in order to identify the best maturity time for excision of fertilized ovules in interspecific hybridization, intercrosses were made between two diploid (gossypium herbaceum and g. arboreum, 2n=26) and two tetraploid species (g. barbadense and g. hirsutum, 2n=52). flower morphology, growth rate of ovules and ovaries, as well as fiber growth pattern in various time scales post anthesis were reco...

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BACKGROUND AND AIMS Lady's slipper orchids (Paphiopedilum) are of high value in floriculture, and interspecific hybridization has long been used for breeding improved cultivars; however, information regarding the genome affinities of species and chromosome pairing behaviour of the hybrids remains almost unknown. The present work analyses the meiotic behaviour of interspecific hybrids by genomic...