GERMINATION AND MORPHOLOGY OF SEEDS AND SEEDLINGS OF Parkia gigantocarpa FABACEAE: MIMOSOIDEAE

AbstractParkia gigantocarpa is a valuable timber tree, and due to its rapid growth and great survival can be used to enrich forest clearings. The aims of this study was describe main morphological characters of seeds and seedlings, and to evaluate germination and initial growth of the species at six temperatures. The seed shape varies from elliptical, oblong or ovoid with bone consistency surface, smooth, glossy black color and presence of pleurogram. Average dimensions were 21.25 mm (length), 10.43 mm (width), and 6.15 mm (thickness). The embryo type is linear axial, with fleshy cotyledons, convex planes and dominant. The germination is epigeous phanerocotyledonary with fleshy cotyledons, and occurs between the second and fifth days after sowing. The fully developed seedling stage was reached on the fifteenth day after sowing. Temperatures of 30 and 35 C provided higher germination rates in less time and with higher root biomass allocation.Keywords: Amazon; biometrics; germination temperature; fava-atanã; forest seeds. ResumoGerminação e morfologia de sementes e plântulas de Parkia gigantocarpa Fabaceae: Mimosoidae. Parkia gigantocarpa é uma árvore de interesse madeireiro, indicada para o enriquecimento de clareiras devido seu rápido crescimento. Os objetivos deste trabalho foram descrever os principais caracteres morfológicos de sementes e plântulas, e avaliar a germinação de sementes e desenvolvimento inicial da espécie em seis temperaturas. As sementes apresentam formato que varia de elíptica, ovóide ou oblonga com superfície de consistência óssea, lisa, brilhosa de coloração negra e presença de pleurograma, com dimensões médias de 21,25 mm de comprimento, 10,43 mm de largura, e 6,15 mm de espessura. O embrião é do tipo axial linear, com cotilédones crassos, plano convexos e dominantes. A germinação é epígea fanerocotiledonar com cotilédones carnosos, e ocorre entre o segundo e quinto dias após semeadura, sendo que o estágio de plântula completamente formada é alcançado no décimo quinto dia após a semeadura. As temperaturas de 30 e 35 ºC proporcionaram elevadas taxas de germinação em menor tempo e com maior alocação de biomassa radicular.Palavras-chave: Amazônia; biometria; temperatura para germinação; fava-atanã; sementes florestais.

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Systematics, Biogeography, and Morphological Character Evolution of the Hemiepiphytic Subfamily Monsteroideae (Araceae)

Annals of the Missouri Botanical Garden ◽

10.3417/2018269 ◽

2019 ◽

Vol 104 (1) ◽

pp. 33-48 ◽

Cited By ~ 4

Author(s):

Alejandro Zuluaga ◽

Martin Llano ◽

Ken Cameron

Keyword(s):

Dna Sequences ◽

Pacific Islands ◽

R Package ◽

Morphological Characters ◽

Ancestral State ◽

Seed Shape ◽

Long Distance ◽

The Pacific ◽

And Migration ◽

The Tropics

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.

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Ontogenia de la semilla de Yucca periculosa (Agavaceae)

Botanical Sciences ◽

10.17129/botsci.1534 ◽

2017 ◽

pp. 5

Author(s):

Eduardo García-Villanueva ◽

E. Mark Engleman

Keyword(s):

Cell Wall ◽

Embryo Development ◽

Seed Coat ◽

Outer Integument ◽

Triangular Prism ◽

Seed Shape ◽

Food Reserve ◽

Seed Maturity ◽

Nuclear Development ◽

Black Color

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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A revision of the Rhododendron taipaoense complex (subg. Tsutsusi sect. Tsutsusi, Ericaceae), based on observations of morphological characters and seed micromorphology

Phytotaxa ◽

10.11646/phytotaxa.92.2.1 ◽

2013 ◽

Vol 92 (2) ◽

pp. 25

Author(s):

XIAO-FENG JIN ◽

BING-YANG DING ◽

YING-YING ZHOU ◽

SHUI-HU JIN ◽

WANG-WEI YANG

Keyword(s):

