A classroom exercise in hand pollination and in vitro asymbiotic orchid seed germination

摘要

While many scientific reports on orchid seed germination provide germination protocols, few provide concise descriptions of plant selection, hand pollination, and asymbiotic seed culture for use in classroom exercises. Another major limitation for conducting orchid seed germination exercises is the availability of seeds or flowers to pollinate. In this paper, we outline an efficient and reliable classroom exercise using the orchid Spathoglottis to demonstrate hand pollination and subsequent asymbiotic seed germination. Flowers of S. parsonii are hand pollinated and subsequent seed capsule development is carefully monitored. Hand pollination of the orchid flower provides an opportunity to discuss floral morphology and associated reproductive biology. Capsules are harvested 30 to 40 days after pollination, prior to capsule dehiscence. Spathoglottis kimballiana seed capsules are surface sterilized, seeds excised, and then sown on P723 Orchid Seed Sowing Medium. Germination occurs quickly and large seedlings ready for greenhouse acclimatization develop within 4–6 months.