The Northern Philippines Root Crops Research And Training Center based at the Benguet State University in La Trinidad is doing great service to potato planters in the Condillera. That as by providing the farmers with disease-free planting materials that result in better yields.
The technique is called rapid multiplication. The planting materials are two-week-old cuttings that are rooted in a mixture of sterilized soil and carbonized rice hull. These are supplied to farmers at a cost of one peso per rooted cutting.
In about four months from planting in the field, the plants will be ready for harvest and the farmers usually get 18 tons per hectare. If the growing conditions are good, the yield could reach as high as 30 tons, according to Grace Backian, coordinator of the extension service of NPRCRTC.
How do they produce the disease-free rooted cuttings? First, the plants that serve as the source of cuttings for rapid propagation are produced at the tissue culture laboratory. From the lab, they are planted in black plastic community pots in which they are allowed to grow as mother plants.
From the mother plants, shoot cuttings with a couple of leaves are taken and planted in community plastic pots of 105 cuttings which when sold to the farmers are considered as 100 pieces per pot. It is really a rapid multiplication technique because in just 14 days from sticking the cuttings in the propagation medium, the cuttings are already rooted and right for planting in the field.
The varieties being multiplied are the Igorota and Granola. The Igorota is the number one choice of farmers because they like the round shape and mealy consistency of the tubers. It is also highly suitable for making potato chips.
The other favored variety is the Granola which also has round tubers that are mainly for table use. The Granola is also earlier maturing than the Igorota. Tubers can be harvested in just 75 days from planting in the field.
Right now the NPRCRTC researchers are evaluating 22 varieties from the International Potato Center. This will be released to the farmers for their own trial so they will decide for themselves which one is suitable for their purposes.
One other way of growing potato is to plant tubers instead of the rooted cuttings. This is usually practiced where water supply is unpredictable. The cuttings may not survive if water is in short supply during the early stages of growth. It is safer to plant tuber seed pieces. But there is the risk that the planting materials may be disease-infected.
Aside from NPRCRTC, there are private nurserymen who have been taught how to produce rooted cuttings thru rapid multiplication. They buy their mother plants from the research center from which they source their cuttings. They pay P10 per mother from which they can get about 60 cuttings. They could get more if the mother plants are properly maintained.