Morphological Characters ◽

Principal Coordinate Analysis ◽

Morphological Data ◽

Herbarium Specimens ◽

Leaf Color ◽

Flower Number ◽

Seed Shape ◽

Corolla Length ◽

Seed Micromorphology ◽

Different Populations

In this paper, we present a revision of the Rhododenron taipaoense complex, including R. taipaoense and eight other named species, based on literature survey, field collections and observations, inspection of herbarium specimens, statistical analysis of morphological characters, and SEM observation of seed shape and testa. We evaluated all characters that have previously been used to diagnose these species: indumentum of young shoots and abaxial surfaces of leaves; filament dimensions; style base; leaf color, size, and apex shape; flower number per inflorescence; corolla length; and length of the stamen and pistil. Cluster analysis of 146 individuals showed that individuals from different populations are interdigitated, irrespective of traditional taxonomic limits. Analysis of morphological data using principal coordinate analysis (PCoA) likewise shows a continual gradation between populations, rather than disjunctures between named species. Consequently, only one species is recognized in the present paper, and R. apricum, R. falcinellum (R. apricum var. falcinellum), R. florulentum, R. hepticum, R. piceum, R. rufulum, R. spadiceum, and R. rufoindumentum (nom. nud.) are all reduced to synonyms of R. taipaoense.

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Revision of Spergularia (Caryophyllaceae) in Australia

Australian Systematic Botany ◽

10.1071/sb08015 ◽

2008 ◽

Vol 21 (4) ◽

pp. 251

Author(s):

Laurie G. Adams ◽

Judy G. West ◽

Kirsten J. Cowley

Keyword(s):

Electron Micrographs ◽

Field Studies ◽

Morphological Characters ◽

Scanning Electron Micrographs ◽

Seed Shape ◽

Herbarium Material ◽

Diagnostic Characters ◽

Surface Features ◽

Scanning Electron ◽

Eleven Species

A revision of the Australian taxa of the genus Spergularia (Caryophyllaceae) on the basis of herbarium material, field studies and analysis of morphological characters necessitates realignment of some taxa and application of some neglected names, clarifying circumscription and understanding of the species of this genus. Eleven species are here recognised, with five considered indigenous, Spergularia nesophila and S. diandroides described as new and S. tasmanica transferred to Spergularia from Lepigonum. Fruits and seeds provide compelling diagnostic characters in this genus and are used in supplementary dichotomous and tabular diagnostic keys. Scanning electron micrographs (SEMs) illustrate key seed shape and surface features.

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The response of garden pea cultivars to simulated drought

Acta agriculturae Serbica ◽

10.5937/aaser2152167t ◽

2021 ◽

Vol 26 (52) ◽

pp. 167-173

Author(s):

Gordana Tamindžić ◽

Janko Červenski ◽

Dragana Milošević ◽

Slobodan Vlajić ◽

Zorica Nikolić ◽

...

Keyword(s):

Drought Stress ◽

Root Biomass ◽

Sensitivity Threshold ◽

Tolerance Index ◽

Severe Drought ◽

Initial Growth ◽

Garden Pea ◽

Randomized Design ◽

Drought Tolerance Index ◽

Shoot And Root Biomass

This study aimed to estimate genetic variability among four pea cultivars and determine seed physiological quality and initial growth of garden pea (Pisum sativum L.) under drought stress. Seeds of the pea cultivars were subjected to water stress induced by polyethylene glycol PEG 6000 at three stress levels (0; -0.15; -0.49, and -1.03 MPa). The experiment was conducted under laboratory conditions, in a completely randomized design with four replications, to estimate germination energy, germination, abnormal seedlings, fresh and dry shoot and root biomass, and drought tolerance index. Drought stress significantly affected germination and the other traits, with the stress effects being proportional to the stress level applied. Findings point to the fact that the osmotic potential of -0.49 MPa might be the germination sensitivity threshold for pea cultivars. The pea cultivar C1 was the most tolerant, having the highest germination, fresh and dry shoot and root biomass, and DTI under severe drought stress. Further research on the assessment of physiological and biochemical responses to drought stress is needed to confirm the findings of the present study.

