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A study on the different features of male flowers in the dioecious plant Asparagus officinalis
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Monoclonal antibodies to antigens of anthers from a dioeciuos plant: Asparagus officinalis L.
No full textMonoclonal antibodies were raised by immunizing mice with a crude extract from anthers of mature male flowers of the dioecious plant Asparagus officinalis L. To isolate anther specific antibodies, hybridoma culture supernatants were screened by enzyme-linked immunosorbent assay (ELISA) against extracts from anthers, leaves, roots of male Asparagus plants. We were able to isolate a set of anther specific monoclonal antibodies recognizing four different epitopes, as shown by ELISA experiments, Western blotting and immunolocalization. Only one of the antibodies is periodate-sensitive, implying that the epitope it recognizes is carbohydrate in nature. Indirect immunofluorescence observations and timing experiments seem to suggest that at least three of the antigens are localized in pollen cells and are present in large amounts only at relatively late times during anther development
Different kinds of male flowers in the dioecious plant Asparagus of officinalis L.
No full textIn the dioecious plant Asparagus officinalis L. the female plants bear flowers that are all strictly of the same type, with well-developed pistils and collapsed and consistently sterile rudiments of anthers, while male plants, on the contrary, show a great variety of vestigial female organs, from small, rudimentary ovaries with no style and stigma, up to pistils provided with a rather long style that is often enlarged in a stigma. In our investigations, we used homozygous male and female doubled haploid plants obtained from in vitro anther culture, the all-male F1 progeny and male individuals from subsequent backcrosses. The results showed that: (1) the character length of the style is genetically inherited and involves at least two genes, the influence of the environment being quite negligible; (2) in male pistils provided with style and stigmatic papillae, the pollination and growth of the pollen tubes up to the ovules do actually occur as a rule, the only barrier to fertilization being the absence of normal embryo sacs inside the ovules; (3) the character length of the style is a very reliable marker of the trend towards hermaphroditism in Asparagus, since a correlation always exist between length of the style, size of the ovary, tendency to self-pollination, vascularization and rate of development of the ovules inside the male ovaries. On the whole, most of our observations, together with the high inbreeding depression observed when occasional andromonoecious plants are selfed, are consistent with the hypothesis of the origin of dioecy in Asparagus from hermaphroditism via the gynodioecy pathway
Searching for sex-and flower-specific genes in some dioecious plants (Angiosperms and Gymnosperms)
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Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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