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As one of the most important crops in the world, rice (Oryza sativa) is a model plant for metabolome research. Although many studies have focused on the analysis of specific tissues, the changes in metabolite abundance across the entire life cycle have not yet been determined. In this study, combining both targeted and nontargeted metabolite profiling methods, a total of 825 annotated metabolites were quantified in rice samples from different tissues covering the entire life cycle. The contents of metabolites in different tissues of rice were significantly different, with various metabolites accumulating in the plumule and radicle during seed germination. Combining these data with transcriptome data obtained from the same time period, we constructed the Rice Metabolic Regulation Network. The metabolites and co-expressed genes were further divided into 12 clusters according to their accumulation patterns, with members within each cluster displaying a uniform and clear pattern of abundance across development. Using this dataset, we established a comprehensive metabolic profile of the rice life cycle and used two independent strategies to identify novel transcription factors—namely the use of known regulatory genes as bait to screen for new networks underlying lignin metabolism and the unbiased identification of new glycerophospholipid metabolism regulators on the basis of tissue specificity. This study thus demonstrates how guilt-by-association analysis of metabolome and transcriptome data spanning the entire life cycle in cereal crops provides novel resources and tools to aid in understanding the mechanisms underlying important agronomic traits.

Understanding the role different habitats play in the life histories of fishes is important for the development of holistic aquatic ecosystem management plans. We used otolith trace element analysis to reconstruct the life history of estuarine triplefin Forsterygion nigripenne and infer its habitat use. Analysis of otoliths using laser ablation inductively coupled plasma mass spectrometry showed an elemental profile without prominent changes in elemental concentration. The otolith elemental profiles were not indicative of movement between waters with substantial Sr:Ca and Ba:Ca differences. The Sr:Ca and Ba:Ca profiles were indicative of within—and near—estuary movements encompassing short time periods. Overall, the otolith microchemical profile was likely indicative of a life history closely associated with estuaries. However, it is difficult to rule out brief excursions to the marine environment given that may not have been of sufficient duration to be recorded in the elemental composition of the otolith. This suggests that F. nigripenne is the only species in southern New Zealand known to be closely associated with estuarine habitat for its entire life cycle.

Waste heaps of Atta are host to an extraordinary diversity of myrmecophiles insects and other arthropods. In this study, the presence of four species of pseudoscorpions is recorded in two Atta colombica waste heaps in the years 2016 and 2017. Two of these species, Cordylochernes scorpioides and Lustrochernes carolinensis are new records in waste heaps and except for the deutonymphs of L.carolinensis, the others all stages of post-embryonic development were present in the studied heaps, which could indicate that these two species carry out their entire life cycle in these waste mounds and live there permanently.

Orchids are highly dependent on symbiotic microorganisms during their entire life cycle. Whereas an important role in orchid seed germination and early plant development is well established for mycorrhizal fungi, the influence of endophytic bacteria on orchid growth has been less investigated. Here, we report the isolation of endophytic bacteria from different organs of three terrestrial Mediterranean orchid species (Spiranthes spiralis, Serapias vomeracea and Neottia ovata), the investigation of their potential Plant Growth-Promoting (PGP) traits and their interaction with the orchid mycorrhizal (OM) fungus Tulasnella calospora in vitro. Little overlap was found among endophytic bacteria isolated from the different organs of the three orchid species. Taxonomic identification, based on the 16S rRNA gene, of fifty dereplicated bacterial isolates revealed that they belong to the genera Pseudomonas, Pantoea, Rahnella, Staphylococcus, Sphingomonas, Microbacterium, Streptomyces, Fictibacillus and Bacillus. Most bacterial isolates exhibited some potential PGP traits, such as nutrient solubilization, ACC deaminase activities and/or IAA biosynthesis. Although some Pseudomonas reduced growth of the OM fungus Tulasnella calospora, most isolates did not affect fungal growth. These results increase our understanding of the diversity and potential PGP functions of bacterial endophytes in terrestrial orchids, and suggest a role as beneficial partners in the orchid microbiota.

