Study on transpiration rates of indoor decorative plants.

Choosing certain indoor decorative plants at appropriate sizes might help adjust indoor air humidity level. This research aimed to study transpiration rates of 6 popular indoor decorative plants, Neoregelia carolinae, Sansevieria trifasciata 'Hahnii', Epipremnum aureum, Dieffenbachia amoena, Spathiphyllum floribundum 'Sensation' and Zamioculcas zamiifolia for 24-hour period using portable photosynthesis system model LI-6400. The study was done in office room of Center of Thai-French Cooperation on Higher Education and Research, Kasetsart University, Bangkok during June to October 2009. The results showed that day-time leaf respiration rates and stomatal conductances were greater than night time. Spathiphyllum floribundum 'Sensation' had the greatest averaged transpiration rate. In 24-hour period, transpiration of six decorative plants ranged from 0.2 to 14.6 mol H2O per plant. Spathiphyllum floribundum 'Sensation' transpired the most due to its larger size and greater leaf transpiration rate. Day-time transpiration accounted for 72-91 percent of daily transpiration while night-time transpiration accounted for only 9-28 percent.