scholarly journals The effect of oleander glycosides on the germination of pollen grains and the mitosis of the generative nucleus in Tradescantia bracteata Small and Allium cepa L.

2015 ◽  
Vol 44 (3) ◽  
pp. 451-460 ◽  
Author(s):  
J. A. Tarkowska
Keyword(s):  
Allium Cepa ◽  
Water Solution ◽  
Pollen Grains ◽  
Pollen Tubes ◽  
Nerium Oleander ◽  
Generative Nucleus ◽  
Effect Of Water ◽  
Allium Cepa L ◽  
Germination Of Pollen

The effect of water solution of a mixture of glycosides from oleander (<i>Nerium oleander</i> L.) on the germination of pollen grains and on the mitosis of the generative nucleus in <i>Tradescantia bracteata</i> Small and <i>Allium cepa</i> L. has been studied. An inhibition of the germination and of the growth of pollen tubes was observed, proportionally to the concentration of glycosides. The pollen grains of <i>A. cepa</i> are more sensitive. The disturbances in mitosis lead to the formation of two or more uneven-sized doughter nuclei, or to the formation of restitution nuclei. These anomalies are more numerous in <i>T. bracteata</i>. From these results d t appears that pollen grains of <i>A. cepa</i> are characterized by a generally high physiological sensitivity and a small mitotic sensitivity, wheras for <i>T. bracteata</i> the opposite is true.

scholarly journals PENAMBAHAN LARUTAN BAWANG MERAH (Allium cepa L.) DAN AIR KELAPA (Cocos nucifera L.) SEBAGAI FITOHORMON ALAMI PADA PERTUMBUHAN TANAMAN TEBU (Sacchanum officinarum L.) SEBAGAI SUMBER BELAJAR BIOLOGI

2020 ◽  
Vol 11 (2) ◽  
pp. 160
Author(s):  
Dewi Kurniawati ◽  
HRA Mulyani ◽  
Rasuane Noor
Keyword(s):  
Allium Cepa ◽  
Water Solution ◽  
Cocos Nucifera ◽  
Coconut Water ◽  
The Third ◽  
Randomized Design ◽  
Allium Cepa L ◽  
Number Of Leaves ◽  
The One ◽  
Cocos Nucifera L

This study aims to 1) to see the effect of natural phytohormones in onions and coconut water on the growth of sugarcane, 2) To see the effect of giving natural phytohormones to sugarcane plants which produce the best growth, 3) To see the results of research on the growth of sugarcane can be used biology learning resources. This type of research is an experimental study using a completely randomized design (CRD). This study consisted of 4 treatments, namely, the first treatment was giving sand and red soil, the second treatment was giving manure and 15% concentration of onion solution phytohormones, the third treatment was giving manure and phytohormones with 25% concentration of coconut water solution, the fourth treatment was Pembrian. Manure and phytohormone combined with 15% concentration of onion solution + phytohormone with 25% concentration of coconut water solution. The parameters observed in this study were height in units (cm), number of leaves (counting manually), stem diameter in units (cm). To determine the effect of phytohormone solutions on shallots and coconut water, data analysis was carried out using the one-way ANOVA test. and further tests to find out the most optimum treatment for the growth of sugarcane using the BNJ test. Based on the research, there was a significant effect of giving natural phytohormones on the growth of sugarcane, with the best treatment, namely the third treatment of giving manure and phytohormones of coconut water solution. The results of this research can be used as a source of learning biology in the form of videos with material on the growth and development of class XII. Kata kunci: larutan bawang merah (allium cepa L), air  kelapa (cocos nucifera L), fitohormon, tanamantebu.

scholarly journals The effect of the edein complex on the activity of apical root meristems of Allium cepa L.

