The Effect of Root Zone Cooling on the Growth of Lettuce Plants (Lactuca sativa L.) in a Hydroponic System with Different Temperature Treatments
Joko Prasetyo, Gunomo Djojowasito, Wiryaningtyas Setya Winahyu, Annisa Noor Sasmita

Universitas Brawijaya

Abstract

Climate and weather in Indonesia pose significant challenges to improving vegetable crop productivity. Hydroponics is one cultivation system used to overcome these issues by allowing the regulation of environmental conditions around the plants. In addition to proper water and nutrient management, temperature is a crucial factor to consider in hydroponic cultivation. High environmental temperatures can disrupt morphogenesis and hinder plant growth. Root zone cooling technology has emerged as a solution to maintain low temperatures in the root area, aiming to stimulate cell elongation and enhance the productivity of lettuce plants (Lactuca sativa L.). The objective of this research is to design a wick hydroponic system with the addition of root zone cooling treatment and compare the effects of temperature variations and cooling duration on lettuce plant growth. A simple cooling system composed of several components, including the Peltier TEC 12706, temperature sensor, and controller XH W109, was utilized in this research. The research was conducted using an experimental research method. The treatments applied in this study involved variations in cooling temperatures, which included 15, 20 and 25 degrees Celsius. The cooling treatment was conducted for 4 hours, starting from 12.00 PM to 4.00 PM Western Indonesia Time (WIB). Based on the research, the best results were obtained from the treatment at 20 degrees Celsius, where the average plant height was 20.45 cm, the average leaf count of 8 leaves, the average leaf greenness index was 16.44, and the leaf area was 104.31 cm2. This study shows that the cooling treatment at 20 degrees Celsius has a positive effect on lettuce plant productivity compared to the control plants.

Keywords: Productivity, root zone cooling, hydroponic, Thermo-Electric Cooler (TEC)

Topic: Agricultural Engineering