Obtaining spores for the production of Saccharina latissima: seasonal limitations in nature, and induction of sporogenesis in darkness

AbstractWhen cultivating the kelp Saccharina latissima, knowledge on the availability of seeding material for the production is essential. Applying a spore seeding approach requires spores from the reproductive organs of the fertile sporophytes (sori). As sori are generally not present during the time of seeding in late summer, the production of spores (sporogenesis) can be artificially induced by removing the meristematic part of the sporophyte and keeping the sporophyte under short day, temperate, and nutrient-replete conditions. Only limited information is available on the effect of light intensities including darkness on the sporogenesis of S. latissima. This study examined the natural pattern of sporogenesis in S. latissima from Middelfart, Denmark, and the effect of four different light regimes (0, 20, 60, or 120 μmol photons m−2 s−1) on the artificial induction of sporogenesis in S. latissima. Natural reproductivity and availability of spores in Denmark peaked in early winter, with 86% of the population being reproductive in November. Reproductive material was available from October until late spring, but with a variable spore release from 11 × 103 to 1.2 × 106 spores cm−2 sori. The artificial induction of sporogenesis was optimal in darkness with > 90% of sporophytes developing sori after 49 days, with an average spore release density of 1.15 ± 0.38 × 106 spores cm−2 sori. The results confirmed that S. latissima in Denmark follows the general pattern of reproduction of S. latissima in North Atlantic regions and demonstrated for the first time that sporogenesis in S. latissima can be efficiently induced in darkness.

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Spatial and temporal distribution of phytoplankton in Lake Skadar

Archives of Biological Sciences ◽

10.2298/abs1202585r ◽

2012 ◽

Vol 64 (2) ◽

pp. 585-595 ◽

Cited By ~ 3

Author(s):

Jelena Rakocevic

Keyword(s):

Spatial Heterogeneity ◽

Phytoplankton Community ◽

General Pattern ◽

Seasonal Succession ◽

Temporal Distribution ◽

Late Summer ◽

Early Summer ◽

Quantitative Composition ◽

Autumn And Winter ◽

Lake Skadar

Phytoplankton seasonal succession and spatial heterogeneity were studied in Lake Skadar from February to December 2004. A total of 167 taxa from 6 algal divisions were observed, with Bacillariophyta being best represented (52.8%). The general pattern of phytoplankton seasonal succession in Lake Skadar was: Bacillariophyta in the spring, Chlorophyta in early summer, Cyanobacteria and Chlorophyta in late summer and Bacillariophyta and Chlorophyta in autumn and winter. Distinct spatial heterogeneity was observed. The central, open part of the lake (pelagic zone) was characterized by dominant euplanktonic species, mostly diatoms, whereas the western and northwestern parts (more isolated and shallower) had higher abundance of greens and blue-greens and a higher percentage of resuspended benthic-epiphytic forms in the phytoplankton community. Comparison with former phytoplankton data showed distinct differences in terms of the qualitative and quantitative composition of the phytoplankton community of Lake Skadar, which indicates lake deterioration.

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A biodiversity hotspot for Microgastrinae (Hymenoptera, Braconidae) in North America: annotated species checklist for Ottawa, Canada

ZooKeys ◽

10.3897/zookeys.63.10480 ◽

2016 ◽

Vol 633 ◽

pp. 1-93 ◽

Cited By ~ 1

Author(s):

Jose Fernandez-Triana ◽

Caroline Boudreault ◽

Joel Buffam ◽

Ronald Maclean

Keyword(s):

North America ◽

General Pattern ◽

Late Summer ◽

The United States ◽

Early Summer ◽

Individual Species ◽

Early Fall ◽

Two Peaks ◽

Annotated Checklist ◽

First Time

Microgastrinae wasps (Hymenoptera, Braconidae) from the city of Ottawa and its surroundings (a 50-km radius circle, ~7,800 km2) were studied based on 1,928 specimens collected between 1894 and 2010, and housed in the Canadian National Collection of Insects. A total of 158 species from 21 genera were identified, which is by far the highest number of species ever recorded for a locality in North America. An annotated checklist of species is provided.Choerasparasitellae(Bouché, 1834) andPholetesornanus(Reinhard, 1880) are recorded for the first time in the Nearctic (previously only known from the Palearctic region),Cotesiadepressa(Viereck, 1912) is recorded for the first time in Canada (previously only known from the United States), andCotesiahemileucae(Riley, 1881) andProtapantelesphlyctaeniae(Muesebeck, 1929) are recorded for the first time in the province of Ontario. In Ottawa the most diverse genera areCotesia,Apanteles,Microplitis,Pholetesor,Microgaster, andDolichogenidea, altogether comprising 77% of the species found in the area. A total of 73 species (46%) were represented by only one or two specimens, suggesting that the inventory for Ottawa is still relatively incomplete. Seasonal distribution showed several peaks of activity, in spring, summer, and early fall. That general pattern varied for individual species, with some showing a single peak of abundance either in the summer or towards the end of the season, others species attaining two peaks, in late spring and late summer, or in early summer and early fall, and yet others attaining up to three different peaks, in spring, summer and fall. At least 72 of the Microgastrinae species from Ottawa have been previously associated with 554 species of Lepidoptera as hosts – but those historical literature records are not always reliable and in many cases are based on data from areas beyond Ottawa. Thus, our knowledge of the associations between the 158 species of microgastrine parasitoids and the caterpillars of the 2,064 species of Lepidoptera recorded from Ottawa is still very incomplete.

