For analysis of metaphase chromosomes, any tissue containing dividing cells can be used: Root tips from young seedlings, from newly grown roots at the edge of plant pots or hydroponic culture are all suitable. Alternatively, flower buds, anthers, carpels or leaf or apical meristems can be used. Includes metaphase arresting reagents. - [Read Accumulation and Fixation of Plant Metaphase Chromosomes Protocol]
In most natural habitats, Arabidopsis is a winter annual: Its seeds germinate in the fall, the young plants survive the winter, floral meristems emerge in the spring, and only the seeds survive the summer months. Most common laboratory varieties of Arabidopsis flower within 4 weeks of germination, and seeds can be collected after an additional 4-6 weeks. - [Read Cultivation of Arabidopsis Protocol]
Protocol describes a useful way to observe the development of embryos, as well as meristems & young primordia developing at the shoot apex by confocal microscopy after staining the nuclei with propidium iodide. The number of cells can be exactly quantified in a meristem or in young primordia. Because embryonic & meristematic cells are largely filled out by their nuclei, it is easier to image only the nuclei. This method allows analysis of whole-mount material, which is more easily reconstructed. - [Read Protocol for Nuclear Staining of Plants for Confocal Microscopy]