All about potatoes.pdf - Vegetableipmasia.org

4.
SEED PREPARATION AND PRODUCTION
by pests and disease. Another important characteristic to pay attention to when
sorting is the uniform length of the shoots. In the field, seed potatoes that have been
damaged in transport should also be separated out.
4.5 Treatment of seed tubers
Before they are put into storage, seed tubers should be cleaned of any soil sticking to
the tuber, as the soil can contain disease. Clean tubers by washing them, or airing
them, spreading them out in the storage area. Any soil stuck to tubers will fall off by
itself. Tubers should be turned over at least once a day to help them dry more
quickly.
To prevent potato tuber moths from infesting the tubers, many farmers apply
chemical insecticides to seed potatoes in storage. This practice is very hazardous to
the farmers’ health, even more so when the seed potatoes are stored in their homes.
As an alternative in areas with severe infestation, farmers can use the biological
insecticide Granulosis Virus (GV) (see chapter 8.3.1). Seed potatoes in storage can
also be covered over using Lantana camera leaves (lantana flowers).
4.6 Seed storage
4.6.1 Storage conditions
Storage conditions influence sprout quality of seed potatoes. Proper storage will
provide high quality, large, robust and uniform-length sprouts. Storage techniques
vary depending on where storage takes place. Sometimes seed potatoes are stored
in sacks, in baskets or spread out on top of each other. Using sacks or baskets can
save space, but can cause uneven sprouting as tubers on the top sprout more
quickly than those underneath. Furthermore, storing sacks or baskets on top of each
other can damage seed tubers making them more vulnerable to pests and disease.
If spread out in storage, tubers will sprouts uniformly. This requires a larger storage
area, which must always be kept dry as damp or wet floors allow diseases,
particularly tuber rot, to affect seed potatoes.
There are three storage lighting categories:
• Dark storage: when there is no light in a storage area.
o Advantages: reduces pest attack in storage and produces seeds potatoes with
more uniform sprout growth.
o Disadvantages: sprouting takes a long time - up to 3 or 4 months. Sprouts are
white in color showing that sprouting is not so good.
• Light storage: when there is full light in a place. This can be sunlight or electric
light.
o Advantages: sprouts are robust and bluish in color, which is a sign of good
sprouting. Storage time is shorter at about 2-3 months.
o Disadvantage: Lighting increases the temperature in the storage area and
causes seed tubers to sprout prematurely. Uneven lighting causes sprouts to
grow irregularly and abnormally, with small and elongated sprouts. Full electric
lighting will increase storage costs. Furthermore, pests like potato tuber moths
enjoy relatively bright places and more damage occurs in these conditions.
• Dark-light combination storage: is a storage technique used to overcome the
drawbacks of the two methods above. Seed tubers are stored in the dark for two
months, and then exposed to full light for the following month.
o Advantages: uniform and robust sprout growth, sprouting time is quicker, and
potato tuber moth damage is low.
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ALL ABOUT POTATOES