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Abstract

This study is the first comparison of the morphology of pollen grains in ten cultivars of three species of the Taxus,

Torreya nucifera and Cephalotaxus harringtonia var. drupacea genera. The material came from the Botanical

Garden of Adam Mickiewicz University in Poznań, Poland. Each measurement sample consisted of 50 pollen

grains. In total, 750 pollen grains were analyzed. Light and electron scanning microscopy was used for the morphometric

observation and analysis of pollen grains. The pollen grains were inaperturate and classified as small

and medium-sized. They were prolate-spheroidal, subprolate to prolate in shape. The surface of the exine was

microverrucate-orbiculate, perforate in Cephalotaxus harringtonia var. drupacea, granulate-orbiculate, perforate

in all Taxus taxa and granulate-microverrucate-orbiculate, perforate in Torreya. The orbicules were rounded to

oval in surface view, and the size was considerably diversified. The pollen features were insufficient to distinguish

between individual Taxus members – only groups were identified. The values of the coefficient of variability of

three features (LA, SA and LA/SA) were significantly lower than the orbicule diameter. The pollen surface of all

Taxus specimens was similar, so it was not a good identification criterion. The pollen grains of the Taxus taxa

were smaller and had more orbicules than Cephalotaxus and Torreya. Palynological studies provided taxonomic

support for recognition of two different genera of the Cephalotaxaceae and Taxaceae families, which are closely

related.

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Authors and Affiliations

Joanna Bykowska
Małgorzata Klimko
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Abstract

Chromosome numbers for 15 taxa of Hieracium L. s.str. from Bulgaria, Greece, Macedonia, Poland, Romania

and Slovakia are given and their metaphase plates are illustrated. Chromosome numbers are published for the

first time for H. vagneri Pax s.str. (2n = 4x = 36), H. wiesbaurianum subsp. herculanum Zahn (2n = 4x = 36),

H. wiesbaurianum subsp. kelainephes Nyár. & Zahn (2n = 3x = 27), as well as for two undescribed species

of hybrid origin between H. umbellatum L. and H. wiesbaurianum s.lat. (2n = 3x = 27), and between H. sparsum

Friv. and H. schmidtii s.lat. (2n = 3x = 27), and for three undescribed species of the H. djimilense agg.

(2n = 3x = 27), H. heldreichii agg. (2n = 3x = 27), and H. sparsum agg. (2n = 3x = 27). Furthermore, the chromosome

numbers of two undescribed species of hybrid origin between H. umbellatum L. and H. wiesbaurianum

s.lat. (2n = 3x = 27), and between H. sparsum Friv. and H. schmidtii s.lat. (2n = 3x = 27) are given. A new,

tetraploid chromosome number is given for H. barbatum Tausch from the northernmost locality of the species

in Europe.

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Authors and Affiliations

Krystyna Musiał
Agnieszka Janas
Zbigniew Szeląg
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Abstract

An efficient system of micropropagation via somatic embryogenesis from root-derived callus was established in

Arabica coffee (Coffea arabica L.). Twenty-six callus lines were induced on MS (Murashige and Skoog, 1962)

medium supplemented with combinations of NAA (0, 0.1, 0.5, 1 and 2 mg/L) plus BA (0, 1 and 2 mg/L), or 2,4-D

(0, 0.1, 0.5, 1 and 2 mg/L) plus TDZ (0, 1 and 2 mg/L). Subsequently, two types of somatic embryos were obtained

from callus cultures and named S-type and I-type embryos. The S-type embryos were obtained from an 18-monthold

callus line which was induced and maintained at 2 mg/L TDZ and 0.1 mg/L 2,4-D near the end of each period

of the subculture. These embryos have a developmental barrier, which did not pass through the torpedo stage

and could be overcome by a supplement of 2 or 5 mg/L BA. The I-type embryos were induced from 3-month-old

callus when transferred onto induction media, i.e., MS supplemented with TDZ (2 and 5 mg/L) plus 2,4-D (0 and

0.1 mg/L). The significantly highest response, i.e., 13.3 embryos per callus clump was obtained at 2 mg/L TDZ.

In this study, the results reveal that TDZ has a crucial effect on embryogenic callus induction, proliferation and

subsequent somatic embryogenesis.

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Authors and Affiliations

Yi-Chieh Wang
Meng-Ze Lin
Bin Huang
Hsiao-Hang Chung
Jen-Tsung Chen
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Abstract

To keep genetic diversity, flowering plants have developed a self-incompatibility system, which can prevent self-pollination.

It has been reported that calcium concentration in pistil papilla cells was increased after self-pollination

in transformed self-incompatible Arabidopsis thaliana. In this study, we found that CML27 changed its expression

level for both mRNA and protein when compared to transcriptome and proteome. At the same time, CML27 was

expressed in the anther and pistil at a high level and reached up to 5-fold up-regulated expression in the pistil

at 1 h post-pollination when compared to 0 min. In order to find out potential proteins that may interact with

BoCML27, BoCML27 was expressed in and isolated from E. coli. After its co-incubation with Brassica oleracea

pistil proteins, the products were separated on SDS-PAGE gels. We found a specific band at the position between

130–180 kDa. Through LC-MS-MS (Q-TOF) analysis, eight proteins were identified from the band. The proteins

include 26S proteasome non-ATPase regulatory (26S), Phospholipase D, alpha 2 (PLDα2) involved in Ca2+ binding

and Coatomer subunit alpha-2-like (Coatomer) involved in vesicle mediated transport. All of these identified

proteins provide new insights for the self-incompatibility response in B. oleracea, specific for increasing Ca2+

concentration in pistil papilla cells.

