Photosynthesis and transpiration rate of Phalaenopsis at different altitudes in Magelang Regency for flowering induction

Abstract

Vernalization is very important in Phalaenopsis, but studies on photosynthesis and its implications still need to be completed. The study's objective was to analyze the effect at different altitudes on the photosynthesis rate at the time of flowering induction and after the appearance of flowers. The research was carried out at Nambangan Orchid. A non-factorial randomized block design was used in this study with four blocks. The treatments were K1 (Sidomulyo village at an altitude of 400 m), K2 (1000 m), and K3 (Kaponan village at an altitude of 1250 m). The altitude has a very significant effect on the photosynthesis rate (Pn), Photosynthetically Active Radiation (PAR), and transpiration rate at Phalaenopsis plants before the spikes appear, the time of spike appearing, flower diameter, number of flower buds/spike, flower color, and leaf color. The most intense flower color is found at an altitude of 1250 m. The flower diameter and the number of flower buds/spikes were mainly obtained at an altitude of 1000 m. The altitude does not affect the photosynthesis rate, PAR, and transpiration parameters when the plant is flowering. The altitudes at 1000 m and 1250 m did not differ in parameter the time of spike appearing but were significantly different at an altitude of 400 m. Local wisdom by transferring Phalaenopsis plants to an altitude of 1000 m and 1250 m for induction of flowering has been proven by the results of photosynthesis measurements, which impact the quality and quantity of Phalaenopsis flowers.