2015 ◽  
Vol 44 (4) ◽  
pp. 589-595
Author(s):  
J. A. Tarkowska ◽  
K. B. Domańska
Keyword(s):  
Dna Synthesis ◽  
Allium Cepa ◽  
Water Solution ◽  
Bacterial Cells ◽  
Root Tips ◽  
Irreversible Damage ◽  
Allium Cepa L ◽  
Good Accordance ◽  
Meristematic Activity ◽  
Inhibition Of Dna Synthesis

The effect of a mixture of edeins in water solution on the meristematic activity of <em>Allium cepa</em> L. root tips was studied during the incubation and postincubation periods. Reduction of the elongation growth of the root tips and a strong decrease in. the number of mitoses was observed what, as cytochemical and autoradiographical studies have shown, is due to the inhibition of DNA synthesis. DNA synthesis is completely inhibited after 24 hrs of incubation. Changes caused by 25 ppm concentration of the solution are reversible during postincubation. The concentration of 50 ppm produces irreversible damage. The main direction of cytochemical changes caused by the action of edeins on the meristematic cells is in good accordance with those recorded for bacterial cells (Kuryło-Borowska 1962, Borowski and Chmara 1968).

Mitotic Effect of Water Extract of Different Ipomoea Species on Allium cepa L.

2006 ◽  
Vol 9 (6) ◽  
pp. 1116-1120 ◽  
Author(s):  
A. Mondal ◽  
G. Kabir ◽  
N. Yasmin ◽  
A.M.S. Alam ◽  
H.A. Khatun
Keyword(s):  
Allium Cepa ◽  
Water Extract ◽  
Effect Of Water ◽  
Allium Cepa L ◽  
Ipomoea Species

scholarly journals Notes on the self-pollination in Dendrobium biflorum (Orchidales, Dendrobiinae)

2012 ◽  
Vol 81 (3) ◽  
pp. 223-228 ◽  
Author(s):  
Agnieszka K. Kowalkowska ◽  
Hanna B. Margońska
Keyword(s):  
Pollen Grains ◽  
Weather Conditions ◽  
Pollen Tubes ◽  
French Polynesia ◽  
Growth Conditions ◽  
Society Islands ◽  
Self Pollination ◽  
Two Stages ◽  
Germination Of Pollen ◽  
First Time

The conditions favouring self-pollination are determined for a species of <em>Dendrobium </em>Sw. A survey of gynostemium micro­morphology in collected flowers of <em>Dendrobium biflorum </em>revealed two stages of a unique form of autogamy: on germination of pollen tetrads, pollen tubes reached the stigmatic region without the pollen being displaced from the anther locules. This is the first time for this type of autogamy to be reported in <em>Dendrobium biflorum</em>. Pollen grains germinated directly from the locules, bypassing the stigma or falling or sliding down onto the stigmatic surface. The pollen tubes were long and reached the stylar canal. On The Society Islands, differences in exposure of the habitats to weather conditions and altitude gradients influence both composition and form of the vegetation, as well as the occurrence of pollinators. The form of autogamy described here may be the usual method of pollination found on The Society Islands (and even the whole of French Polynesia), where suitable pollinators are absent and/or growth conditions stressful.

scholarly journals Effect of water extract from leaves of Nerium oleander L. on mitosis

2015 ◽  
Vol 40 (4) ◽  
pp. 623-631
Author(s):  
J. A. Tarkowska
Keyword(s):  
Electron Microscope ◽  
Allium Cepa ◽  
Mitotic Spindle ◽  
Water Extract ◽  
Water Soluble ◽  
Nerium Oleander ◽  
Root Tips ◽  
Meristematic Cells ◽  
Effect Of Water

The effect of water extract from leaves of <i>Nerium oleander</i> L. on the mitosis in meristematic cells of <i>Allium cepa</i> L. root tips has been studied. Observations were made on the changes during incubation and postincubation. Significant disturbances were observed in the development of the mitotic spindle leading to the formation of polyploid and hypoploid nuclei capable of further division. Substances contained in the water extract, and causing the disturbances, are water soluble glycosides. Introductory observations under an electron microscope indicate that the glycosides desorganize the continuous fibres of the spindle which can be considered as the direct cause of the observed disturbances.

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