Smart Agriculture for Urban Farming

Introduction

The country’s total food import bill is continuously increasing from RM3.5 billion in 1985 to RM7.7 billion in 1995 and RM 10.0 billion in 1997 [1]. Although plants survive when subjected to the day-to-day inconsistent weather, however, they seldom reach their genetic potential in nature. Consistent, predictable plant growth can be achieved only when environmental conditions are consistent from day to day. Individual environmental parameters can be held steady to provide consistent growth, therefore integrating and coordinating control of the various environmental parameters will be an effective and less expensive means to optimize total production cost while still ensuring consistent growth and productivity of agricultural yields. Photosynthesis is the process whereby plants use light energy to convert carbon dioxide and water to glucose sugar and oxygen gas through a series of reactions. Photosynthesis is carried out in the chloroplasts of plant cells using the green pigment chlorophyll. The glucose produced is converted into starch. Starch is a polymer made up of repeating glucose units. The overall equation for photosynthesis is Carbon Dioxide + Water + (Light) = Glucose + Oxygen The equation shows how plants combine carbon dioxide and water with the aid of light energy to form sugar. Some of these sugars are converted into complex compounds that increase dry solid plant substances for continued growth to final maturity. However, when the supply of carbon dioxide is cut off or reduced, the complex plant cell structure cannot utilize the sun’s energy fully and growth or development is curtailed or retard. With Global warming and unpredictable weather, it is imperative to find alternative solutions to address this issue. Some researchers have already adopted greenhouse and artificial lighting technology to protect, help and speed up the plants’ growth such as Light Emitting Diode or LED [2-5]. While sunlight comprises the entire spectrum of light, an LED light source can be controlled to stimulate different photoreceptors in the plant. For example, blue light can stimulate phototropins and cryptochromes, and red light stimulates phytochromes which regulate flowering. Chlorophyll molecules absorb blue and red wavelengths most efficiently while the green and yellow wavelengths are reflected or transmitted as they are not as important in the photosynthetic process. By limiting the amount of color given to the plants, they can still grow normally and taste the same as those raised in white light. The use of artificial lightings namely LEDs enables researchers to eliminate other wavelengths found within normal white light, thus reducing the amount of energy required to power the plant growth lamps. PAR or Photosynthetically Active Radiation is the spectral range between 400nm-700nm in which plants use for photosynthesis. PAR is expressed in micromoles, which is a measurement of the photosynthetic photon flux density of light, per square meter per second. The red and blue light which fall within this range best drive photosynthetic metabolism [2,3]. These light qualities are particularly effective in improving the developmental characteristics associated with autotrophic plant growth habits. In addition, photoperiod (the adjustment of light and dark periods) and light quality (the adjustment of the red, blue and far-red light ratio) also have decisive impacts on photomorphogenesis. The superimposed pattern of luminescence spectrum of the blue LED (450 – 470 nm) and red LED (650 -665 nm) corresponds well to the light absorption spectrum of carotenoids and chlorophyll. LEDs are the first light source to provide the capability of true spectral composition control, allowing wavelengths to match to plant photoreceptors to optimize production as well as to influence plant morphology and composition. They are easily integrated into digital control systems, facilitating complex lighting programs like varying spectral composition over the course of photoperiod or with plant development stage. While the process of photosynthesis does not require continuous light of full spectrum, LEDs can produce sufficient photon fluxes of a specific wavelength on and off rapidly. Such mechanism of photosynthesis coupled with the solid-state characteristics of LEDs constitutes two ways of energy saving (cutting out unnecessary spectrum segment and turning off the light periodically) on top of the LEDs’ low power consumption. The research works on the use of LED as a light source for photosynthesis process and will focus on identifying the color spectrum suitable for the process. Most researchers reported on the alternative form of light source for the plant emphasizing on the LED development without due consideration to influence on the plantation itself such as the growth, taste, life cycle, yields and etc. Experimental analysis done on lab work scale were reported in [2,4]. Light Saturation Point is the point at which plant receives more light than they utilize and if these plants receive much over that, they can reach the point of light saturation. In some instances, plants have been observed growing slower when exposed to excess amounts of light, vs growing in their optimal range. For this reason, it is imperative to supply the plants what is optimal light for their species. In this research, we focus on determining the optimum LED light spectrum suitable for the superior growth of plantations in the greenhouse under the influence of tropical climates. Finally, verification and validation of the results will be carried out on selected plantations and greenhouses.

Executive Summary of The Project

Overall Project Objectives

Our Funder: 

UTM Research University Grant Scheme (RUGS). Amount: MYR200,000

MOHE Fundamental Research Grant Scheme (FRGS). Amount: MYR44,000.00

Back      Next