vegetative origin
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2020 ◽  
Vol 11 (2) ◽  
pp. 53-65
Author(s):  
Y. Yu. Khan ◽  
О. P. Bala

Sustainable forest management, which based on the balance of ecological, economic and social aspects, requires a continuous updating and developing tools of objective assessment of the current state and further prediction changes of all elements of the forest ecosystem. Currently, questions related to the forecasting in the forestry is very important for actualization the databases in cases when using the continuous forest inventory. Vegetative origin oak stands play an important role in forming natural ecosystems in the Ukrainian forest-steppe zone. They represent 26 percent of all oak stands area, and, therefore, the question related to the growth modelling of biometric indices will be important in the future. The purpose of this research was to develop the growth models based on yield tables for the main biometric indices, such as: mean height, mean diameter, cross-sectional area per 1 ha and growing stock per 1 ha. Growth models for forecasting all specified biometric indices was based on the ratio of biometric index for the year ahead to the same index now taken from the forest growth tables for modal vegetative origin oak stands across dynamical site classes and the geographical location. The description of the obtained results was based on the lognormal density distribution function. The main parameters of mathematical models for the forecasting biometric indices were set using the nonlinear regression function via the IBM SPSS statistics software. Graphical and analytical methods were used for comparing the study results and analysing the obtained data. As a result of the study, the coefficients of the equation were obtained, which with sufficient accuracy describe the studied relations and forecasting the growth of stands according to the main biometric indices in the different age intervals. The deviation of growth modelling results for the main biometric indices, exhibit acceptable levels when compared to yield tables for vegetative origin Oak stands of the Ukrainian forest-steppe zone during all forecasting period and in percentage values are less than 1%, but for forecasting the stock per 1 ha for young forests the deviation can approach 4%. The forecasting period should preferably not exceed 10-15 years.


2020 ◽  
Vol 24 ◽  
pp. 00019
Author(s):  
Gulnora Denisova

The structure and development pattern of endemic of Baikal Siberia Dracocephalum popovii T.V. Egorova et Sipliv were studied in Buryatia. The base of the shoot system of adults is made up of branched and unbranched bi-tricyclical root-elongated and monocyclical elongated monocarpic shoots. Ontogenesis of individuals of D. popovii – full, difficult also consists of ontogenesis of a seed individual and the reduced ontogeneses of affiliated individuals. Individuals of a vegetative origin are represented by partial branched and unbranched shoots with an adventitious root system. Every year, the aboveground part of the individual completely dies, the shoot formation occurs due to the kidneys of the geophilic part of the bi-tricyclical rhizome-elongated shoots.


2020 ◽  
Vol 24 ◽  
pp. 00039
Author(s):  
Irina Konovalova ◽  
Natalya Savinykh

The paper demonstrates S. dulcamara ecobiomorphs: a long rhizome semi-woody liana (LSL), a long rhizome subshrub with ascending shoots (LSAS), a root sucker subshrub and a shortlived plants of vegetative origin; and ontobiomorphs: a taproot upright subshrub (TUS), a subshrub with a mixed root system (SMRS), LSL, and LSAS. Possible stages and modes are suggested of Solanum biomorph transformation: 1. TUS, as a result of prolongation on the shoot (adventitious roots) and shoot system level (two or more replacement shoots), deviations on individual plant level (shoot lodging), transforms into SMRS; 2. SMRS, through the plant’s ontogenesis abbreviation (fragmentation), prolongation (epigeogenum rhizome), and deviation (stem twisting), transforms into LSL. Further LSL habit transformations can occur in xerophylous and hygrophylous biomorph evolution lines. On dry soil, as a result of prolongation (adventitious buds on roots), a root sucker subshrub appears. A hygrophyle line is possible in case of prolongations on the shoot level (metamere number increase within a shoot, dicyclic shoots), of the individual plant abbreviations (shortened life-time of sympodial axes, early fragmentation) and end with a short-lived plants of vegetative origin. Possibly, mien changes in S. dulcamara ontogenesis show possible stages in Solanum life forms transformation, from tree forms to LSL.