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Return migration patterns of porbeagle shark (Lamna nasus) in the Northeast Atlantic: implications for stock range and structure

ICES Journal of Marine Science ◽

10.1093/icesjms/fsw233 ◽

2017 ◽

Vol 74 (5) ◽

pp. 1268-1276 ◽

Cited By ~ 10

Author(s):

Gérard Biais ◽

Yann Coupeau ◽

Bernard Séret ◽

Beatriz Calmettes ◽

Rémy Lopez ◽

...

Keyword(s):

General Pattern ◽

Late Summer ◽

The Arctic ◽

Bay Of Biscay ◽

Migration Patterns ◽

Northeast Atlantic ◽

Archival Tags ◽

Mid Atlantic Ridge ◽

The Common ◽

The Mean

During two surveys in 2011 and 2013, we deployed pop-up satellite archival tags (PSATs) on subadult or adult porbeagles at the Bay of Biscay shelf break. We collected data that enabled the reconstruction of nine migrations (eight females, one male) that uncover the large spatial extent of these sharks in the Northeast Atlantic. The mean duration of each deployment was 292 d, with four reaching 365 d. The reconstructions show that, after migrations that extended up to 2000 km away from the point of release, the tagged porbeagles returned to their location of tagging. All the reconstructed migrations followed the same general pattern of a migration away from the Bay of Biscay in late summer, and a return in spring the following year. The total distance of the migrations was estimated at 5000–13 000 km for PSATs deployed for a full year (n = 4), with examples of migration to the Arctic Circle, southward to Madeira and westward to the mid-Atlantic Ridge. The observed site fidelity to the Bay of Biscay and the common migration pattern of all females provide evidence of complex spatial structure and dynamics that encompasses both the open ocean and heavily fished coastal areas, and highlights the challenge of assessing and managing the porbeagle stock in this area.

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Structurally preserved fungi from Antarctica: diversity and interactions in late Palaeozoic and Mesozoic polar forest ecosystems

Antarctic Science ◽

10.1017/s0954102016000018 ◽

2016 ◽

Vol 28 (3) ◽

pp. 153-173 ◽

Cited By ~ 21

Author(s):

Carla J. Harper ◽

Thomas N. Taylor ◽

Michael Krings ◽

Edith L. Taylor

Keyword(s):

Forest Ecosystems ◽

Research Effort ◽

Reproductive Organs ◽

Systematic Position ◽

Saprotrophic Fungi ◽

Light Regimes ◽

The Past ◽

Late Palaeozoic ◽

Fungal Associations ◽

Fungal Interactions

AbstractChert and silicified wood from the Permian through Cretaceous of Antarctica contain abundant information on fungal diversity and plant–fungal interactions. The chert deposits represent a particularly interesting setting for the study of plant–fungal interactions because they preserve remains of distinctive high latitude forest ecosystems with polar light regimes that underwent a profound climate change from icehouse to greenhouse conditions. Moreover, some of the cherts and wood show the predominance of extinct groups of seed plants (e.g. Glossopteridales, Corystospermales). Over the past 30 years, documentation of fossil fungi from Antarctica has shifted from a by-product of plant descriptive studies to a focused research effort. This paper critically reviews the published record of fungi and fungal associations and interactions in the late Palaeozoic and Mesozoic cherts and silicified wood from Antarctica; certain fungal palynomorphs and fungal remains associated with adpression fossils and cuticles are also considered. Evidence of mutualistic (mycorrhizal), parasitic and saprotrophic fungi associated with plant roots, stems, leaves and reproductive organs is presented, together with fungi occurring within the peat matrix and animal–fungus interactions. Special attention is paid to the morphology of the fungi, their systematic position and features that can be used to infer fungal nutritional modes.

