The inclusion of the Internet of Things (IoT) in indoor agricultural systems has become a fundamental tool for improving cultivation systems by providing key information for decision-making in pursuit of better performance. This article presents the design and implementation of an IoT-based agricultural system installed in a plant growth chamber for hydroponic cultivation under controlled conditions. The growth chamber is equipped with sensors for air temperature, relative humidity (RH), carbon dioxide (CO2) and photosynthetically active photon flux, as well as control mechanisms such as humidifiers, full-spectrum Light Emitting Diode (LED) lamps, mini split air conditioner, pumps, a Wi-Fi surveillance camera, remote monitoring via a web application and three Nutrient Film Technique (NFT) hydroponic systems with a capacity of ten plants each. An ATmega2560 microcontroller manages the smart system using the MODBUS RS-485 communication protocol. To validate the proper functionality of the proposed system, a case study was conducted using lettuce crops, in which the impact of different nutrient solution concentrations (50%, 75% and 100%) on the phenotypic development and nutritional content of the plants was evaluated. The results obtained from the cultivation experiment, analyzed through analysis of variance (ANOVA), show that the treatment with 75% nutrient concentration provides an appropriate balance between resource use and nutritional quality, without affecting the chlorophyll content. This system represents a scalable and replicable alternative for protected agriculture.
As an alternative to confronting the actual challenges in the conventional agriculture, Controlled Environment Agriculture (CEA) and hydroponics arise as sustainable alternatives, allowing for an efficient use of resources during green-leaf crop production. Considering a Nutrient Film Technique (NFT) hydroponic wall-system and two different ranges of light spectra provided via LED technology, this study evaluated their impact on the yield and efficiency during the cultivation of Swiss Chard crops (Beta vulgaris var. cicla) based on an analysis of morphological and nutritional characteristics. The experiment was developed in a growth room chamber, which was monitored and controlled under an IoT scheme, mainly focusing on the lighting treatments; treatments T1 and T2 were defined with the LED Barina 42W and LED MURFURN 70W, correspondingly. The results show no significant differences between both treatments in most morphological cases; however, the foliar area was significantly larger in treatment T1 than in treatment T2. Additionally, the nutritional quality of treatment T1 showed higher concentrations of carbohydrates, proteins, minerals, Ca, and K. Conclusively, the light spectrum composition provided by the lighting system influences the chard physiology, favoring the nutrient concentration under red–blue spectrum combinations.