2019 ◽  
Vol 10 (1) ◽  
pp. 136-146
Author(s):  
E. A. Belyakov ◽  
A. G. Lapirov

Representatives of the Sparganium L. genus belong to an ecological group of short grass helophytes which live in the shoreline area of different water bodies. Despite the fact that most representatives of the genus exhibit notable polymorphism (depending on the level regime of a water body, they can form various ecological forms), characteristic of all of them is presence of only one living form – vegetative mobile clear polycentric long-rhizomatous pseudoannual polycarpic plant with racemose root system. The objective of the article was to study the ontogenesis of genets and ramets on the example of representatives of the Xanthosparganium subgenus (S. emersum Rehm., S. glomeratum (Laest. ex Beurl.) Neum., S. gramineum Georgi and S. natans L.). The research was conducted using the ontogenetic approach. In the study, we analyzed ontogenesis of genet (from generative diaspore) and ontogenesis of ramets (from vegetative diaspores – tuber-like structures and axillary buds of vegetative-generative monocarpic and vegetative rosette shoots). We demonstrated that ontogenesis of genets and ramets (on the basis of tuber-like structures) in laboratory conditions is abrupt. It was found that the model species of Sparganium are characteristic in combining of incomplete and special ontogenesis, which is related to the omission of phases of the post-generative period. Such peculiarity is conditioned by increase in tempi of ontogenetic development. On the basis of specific ontogenesis, a variant of shortened ontogenesis is possible, during which the virginile ontogenetic condition is omitted. This feature could be characterized as dynamic polyvariance of ontogenesis, whereas bud initiation and development of shoots throughout the vegetative season, characterized as heterochrony, has been formed over the process of natural selection. Heterochrony (on the basis of iterative branching without periods of rest) includes a property of formation of vegetative-generative shoots which develop on the basis of sylleptic shoots of subsequent orders of branching. The main course of ontogenesis in natural conditions corresponds to D-type which occurs in order of generations of individuals of vegetative origin.


Author(s):  
Х.М. Хетагуров

Кленовники Северного Кавказа – особый тип лесных формаций. Особенность проявляется не только в структуре фитоценозов, но и в способах самовозобновления. Объект исследования – чистые и смешанные кленовники в нескольких урочищах РСО-Алания. Объекты расположены в различных условиях горного рельефа и на разной высоте над уровнем моря, от 1100 до 1900 м. Целью исследования является установление особенностей семенного возобновления кленовников, произрастающих в верхнем поясе распространения лесов на Северном Кавказе. Для достижения поставленной цели устанавливали время цветения и созревания семян по вертикальным поясам распространения кленовников. Обилие цветения и средний балл плодоношения устанавливали по В.Г. Капперу. Биометрические характеристики семян определяли по урочищам в трех повторностях. Учет подроста проводили на круговых учетных площадках по 10 м2, в соответствии с методикой А.В. Грязькина. Установлено, что цветение клена Траутфеттера начинается 10–14 мая и заканчивается в третьей декаде мая. Семена начинают созревать к концу августа – к началу сентября. Сроки опадения семян растянуты. Часть семян попадает на почву до начала листопада, поэтому они оказываются погребенными под опадом. Такие семена быстро теряют всхожесть, выпревают. Другая часть опадает вместе с листьями. Третья категория семян (самые легкие) держатся на деревьях до декабря и даже до весны. Естественное возобновление клена семенами под пологом материнского древостоя сильно затруднено из-за мощного травяного покрова. В древостое с сомкнутым пологом доля цветущих и плодоносящих деревьев составляет 2–3%, а средний балл плодоношения составляет 1,3. Освещенность на поверхности почвы не превышает 100 люкс, т. е. составляет 0,2–0,3% от освещенности на открытом месте; на высоте 1,3 м (над травостоем) освещенность несколько выше – от 1,2 до 1,6 тыс. люкс. Под пологом древостоя преобладает подрост вегетативного происхождения. У верхней границы кленового леса подрост семенного происхождения встречается в окнах, прогалинах и на открытых местах в количестве 430–630 экз./га. По высоте преобладает крупный подрост 50–60%, доля мелкого – 10–20%. The maple stands of the North Caucasus – a special type of forest formations. The peculiarity is manifested not only in the structure of phytocoenoses, but also in the ways of self-renewing. Object of research – pure and mixed maple stands in some areas of North Ossetia-Alania. The properties are located in various mountainous terrain and at different heights above sea level from 1100 to 1900 m. The aim of the study is to establish the characteristics of the seed the resumption of the maple stands growing in the upper belt of forests spread in the Northern Caucasus. To achieve this goal setting time of flowering and ripening of seeds on vertical zones distribution dominated. The abundance of flowering and the average score of fruiting was established by V.G. Capper. Biometric characteristics of the seeds was determined by the tracts in three replicates. Accounting for the undergrowth was carried out on a circular experimental plots at 10 m2, in accordance with the method of A.V. Grashkin. It is established that the flowering maple Trautvetter begins may 10–14 and ends in the third week of may. Seeds begin to ripen by late August – early September. The timing of subsidence of the stretched seed. Some of the seeds falls to the ground before the leaves, so they are trapped under the litter. These seeds quickly lose their germination, vypivaet. The other part falls along with the leaves. The third category of seeds (the light) stay on the trees until December and even till spring. Natural regeneration of maple seeds under the canopy of parent stand is very difficult due to the strong grass cover. In forest stands with dense canopy, proportion of flowering and fruit-bearing trees is 2–3%, and the average score of fruiting is 1.3. The illumination on the surface of the soil does not exceed 100 Lux, i. e. 0.2–0.3% of the light in the open, at a height of 1.3 m (on grass) the lighting is slightly higher, from 1.2 to 1.6 thousand Suite. Under the canopy of the forest the undergrowth is dominated by vegetative origin. At the upper boundary of the maple forest, saplings of seed origin occurs in Windows, clearings and open places in the number 430–630 ind./ha. In height dominated by large undergrowth of 50–60%, the share of small – 10–20%.


