Introduction
Moisture content of seeds is one of the most important factors in the maintenance of seed quality. From the time of harvest to time of planting, seed moisture varies and if it rises above certain critical levels for any appreciable time period at any stage there is danger of undesirable stimulation of physiological processes within the seed with consequent weakening and loss of seed viability. The moisture content a seed sample is the loss in weight when it is dried. It is expressed as a percentage of the weight of the original sample.
Moisture and Seed Health
At all times the substratum must contain sufficient moisture to meet the requirements for germination, but the moisture must not be excessive. Except where a high moisture level is recommended, the substratum should not be so wet that a film of water forms around the seed. Where a low moisture level is recommended, the moist substratum should be pressed against a dry absorbent surface, such as a dry paper towel, or blotter, to remove excess water.
In order to reduce the need for the addition of water after planting, the relative humidity of the air surrounding the seeds should be kept as close as possible to saturation to prevent loss by evaporation. A high relative humidity around the seeds can be provided by keeping water in the germination chamber or cabinet, by enclosing tests on paper in dishes, or by covering sand or soil tests with moist blotters, or glass plates, until the seedlings emerge. Circulation of air may be necessary to prevent excessive condensation of moisture on the seedlings.
For measuring moisture content Reference methods, Routine methods, and Practical methods are used.
Ag.
Technologies
(Seeds)
