原版拟南芥规范种植手册

a cold treatment to break dormancy of seeds, also called stratification, is very

important for plantings utilizing freshly harvested seeds, which have more

pronounced dormancy. Most widely used lines have moderate dormancy, and cold treatment may not be required when planting older seeds of these lines. For

certain lines, as many as 7 days of cold treatment is necessary. Cold treatment of dry seeds is normally not effective in breaking dormancy.

8. After cold treatment, place pots in growth area (growth chamber, growth room, greenhouse, etc) and maintain approx 2 cm of water around base of pots during the germination phase. Leave plastic wrap on for plants grown in growth

chamber.

Growth conditions

In general, the growth and development of Arabidopsis plants, including time to flowering and time to harvest depend on several growth conditions in addition to the genetic background. Management of water, nutrition, light and temperature will ensure that healthy plants develop and produce high quality and quantity of seeds. Under continuous light, 25°C, good water supply and good nutrition, seeds of the commonly used lines germinate within 3-5 days, bolt and flower around 3-4 weeks, and can be harvested within 8-12 weeks.

Water and nutrition

Maintenance of soil moisture is imperative for successful germination of seeds. This can be ensured in one of two ways: a) leaving the plastic with small

perforations over the pots or tubs, or b) placing the pots in flats without the plastic cover and maintaining a depth of 1-3 cm of water, which is maintained

continually until all plants germinate and have expanded cotyledons. We prefer the former for growth chamber and the latter for the greenhouse. The first method is dangerous in the greenhouse setting, due to the potential for overheating

underneath the plastic covering on sunny days, killing the germinating seedlings.

After germination, plants are watered as needed to avoid water stress. Water is best applied by sub-irrigation when the soil begins to dry. Sub-irrigation can be achieved by placing pots into flats or trays, allowing proper drainage of the soil. Over-watering should be avoided due to the potential for algal or fungal growth on the soil surface. Over-watering of greenhouse plants also provides favorable soil conditions for fungus gnat larvae. More frequent watering may be necessary during the first few days, as it is necessary to avoid any drying before the first two true leaves begin expanding. After plants have developed true leaves, watering frequency may be reduced to as low as once or twice per week until the plants flower. The water requirement of plants increases dramatically during silique

filling. Daily watering at this stage is necessary for good seed production.