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A four-year study examined the degree of self-pollination and self-fertility in the following cultivars of Ribes nigrum L.: Ben Alder, Ben Lomond, Ben Nevis, Ben Tirran, Ceres, Ojebyn, Titania and Triton. The percentage of flowers setting fruit largely depended on the cultivar and on the pollination treatment. The most fruits (over 60%) were obtained in free-pollination conditions; 44-64% fruit set...
This study investigated cross-reactivity between allergens of Cupressaceae and Fagaceae pollen. Human IgE raised against Cupressus arizonica pollen allergen was used to demonstrate the presence of related allergens on ultrathin sections of Fagaceae pollen (Quercus ilex, Castanea sativa, Fagus sylvatica). Tissue localization of the cross-reactive allergen was investigated by immunogold electron microscopy...
Variation in the level of self-incompatibility (SI) was quantified in 14 Polish lines of cabbage (Brassica oleracea L. var. capitata) pollinated in various temperature/humidity conditions. Two methods were used to measure the expression of incompatibility: counts of seed set and counts of pollen tubes penetrating the styles 48 h after self-pollination. The level of self-incompatibility varied distinctly...
Reproduction of Echium vulgare L. was examined in situ at two contaminated sites (Silesia, Poland): a zinc spoil heap in Katowice-Wełnowiec, and the surroundings of the Żelazny Most copper post-flotation waste reservoir. Plants from uncontaminated sites (near Rymanów) were studied as the control material. We compared the reproductive capacity of plants in the stress conditions to that of plants from...
This work is the first characterization at cellular and subcellular level of the main cellular events occurring in the first stages of microspore embryogenesis. Microspore embryogenesis was induced in two varieties of Citrus Clementina (Nules and Monreal). The results showed that one of the most responsive stages for embryogenesis was the vacuolate microspore. Microscopic analysis revealed specific...
The paper reports a comparative study of storage protein synthesis and enzyme activity during zygotic and somatic embryogenesis of silver fir. The SDS-PAGE profiles of storage proteins in zygotic and somatic embryos were similar but not identical. Six storage protein fractions were detected in zygotic embryos, as compared with eleven fractions in somatic embryos. The principal storage protein of zygotic...
The theory of critical periods in plant ontogenesis has been elaborated from studies of integral morphogenetic processes on different levels. The periodization of the development of various reproductive structures (anther, microspore, pollen grain, ovule, megagametophyte, egg cell, zygote and embryo) has been worked out from data on morphogenesis using systemic and complex morphophysiological approaches...
In order to study microtubule organization during pollen germination and pollen tube growth in Olea europaea, we applied immunofluorescence microscopy using mouse monoclonal antibody against α-tubulin as primary antibody and FITC-conjugated goat antimouse IgG as secondary antibody. DAPI enabled observation of the vegetative nucleus entering the emerging pollen tube before the generative cell. The...
This paper describes the distribution of Ole e 3 allergen and its transcripts in the developing anther and in mature olive pollen. Northern blot and RT-PCR analyses over the course of pollen development show that Ole e 3 transcripts accumulate exclusively in mature pollen. This gene therefore corresponds to a "late gene." The sequences amplified by RT-PCR display high identity with those...
This study uses cytochemical tests, electron spectroscopic imaging and electron energy loss spectroscopy techniques to identify and localize the reserves inside the generative cell of Hermodactylus tuberosus pollen. Cytochemical probes applied to sections observed by light and transmission electron microscopy indicated that the generative cell contains large osmiophilic bodies probably made of phytic...
Screening of male gametophytie mutants from the Versailles collection of T-DNA transformants allowed us to isolate and characterize two novel genes: KINKY POLLEN (KIP) and POKY POLLEN TUBE (POK), which are required for correct tip growth in Arabidopsis thaliana. As KIP and POK are expressed in all plant tissues, though to a higher level in pollen and roots, their roles may not be restricted to tip...
Sexual reproduction in angiosperms is an interactive process involving the sporophyte, gametophytes, embryo and endosperm as well as the environment, aimed at achieving pollination, fertilization and dispersal. This interaction occurs via an interface with nutrients and signals outside the cell and even outside the plant. Sexual reproduction has a history. In water, algae have different types of sex...
Pollen of Lagerstroemia indica was collected from polluted (SO2, NOx, CO, HC, airborne particulate matter) and less polluted areas of Tehran city, Iran. Some pollen from less polluted areas was exposed to polluted air for 10 and 20 days. To determine the effect of air pollution on proteins, pollen extracts were analyzed by the Bradford method and SDS-PAGE. Study of pollen structure by light and scanning...
To study mitochondria and plastid involvement in plant development, particularly in sexual reproduction, we made use of the Arabidospis thaliana T-DNA insertion collection developed in Versailles. Mutants affected in the nuclear genes that encode proteins predicted to be targeted to organelles were identified using two complementary strategies. In the first (forward genetics), mutants chosen for their...
Embryogenesis is a critical stage of the sporophytic life cycle, during which the basic body plan of the plant is established. Although zygotic embryogenesis is induced by fusion of the sperm and egg nuclei, plant cells can initiate embryo development without fertilization. For example, cultured somatic and male gametic cells can be induced to undergo somatic and microspore embryogenesis, respectively...
A comparative morphogenetic study of reproductive organs of chrysanthemums is conducted using morphological analysis. Morphological changes during the development of a generative shoot and organogenesis from first through ninth phases were described. The flat apex becomes spherical in form. An inflorescence apical meristem initiates involucral bract. An initiation of floret primordia is followed an...
A study of Gentiana cruciata L. (Gentianaceae), Gymnadenia conopsea (L.) R.Br. (Orchidaceae) and Luzula pedemontana Boiss. et Reut. (Juncaceae) showed differences in the number and characteristics of critical stages in ovule and seed development. The shared critical stages explain the general direction of the formation of reproductive structures and surrounding tissues. The taxon-specific critical...
The actin cytoskeleton of endosperm and of the mature endosperm chalazal haustorium cell of Rhinanthus serotinus was examined by immunohistochemistry and epifluorescence microscopy. A prominent actin cytoskeleton composed of numerous cross-linked filaments is present at the distal pole of the chalazal haustorium cell. Thick, longitudinally oriented bundles of microfilaments localize in transvacuolar...
The study found that the monocot Agapanthus praecox from different cultivation localities has a stable tendency to develop dicotyledonous together with monocotyledonous and transitional forms, with various degrees of cotyledonary fusion. The morphogenetic events during embryogenesis leading to this diversity are presented and analyzed.
Conserved 14-3-3 proteins have been shown to play regulatory roles in eukaryotic cells, including cell cycle control and differentiation. We were interested in the possible involvement of 14-3-3 proteins in the embryogenic process of barley (Hordeum vulgare L.). Barley microspore-derived embryo development was used as a model system. Immunolocalization of three barley 14-3-3 isoforms, 14-3-3A, 14-3-3B...
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