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Seasonal changes in the germination responses of seeds of Veronica peregrina during burial, and ecological implications

Canadian Journal of Botany ◽

10.1139/b83-374 ◽

1983 ◽

Vol 61 (12) ◽

pp. 3332-3336 ◽

Cited By ~ 8

Author(s):

Jerry M. Baskin ◽

Carol C. Baskin

Keyword(s):

Seasonal Changes ◽

Natural Habitat ◽

General Pattern ◽

Late Summer ◽

Early Spring ◽

Late Winter ◽

Seasonal Temperature ◽

Light In August ◽

Late Autumn ◽

Response To Temperature

Seeds of Veronica peregrina collected from a field population in central Kentucky were buried in soil and exposed to seasonal temperature changes. Fresh seeds and those exhumed after 1–26 months were tested in light and darkness at five thermoperiods simulating those in the natural habitat from early spring through late autumn. Freshly matured seeds were dormant, but they came out of dormancy in June and July and germinated to 98–100% in light in August at thermoperiods of 20:10, 25:15, 30:15, and 35:20 °C. Seeds retained the ability to germinate to high percentages at these temperatures until late winter and spring, but they never germinated to high percentages in darkness. Thus, in the natural habitat in July and August germination is prevented only by darkness and (or) insufficient soil moisture. At simulated habitat temperatures, seeds germinated to 88–100% in March and April but to only 21–69% in May and June. Seeds incubated at 15:6 °C showed a decline in germination percentages in late summer and autumn and an increase during late autumn and winter. The same general pattern of seasonal changes in germination response to temperature occurred during the 2nd year of burial.

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Offspring Development Conditioning (ODC): A Universal Trend in Evolution of Higher Organisms’ Reproduction

10.21203/rs.3.rs-36696/v1 ◽

2020 ◽

Author(s):

Qiang Fu ◽

Jianni Liu ◽

Xin Wang

Keyword(s):

General Pattern ◽

Reproductive Organs ◽

Origin And Evolution ◽

The Public ◽

Offspring Development ◽

Reproductive Modes ◽

Reproductive Evolution

Abstract All organisms evolve, according to Darwin. The question is how? Is there any general pattern or trend in the organisms’ evolution? These are rarely asked – and almost never answered – questions. This situation makes the evolution frustrating and mysterious to many. Here, after surveying the reproductive modes in most animals and plants, we propose that all (at least most) of higher organisms demonstrate the similar trend underlying their reproductive evolution, namely, Offspring Development Conditioning (ODC). Such a pattern makes the origin and evolution of reproductive organs in both animals and plants rational and understandable. To the best of our knowledge, this pattern appears universal, although we encourage future authors to identify exceptions. We hope this will help frame the evolution of higher animals and plants, and make the latter understandable to the public.

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Myxobolus cerebralis (Myxozoa), the causative agent of whirling disease, reduces fecundity and feeding activity of Tubifex tubifex (Oligochaeta)

Parasitology ◽

10.1017/s0031182009005721 ◽

2009 ◽

Vol 136 (6) ◽

pp. 603-613 ◽

Cited By ~ 20

Author(s):

S. SHIRAKASHI ◽

M. EL-MATBOULI

Keyword(s):

Causative Agent ◽

Feeding Activity ◽

Ecological Impacts ◽

Tubifex Tubifex ◽

Infection Prevalence ◽

Limited Information ◽

Whirling Disease ◽

Myxobolus Cerebralis ◽

Cocoon Production ◽

Spore Release

SUMMARYMyxobolus cerebralis is the causative agent of whirling disease that has significant economical and ecological impacts on trout populations. Although intensive studies have been conducted to understand its effects on and interactions with its fish host, only limited information is available about how and to what extent M. cerebralis affects its oligochaete host, Tubifex tubifex. We investigated the effects of M. cerebralis on survival, growth, reproduction, and feeding activity of T. tubifex. Mature, immature and juvenile worms were exposed to myxospores and their infection prevalence, mortality, sexual development, reproduction and spore production were compared with unexposed worms. The parasite affected neither survival nor growth but inhibited clitellar development and reduced cocoon production by over 80%. Numbers of actinospores released from mature worms were nearly 9-fold higher than that of immature worms. When non-clitellated infected worms were kept at 30°C for 4 days, spore release ceased and they re-developed a clitellum. These results suggest parasite-induced castration. Comparative monitoring of defecation rate revealed that M. cerebralis reduced feeding activity of T. tubifex by approximately 40%. Low energy intake and impaired energetic allocation may be the underlying mechanism behind reduced fecundity of infected T. tubifex.

