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1

Different pathways of embryo sac development in Galinsoga parviflora Cav.

100%
Pietrusiewicz J., Domaciuk M., Bednara J.
Acta Biologica Cracoviensia. Series Botanica. Supplement
|
2005
|
tom 47
|
nr 1
2

Megasporogenesis and embryo sac development in Bupleurum longifolium L. (Umbelliferae)

84%
Chojnacki W.
Zeszyty Naukowe Wydziału Biologii, Geografii i Oceanologii. Uniwersytet Gdański. Biologia
|
1984
|
nr 05
3

Embryo sac development on facultative apomixis in Woonyoungia septentrionalis (Dandy) Law

84%
Ye X.-L., Zeng Q.-W., Wang Y.-Q., Liang C.-Y.
Acta Biologica Cracoviensia. Series Botanica. Supplement
|
2005
|
tom 47
|
nr 1
4

In vitro embryo sac development via ovule cultures in Doritis pulcherrima

84%
Ye X.-L., Wu C.-H., Liang C.-Y.
Acta Biologica Cracoviensia. Series Botanica. Supplement
|
2005
|
tom 47
|
nr 1
5

Timing of megasporogenesis in Tripsacum species [Poaceae] as related to the control of pomixis and sexuality

84%
Leblanc O., Savidan Y.
Polish Botanical Studies
|
1994
|
tom 08
6

Anther and ovule development in Ungnadia speciosa Endl.[Sapindaceae]

84%
Anisimova G. M., Shamrov I. I.
Bulletin of the Polish Academy of Sciences. Biological Sciences
|
1997
|
tom 45
|
nr 2-4
7

Is the blue zinc violet [Viola guestphalica Nauenb.] a taxon of hybrid origin? Evidence from embryology

84%
Siuta A., Bozek M., Jedrzejczyk M., Rostanski A., Kuta E.
Acta Biologica Cracoviensia. Series Botanica
|
2005
|
tom 47
|
nr 1
Investigations of reproductive processes of the blue zinc violet (Viola guestphalica Nauenb.) from its natural location in Germany (Blankenrode) and from two sites of introduction in Poland (Wełnowiec zinc spoil and a private garden in Sosnowiec-Ostrowy Górnicze) showed significant disturbances resulting in reduced plant fertility. Pollen viability estimated by acetocarmine staining was relatively low, with 54% viable pollen grains in plants from Wełnowiec and 62% from the garden. Specimens from Blankenrode had 80% viable pollen but the pollen grains differed in size conspicuously. Giant abnormal pollen grains accompanied very small ones. Necrosis affected anthers and pistils, including degeneration of whole anthers and ovules, whole embryo sacs or embryo sac elements, and abortion of embryos. The pathway of female gametophyte and embryo development was normal in 61% of the ovules. Necrosis of somatic tissues and generative cells at different developmental stages was found in 28% of the ovules, and irregular development in 11% of them. As a consequence, embryo viability was reduced to 33%. Embryological data indicated that V. guestphalica is not a well-stabilized genotype. The possible origin of the blue zinc violet is discussed.
8

Nucellus typification and ovule classification

84%
Shamrov I. I.
Bulletin of the Polish Academy of Sciences. Biological Sciences
|
1997
|
tom 45
|
nr 2-4
9

Morphogenesis of seed of Dactylorhiza baltica [Orchidaceae]

84%
Zolotukhina N. O., Andronova E. V., Evdokimova E. E., Shamrov I. I.
Acta Biologica Cracoviensia. Series Botanica. Supplement
|
1999
|
tom 41
|
nr 1
10

Study of megasporogenesis and female gametophyte formation in Taraxacum belorussicum Val. N. Tikhom. (sect. Palustria) using Nomarski DIC optics

67%
Janas A., Musial K., Koscinska-Pajak M.
Acta Biologica Cracoviensia. Series Botanica. Supplement
|
2014
|
tom 56
|
nr 1
11
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Cytoembryology of infertile segregants of the hybrid Lupinus varius L. x L. digitatus Forsk

67%
Kazimierska E. M., Kazimierski T.
Journal of Applied Genetics
|
1995
|
tom 36
|
nr 3
In F₂, F₃ and F₄ generations of one hybrid line of Lupinus varius × L. digitatus, segregation into infertile and fertile plants in the ratio 3:1 was observed. Cytoembryological analyses showed that sterility was caused by irregularities in megasporocyte formation, in megasporogenesis and megagametogenesis. The following abnormalities lead to female sterility: no megasporogenic cells separated in nucelluses; in other nucelluses with megaspore mother cells, these cells underwent vacuolation and died before reduction division. In the megaspore mother cells, in which probably meiosis occurs, the megasporocyte division is irregular; a restitution nucleus is frequently formed after reduction division and such megasporocyte develops into an embryo sac. In 8-nucleate embryo sacs a change in the nucellus polarization was observed, while in rarely encountered embryo sacs the embryo cells underwent vacuolation and then died. Female sterility in the studied segregants is determined genetically, whereas sterilization of reproduction cells is a developing process throughout the period of sporocyte and female gametophyte formation.
12

Apomixis in Brachiaria decumbens Stapf.: gametophytic development and reproductive calendar