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Authors and Affiliations

Xiao Ping Lian
Jing Zeng
He Cui Zhang
Xiao Hong Yang
Liang Zhao
Li Quan Zhu
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Abstract

Plant tissue culture techniques have become an integral part of progress in plant science research due to the opportunity offered for close study of detailed plant development with applications in food production through crop improvement, secondary metabolites production and conservation of species. Because the techniques involve growing plants under controlled conditions different from their natural outdoor environment, the plants need adjustments in physiology, anatomy and metabolism for successful in vitro propagation. Therefore, the protocol has to be optimized for a given species or genotype due to the variability in physiological and growth requirement. Developing the protocol is hampered by several physiological and developmental aberrations in the anatomy and physiology of the plantlets, attributed to in vitro culture conditions of high humidity, low light levels and hetero- or mixotrophic conditions. Some of the culture-induced anomalies become genetic, and the phenotype is inherited by clonal progenies while others are temporary and can be corrected at a later stage of protocol development through changes in anatomy, physiology and metabolism. The success of protocols relies on the transfer of plantlets to field conditions which has been achieved with many species through stages of acclimatization, while with others it remains a challenging task. This review discusses various adjustments in nutrition, physiology and anatomy of micro-propagated plants and field grown ones, as well as anomalies induced by the in vitro culture conditions.

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Authors and Affiliations

Beata Myśków
Ilona Czyczyło-Mysza
Sandra Sokołowska
Stefan Stojałowski
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Abstract

Petiole bending in detached leaves of Bryophyllum calycinum was intensively investigated in relation to polar auxin transport in petioles. When detached leaves were placed leaf blade face down, clear petiole bending was observed. On the other hand, no petiole bending was found when detached leaves were placed leaf blade face up. Indole-3-acetic acid (IAA) exogenously applied to petioles was significantly effective to induce and/or stimulate petiole bending when detached leaves were placed leaf blade face down. To clarify the mechanisms of petiole bending in detached leaves of B. calycinum when they were placed leaf blade face down, the effects of application of IAA, ethephon which is an ethylene releasing compound, inhibitors of polar auxin transport such as 2,3,5-tiiodobenzoic acid (TIBA), N-1-naphthylphthalamic acid (NPA) and 9-hydroxyfluorene-9-carboxylic acid (HFCA) and methyl jasmonate (JA-Me) were thoroughly investigated. Ethephon was not effective to enhance petiole bending, suggesting that ethylene derived from exogenously applied IAA does not play an important role in petiole bending in detachd leaves of B. calycinum. This suggestion was strongly supported by the fact that ethephon exogenously applied to petioles in intact plant of B. calycinum had no effect on inducing epinasty and/or hyponasty either (Ueda et al., 2018). Potent inhibitors of polar auxin transport, TIBA and HFCA, and JA-Me were extremely effective to inhibit petiole bending but NPA was not. Almost no petiole bending was observed in excised petiole segments without the leaf blade. Applicaton of IAA to the cut surface of petioles in the leaf blade side strongly promoted petiole bending. Polar auxin transport in excised petioles of B. calycinum was intensively investigated using radiolabeled IAA ([1-14C] IAA). Clear polar auxin transport was observed in excised petiole segments, indicating that auxin allows movement in one direction: from the leaf blade side to the stem side in petioles. When detached leaves were placed only leaf blade face down, transported 14C-IAA was reduced in the lower side of the excised petioles. These results strongly suggest that transport and/or lateral movement of endogenous auxin biosynthesized or produced in the leaf blade are necessary to induce petiole bending in detached leaves of B. calycinum. Mechanisms of petiole bending in detached leaves of B. calycinum are also discussed in relation to polar auxin transport and lateral movement of auxin.

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Authors and Affiliations

Junichi Ueda
Kensuke Miyamoto
Justyna Góraj-Koniarska
Marian Saniewski
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Abstract

We have developed an effective protocol for in vitro micropropagation in order to obtain large numbers of identical plants and another protocol for in vitro polyploidization of Ajuga reptans, based on the use of oryzalin. Two donor plants of A. reptans (AR 4, AR 7) were treated with 0, 1, 5, 10 μM oryzalin for 2 weeks. The analysis of the ploidy level of these plants was verified by flow cytometric analysis using the internal standardization method. The effects of polyploidization on growth as well as morphological and stomatal size were also measured. After in vitro polyploidization, some plants became tetraploids or octoploids. The most efficient conditions for inducing tetraploidy were the treatments with 10 μM oryzalin.

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Authors and Affiliations

Michaela Švécarová
Božena Navrátilová
Vladan Ondřej

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