拟南芥种植手册_tair(10)

原版拟南芥规范种植手册

glass jars (do not use plastic due to static effects), or in small manila "coin" envelopes to allow seeds to dry.

The moisture content of Arabidopsis seeds after threshing is usually around 10%. The seeds should be dried to 5-6% moisture, prior to storage. This is verified by moisture testing, as outlined in the protocol below, on samples that can be disposed. Higher moisture content can cause seed deterioration. There are many methods available for drying seeds. The safest method is to air-dry the seeds at room temperature for 1-3 weeks. Low relative humidity (20-30%) is necessary for seeds to reach the desired

moisture content. The lower the humidity, the faster the seeds will dry and the lower their final moisture content. If after testing, the moisture content is not low enough, continue to dry further and check again.

General Considerations

Moisture testing is necessary to verify that seeds are dry enough for storage. Seed moisture content can be determined by several methods. The method outlined is a destructive method, and the seeds employed for testing will no longer be viable.

1. The total weight of seeds used for a moisture content determination should be

sufficient to make the test accurate and yet not be wasteful of seeds. The sample should be fully representative of the accession and a minimum of 100 mg should be used to prepare the samples for the test. Accurate results were obtained using approximately 200 mg of seeds.

2. The lower the weight of seed used, the more accuracy is required to achieve a true result. Small samples should be weighed with an analytical balance to four decimal

places using light-weight dishes (small aluminum dishes or petri dishes), so that the ratio of the weight of the seeds and the dish is not too disproportionate.

3. It is suggested that a minimum of three replicates of 100 mg of seeds or two replicates of 200 mg of seeds per sample be used for the moisture content determination.

4. Always work with care and finish one sample at a time. Do not leave the dishes open in the laboratory between weighings because the seeds will either lose or absorb water from the air and small changes in weights can result in large differences in the calculations when the amount of seed used is small.

5. High temperatures cannot be used to determine the moisture content because the oil will also vaporize and give a false result of water plus oil content. Temperatures of just over 100°C allow evaporation of water and minimal vaporization of oils.