scholarly journals THE QUALITY OF POLLEN GRAINS IN WHEAT MATURE ANTHERS OF ZHNITSA CULTIVAR IN PLANTA CONDITIONS

ÈKOBIOTEH ◽  
2021 ◽  
Vol 4 (1) ◽  
pp. 24-32
Author(s):  
A.E. Zinatullina ◽  

Biotechnological and selection investigations for making of wheat high-yielding resistant varieties require a significant amount of high-quality mature pollen. It is important to assess It is important to assess the quality of pollen grains in mature anthers in planta of the wheat genotypes included in the experiments. In the course of research the analysis of the histological status of mature anthers was carried out and qualitative cytological evaluation inside them pollen grain of spring soft wheat Zhnitsa cultivar was done in in planta conditions. It was shown that the structure of the wall locule anther presented by exothecium and endothecium is typical for cereals. It was established that 3-cell mature pollen grains are fertile (87-92%) and viable (75–80%) in general. At the same time in every mature anther abnormal pollen grains were observed and the cellular, nuclear, cytoplasmic and architectonic deviations from the norm were revealed. On the base of literature date the analysis of the reasons for the formation of abnormal pollen grains in planta was done and the classification of anomalies of plant pollen grains and the terminology used in this field of research were discussed.

2007 ◽  
Vol 132 (6) ◽  
pp. 777-782 ◽  
Author(s):  
Zhiyong Hu ◽  
Min Zhang ◽  
Qigen Wen ◽  
Jie Wei ◽  
Hualin Yi ◽  
...  

Seedlessness is of commercial importance in citrus (Citrus L.). Seedless ‘Ougan’ mandarin (C. suavissima) was selected from a bud sport mutation that occurred in ‘Ougan’ mandarin. We analyzed their pollen viability through KI-I2 and FDA staining, and examined the anthers of wild-type (seedy) and seedless mutant ‘Ougan’ mandarin using histological and cytochemical methods to characterize the process of pollen development. No pollen fertility was detected in this mutant. Pollen abortion in anthers of the mutant occurred at the tetrad stage of microspore development, and almost all the tetrads were abnormal. The mutant had heterogeneous microspore populations, including monads, dyads, triads, tetrads, and polyads in the same microsporangium. Pollen grain number per anther of the mutant was 21.9% less than the wild type. Morphology of mature pollen grains using SEM showed that the shape of mature pollen grains from both wild type and mutant is similar, but the microsporangia of the latter contained pollen grains of more variable sizes. At the early mature pollen grain stage, abundant starch grains and lipids appeared in the wild type's pollen, but fewer amounts were observed in the mutant. Moreover, the tapetal cells of the wild type accumulated lipids, but not those of the mutant. Results indicated that the abnormal development of the microspore led to pollen abortion in the mutant, and this could be the reason for its seedlessness. However, the genetic reasons for the aberrant tetrads are not clear and are under investigation.


2020 ◽  
Vol 18 (4) ◽  
pp. 23-31
Author(s):  
D.F. Askhadullin ◽  
◽  
D.F. Askhadullin ◽  
N.Z. Vasilova ◽  
E.Z. Bagavieva ◽  
...  

The effect of fungicide class strobilurine on "effect gardening" plants is undeniable. Most research on this class of drugs focuses on their effects on plant growth and physiology. There is little information about the effect of strobilurine on the rheological properties of the dough when applied to wheat. In our work, we tried to identify their role. The objects of the study were 5 varieties of spring soft wheat, with different grain and flour quality. To study the effect strobilurins was selected fungicide containing pyraclostrobin + epoxiconazole. The use of a preparation based on pyraclostrobin does not lead to a strong change in the grain quality and rheological properties of the dough in rust-resistant varieties, this indicates that strobilurins almost do not affect the grain quality. In varieties that are highly and medium susceptible to leaf-stem diseases, not only the yield increases significantly, but also the grain quality and rheological properties of the test improve when using a fungicide based on pyraclostrobin 62.5 g/l + epoxiconazole 62.5 g/l at a dose of 1.5 l/ha.


2019 ◽  
Author(s):  
Bruno Aristimunha ◽  
Felipe Silveira Brito Borges ◽  
Ariadne Barbosa Gonçalves ◽  
Hemerson Pistori

The classification of pollen grains images are currently done manually and visually, being a weariful task and predisposed to mistakes due to human exhaustion. In this paper, the authors introduce an automatic classification of 55 different pollen grain classes, using convolutional neural networks. Different architectures and hyperparameters were used to improve the classification result. Using the networks VGG16, VGG19, and InceptionV3, were obtained accuracy rates over 93.58%.


Author(s):  
N. N. Kruglova

The review article analyzes the literature and own data on the possible causes of the formation of abnormal pollen grains in flowering plants and methods for assessing the quality of pollen. Classification of anomalies of developing pollen grains is given. The terminology used is discussed.


2011 ◽  
Vol 70 (1) ◽  
pp. 53-64 ◽  
Author(s):  
Filiz Vardar ◽  
Meral Ünal

Cytochemical and ultrastructural observations of anthers and pollen grains inLathyrus undulatusBoissInLathyrus undulatusBoiss. (Fabaceae), the young microspore stage of anther development was characterized by the enlarged secretory tapetal cells, which presented an intense reaction with regard to protein, insoluble polysaccharides and lipids. At bicellular pollen stage, the middle layer and the tapetum degenerated. After degradation of the tapetum, epidermis and single row U-shaped endothecium existed in the mature anther wall, and pollen grains remained in the locus. Young microspores had a spherical and centrally located nucleus with one or two nucleoli, many spherical lipid bodies and starchy plastids. A mature pollen grain contains insoluble polysaccharides, proteins, lipids and calcium. The mature pollen had the following morphological characteristics: 3-zonocolporate, prolate, tectate (imperforate) type of exine and perforate type of structure. The intine formed an important constituent portion of the wall, and consisted two sublayers: an outer intine (exintine) and an inner intine (endintine). The well-defined exine was made up of lipoidal substances and protein, but the intine composed of insoluble polysaccharides and protein. The bicellular state of the pollen grains persisted to anthesis.


