scholarly journals Morphological Characteristics and In Situ Auxin Production during the Histogenesis of Staminate Flowers in Precocious Walnut

2014 ◽  
Vol 139 (2) ◽  
pp. 185-190 ◽  
Author(s):  
Ying Gao ◽  
Hao Liu ◽  
Dong Pei
Keyword(s):  
Juglans Regia ◽  
Staminate Flower ◽  
Morphological Characteristics ◽  
Histological Structure ◽  
Anther Wall ◽  
Auxin Production ◽  
Tapetal Cells ◽  
High Level ◽  
Stage 1 ◽  
Cellular Specialization

Monoclonal anti-indole acetic acid antibodies were used to monitor the temporal and spatial pattern of auxin during staminate flower differentiation in walnut (Juglans regia) cultivars Liaoning 1 and Liaoning 3. The relationship between morphological characteristics and histological structure was established. Seven stages of differentiation were recognized based on the visibility and color of the squama, bract, perianth, and rachis as follows: Stage 1, several bract primordia were present in the squama with catkins protruding from the squama as the only externally visible portion of the floret (Stage 1); the bract became externally visible, and the floret, perianth, and stamen primordia formed basipetally (Stage 2); the length of catkins were elongated, only bracts visible and getting brown (Stage 3); the bracts were brown and wrapped tightly, cellular specialization occurred to form a central core containing reproductive cells and tapetal cells that differentiated (Stage 4); the perianth became visible externally, reproductive cells and tapetal cells separated from the exterior layers of the anther wall (Stage 5); the anther walls were reduced to two cell layers (epidermis and endothecium) as the anthers became visible and matured (Stage 6); and the anther turned black, dehisced, and released its pollen grains (Stage 7). The histological differentiation of the flowers was related to auxin. The auxin signal was strongest in the shoot apical meristem (SAM) during bract primordia differentiation; thus, the SAM may be a site of auxin production. When the floral organs began centralized differentiation, auxin was distributed mainly in the differentiating tissues. Our findings indicate that a high level of auxin may strongly affect morphogenesis. Additionally, the tapetal and reproductive cells that arise during cellular specialization may be important for auxin production. The distribution of auxin was centralized in germ pores at the pollen grain surface, indicating that a high level of auxin induces pollen germination.

scholarly journals External Morphological Characteristics for Histogenesis in Pecan Anthers

1992 ◽  
Vol 117 (1) ◽  
pp. 181-189 ◽  
Author(s):  
I.E. Yates ◽  
Darrell Sparks
Keyword(s):  
Cellular Differentiation ◽  
Morphological Characteristics ◽  
Stage Iv ◽  
Pollen Grains ◽  
Stage I ◽  
Stage Ii ◽  
Anther Wall ◽  
Tapetal Cells ◽  
Cell Layers ◽  
Cellular Specialization

External “morphological characteristics of catkins from one protogynous (`Stuart') and one protandrous (`Desirable') cultivar of pecan [Carya illinoensis Wangenh.) C. Koch] were examined to define markers of cellular differentiation in the anthers. The angle between the catkin rachis and the bract, visibility of the bracteole, rachis, and anther, and anther color proved to be markers by which development could be categorized into five stages. `Stuart' catkins with bracts as the only externally visible portion of the floret (Stage I) commonly had two locules in each anther lobe. When bracteoles became externally visible (Stage II), cellular specialization had occurred to form a central core containing reproductive cells and tapetal cells differentiated and separated from the exterior layers of the anther wall. Disintegration of tapetal cells and thickening of endothecium eel! walls occurred as the angle between the rachis and bract increased to 45° (Stage III). The anther wall was reduced to only two cell layers, epidermis and endothecium, as the anthers became visible (Stage IV). The pollen grains were mature when the anthers developed a yellowish tinge (Stage V) just before anther dehiscence. Tapetal cells had developed distinguishing traits in anthers of Stage I `Desirable' catkins and endothecial cells of Stage II. Internal anther development was similar for both cultivars from Stages III-V. Trichomes, a common feature-on the surface of the staminate floral parts, became less dense with proximity of the floral parts to the interior of the floret and with catkin maturity.

