Influence of IAA, TDZ, and light quality on asymbiotic germination, protocorm formation, and plantlet development of Cyrtopodium glutiniferum Raddi., a medicinal orchid

Abstract

We investigated the influence of light quality on in vitro germination and protocorm formation, and the effect of indole-3-acetic acid (IAA) and thidiazuron (TDZ) on proliferation of protocorm-like bodies (PLBs) and development of plantlets of Cyrtopodium glutiniferum Raddi. Germination was faster under white and blue light, and highest under green light. The protocorm developed more rapidly under white, blue, and green light. Continuous darkness delayed seed germination and reduced protocorm formation. Among the plant growth regulators (PGRs) tested for multiplying PLBs, shoots, and roots from protocorms, IAA proved to be superior. TDZ was effective in inducing PLB fresh weight accumulation, but not morphogenesis, unlike IAA. This study indicated that C. glutiniferum seedlings can be produced in vitro using asymbiotic seed germination techniques. High germination rate and protocorm yield can be obtained by initially cultivating C. glutiniferum seeds on medium without growth regulators under white light, or under white light supplemented with green or blue light. This culture system complies with commercial and conservation requirements for rapid and low-cost propagation.

In vitro culture and acclimatization of Cattleya xanthina (Orchidaceae), an endangered orchid of the Brazilian Atlantic Rainforest

“…5b), which confirms the action of auxin on adventitious root formation by pericycle cells, responsible for initiating the processes of cell division and expansion (Casimiro et al 2001). Similar results were observed in Cyrtopodium glutiniferum Raddi (Vogel & Macedo 2010); in this study all auxin treatments resulted in the production of plants with larger roots when compared to treatments containing cytokinin only. The proposition of Krouk et al (2011), that increased endogenous auxin levels promote root development thus enhancing absorption of nutrients, including nitrogen, which has a primary role in the composition of the chlorophyll molecule, was apparently not effective in C. xanthina plants.…”

Functional analysis of an iaaM gene in parthenocarpic fruit development in transgenic Physalis pubescens L. plants

“…Thidiazuron (TDZ) has been shown to enhance the frequency of shoot organogenesis in cotyledon explants (Vogel and Macedo 2011;Thirukkumaran et al 2009), which is in agreement with our findings as well. For P. pubescens, maintaining shoot regenerants on SEI medium containing TDZ for periods longer than 3-5 weeks resulted in the recovery of short and compact shoots (\1 cm in length, Fig.…”

Effect of light quality on Tabebuia rosea seed germination

“…However, it seems that the main effect of blue light is to promote germination of many herbaceous species (e.g. Alysicarpus rugosus (Chaughtai et al 1983), Amarunthus tricolor (Singhal et al 1983) and Cyrtopodium glutiniferum (Vogel & Macedo 2011) (Chaughtai et al 1983). On tropical tree species, blue light increases germination percentage (e.g.…”