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KESIAPAN ANAK DAN PERAN ORANG TUA MUSLIM DALAM MEMPERSIAPKAN MENARCHE

Care Jurnal Ilmiah Ilmu Kesehatan ◽

10.33366/jc.v8i2.1462 ◽

2020 ◽

Vol 8 (2) ◽

pp. 284

Author(s):

Nur Maharani ◽

Restuning Widiasih ◽

Fanny Adistie

Keyword(s):

Family Support ◽

Muslim Women ◽

Sampling Technique ◽

Reproductive Organs ◽

Physiological Process ◽

Limited Information ◽

Purposive Sampling ◽

Descriptive Approach ◽

Quantitative Descriptive

Menarche a physiological process in puberty as a sign of the maturity in women’s reproductive organs. For Muslim women, a menarche is also an important event, because it signifies that a woman becomes 'baligh' (adult). Previous research shows that girls feel scared and unprepared when menarche, and limited information about family support for children. The purpose of this study was to examine the readiness of children and the roles of Muslim parents in dealing with menarche. This study applied a quantitative descriptive approach, the samples were selected using the purposive sampling technique, 176 students and parents from SDIT Imam Bukhari school involved in this study. The instrument was a questionnaire that assesses children's readiness and parents’ roles in assisting menarche. Data were analyzed using a frequency distribution.More than half of girls have good readiness (54.5%), and other children in the category moderate or poor. Parents as educators have a good role in preparing girls (52.3%) in component needs, motives, and goals. Most children are ready in dealing with menarche and getting support from parents. Providing menarche information at school would help children readiness especially who are in categories moderate and poor.

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SOME EFFECTS OF GONADOTROPIC HORMONES ON THE THREESPINE STICKLEBACK, GASTEROSTEUS ACULEATUS

Canadian Journal of Zoology ◽

10.1139/z63-081 ◽

1963 ◽

Vol 41 (6) ◽

pp. 1045-1053 ◽

Cited By ~ 34

Author(s):

S. Nazar Ahsan ◽

William S. Hoar

Keyword(s):

Gasterosteus Aculeatus ◽

Late Summer ◽

Reproductive Organs ◽

Threespine Stickleback ◽

Late Winter ◽

Condition Characteristic ◽

Mature Fish ◽

Sexually Mature ◽

Gonadotropic Hormones ◽

Stimulation Of

Sticklebacks collected during the autumn and maintained under 8-hour daily photoperiods did not mature sexually; their gonads remained in the condition characteristic of late summer and autumn fish in nature and probably did not change after the fish were placed under controlled photoperiods. No stimulation of the gametogenetic and related tissues occurred when these fish were treated with purified mammalian FSH (Armour) but LH (Armour) produced a maturation of all gonads to stages characteristic of late winter and spring fish; with LH, 80% of the individuals attained the stages of sexually mature fish in nature. Chorionic gonadotropins (Organon) also had a stimulatory effect but were considerably less active than the LH; PMS was more effective than HCG. TSH (Parke Davis or Organon) had a marked gonadotropic action as well as the expected thyrotropic effect and stimulated the reproductive organs to about the same degree as the chorionic gonadotropins. Crude extracts of alcohol-preserved salmon pituitaries were only mildly active but stimulated all gonads to stages beyond those normally found in the late summer and autumn.

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Ömer Besçeli: an unnoticed researcher in the history of pine processionary moth pupation research

Entomologist s Gazette ◽

10.31184/g00138894.712.1758 ◽

2020 ◽

Vol 71 (2) ◽

pp. 125-129

Author(s):

Kahraman İpekdal ◽

Mustafa Avci

Keyword(s):

General Pattern ◽

Late Summer ◽

Thaumetopoea Pityocampa ◽

Pine Processionary Moth ◽

Processionary Moth ◽

Thaumetopoea Wilkinsoni ◽

Long Time ◽

History Of ◽

Continuous Support ◽

Prolonged Diapause

Pine processionary moths, Thaumetopoea wilkinsoni Tams, 1924 and Thaumetopoea pityocampa ([Denis & Schiffermüller], 1775) (Lepidoptera: Notodontidae) are among the most destructive pine pests in Mediterranean basin. Their larvae descend to the ground from the canopy in spring for pupation and rest there until late summer. Although this is the general pattern, pupal period is a plastic feature and can be prolonged for up to several years. It is considered one of several difficulties of processionary moth management as such a plasticity provides a continuous support from the underground reservoir to the pest population. This phenomenon has been known for a long time and its discovery has been attributed to Guy Démolin; renowned INRA (France) researcher. Here, we report an unnoticed researcher, Ömer Besçeli, from Turkey who published the phenomenon of prolonged diapause in the pine processionary moth earlier.

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