scholarly journals Cytochemical and ultrastructural observations of anthers and pollen grains in Lathyrus undulatus Boiss

2011 ◽  
Vol 70 (1) ◽  
pp. 53-64 ◽  
Author(s):  
Filiz Vardar ◽  
Meral Ünal
Keyword(s):  
Morphological Characteristics ◽  
Pollen Grains ◽  
Middle Layer ◽  
Mature Pollen ◽  
Anther Wall ◽  
Tapetal Cells ◽  
Microspore Stage ◽  
Pollen Stage ◽  
Mature Anther ◽  
Insoluble Polysaccharides

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.

scholarly journals Features of the histological structure of the placenta in women with recurrent miscarriage depending on polymorphic variants of the metalloproteinase and hemostasis systems

2020 ◽  
Vol 17 (2) ◽  
pp. 158-169
Author(s):  
T. N. Grinevich ◽  
S. A. Lyalikov ◽  
V. A. Basinsky ◽  
T. T. Shtabinskaya ◽  
C. M. Butolina ◽  
...  
Keyword(s):  
Comparison Group ◽  
Recurrent Miscarriage ◽  
Morphological Characteristics ◽  
Reproductive Function ◽  
Placental Tissue ◽  
Histological Structure ◽  
Chorionic Villi ◽  
Intervillous Space ◽  
Reproductive Losses ◽  
Polymorphic Variants

The article is devoted to the analysis of the morphological characteristics of placental tissue in women with early reproductive losses with recurrent miscarriage, depending on the presence of polymorphic variants of metalloproteinases and hemostasis. It was established that in women with recurrent miscarriage, the area of the trophoblast of the placenta is significantly larger (р < 0.003), the area of the chorionic villi is smaller (р < 0.04) than in the group of women with implemented reproductive function. Thrombosis of the chorionic vessels, necrosis and calcinates in the placenta with PNF were detected in 80.0 % (р = 0.001), 93.3 % (р = 0.001), and 30.0 % (р = 0.049) of cases, respectively, which is significantly higher than in the comparison group. In patients with PNP with the T/T genotype of the 735 C/T polymorphism of the MMP-2 gene, the trophoblast area is significant (р < 0.05) more than with the C/C genotype, acute full-back (р = 0.02) and intervillous hemorrhage (р = 0.02). In women with the C/T genotype of the polymorphism 735 C/T of the MMP-2 gene, edema and dystrophic changes in the chorionic villi, placental necrosis are determined more often (р = 0.02) than with the C/C genotype. In carriers of the T allele of the polymorphism 735 C/T of the MMP-2 gene in the placenta, necrosis is significantly more common than in the CC genotype; the carriage of the T allele is also associated with large values of the relative area of the trophoblast and the stromal-intervillous relation, as well as with a smaller value of the ratio of the intervillous space area to the total area of the photograph.

scholarly journals Dynamics of Polysaccharides and Neutral Lipids during Anther Development in Castor (Ricinus communis)

2015 ◽  
Vol 140 (4) ◽  
pp. 356-361 ◽  
Author(s):  
Dongmei Wei ◽  
Huimin Xu ◽  
Ruili Li
Keyword(s):  
Neutral Lipids ◽  
Ricinus Communis ◽  
Starch Content ◽  
Single Layer ◽  
Pollen Grains ◽  
Middle Layer ◽  
Anther Development ◽  
Anther Wall ◽  
Starch Grains ◽  
Tapetal Cells

Anthers contain starch and neutral lipids, which have key roles in microspore ontogeny and gametophyte development. In this study, we observed the dynamic changes in starch and neutral lipids in the anther developmental processes of castor (Ricinus communis) by cytochemical methods. Starch grains and neutral lipids presented a regular dynamic distribution during anther development. In young anthers, some neutral lipids accumulated in sporogenous cells, whereas neutral lipids disappeared with microspore growth. At the late microspore stage, starch grains began to accumulate in microspores, and the starch content of bicellular pollen significantly increased after microspore mitosis. At anthesis, starch grains and neutral lipids accumulated in the mature pollen grains. Visible changes occurred in anther wall cells. The epidermis, middle layer, and tapetum were degenerated, and only a single layer of endothecium remained at anthesis. The dynamic variation of starch grains and neutral lipids in tapetal cells was consistent with the changes in microspores and pollen during anther development. All these findings demonstrated that tapetal cells directly interacted with the developing gametophytes. The tapetal cells play an important role in supplying nutritional substances for microspore absorption. Moreover, the endothecium protects the pollen and contributes to anther dehiscence. The results of this study provide a foundation for the further research on sexual reproduction in angiosperms.