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Taxonomic implications of seed morphology and storage proteins in three tribes of the subfamily Papilionoideae (Fabaceae) in Egypt

Phytotaxa ◽

10.11646/phytotaxa.484.1.3 ◽

2021 ◽

Vol 484 (1) ◽

pp. 75-95

Author(s):

MOSTAFA A. ABOULELA ◽

ZEINAB A. EL-KAREMY ◽

HASNAA A. HOSNI ◽

SARA M. SALEH ◽

AHMED M. FARIED

Keyword(s):

Multivariate Analyses ◽

Storage Proteins ◽

Seed Storage ◽

Seed Storage Proteins ◽

Morphological Characters ◽

Seed Morphology ◽

Seed Shape ◽

The Core ◽

Phylogenetic Implications ◽

And Storage

Papilionoideae is the most species-rich subfamily of Fabaceae. Within Papilionoideae, the “core genistoids” comprise many genera of the tribes Podalyrieae, Thermopsideae, Euchresteae, Crotalarieae, Genisteae, and part of Sophoreae. Seed macro- and micro-morphological characters and seed storage proteins of 12 Egyptian species belonging to three tribes of the core genistoides (Sophoreae, Crotalarieae, and Genisteae) were examined using light microscopy, scanning electron microscopy, and SDS-PAGE electrophoresis. Seed shape, size, surface topography, hilum characteristics, epidermal cell patterns, periclinal cell walls, and anticlinal cell boundaries are described here. Seed protein profiles show variable banding patterns with molecular weights ranging from approximately 5 to 270 kDa. Multivariate analyses based on seed morphology and storage proteins elucidate the phenetic relationships among the investigated species at both the tribal and intrageneric levels. The taxonomic and phylogenetic implications of multivariate analyses are compared with previous and current systematic treatments of the genera within the three tribes. Our results confirm the high taxonomic importance of seed morphology in distinguishing among the investigated species. A key to the species using seed macro- and micro-morphological characters is presented.

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Rapid growth of organic aerosol nanoparticles over a wide tropospheric temperature range

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1807604115 ◽

2018 ◽

Vol 115 (37) ◽

pp. 9122-9127 ◽

Cited By ~ 37

Author(s):

Dominik Stolzenburg ◽

Lukas Fischer ◽

Alexander L. Vogel ◽

Martin Heinritzi ◽

Meredith Schervish ◽

...

Keyword(s):

Growth Rates ◽

Rapid Growth ◽

Aerosol Particles ◽

Particle Growth ◽

Molecular Cluster ◽

Tropospheric Temperature ◽

Initial Growth ◽

European Organization ◽

Cold Temperatures ◽

Wide Range

Nucleation and growth of aerosol particles from atmospheric vapors constitutes a major source of global cloud condensation nuclei (CCN). The fraction of newly formed particles that reaches CCN sizes is highly sensitive to particle growth rates, especially for particle sizes <10 nm, where coagulation losses to larger aerosol particles are greatest. Recent results show that some oxidation products from biogenic volatile organic compounds are major contributors to particle formation and initial growth. However, whether oxidized organics contribute to particle growth over the broad span of tropospheric temperatures remains an open question, and quantitative mass balance for organic growth has yet to be demonstrated at any temperature. Here, in experiments performed under atmospheric conditions in the Cosmics Leaving Outdoor Droplets (CLOUD) chamber at the European Organization for Nuclear Research (CERN), we show that rapid growth of organic particles occurs over the range from −25 °C to 25 °C. The lower extent of autoxidation at reduced temperatures is compensated by the decreased volatility of all oxidized molecules. This is confirmed by particle-phase composition measurements, showing enhanced uptake of relatively less oxygenated products at cold temperatures. We can reproduce the measured growth rates using an aerosol growth model based entirely on the experimentally measured gas-phase spectra of oxidized organic molecules obtained from two complementary mass spectrometers. We show that the growth rates are sensitive to particle curvature, explaining widespread atmospheric observations that particle growth rates increase in the single-digit-nanometer size range. Our results demonstrate that organic vapors can contribute to particle growth over a wide range of tropospheric temperatures from molecular cluster sizes onward.

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Lachenalia arenicola (Asparagaceae: Scilloideae), a new species from western South Africa

Phytotaxa ◽

10.11646/phytotaxa.186.5.8 ◽

2014 ◽

Vol 186 (5) ◽

pp. 297 ◽

Cited By ~ 1

Author(s):

GRAHAM DUNCAN ◽

NICK A. HELME

Keyword(s):

South Africa ◽

New Species ◽

Summer Rainfall ◽

Morphological Characters ◽

Phylogenetic Study ◽

Seed Shape ◽

Tube Shape ◽

Perianth Tube ◽

Living Material ◽

A New Species

Lachenalia Jacquin in Murray (1784: 314) is a deciduous, geophytic genus endemic to western, southern, southeastern and central South Africa and to western and southern Namibia (Duncan et al. 2005). All South African members produce leaves in the winter, including those from essentially summer-rainfall areas, and L. pearsonii (Glover 1915: 105) Barker (1969: 321) from southern Namibia is the only summer-growing species (Duncan & Condy 2013). Flower and seed characters are most important for identification of Lachenalia, especially perianth shape including the perianth tube shape and length, relative position of outer and inner tepals, stamen orientation, seed shape and strophiole length. A recent monograph of Lachenalia provided a new classification for the genus based on a phylogenetic study of morphological characters and recognized 133 species (Duncan 2012). Living material of a new species from the Namaqualand coastal plain became available for study in 2013, although pressed specimens were first gathered in 2006. The total number of species for the genus now stands at 134.

