TBRI ships banana seedlings to many countries in Asia, Africa, and South America, particularly those hardest hit by Panama disease Race 4. As such, they must respect the quarantine requirements of each country. It would be terrible if the seedlings can resist Panama disease but then bring other terrible diseases such as Banana Bunchy Top or Banana Mosaic viruses.
As such, the seedlings must be kept free from disease. The tissue cultured meristems are gently cultivated in sterilized environments until they are big enough for transplanting. They are hardened and grown out in greenhouses, carefully monitored for any sign of disease. Only when the seedlings are guaranteed to be disease-free are they ready for delivery to farms and plantations. -Julius