scholarly journals Morphological evaluation of common bean diversity in Bosnia and Herzegovina using the discriminant analysis of principal components (DAPC) multivariate method

Genetika ◽  
2013 ◽  
Vol 45 (3) ◽  
pp. 963-977 ◽  
Author(s):  
Jasmin Grahic ◽  
Fuad Gasi ◽  
Mirsad Kurtovic ◽  
Lutvija Karic ◽  
Mirha Djikic ◽  
...  
Keyword(s):  
Discriminant Analysis ◽  
Common Bean ◽  
Bosnia And Herzegovina ◽  
Principal Components ◽  
Morphological Characteristics ◽  
Principal Component ◽  
Discriminant Functions ◽  
Factor Loadings ◽  
Geographical Regions ◽  
High Level

In order to analyze morphological characteristics of locally cultivated common bean landraces from Bosnia and Herzegovina (B&H), thirteen quantitative and qualitative traits of 40 P. vulgaris accessions, collected from four geographical regions (Northwest B&H, Northeast B&H, Central B&H and Sarajevo) and maintained at the Gene bank of the Faculty of Agriculture and Food Sciences in Sarajevo, were examined. Principal component analysis (PCA) showed that the proportion of variance retained in the first two principal components was 54.35%. The first principal component had high contributing factor loadings from seed width, seed height and seed weight, whilst the second principal component had high contributing factor loadings from the analyzed traits seed per pod and pod length. PCA plot, based on the first two principal components, displayed a high level of variability among the analyzed material. The discriminant analysis of principal components (DAPC) created 3 discriminant functions (DF), whereby the first two discriminant functions accounted for 90.4% of the variance retained. Based on the retained DFs, DAPC provided group membership probabilities which showed that 70% of the accessions examined were correctly classified between the geographically defined groups. Based on the taxonomic distance, 40 common bean accessions analyzed in this study formed two major clusters, whereas two accessions Acc304 and Acc307 didn?t group in any of those. Acc360 and Acc362, as well as Acc324 and Acc371 displayed a high level of similarity and are probably the same landrace. The present diversity of Bosnia and Herzegovina?s common been landraces could be useful in future breeding programs.

Phylogenetic differentiation and taxonomic consequences in the Saurodactylus brosseti species complex (Squamata: Sphaerodactylidae), with description of four new species

Zootaxa ◽  
2019 ◽  
Vol 4674 (4) ◽  
pp. 401-425
Author(s):  
SOHEILA JAVANMARDI ◽  
SVEN VOGLER ◽  
ULRICH JOGER
Keyword(s):  
Species Complex ◽  
Morphological Characteristics ◽  
Color Pattern ◽  
Distribution Area ◽  
12S Rrna ◽  
Ecological Traits ◽  
Acacia Species ◽  
Mitochondrial Markers ◽  
Dichotomous Key ◽  
High Level

We divide Saurodactylus brosseti into five species, based on molecular and morphological characteristics. Phylogenetic analysis of two mitochondrial markers (ND4 and 12S rRNA) reveals five separately evolving lineages (clades) in the S. brosseti species complex. Each can be assigned to a particular geographical range within the distribution area in Morocco: North, South, Anti-Atlas, East and Southeast. A dichotomous key for all species within the genus Saurodactylus is presented. Despite the high level of color pattern variation among and within the northern, southern, Anti-Atlas and eastern clades, the southeastern lineage shows a unique coloration which is not found in other clades. The ecological traits of the southeastern clade seem to differ from those of the other four lineages since it is basically associated with Acacia species. Like the relictual ecosystem characterized by these trees, it appears to be highly threatened by extinction. 

scholarly journals Monitoring Fungicide Sensitivity Levels and Mycelial Compatibility Groupings of Sclerotium rolfsii Isolates from Florida Peanut Fields

