scholarly journals Adaptation and Evolution of Seed Shape on Bleeding Area in Japanese Orchids

2012 ◽  
Vol 4 (2) ◽  
Author(s):  
Noriko Shimizu ◽  
Yutaka Sawa ◽  
Shinichiro Sawa
Keyword(s):  
1973 ◽  
Vol 30 (02) ◽  
pp. 363-370
Author(s):  
D Thilo ◽  
E Böhm

SummaryExperiments with injury of the abdominal rat skin were carried out to examine the haemostatic system mechanism in vivo after zero to 30 seconds bleeding time. In the bleeding area only a few platelet aggregates could be found with no primary platelet thrombus. After 3.5 second bleeding time the first fibrin strands have been observed at the site of injury. The hypothesis is put forward that there is a very fast reacting haemostatic mechanism which results in the fibrin formation already at 3.5 seconds.


2019 ◽  
Vol 104 (1) ◽  
pp. 33-48 ◽  
Author(s):  
Alejandro Zuluaga ◽  
Martin Llano ◽  
Ken Cameron

The subfamily Monsteroideae (Araceae) is the third richest clade in the family, with ca. 369 described species and ca. 700 estimated. It comprises mostly hemiepiphytic or epiphytic plants restricted to the tropics, with three intercontinental disjunctions. Using a dataset representing all 12 genera in Monsteroideae (126 taxa), and five plastid and two nuclear markers, we studied the systematics and historical biogeography of the group. We found high support for the monophyly of the three major clades (Spathiphylleae sister to Heteropsis Kunth and Rhaphidophora Hassk. clades), and for six of the genera within Monsteroideae. However, we found low rates of variation in the DNA sequences used and a lack of molecular markers suitable for species-level phylogenies in the group. We also performed ancestral state reconstruction of some morphological characters traditionally used for genera delimitation. Only seed shape and size, number of seeds, number of locules, and presence of endosperm showed utility in the classification of genera in Monsteroideae. We estimated ancestral ranges using a dispersal-extinction-cladogenesis model as implemented in the R package BioGeoBEARS and found evidence for a Gondwanan origin of the clade. One tropical disjunction (Monstera Adans. sister to Amydrium Schott–Epipremnum Schott) was found to be the product of a previous Boreotropical distribution. Two other disjunctions are more recent and likely due to long-distance dispersal: Spathiphyllum Schott (with Holochlamys Engl. nested within) represents a dispersal from South America to the Pacific Islands in Southeast Asia, and Rhaphidophora represents a dispersal from Asia to Africa. Future studies based on stronger phylogenetic reconstructions and complete morphological datasets are needed to explore the details of speciation and migration within and among areas in Asia.


HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 547b-547
Author(s):  
Soon O. Park ◽  
Dermot P. Coyne ◽  
Geunhwa Jung ◽  
E. Arnaud-Santana ◽  
H. Ariyarathne

Seed size is an important trait in common bean. The objective was to identify RAPD markers associated with QTL for seed weight, seed length, and seed height in a molecular marker-based linkage map in a recombinant inbred (RI) population from the common bean cross of the larger seeded (100 seed/39 to 47 g) PC-50 (ovate seed shape) × smaller seeded (100 seed/26 to 35 g) XAN-159 (flat rhomboidal seed shape). The parents and RI lines were grown in two separate greenhouse and two field (Wisconsin, Dominican Republic) experiments using a RCBD. Continuous distributions for seed weight, seed length, and seed height were observed for RI lines indicating quantitative inheritance. One to three QTLs affecting seed weight explained 17% to 41% of the phenotypic variation. Two to three QTLs for seed length explained 23% to 45% of the phenotypic variation. One to four QTL associated with seed height explained 17% to 39% of the phenotypic variation. A RAPD marker M5.850 in linkage group 3 was consistently associated with seed weight, seed length, and seed height in all experiments and explained 7% to 13% of the phenotypic variation for these traits. A seedcoat pattern morphological marker (C) in linkage group 1 was associated with seed weight and seed height in two greenhouse experiments.


Biomolecules ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 515
Author(s):  
Zhenhua Liu ◽  
Yan Wang ◽  
Wenjiang Pu ◽  
Haifeng Zhu ◽  
Jinjun Liang ◽  
...  

For some horticultural plants, auxins can not only induce normal fruit setting but also form fake seeds in the induced fruits. This phenomenon is relatively rare, and, so far, the underlying mechanism remains unclear. In this study, “Fenghou” (Vitis vinifera × V. labrusca) grapes were artificially emasculated before flowering and then sprayed with 4-CPA (4-chlorophenoxyacetic acid) to analyze its effect on seed formation. The results show that 4-CPA can induce normal fruit setting in “Fenghou” grapes. Although more seeds were detected in the fruits of the 4-CPA-treated grapevine, most seeds were immature. There was no significant difference in the seed shape; namely, both fruit seeds of the grapevines with and without 4-CPA treatment contained a hard seed coat. However, the immature seeds lacked embryo and endosperm tissue and could not germinate successfully; these were considered defective seeds. Tissue structure observation of defective seeds revealed that a lot of tissue redifferentiation occurred at the top of the ovule, which increased the number of cell layers of the outer integument; some even differentiated into new ovule primordia. The qRT-PCR results demonstrated that 4-CPA application regulated the expression of the genes VvARF2 and VvAP2, which are associated with integument development in “Fenghou” grape ovules. Together, this study evokes the regulatory role of 4-CPA in the division and continuous redifferentiation of integument cells, which eventually develop into defective seeds with thick seed coats in grapes.


