Cytogenetic Analysis of Arabidopsis

The cytogenetrcal analysis of a species enables the correlation of the structure, number and morphology of its chromosomes with heredity and variation. Most accessions of Arabidopszs thaliana L. have a diploid (2n) chromosome number of 10 (Fig. 1 ). The small genome size, convenient for many aspects of molecular genettcs, makes the chromosomes average only 1.5 pm in length (1 ,2 ) and intractable to analysts using many of the cytogenettc methods applied to other genera. However, despite the small size of chromosomes, the rapid advances in chromosome preparation methods, fluorescent microscopy, and staining since 1990 mean that analysis IS now straightforward (see refs .3 –5 ).