Recent Cytogenetic Studies in The Genus Nicotiana

摘要: Publisher Summary This chapter discusses the cytogenetic studies on Nicotiana. The genus Nicotiana has been a favored material for inheritance and evolution in higher plants since days of pre-Mendelian hybridizers. origins species are presented these relationships summarized diagrammatically form three phylogenetic arcs. evidence shows that interspecific hybridization, with subsequent amphiploidy as well genetic recombination, played an important role . More than 300 hybrids have reported Limits consequences multiple allopolyploidy explored aneuploidy assessed. use introgressive hybridization to transfer resistance various diseases into commercial tobacco from wild is part breeding efforts. Certain exhibit striking somatic instability forming spontaneous tumors. In certain combinations, hereditary component cytoplasm found. affects either pollen sterility or plastid-controlled chlorophyll variegation. Biometrical analyses quantitative character N tabacum crosses shown preponderant additive gene effects consequent effective response selection.