1994 ◽  
Vol 6 (3) ◽  
pp. 385 ◽  
Author(s):  
Karen M. Leon-Kloosterziel ◽  
Christian J. Keijzer ◽  
Maarten Koornneef
Keyword(s):  

2021 ◽  
Author(s):  
Shulin Wang ◽  
Fujiang Hou

Abstract Aims Viable seeds in herbivore dung constitute the dung seed bank, and the contribution of livestock dung to this seed bank in grazing pastures is often overlooked. Grazing season (warm and cold), seed characteristics (size and shape), and forage preference are the main factors that affect the size and composition of the dung seed bank and ultimately affect grassland ecology. However, how these three factors interact is unclear. Methods We collected yak dung as well as seeds of the common plant species from warm- and cold-season alpine meadows in northeastern Qinghai-Tibetan Plateau, and explored how grazing season (warm and cold), seed characteristics (size and shape) and foraging preferences (temporary cages method) affects yak dung seedling density, richness and diversity in an alpine pasture. Results Forty-three plant species (mainly perennials) germinated from yak dung. Dung seedling density, richness, and diversity did not differ significantly between the two grazing seasons. Small to medium-sized spherical seeds (seed size < 10 mg, shape index < 0.5) had the greatest germination potential. Conclusions Yaks vary their forage preference depending on the season (phenological period), and endozoochory occurs throughout both grazing seasons. Seed shape and size directly regulate the dung seedling density, richness, and diversity. Dung seedlings increase the heterogeneity of the aboveground vegetation near the microsites of the dung pieces and therefore promote grassland patching. Our study demonstrates that grazing season, seed characteristics, and yak forage preferences affect the dung seed bank in grazing ecosystems.


2017 ◽  
Vol 35 (0) ◽  
Author(s):  
E. ALÇITEPE ◽  
S. ERKEN ◽  
F. GÜLBAG ◽  
M.E. ÖZZAMBAK

ABSTRACT Seeds of eleven perennial Gentiana collected from Turkey were analyzed using the SEM method. Other species excluding G. septemfida, G. boissieri, G. gelida were studied for the first time. They were identified and compared in terms of seed characteristics and surface ornamentations. Major characteristics including the outer periclinal walls of testa, sculpting of inner periclinal walls, seed shape, seed and testa cell, wing cell size, thickness of testa wall and seed shape have been proposed for Turkey Gentiana. They are divided into different types, such as no wing, chalazal wing, incomplete discoid wing, complete discoid wing according to the outer periclinal walls of testa. Considering primary sculpting of seeds, irregularly striate and shallowly reticulate type is observed. Anticlinal walls of G. olivieri, G. boissieri and G. gelida are curved, while others are straight. G. lutea has the largest mean seed (4.20 x 4.40 mm), while G. cruciata (0.67 x 0.60 mm) and G. olivieri have the smallest mean seeds (0.67 x 0.67 mm). Seed micromorphology can be used together with morphological character to form classifications in studied specimens for Gentiana genus.


2003 ◽  
Vol 50 (4) ◽  
pp. 129-133
Author(s):  
Srdjan Dikic ◽  
Dragoljub Bilanovic ◽  
Tomislav Randjelovic ◽  
D. Radovanovic ◽  
Miroslav Granic ◽  
...  

Diagnosis of intraabdominal bleeding caused by spleen injury must be performed in the shortest possible period of time, with little risk for the patient, and with high preciseness. By its simple performance, high preciseness and little risk for the patient, DPL imposes as the predominant method in initial diagnostic of intraabdominal bleeding. Control and monitoring of lavage may duly signalize degree of bleeding. Preciseness of this diagnostic in our series ranges up to 93.3%. DPL method is especially important in a combined neurotrauma. Ultrasonography is a sovereign method in diagnostic of bleeding source as well as in monitoring of bleeding that from the very beginning does not require urgent surgical intervention. Its importance is in monitoring both intrasplenic and subcapsulary hematomas. It is not appliable in disturbed and haemodynamically unstable patients. It is in particular important in children where a maximum conservative attitude with respect to operative treatment has been assumed. CT takes the leading place with respect to preciseness of bleeding area, and the combined thoracoabdominal trauma. Preciseness of CT in our series comes up to 96.6%, but can be applied only in haemodynamically stable patients. Same as US of abdomen so the CT of abdomen represents a prominent method in monitoring of both intrasplenic and subcapsular hematomas, which do not require urgent surgical intervention.


2017 ◽  
pp. 5
Author(s):  
Eduardo García-Villanueva ◽  
E. Mark Engleman

Seeds of several Yucca species have been studied by Arnott and Horner. They mainly studied the nature condition and stated that the extra-embryonic food reserve tissue is a perisperm. This paper provides ontogenic evidence that this tissue is an endosperm with nuclear development type. The seed shape is nearly a triangular prism less than 1 cm long, black color and the raphe groove is conspicuous. The seed coat is derived exclusively from the outer integument. The exotesta external periclinal cell wall appears with irregular thickness. Both mesotesta and endotesta grow irregularly inward the seed confering to the endosperm a ruminate appearance. Toward seed maturity, the inner integument tissues disappear, thus fusion between intertegumentary and tegmen-nucellar cuticles occurs; valuable ontogenic information is showed by the cuticles, due to its persistence in spite of its generative tissue disappearance. The embryo development increases until 10 weeks after anthesis, it is cylindric, folds like "S" and two thirds of its chalazal lenght correspond to the cotyledon.


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