studies of postmeiotic chromosomes have been impeded by the thick exine of immature pollen grains. chromosome staining of immature and adult pollen grains through conven-tional acetocarmine procedure is tedious and often leads to unsatisfactory results. an acetocarmine stain, used in conjugation with carnoy’s solution as fixative for 72 hrs or until the chlorophyll-containing tissues of spike b...

Studies of postmeiotic chromosomes have been impeded by the thick exine of immature pollen grains. Chromosome staining of immature and adult pollen grains through conventional acetocarmine procedure is tedious and often leads to unsatisfactory results. An acetocarmine stain, used in conjugation with Carnoy’s solution as fixative for 72 hrs or until the chlorophyll-containing tissues of spike be...

Plants display a remarkable capacity for cellular totipotency. An intriguing and useful example is that immature pollen cultured in vitro can pass through embryogenic development to form haploid or doubled haploid plants. However, a lack of understanding the initial mechanisms of pollen embryogenesis hampers the improvement and more effective and widespread employment of haploid technology in p...

Injection of 0-5 % colchicine into immature tillers of genotypes of Triticum aestivum, T. aestivum x Aegilops mutica and T. aestivum x Secale cereale hybrids induces asynapsis at first meiotic metaphase irrespective of the homologous or homoeologous nature of the potential pairing chromosomes. The induction of asynapsis occurs at a time during and immediately following the last premeiotic mitos...

Hop latent viroid (HLVd) is not transmissible through hop generative tissues and seeds. Here we describe the process of HLVd elimination during development of hop pollen. HLVd propagates in uninucleate hop pollen, but is eliminated at stages following first pollen mitosis during pollen vacuolization and maturation. Only traces of HLVd were detected by RT-PCR in mature pollen after anthesis and ...

weed pollen grains belonging to  the  asteraceae  family contain  a variety of  allergens inducing type i  and iv allergies in susceptible people. the  aim of this research was to compare  the  allergenic properties  of  immature  and  mature  shasta  daisy pollen  grains (chrysanthemum maximum ramond) to define the potential role of the maturation process on the allergenicity of asteraceae pol...

During pollen development each product of meiosis undergoes a stereotypical pattern of cell divisions to give rise to a three-celled gametophyte, the pollen grain. First an asymmetric mitosis generates a larger vegetative cell and a smaller generative cell, then the generative cell undergoes a second mitosis to give rise to two sperm cells. It is unknown how this pattern of cell divisions is co...

the study aimed to investigate the microsporogenesis, tapetum and pollen development in petunia hybrida juss.under control and air pollution condition. the connective shows a well-developed placentoid, giving thesporogenous tissue a crescent-shape. the sporogenous tissue of each of the four anther locules is surrounded bydimorphic tapetum. the outer (towards the epidermis) and inner (towards th...

BACKGROUND AND AIMS Cassava (Manihot esculenta), a major food staple in the tropics and subtropics, thrives even in environments undergoing threatening climate change. To satisfy the increasing demand for crop improvement and overcome the limitations of conventional breeding, the introduction of inbreeding techniques such as the production of doubled haploid lines via androgenesis or gynogenesi...