2017 ◽  
Vol 44 (2) ◽  
pp. 83-92 ◽  
Author(s):  
K. Khatri ◽  
S. Kunwar ◽  
R. L. Barocco ◽  
N. S. Dufault
Keyword(s):  
Management Practices ◽  
Phenotypic Diversity ◽  
Sclerotium Rolfsii ◽  
Morphological Characteristics ◽  
Morphological Diversity ◽  
Fungicide Sensitivity ◽  
Dose Effects ◽  
Mycelial Compatibility ◽  
Monitoring Survey ◽  
High Level

ABSTRACT Sclerotium rolfsii, the causal agent of peanut stem rot, is a diverse pathogen that has exhibited decreases in sensitivity to fungicides in areas where they are frequently applied. To better understand this pathogen's diversity and its response to various fungicides in Florida, a monitoring survey was done to examine isolates from several peanut producing areas using morphological characteristics, mycelial compatibility groupings and fungicide sensitivity profiles. A high level of morphological diversity was observed among a small number (N = 15) of isolates which was affirmed by both Shannon-Weiner (E = 0.812) and Simpson's (D = 0.280) indices. However, despite this high level of diversity, fungicide sensitivity of these isolates to flutolanil (EC50 = 0.031 ppm) and tebuconazole (EC50 = 0.008 ppm) appears to remain relatively unchanged when compared to a previous baseline study. Utilizing a small number of isolates, this monitoring survey indicated the EC50 values for the products azoxystrobin (EC50 = 0.050 ppm), prothioconazole (EC50 = 0.213 ppm), penthiopyrad (EC50 = 0.016 ppm) and solatenol (EC50 = 0.005 ppm). A trend for hormesis was also noted in this survey (e.g. flutolanil), but further research is necessary to better understand sub-lethal fungicide dose effects on increasing mycelial growth. It is apparent from these results that despite the high levels of phenotypic diversity in S. rolfsii populations, current fungicide management practices should remain effective for disease control.

Filogeni Timun Laut (Holothuroidea: Stichopodidae) Berdasarkan Karakteristik Morfologis

2016 ◽  
Vol 1 (2) ◽  
pp. 1
Author(s):  
Ismiliana Wirawati ◽  
Pradina Purwati
Keyword(s):  
Sea Cucumber ◽  
Morphological Characteristics ◽  
Shallow Waters ◽  
Internal Organs ◽  
Parsimony Method ◽  
Maximum Parsimony Method ◽  
Phylogeny Analysis ◽  
The Status ◽  
Commercial Species ◽  
High Level

<strong>Phylogeny of Sea Cucumbers (Holothuroidea: Stichopodidae) Based on Morphological Characteristics.</strong> Identifiers in the class of sea cucumber (Holothuroidea, Echinodermata) constitute the external morphology, internal organs, and spicules. These characteristics may indicate a high level of similarity for particular families, including family Stichopodidae. This family is one of the Holothuroidea (Echinodermata) that represents the majority of commercial species found widespread in the tropical shallow waters. Until now, the evolution of sea cucumber based on morphological characteristics used to determine the status of the characteristics applicable to the phylogeny analysis is still under debate. In fact, research on the phylogeny of Stichopodidae, has not been done yet. This paper reports the phylogeny study of Stichopodidae species in Indonesia to determine the closeness among its species. Specimens used in this study were the collection of Research Center for Oceanography LIPI consisting of nine species of Stichopodidae (as ingroup) and two species of Holothuriidae (as outgroup). The construction of phylogeny tree was done by applying the maximum parsimony method and PAUP 4.0b program using 78 morphological characteristics. It resulted in two phylogeny trees separating consistently the genus Stichopus from the genus Thelenota (bootstrap 99% and 100%) with the stable position in each genus. Both these genera of Stichopodidae have the same number of synapomorphs. Stichopus has ten homoplastic characteristics among its species, while Thelenota does not have any. Six of the nine species of Stichopodidae show autapomorph characteristics which are proper to species level<br />

scholarly journals First Report of Leaf Spot Disease on Walnut Caused by Colletotrichum fioriniae in China