Trait covariation during multiphasic growth is of crucial significance to optimal survival and reproduction during the entire life cycle. However, current analyses are mainly focused on the study of individual traits, but exploring how genes determine trait interdependence spanning multiphasic growth processes remains challenging. In this study, we constructed a nonlinear mixed mapping framework to explore the genetic mechanisms that regulate multiphasic growth changes between two complex traits and used this framework to study stem diameter and stem height in forest trees. The multiphasic nonlinear mixed mapping framework was implemented in system mapping, by which several key quantitative trait loci were found to interpret the process and pattern of stem wood growth by regulating the ecological interactions of stem apical and lateral growth. We quantified the timing and pattern of the vegetative phase transition between independently regulated, temporally coordinated processes. Furthermore, we visualized the genetic machinery of significant loci, including genetic effects, genetic contribution analysis, and the regulatory relationship between these markers in the network structure. We validated the utility of the new mapping framework experimentally via computer simulations. The results may improve our understanding of the evolution of development in changing environments.

In this study, trees in production and saplings of Chinese main bayberry cultivars ‘Dongkui’ (Myrica rubra Sieb.&Zucc.) and ‘Biqi’ (Myrica rubra) were used to investigate the relationships of the different dosages and methods of 15% paclobutrazol (PP333) application and the incidence of twig dieback. The results showed that higher concentration of PP333 application caused greater PP333 residues in the plant body, and the residue of PP333 was positively correlated with the incidence of twig dieback, which means greater PP333 residues in the plant body leads to higher incidence of twig dieback. Moreover, the content of PP333 residues in the plant body after soil application was more than that after foliar spraying. The detection of pathogens in field plants showed that in addition to the two pathogens Pestalotiopsis mangiferae and P. vismiae, the presence of pathogen P. versicolor was found among different bayberry cultivars. The incidence of twig dieback of ‘Dongkui’ cultivar and ‘Biqi’ cultivar were ranked in the first two of all bayberry varieties, and the incidence of this disease in the ‘Dongkui’ cultivar was higher than ‘Biqi’ cultivar. The results of investigations conducted in 5 key provinces and 22 key counties suggested that low concentration of PP333 used as a plant growth inhibitor with 1 or 2 times intermittently throughout the entire life cycle was feasible to regulate the growth of Chinese bayberry. However, continuous excessive application could lead to extreme discordance between reproductive and vegetative growth and severely inhibit conducting tissues and tree vigor. In addition, the shrinking leaves and dead branches may increase sharply, promoting the infection and transmission of Pestalotiopsis spp.

Theory predicts that less fit individuals would disperse more often than fitter ones (Fitness Associated Dispersal, FAD hypothesis). To test this prediction under laboratory conditions, an entire life cycle of Lamium amplexicaule plants and the preferences of its dispersal agent, Messor ebeninus ants, were tracked. Characterization of individual L. amplexicaule plant revealed high variability in spot cover on the surface of the seeds, where less fit plants produce “unspotted seeds” (see Fig. 1 in Introduction). Unspotted L. amplexicaule seeds showed higher variation in germination time and lower germination rate. Moreover, M. ebeninus ants preferably collected these unspotted seeds. Our results show that low fitness L. amplexicaule plants produce seeds with higher potential for dispersal, supporting the FAD hypothesis in a plant-animal system.

Circular RNAs (circRNAs), an emerging class of non-coding RNAs, are abundant in eukaryotic transcriptomes. Seed germination is one of the most important stages in the entire life cycle of plants that can be slowed down or totally restrained by high temperature. Our aim is to identify heat-responsive circRNAs and explore the potential function of circRNAs in tomato seeds at high temperature. Following high-throughput sequencing, 4 164 circRNAs were identified, and 980 circRNAs were shared in the control and high-temperature libraries. Among the 748 circRNAs with high expressions, 73 circRNAs were significantly up-/down- regulated in tomato seeds germinated at high temperature compared to the control. The parental genes of circRNAs existing in seeds only at high temperature were mainly involved in metabolic processes, cellular processes, catalytic activities, and binding based on Gene Ontology analysis. The results suggested that circRNAs were widespread in tomato and were generated from different chromosomes and diverse genomic regions. Some circRNAs in tomato seeds responded to high temperature during germination. This study provides the first genome-wide profile of circRNAs in response to high temperature during tomato seed germination and lays a foundation for studying the potential biological functions of circRNAs responding to heat stress.

Plants face biotic and abiotic stresses during their entire life cycle, which leads to the loss in crop productivity. It has been shown that a relatively shorter exposure to heat stress, called priming, results in better adaptation of plants under subsequent stresses, which plants may face. While rice plants in nature often encounter high temperature stress conditions, the strategies to cope with those are poorly understood. We identified the involvement of microRNA pathways in the adaptation to heat stress (HS) at the physiological and molecular levels. It was observed that osa-miR169 levels are altered after HS and in response to light conditions. Its expression was also regulated by heat priming during anthesis and effectively responds to the successive exposure to high temperature stress during grain filling in rice. Osa-miR169 targets nuclear factor Y (NF-Y). We propose that osa-miR169: NF-Y regulatory module may be important for HS memory induced during high temperature priming and thus may serve to integrate stress responses with light regulated development. The future study in this direction will be useful to understand how plants acclimatize to the changing environment and thus help in generating stress tolerant crops.

