Question

An orthodox seed is one which can
A) Tolerate dehydration and low temperature.
B) Tolerate low temperature but not dehydration.
C) Tolerate dehydration but not low temperature.
D) None of the above.

Answer 1

Hint: Orthodox seeds can survive for many years that is, it can be preserved by removing moisture and subjecting it to low temperature. It can also help in the conservation of a certain variety of plants.

Complete answer: Orthodox seeds are seeds that have survived extreme dehydration and low temperatures. It is a part of the ex-situ conservation. Not all seeds can be preserved as orthodox seeds and not every seed can withstand drying conditions and storage conditions. The low temperature can go up to $ - 100^\circ $C. The crop seeds that are easily grown are made into orthodox seeds. The orthodox seeds are preserved seeds and can also be retrieved to form the normal seed for germination. The plant seeds or perennial seeds cannot be preserved in the orthodox form. The preservation span can be in between a year to hundreds of years. It also depends upon the moisture content inside and also storage conditions. A great example of orthodox seeds is Judean date palm seed which was 2000 years old and was successfully sprouted in 2005.
Hence, the correct answer is option A.

Note: The other type of seeds are recalcitrant seeds, which are short-lived and cannot be dried. It is also known as desiccation sensitive seeds but still, it can be dried up to 30 percent of moisture. They are stored in the growing phase and they are at high risk of microbial contamination.