Plant Disease ◽  
2015 ◽  
Vol 99 (2) ◽  
pp. 289-289 ◽  
Author(s):  
Y. Z. Zhu ◽  
W. J. Liao ◽  
D. X. Zou ◽  
Y. J. Wu ◽  
Y. Zhou
Keyword(s):  
Dna Sequences ◽  
Leaf Spot ◽  
Juglans Regia ◽  
Morphological Characteristics ◽  
Leaf Spot Disease ◽  
Koch’S Postulates ◽  
First Report ◽  
Spot Disease ◽  
Leaf Spots ◽  
Koch's Postulates

In May 2014, a severe leaf spot disease was observed on walnut tree (Juglans regia L.) in Hechi, Guangxi, China. Leaf spots were circular to semicircular in shape, water-soaked, later becoming grayish white in the center with a dark brown margin and bordered by a tan halo. Necrotic lesions were approximately 3 to 4 mm in diameter. Diseased leaves were collected from 10 trees in each of five commercial orchards. The diseased leaves were cut into 5 × 5 mm slices, dipped in 75% ethanol for 30 s, washed three times in sterilized water, sterilized with 0.1% (w/v) HgCl2 for 3 min, and then rinsed five times with sterile distilled water. These slices were placed on potato dextrose agar (PDA), followed by incubating at 28°C for about 3 to 4 days. Fungal isolates were obtained from these diseased tissues, transferred onto PDA plates, and incubated at 28°C. These isolates produced gray aerial mycelium and then became pinkish gray with age. Moreover, the reverse of the colony was pink. The growth rate was 8.21 to 8.41 mm per day (average = 8.29 ± 0.11, n = 3) at 28°C. The colonies produced pale orange conidial masses and were fusiform with acute ends, hyaline, sometimes guttulate, 4.02 to 5.25 × 13.71 to 15.72 μm (average = 4.56 ± 0.31 × 14.87 ± 1.14 μm, n = 25). The morphological characteristics and measurements of this fungal isolate matched the previous descriptions of Colletotrichum fioriniae (Marcelino & Gouli) R.G. Shivas & Y.P. Tan (2). Meanwhile, these characterizations were further confirmed by analysis of the partial sequence of five genes: the internal transcribed spacer (ITS) of the ribosomal DNA, beta-tubulin (β-tub) gene, glyceraldehyde 3-phosphate dehydrogenase (GAPDH) gene, chitin synthase 3(CHS-1) gene, and actin (ACT) gene, with universal primers ITS4/ITS5, T1/βt2b, GDF1/GDR1, CHS1-79F/CHS1-354R, and ACT-512F/ACT-783R, respectively (1). BLAST of these DNA sequences using the nucleotide database of GenBank showed a high identify (ITS, 99%; β-tub, 99%; GAPDH, 99%; CHS-1, 99%; and ACT, 100%) with the previously deposited sequences of C. fioriniae (ITS, KF278459.1, NR111747.1; β-tub, AB744079.1, AB690809.1; GAPDH, KF944355.1, KF944354.1; CHS-1, JQ948987.1, JQ949005.1; and ACT, JQ949625.1, JQ949626.1). Koch's postulates were fulfilled by inoculating six healthy 1-year-old walnut trees in July 2014 with maximum and minimum temperatures of 33 and 26°C. The 6-mm mycelial plug, which was cut from the margin of a 5-day-old colony of the fungus on PDA, was placed onto each pin-wounded leaf, ensuring good contact between the mycelium and the wound. Non-colonized PDA plugs were placed onto pin-wounds as negative controls. Following inoculation, both inoculated and control plants were covered with plastic bags. Leaf spots, similar to those on naturally infected plants, were observed on the leaves inoculated with C. fioriniae within 5 days. No symptoms were observed on the negative control leaves. Finally, C. fioriniae was re-isolated from symptomatic leaves; in contrast, no fungus was isolated from the control, which confirmed Koch's postulates. To our knowledge, this is the first report of leaf disease on walnut caused by C. fioriniae. References: (1) L. Cai et al. Fungal Divers. 39:183, 2009. (2) R. G. Shivas and Y. P. Tan. Fungal Divers. 39:111, 2009.

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