2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Siavash Iravani ◽  
Rajender S. Varma

Abstract Pollen grains and plant spores have emerged as innovative biomaterials for various applications such as drug/vaccine delivery, catalyst support, and the removal of heavy metals. The natural microcapsules comprising spore shells and pollen grain are designed for protecting the genetic materials of plants from exterior impairments. Two layers make up the shell, the outer layer (exine) that comprised largely of sporopollenin, and the inner layer (intine) that built chiefly of cellulose. These microcapsule shells, namely hollow sporopollenin exine capsules have some salient features such as homogeneity in size, non-toxic nature, resilience to both alkalis and acids, and the potential to withstand at elevated temperatures; they have displayed promising potential for the microencapsulation and the controlled drug delivery/release. The important attribute of mucoadhesion to intestinal tissues can prolong the interaction of sporopollenin with the intestinal mucosa directing to an augmented effectiveness of nutraceutical or drug delivery. Here, current trends and prospects related to the application of plant pollen grains for the delivery of vaccines and drugs and vaccine are discussed. "Image missing"


2010 ◽  
Vol 82 (4) ◽  
pp. 893-902 ◽  
Author(s):  
Ortrud M. Barth ◽  
Alex S. Freitas ◽  
Érika S. Oliveira ◽  
Rosana A. Silva ◽  
Fernanda M. Maester ◽  
...  

High quality of bee pollen for commercial purpose is required. In order to attend the consumer with the best identification of the botanical and floral origin of the product, 25 bee pollen batches were investigated using two techniques of pollen grain preparation. The first started to identify pollen loads of different colors in two grams of each well mixed batch, and the second to identify pollen grains in a pool made of all the pollen loads comprised in two grams. The best result was obtained by this last technique, when a pollen grain suspension was dropped on a microscope slide and circa 500 pollen grains were counted per sample. This analysis resulted in the recognition of monofloral and bifloral pollen batches, while the use of the first technique resulted in all samples receiving a heterofloral diagnosis.


1998 ◽  
Vol 2 ◽  
pp. 115-122
Author(s):  
Donatas Švitra ◽  
Jolanta Janutėnienė

In the practice of processing of metals by cutting it is necessary to overcome the vibration of the cutting tool, the processed detail and units of the machine tool. These vibrations in many cases are an obstacle to increase the productivity and quality of treatment of details on metal-cutting machine tools. Vibration at cutting of metals is a very diverse phenomenon due to both it’s nature and the form of oscillatory motion. The most general classification of vibrations at cutting is a division them into forced vibration and autovibrations. The most difficult to remove and poorly investigated are the autovibrations, i.e. vibrations arising at the absence of external periodic forces. The autovibrations, stipulated by the process of cutting on metalcutting machine are of two types: the low-frequency autovibrations and high-frequency autovibrations. When the low-frequency autovibration there appear, the cutting process ought to be terminated and the cause of the vibrations eliminated. Otherwise, there is a danger of a break of both machine and tool. In the case of high-frequency vibration the machine operates apparently quiently, but the processed surface feature small-sized roughness. The frequency of autovibrations can reach 5000 Hz and more.


2020 ◽  
Vol 45 (4) ◽  
pp. 794-801
Author(s):  
Caroline Oliveira Andrino ◽  
Marcelo Fragomeni Simon ◽  
Jair Eustáquio Quintino Faria ◽  
André Luiz da Costa Moreira ◽  
Paulo Takeo Sano

Abstract—We describe and illustrate Paepalanthus fabianeae, a new species of Eriocaulaceae from the central portion of the Espinhaço Range in Minas Gerais, Brazil. Previous phylogenetic evidence based on analyses of nuclear (ITS and ETS) and plastid (trnL-trnF and psba-trnH) sequences revealed P. fabianeae as belonging to a strongly supported and morphologically coherent clade containing five other species, all of them microendemic, restricted to the Espinhaço range. Due to the infrageneric classification of Paepalanthus being highly artificial, we preferred not assigning P. fabianeae to any infrageneric group. Paepalanthus fabianeae is known from two populations growing in campos rupestres (highland rocky fields) in the meridional Espinhaço Range. The species is characterized by pseudodichotomously branched stems, small, linear, recurved, and reflexed leaves, urceolate capitula, and bifid stigmas. Illustrations, photos, the phylogenetic position, and a detailed description, as well as comments on habitat, morphology, and affinities with similar species are provided. The restricted area of occurrence allied with threats to the quality of the habitat, mainly due to quartzite mining, justifies the preliminary classification of the new species in the Critically Endangered (CR) category using the guidelines and criteria of the IUCN Red List.


2020 ◽  
Vol 6 (3) ◽  
pp. 158-164
Author(s):  
Navruza Yakhyayeva ◽  

The quality and content of information in the article media text is based on scientific classification of linguistic features. The study of functional styles of speech, the identification of their linguistic signs, the discovery of the functional properties of linguistic units and their separation on the basis of linguistic facts is one of thetasks that modern linguistics is waiting for a solution. Text Linguistics, which deals with the creation, modeling of its structure and the study of the process of such activity, is of interest to journalists today as a science.


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