2014 ◽  
Vol 62 (1-2) ◽  
pp. 91-99
Author(s):  
Anna Namura-Ochalska

The survival, seedling and juvenile growth rates and the effectiveness of development and renewal of individuals obtained from seeds and rhizomes were studied. The results showed that the success of <i>Tussilago farfara</i> L. in colonizing disturbed environments, after its seeds reach the site and germinate, is a function of several of the important traits of this species: 1) tolerance of seedlings and juveniles to a wide range of changeable external conditions, 2) fast growth and development of individuals, 3) a high degree of adaptability in reaching successive stages of development, 4) querilla type growth, 5) intense spreading and renewal of individuals of generative and vegetative origin, 6) high effectiveness of vegetative reproduction, 7) adaptable allocation of resources to above-, and underground shoots.


2013 ◽  
Vol 04 (03) ◽  
pp. 078-081 ◽  
Author(s):  
Mona Dhakal ◽  
Om Prakash Dhakal ◽  
Mingma Sherpa ◽  
Amlan Gupta ◽  
Dhurba Bhandari

AbstractA granuloma is an organized and compact mass of mature mononuclear phagocytes. Granulomas are reported to form in various organs and sites of the body. Granulomas in stomach are rarely encountered. Foreign body granulomas are formed as a result of reaction of the tissues to a foreign body which is immunologically inert. Food granuloma is type of foreign body granuloma which is formed in response to food particles like vegetable matters or cereals. These granulomas can be distinguished from other types of granulomas with ease because of their characteristic morphologic features. We report the case of a 29-year-old male who developed a large gastric ulcer as a result of foreign body–induced giant cell reaction, which was probably of vegetative origin. He was treated with the regimen for Helicobacter pylori, rabeprazole and sucralfate. This treatment resulted in partial healing of the ulcer with persistence of food granuloma; hence, the patient was referred for surgery.


Bothalia ◽  
1991 ◽  
Vol 21 (1) ◽  
pp. 67-72 ◽  
Author(s):  
F. Albers ◽  
U. Meve

Mixoploidy is common in proembryos and embryos as well as in meristems of radicles, primary, secondary and adventitious roots and in innovation shoots of stapeliad species (Asclepiadaceae). The proportion of polyploid cells in the meristem of single adventitious roots is significantly higher than in meristems of primary and secondary roots. This may lead to a complete polyploidisation of adventitious roots. Innovation shoots display a low percentage of polyploid cells, comparable to the condition found in primary and secondary roots. Nevertheless cells of different euploid levels are frequently found. During field studies, however, individuals of a given population were always found to have the same chromosome number: infraspecific polyploidy was found in only three out of 305 investigated stapeliad species. Genera with an orthotropic growth form were found to be diploid throughout, whereas the genera of which the members spread vegetatively by means of innovation shoots, comprise di-, tetra- and polyploid species. This phenomenon can be ascribed to ecological rather than morphological factors. The often proposed hypothesis that new cytotypes can have a vegetative origin is not found to be acceptable.


1933 ◽  
Vol 78 (1) ◽  
pp. 88
Author(s):  
h Misc ◽  
l Misch-Frank
Keyword(s):  

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