Amin Reza Jamshidi; Ahmad Ghazanfari Moghaddam; Fatameh Mozafari Ghoraba
Abstract
The development of aeroponic cultivation technology has led to more efficient use of water and plant nutrients for producing high quality agricultural commodities. In this research, cucumbers were grown in columnar aeroponic systems for nine weeks and the effect of spraying rate and spraying duration ...
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The development of aeroponic cultivation technology has led to more efficient use of water and plant nutrients for producing high quality agricultural commodities. In this research, cucumbers were grown in columnar aeroponic systems for nine weeks and the effect of spraying rate and spraying duration on the cucumber average yield and water usage efficiency were investigated. The experiments were performed using factorial experiment based on completely randomized designs. The spraying rate had three levels of 125, 250 and 375 mL/min, and the spraying durations were 10, 15 and 20 min. During the experiment, the spraying pumps were turned off for 15 min between each spraying time. Then, the two factors were simultaneously optimized using response surface methodology to maximize fruit yield and water usage efficiency. The ANOVA results showed that both responses were significantly affected by the main effects of the factors (α = 0.01) and by their interaction effects (α = 0.05). The comparison of first and second-order models to show the average yield and water usage efficiency as functions of sparing rate and sparing time indicated that the second-order models fitted with higher accuracies (R2> 80%) to the experimental data than the first-order model. Simultaneous optimization showed that the most suitable spraying rate was 233.37 mL/min and for the spraying duration, it was 16.06 min. At the optimum conditions, the average yield per plant yield was 2.96 kg and the water usage efficiency was 110.37 kg/m3.
Amin Reza Jamshidi; Ahmad Ghazanfari Moghaddam; Ahmad Reza Ommani
Abstract
Aeroponic planting is proved to be the one of the most efficient growing environments for many vegetable crops. In this technique, plants are cultivated in absence of soil and the required nutrients are directly supplied to the roots through a fogging system. In modern sprayers, water is atomized by ...
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Aeroponic planting is proved to be the one of the most efficient growing environments for many vegetable crops. In this technique, plants are cultivated in absence of soil and the required nutrients are directly supplied to the roots through a fogging system. In modern sprayers, water is atomized by means of ultrasound waves. The aim of the present study was to investigate the effect of ultrasound waves on the nutrient solution and on yield and some yield components of tomato grown in a vertical aeroponic planting system. The investigation was conducted using a 3×3 factorial experiment based on a completely randomized design. The considered factors were ultrasonic frequency at three levels of 50 kHz, 107 kHz and 2.1 MHz and the fogging duration at three levels of 10, 15 and 20 min. The results indicated that, at frequency of 50 MHz, the nutrient solution had the lowest EC equivalent while the pH of the nutrient solution reached its highest value at 2.1 MHz. Generally, both EC and pH value of the nutrient solution were elevated by increase in the wave frequency, but they did not show a definite trend by changes in fogging duration. The ANOVA indicated that the interaction effect of the ultrasound frequency and fogging period had significant effect on the plant height, root weight and length, fruit weight, fruit length, plant yield and system performance. In general, the measured yield components decreased as frequency of the waves increased and the best results were obtained at 50 kHz frequency and 15 min fogging period.