Soybean (Glycine max), a typical short‐day plant (SDP) domesticated in temperate regions, has expanded to high latitudes where daylengths are long from soybean emergence to bloom, but rapidly decrease from seed filling to maturity. Cotyledons are well known as the major storage organs in seeds, but it is unclear whether developing cotyledons store flowering substances at filling stage in SD for upcoming seedlings, or instead respond to photoperiod for floral induction after emergence of matured seeds in long‐day (LD). Here, we report that cotyledons accelerate flowering of early‐maturing varieties not resulting from stored floral stimuli but by perceiving photoperiod after emergence. We found that light signal is indispensable to activate cotyledons for floral induction, and flowering promoting gene GmFT2a is required for cotyledon‐dependent floral induction via upregulation of floral identity gene GmAP1. Interestingly, cotyledons are competent to support the entire life cycle of a cotyledon‐only plant to produce seeds, underlying a new photoperiod study system in soybean and other dicots. Taken together, these results demonstrate a substantial role for cotyledons in flowering process, whereby we propose a ‘cotyledon‐based self‐reliance’ model highlighting floral induction from emergence as a key ecological adaptation for rapid flowering of SDPs grown in LD environments at high latitudes., The cotyledons induce soybean flowering by expressing flowering promoting gene GmFT2a after perceiving light signals at seedling stage. The cotyledon‐dependent floral induction accelerates the flowering of early‐maturing varieties in long‐day and facilitate them adapting to high latitudes.

10 pages, 6 figures, 5 tables, supplementary material https://doi.org/10.3989/scimar.05106.007, [EN] The age and growth patterns of the mesopelagic fish Ceratoscopelus maderensis (family Myctophidae) of the western Mediterranean Sea were described throughout its entire life cycle (from larvae to adult stages) using the sagittae otoliths of 59 individuals collected in December 2009. Three characteristic zones were identified along the cross-section of the sagittae (larval, metamorphic and juvenile-adult zones). Assuming growth rings as daily increments, the age of the analysed individuals (from 3.5 to 64 mm standard length [SL]) would range from 7 to 332 days. The relationship between the number of increments and the fish SL was fitted to a von Bertalanffy growth model (SL=70.5899×(1–exp(–0.0501(t+2.6705))). The growth pattern of C. maderensis in the western Mediterranean Sea was similar to that reported for this species in the northeast Atlantic Ocean. Though from a body size of 40-45 mm SL, growth rates declined more slowly in individuals from the western Mediterranean Sea, growth differences between these individuals and those from the northeast Atlantic Ocean were not statistically significant. This study provides new insights into the age and growth patterns of one of the most abundant mesopelagic fish species in the Mediterranean Sea that have clear implications for the study and management of marine ecosystems, [ES] En el presente trabajo se describen la edad y los patrones de crecimiento desde la fase larvaria hasta la fase adulta del pez mesopelágico Ceratoscopelus maderensis (familia Myctophidae) del Mediterráneo occidental. Para ello, se analizó el otolito sagitta de 59 individuos capturados en diciembre de 2009. Se identificaron tres zonas en la sagitta, cada una de las cuales se corresponde con una fase del desarrollo ontogenético del pez: larvaria, metamórfica y juvenil-adulta. Asumiendo que los anillos de crecimiento son diarios, la edad de los individuos analizados (de 3.5 a 64 mm de longitud estándar [SL]) oscilaría entre 7 y 332 días. La relación entre el número de incrementos y la SL de los peces se ajustó al modelo de crecimiento de von Bertalanffy (SL=70.5899×(1–exp(–0.0501(t+2.6705))). El patrón de crecimiento de C. maderensisen el Mediterráneo occidental fue similar al previamente descrito para esta especie en el Noreste del Océano Atlántico. A pesar de que, a partir de 40-45 mm SL, las tasas de crecimiento disminuyeron más lentamente en los individuos del Medi-terráneo occidental, las diferencias de crecimiento entre estos individuos y los del Noreste del Océano Atlántico no fueron estadísticamente significativas. Los resultados de este estudio aportan nuevos conocimientos sobre la edad y el crecimiento de una de las especies más abundantes del Mar Mediterráneo, lo cual tiene claras implicaciones de cara al estudio y la gestión de los ecosistemas marinos, The authors are very grateful to the IDEADOS project (CTM2008-04489-C03-02) and for the technical sup-port offered by José Manuel Fortuño (ICM) and Silvia Pérez-Mayol of the Sclerochronology Service at IME-DEA (UIB-CSIC), With the funding support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S), of the Spanish Research Agency (AEI)

