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