm approximately 11–13 h/day. A soil-based system (n = 20)
in length) were randomly selected from both plantation served as the control (Set III) (Figure 1D).
trays (coco peat and soil) to assess the seedling vigor index In summary, the experiment consisted of three
(SVI-I), calculated using Equation I: 27 treatments:
SVI – I = Seedlinglength × Germinationpercentage (I) • Set I: Low-cost hydroponics using plastic bottles
(22–27°C, RH 75–80%, 1,000–3,000 µmol/m /s for
2
2.3. Experimental setup and plant growth 11–13 h/day
monitoring • Set II: Conventional hydroponics using a nutrient
Discarded plastic bottles of various sizes were thoroughly reservoir, net cups, and an electric air pump (same
cleaned and repurposed as nutrient reservoirs to conditions as Set I)
construct a low-cost, non-circulating hydroponic system • Set III: Soil-grown plants serving as control (same
(Set I) (Figure 1A and B). A conventional hydroponic conditions as Set I).
system, similar to those commonly used in commercial Data were recorded for shoot height (cm), days to first
cultivation, was prepared using an opaque container as flowering, days to first fruiting, days to full fruit maturation
the nutrient reservoir, equipped with an electric air pump (red-ripe stage), fruit weight, and total yield per plant.
for aeration and plastic net cups (Set II) (Figure 1C). The Fruit development was monitored visually, and red, fully
nutrient solution was prepared by mixing all the required matured fruits were harvested. Measurements included
chemicals (Table A1) following the protocol by Hoagland individual fruit weight and total yield per plant.
and Arnon. 28

Forty randomly selected, healthy seedlings germinated 2.4. Comparative analysis of stress response
in coco peat were transferred to the hydroponic systems: A comparative study was performed using randomly
20 to Set I and 20 to Set II. In Set I, seedling roots were selected leaves from fruit-bearing plants across all three
immersed directly in the nutrient solution, while the stem experimental sets. The following assays were conducted:
was secured at the bottle opening with cotton plugs. In • H O content: Leaf tissue was extracted in
2
2
Set II, the roots were suspended in the nutrient reservoir, 100 mM potassium phosphate buffer containing 5 mM
whereas the aerial parts were supported above the lid using potassium cyanide, and absorbance was measured at
net cups. Electrical conductivity (EC) and pH of the nutrient 560 nm 30
solution were maintained at 1.4–1.8 mS/cm and 5.8–6.5, • Lipid peroxidation: Malondialdehyde (MDA) content
29
respectively. These parameters were monitored using was quantified, and absorbance was read at 532 nm 31
commercially available pH paper and a portable EC meter • Superoxide dismutase (SOD) activity: Measured
(AP-IS11A058FBA, Aptechdeals, China) and adjusted as at 540 nm using p-nitro blue tetrazolium chloride

A B C D

Figure 1. Indoor farming systems: (A) schematic diagram of the low-cost bottle hydroponic system; (B) Set I - plant grown in low-cost hydroponics using a
plastic bottle; (C) Set II - conventional hydroponics with nutrient reservoir, net cups, and electric air pump; (D) Set III - soil-grown control plants. Harvest
fruits from each system are shown in the corresponding insets.

Volume 2 Issue 3 (2025) 3 doi: 10.36922/EER025250050