67%
Dusi D. M. A., Willemse M. T. M.
Acta Biologica Cracoviensia. Series Botanica
|
1999
|
tom 41
Brachiaria decumbens is a forage grass widely cultivated in tropical areas. This apomictic species reproduces mainly by facultative apospory. A comparison of male and female gamete development between the diploid sexual ecotype and the tetraploid apomictic B. decumbens was made. Aspects of sporophytic and gametophytic development such as developmental stage, several morphological variations, and callose deposition during meiosis are compiled in a real-time reproductive calendar which can be used to select plants as well as reproductive stages. Based on this calendar, part of the differences observed may be related to tetraploidy. Apomictic embryo sacs are formed earlier than the sexual ones, and callose deposition during meiosis follows a different pattern in sexual and apomictic plants. Effects of apomixis are expressed during both male and female development.
13

Flower size and developmental stage of Allium cepa L. umbels

67%
Klein M., Korzonek D.
Acta Biologica Cracoviensia. Series Botanica
|
1999
|
tom 41
In onion, seven stages of umbel development were distinguished with regard to the size of umbels, flower buds and developmental stages of male and female gametophytes. At the beginning of blooming, the stage at which buds are most often collected for induction of gynogenesis, flower bud length ranged from 2.0 to 5.0 mm, and the stages from archesporial cell to mature embryo sac were observed in the ovules. Microspores and bicellular pollen grains were observed in the anthers. Flower bud size was not an accurate indicator of pollen development. Buds of the same size but originating from umbels at different developmental stages were characterized by different stages of pollen development.
14

Translocation pathways for metabolites in developing ovules of Gentiana cruciata L., Gymnadenia conopsea [L.] R.Br., Gagea stipitata Merklin and Luzula pedemontana Boiss.et Reut.

67%
Shamrov I. I.
Acta Biologica Cracoviensia. Series Botanica
|
2000
|
tom 42
|
nr 1
The metabolites in the ovule come from the receptacle, ovary wall and placenta. They are accumulated in the chalaza and then translocated in reproductive and somatic structures via a system of specialized tissues. The hypostase is of great importance because it lies at the boundary of the chalaza with the nucellus and integuments, and contacts the vascular bundle. In the megagametophyte, the cell walls, which have many outgrowths, receive metabolites from the hypostase via podium and postament tissues. Histochemical data on accumulation of proteins, polysaccharides, lignin and tannins in tissues during ovule and seed development are presented. The dynamics of these substances and the character of metabolism in tissues are suggested as indicators of metabolite flow.
15
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Rapid assessment of early embryo development in some wide crosses of cereals

59%
Slusarkiewicz-Jarzina A., Ponitka A., Wojciechowska B., Wozna J.
Journal of Applied Genetics
|
2000
|
tom 41
|
nr 2
16

In vitro pollination of excised ovaries

59%
Zenkteler M.
Acta Biologica Cracoviensia. Series Botanica
|
1999
|
tom 41
In vitro placental pollination can be employed to overcome barriers of self-incompatibility and cross-incompatibility. Pollen grains of self-incompatible plants are capable of germinating directly on ovules, and the whole process of sexual reproduction can be accomplished. In some combinations of crosses, direct pollination of ovules enables prezygotic incompatibility barriers to be overcome. As a result, hybrid embryos or even hybrid plants can develop, depending on the partners crossed. Pollen grains germinate abundantly on immature ovules irrespective of the stage of megasporogenesis or megagametogenesis, and their tubes can penetrate the integuments and the nucellus cells. Preliminary investigations revealed that pollen grains of seven selected species of gymnosperms germinated on ovules of various species of Angiospermae. Embryological analysis of ovules of Melandrium album fixed 3 days after pollination with pollen of Pinus wallihiana revealed the presence of remnants of pollen tubes and 2-celled embryos in the embryo sacs. Those preliminary observations have not been described heretofore.
17

Embryological analysis of Aphanes arvensis L. [Rosaceae]

59%
Izmailow R.
Acta Biologica Cracoviensia. Series Botanica
|
1999
|
tom 41
The paper deals with the embryology of Aphanes arvensis L. and refers to plant material from Poland. Examination of various developmental stages revealed most characteristic features of sexual reproduction. Only a few ovules showed a tendency to elementary apomictic processes in the form of sporadically observed initial cells or young aposporous embryo sacs. The apomictic processes were not continued, but there is reason to believe they could be completed in some ovules. The results are discussed in a taxonomic context.
18

Ovule and seed development in Vaccinium myrtillus L. [Ericaceae]

59%
Anisimova G. M., Shamrov I. I.
Acta Biologica Cracoviensia. Series Botanica
|
2000
|
tom 42
|
nr 1
Ovule and seed morphogenesis in Vaccinium myrtillus was studied here for the first time. The gynaeceum is paracarpous. The ovules are developed at sutural-angular placentae. Periclinal divisions of the subepidermal cells of the placenta usually precede formation of the ovular primordia. The ovules are ana-campylotropous, medionucellate, unitegmic, leptochalazal and sessile. The initials and dynamics of different ovule structures were determined. The chalazal zone of the nucellus transforms into the postamento-podium. The integument is of dermal origin, with a typical endothelium. The ovule has a hypostase, which is initiated with the beginning of ovular primordium differentiation. It is cup-shaped in the mature ovule and consists of 2-3 layers. Their cell walls are not lignified. The nucellus, integumental parenchyma, endothelium and hypostase do not persist in the mature seed. The latter is exotestal. The embryo sac develops according to the Polygonum type. The endosperm is cellular, with micropylar and chalazal haustoria. The mature embryo is large and well differentiated into organs.
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