This year I wanted to plant 50 banana/plantain trees but balked at prices from 5-30$ USD each. I began looking at how to grow plants myself and found a way which many people seem unaware of.
I'm going to describe to you how to obtain large quantities relatively disease and pest free banana or plantain suckers for a very low cost and at a fast high rate of multiplication. Macropropagation differs from laboratory tissue culture Micropropagation but obtains a similar result at very low cost using common materials anyone can obtain.
This technique was developed in Africa where plantain is a staple food source but many of the varieties have very low multiplication rates. The lack of sufficient suckers for planting made it difficult for small farmers to scale up their production quickly to meet food needs and market demand, even if they had space to grow more. The technique was delevoped by Dr. Moise Kwa of Cameroon for his PhD. Thesis in the 1990's
The method is called PIF (Plants Issus de Fragments de Tiges-Fr.)(plantlet from stem fragments-Eng.) and uses the fact that hundreds of dormant buds lie beneath the leaf sheaths of every banana corm. These dormant buds lie waiting to grow but are inhibited by hormones produced in the plants apical growing tip (central bud). Using PIF techniques you can awaken these dormant buds and produce up to 100 banana plantlets from just one one sword sucker. Additionally, most pests and diseases will be eliminated by sterilization during the process yielding healthy plantlets ready to grow well.
First and foremost, you need to select the healthiest sword suckers as 'mother' plants. They should be as large as possible and show no signs of disease. I would recommend sourcing these from an existing plant growing in a recently planted field with no signs of disease and if possible from tissue cultured plantlets. A minimum size would be 6" (150 mm). Learn how to identify common banana/plantain diseases like Sigatoka, Panama. Bunchy top, etc..
The sword sucker corms will be dug carefully from the mother plant, then trimmed of all roots leaving only bare white flesh at the base and cut closely at the top just above the ring surrounding the outer leaf sheath. This removes nematodes and their eggs and exposes possible corm weevil tunnels and will begin reducing the pest load of the material. Then a pot of boiling water is prepared and the corm is put into boiling water for ONLY 30 seconds. Alternatively, corms can be soaked in pesticides and fungicides or for 60 seconds in a 10:1 water:household bleach solution. This treatment eliminates virtually all pest/disease on the surface of the material in much the same way a laboratory treats tissue culture before micropropagation. I used the bleach method and rinsed the bleach thoroughly afterwards.
Once sterilized, you begin to peel away leaf sheaths one by one towards the center by cutting around each sheath just above where each sheath attaches to the corm. As you do this you will notice that each one has a "V" shape on one side and there is a dormant bud at the base of the "V". This would eventually form a sucker, but just as the center of the plant suppresses sucker growth, each one of these sucker buds suppresses growth of 10 dormant buds lying around it. These buds must be destroyed to allow the many others to activate, so destroy each of them them by deep cross cutting using a knife. Keep peeling off leaf sheaths one by one working inwards and killing buds at the "V"'s until you cannot go further inwards. The result will look like a low cone shape with "X" marks every 180 degrees where you killed buds. Finally, destroy the central bud by cutting deeply into the center and removing all of it with a knife.
Once the corms are processed, plant them in a sterile humidity controlled environment. This can be fabricated using various materials wood/brick/plastic and able to hold 12" (300 mm) deep growing medium and have a height of 2 ft. (600 mm) to allow plant growth. It should be enclosed in plastic to hold humidity and at about 50% shade and be kept warm even hot 90-100F (30-36C) to stimulate growth. I used 30 gallon black plastic nursery pots covered by clear polythene sheeting to hold 3 corms.
Growing media needs to be as sterile as possible to prevent fungal disease. This can be done by steam heating sawdust, cacao or nut husks or composts. Solarization of moist medium for 30 days in plastic is another method. I used peat moss which had been solarized.
Growth should be visible in 30 days. I was able to harvest 10 suckers from each corm by 60 days. They need to be carefully cut off the corm leaving a small piece of corm and with at least 3 roots to be potted up. Another 30 days in shade and hardening off for 2 weeks and the plants are field ready. Professionals have been able to carefully kill off the first set of sucker growth which further
"re-activates" the corm to produce up to 100 plantlets from each corm.
I'll post some written descriptions with pictures and videos. Good luck and if anyone has questions or improvements let me know.