Iron and calcium as micronutrients: AARON HICKS assesses the importance of iron and calcium to healthy orchid growth in vitro, and examines the effects of nutrient deficiency

摘要

TWO MICRONUTRIENTS ARE OF particular importance to the mineral nutrition of orchids in vitro. While their chemical properties may have relatively little in common, together they are responsible for a sizeable number of issues experienced by orchids grown in sterile flask. Some years ago, when I first started growing orchids in sterile culture, I found the most remarkable growth came from stanhopeas. In fact, some of the most robust plants to grow in sterile culture belong in the Stanhopeinae - peristerias, gongoras, paphinias, coryanthes and stanhopeas themselves. If the seeds are viable, the resulting plants grow with remarkable strength on a variety of media. (As an aside, they may grow a bit too strongly, so that the usual variation in growth rates may result in one or two goliath seedlings in flask while the remainder are too small to be deflasked with a good chance of survival. As noted in a previous article, opening the flask in a sterile workspace and removing the largest plants while allowing the balance to remain and mature will improve yields.)