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Competition and growth of a grass–legume mixture fertilised with nitrogen and phosphorus: effect on nutrient acquisition, root morphology and symbiosis with soil microorganisms

Crop and Pasture Science ◽

10.1071/cp15257 ◽

2016 ◽

Vol 67 (6) ◽

pp. 629 ◽

Cited By ~ 6

Author(s):

Rodolfo Mendoza ◽

Ileana García ◽

Daniela Deplama ◽

Carolina Fernández López

Keyword(s):

Surface Area ◽

Root Length ◽

Root Biomass ◽

Root Surface ◽

Shoot Biomass ◽

Root Surface Area ◽

N Fixation ◽

Initial Growth ◽

Mixed Stands ◽

Mycorrhizal Colonisation

Achieving a fast initial growth is crucial for legumes because grasses grow more rapidly and compete much better with forbs. In a pot experiment with a nutrient-deficient soil, we added nitrogen (N), phosphorus (P) and N + P to pure and mixed stands of Lotus tenuis and Festuca arundinacea and investigated the effects of on plant growth, nutrient uptake and symbiotic associations with arbuscular mycorrhizae and rhizobia. Plant yield, N and P acquisition, mycorrhizal colonisation, rhizobial nodulation and root length were measured and root diameter and root surface area were calculated after two harvests. Species responded differently to specific nutrients when grown pure or mixed. Comparing pure with mixed stands in soils fertilised with P and N + P, L. tenuis showed decreased shoot and particularly root biomass, whereas F. arundinacea showed increases in both biomasses. This suggests that the competitiveness of the grass with the legume increased upon P and N + P addition. In mixed stands, F. arundinacea produced 51–64% of the total shoot biomass and 69–74% of the total root biomass with P and N + P, respectively. Root length and root surface area were greater and the roots thinner in F. arundinacea than in L. tenuis. Addition of P and N + P increased rhizobial nodulation in legume roots but decreased mycorrhizal colonisation in both plants. Supply of N does not necessarily favour grasses, whereas P supply favours legumes. Optimisation of P nutrition might help to maximise N inputs into grasslands by symbiotic N-fixation and decrease inputs of inorganic N by fertilisation.

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Seed Morphology in Key Spanish Grapevine Cultivars

Agronomy ◽

10.3390/agronomy11040734 ◽

2021 ◽

Vol 11 (4) ◽

pp. 734

Author(s):

Emilio Cervantes ◽

José Javier Martín-Gómez ◽

Francisco Emmanuel Espinosa-Roldán ◽

Gregorio Muñoz-Organero ◽

Ángel Tocino ◽

...

Keyword(s):

Image Analysis ◽

Morphological Characters ◽

Seed Morphology ◽

Dna Polymorphisms ◽

Seed Shape ◽

Geometric Figure ◽

Geometric Figures ◽

New Methods ◽

New Models

Ampelography, the botanical discipline dedicated to the identification and classification of grapevine cultivars, was grounded on the description of morphological characters and more recently is based on the application of DNA polymorphisms. New methods of image analysis may help to optimize morphological approaches in ampelography. The objective of this study was the classification of representative cultivars of Vitis vinifera conserved in the Spanish collection of IMIDRA according to seed shape. Thirty eight cultivars representing the diversity of this collection were analyzed. A consensus seed silhouette was defined for each cultivar representing the geometric figure that better adjusted to their seed shape. All the cultivars tested were classified in ten morphological groups, each corresponding to a new model. The models are geometric figures defined by equations and similarity to each model is evaluated by quantification of percent of the area shared by the two figures, the seed and the model (J index). The comparison of seed images with geometric models is a rapid and convenient method to classify cultivars. A large proportion of the collection may be classified according to the new models described and the method permits to find new models according to seed shape in other cultivars.

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