Preface

The Flow cytometry technique has is currently been employed in various fields of research. The technique is also used in modern biosystematics, speciation, evolutionary studies and in molecular breeding. Various factors influence the quality of, active nuclei isolation, which determines the success of accurate DNA estimation. The importance of extraction buffer, reference standards, fluorochrome dyes, and the process of gating is highlighted in order to understand the various steps of flow cytometry in measuring DNA. An array of compounds act as inhibitors, disrupts fluorochrome binding to DNA, and cause errors in estimating nuclear DNA content; all the above important factors are described in one chapter. Micropropagation using shoot tips and nodal stems produces true-to type plants, while callus regenerated plants show somaclonal variations - a process showing altered DNA. The role of flow cytometry in investigating the genetic homogeneity of tissue cultured populations are is reviewed in different chapters. The intra-specific and inter-specific genome and chromosome number variation with reference to gene duplication and DNA sequence loss have been described. To establish the genetic homogeneity / fidelity of regenerated plants, several DNA marker based techniques have been used. Start codon targeted polymorphism (SCoT) has emerged as one of the recently used DNA fingerprinting techniques to assess the genetic stability of tissue cultured plants and for revealingreveal cultivar differentiation and genetic diversity between wild and domesticated plants. A few chapters described the importance, applications and limitations of various molecular markers in studying genetic homogeneity, somaclonal variants and polyploidy in different groups of plants.

Much of the information is available on the website; the need to accumulate cutting-edge knowledge and flow cytometry techniques in structured book format is still essential. I sincerely hope that this updated literature of the above research will be very useful resource material to a wide range of people, especially to researchers, graduate students, teachers and other professionals in various disciplines like Botany, Biotechnology, Agriculture, Horticulture, Pharmacology and other research fields.

I am grateful to all the authors for their valuable contributions. I am indebted to publishers for agreeing to publish this effort. Last but not least, I am thankful to current Ph. D students for their help and support.