Types of seed: based on long storage

There are tree types of seed based on how long they can be saved. The first type called recalcitrant, the second type is orthodox and third type is semi orthodox.

Recalcitrant seed is the seed which can not be saved for long time. Usually seed that classified in this type will be planted directly as soon as possible. Because when we delay to plant, the viability of this seed will decrease soon. How long we can keep the viability of recalcitrant is depend on how we saved the seed. Usually we can put the seed in average room temperature, about 22-27 c.d., with open container, but should be kept from sun light and rain water directly. Put the seed under balcony of the building is suggested. This saving treatment can keep the viability of seed from 1-2 week. But plant the seed directly after harvested is the better way to get high level viability.

Orthodox seed is the seed which can be saved for long time. During saving period, seed still had high level viability. The saving treatment that can be done for orthodox type is by reduce the water content of seed. Commonly, orthodox seed have water content around 12-15 %. And for the saving period, the water content is reduced to 4-6 %. One of ways to reduce the water content is by drying the seed by sun light directly. Another way is by using the mechanical engine, called seed dryer. After the water content of seed reach 4-6 %, the seed can be saved for 1-10 years. The seed should be saved with impermeable package and low temperature, around 0-5 c.d.

The last type is semi-orthodox. This type is quiet same as recalcitrant type, but the viability of seed can be saved for 1-3 months. The treatment for this type is also same as the treatment for recalcitrant seed.

Commonly, recalcitrant seed be marked by high level of water content of seed when harvested, around 70-80 %, and ripe in winter season. Orthodox type has low water of content, around 15-20%, and ripe in summer season. While semi-orthodox has 20-40% water of content when harvested.

As the conclusion , each type has special treatment. Good treatment in saving process will affect to how long the viability of seed can be kept.