The majority of the CO 2 absorption is achieved during the dark night. However, there is some CO 2 uptake in the late afternoon just before the dark period begins. Dr. Kenneth Leonhardt of the Department of Tropical Plant and Soil Science at the University of Hawaii at Manoa gave an excellent speech on potted dendrobium orchids. He indicated that the University of Hawaii has done breeding on pot dendrobium orchids of short statue and has introduced 15 hybrids. Most of them are triploids or tetraploids, usually with one amphidiploid parent.
Amphidiploids are tetraploids with a complete diploid genome complement from each species parent.
This condition causes the amphidiploids to breed as if they were a species. When an amphidiploid is crossed with a species or another amphidiploid, the hybrid progeny population is relatively uniform from seed. Pictures of several hybrids that he showed certainly demonstrated the showy flowers and uniformity of these dendrobium pot plants. All of the University of Hawaii orchid hybrids and cultivars are contracted to commercial propagators for mass production. It is very important to keep in mind that medium interacts with the applied nutrients to affect orchid growth.