Flow cytometry for plant breeding

Flow cytometry is a well known and established technique for ploidy analysis in plant breeding. It is routinely used to characterize parent plants, to screen offspring after interploidy crosses, to control ploidy levels during seed multiplication or to evaluate polyploidisation experiments. Recent developments in the apparatus itself, as well as in automated sample preparation, simplified the technique and made it more cost effective. Commonly flow cytometry analyses the relative DNA content in the cell related to the ploidy level of the plant. Notwithstanding the DNA content is correlated to chromosome amounts, no information is obtained on exact chromosome numbers. Besides ploidy, information on genome sizes can be obtained. For example in interspecific hybridisation genome sizes can be used to evaluate the hybrid nature of seedlings. Also other applications are useful for breeders. As an example the analysis of (unreduced) pollen is discussed.