EFFECT OF LIGHT SPECTRUM ON CACTUS GERMINATION AND GROWTH

Abstract

The purpose of this research was to study the effects of light spectra of LED light sources and sunlight with shading on germination and growth of Gymnocalycium and Astrophytum asterias cactus seeds. Cactus seeds were planted in a closed system with 10 seeds per pot under the light of a plant grow lamp, a lamp that produces white, green, blue, and red light. This included seeding experiments under sunlight and with 60% silver sunshade net of 1, 2, and 3 layers. The growth photographs were recorded for analysis to determine the diameter of the cactus. It was found that under the light from the plant-grow lamp and the white-light lamp, the germination rate of both cultivars was high, the growth was rapid in the first period and the growth slowed down in the latter. The green-light and blue-light lamps had low seed germination rates and slower growth. The red-light lamp had high germination rates but had abnormally elongated stem growth. The experiments planted under the sunlight without shading showed low germination rate and poor growth. However, germination and growth rates were higher when planted under 2 and 3 layers of sunshade net. From the research,
it was found that under the sunlight optimal conditions for the highest germination and growth are 2 layers of 60% silver sunshade net. It can be grown indoors using artificial LED lights which are used as both plants grow light and white light. It can be utilized in cacti planting to increase its value from high yield and beautiful stem quality.