Here we describe methods for (a) collecting starfish during their breeding period; (b) maintaining adults with fully grown gonads in laboratory aquaria; (c) rearing fertilized eggs to brachiolaria larvae, and (d) inducing larvae to metamorphose into juveniles under laboratory conditions. Such protocols should facilitate various analyses of starfish development throughout the entire life cycle of these model organisms.

Cladocerans are a diverse group of species that show rapid responses to changes in environmental conditions. This adaptive capacity has important implications for egg production and life cycle, especially in transitory environments such as temporary waterbodies. The present study investigated the life history and egg production of Alona gutatta Sars, 1862 (Crustacea, Cladocera), an abundant and frequent species from a high-altitude temporary pond (Lagoa Seca, Minas Gerais, Brazil). Newly hatched neonates were monitored in relation to time of maturation, number of eggs produced per female and time of survival. Neonates required a mean of 8 days to mature. A. guttata survived for a mean of 30.9 ± 8.1 days and produced 2 eggs per brood, generating a mean of 10.95 ± 6.41 neonates during the entire life cycle. The rapid development, short time to produce eggs and long life cycle are important adaptations to the adverse environmental conditions of temporary aquatic environments, which can contribute to the rapid colonization of Alona guttata in transitory ecosystems. Resumo Os cladóceros formam um grupo diverso de espécies que apresentam respostas rápidas às mudanças nas condições ambientais. Essa capacidade adaptativa tem implicações importantes para a produção de ovos e para o ciclo de vida, especialmente em ambientes transitórios, como corpos d'água temporários. O presente estudo investigou a história de vida e a produção de ovos da espécie Alona guttata Sars, 1862 (Crustacea, Cladocera) coletada em uma lagoa temporária de altitude (Minas Gerais, Brasil). Organismos recém eclodidos foram observados (em condições de laboratório) em relação ao tempo de maturação, número de ovos produzidos por fêmea e tempo de sobrevivência. Os neonatos levaram em média 8 dias para atingir o primeiro estágio de maturação. As fêmeas produziram 2 ovos por ninhada e geraram uma média de 10,95 ± 6,41 neonatos durante todo o ciclo de vida. A. guttata apresentou uma média de 30,9 ± 8,1 dias de sobrevivência. O rápido desenvolvimento, o pouco tempo para a produção de ovos e o ciclo de vida longo são adaptações importantes às condições ambientais adversas de ambientes aquáticos temporários, que podem contribuir para a rápida colonização de Alona guttata em ecossistemas transitórios.

The great complexity of plant metabolism, with multiple subcellular compartments, cell types, tissues and organs, greatly complicates its analysis. This problem is compounded by the extensive changes that occur in metabolism over time, both during day/night cycles and throughout the course of an entire life cycle. In this context in silico network flux analysis, including both isotope labelling and stoichiometric modelling approaches, represent an important tool to study plant metabolism, providing a framework for the integration of data from a number of experimental strategies. Together, these methods have provided insight into the subcellular distribution of metabolic flux, the interactions between different cell types, source and sink relationships between organs, and how metabolic flux alters over time both at the cellular and whole plant scale. In this review we discuss how network flux analysis has contributed to our understanding of the spatial and temporal organisation of plant metabolism, looking in detail at key studies that address questions surrounding plant metabolism at different scales, from subcellular to whole plant.

The present study analysed the condition factor (K) and the hepato-somatic index (I H ) of the Brazilian sharpnose shark Rhizoprionodon lalandii during its entire life cycle. Discontinuity of liver growth was observed after sexual maturity. High condition values were recorded in the length classes of 300-350 mm (neonates), when the livers represented about 8% of total mass, decreasing until the length classes of 400-450 and 450-500 mm in females and males, respectively. Seasonal analysis exhibited low I H values in the summer, while for K, low values were in spring, indicating greater investment for body growth during spring and for gonad maturation in summer. Such findings indicate that this small coastal shark species accumulates reserve substances in the liver that will be used during reproduction. The decline in I H values in juveniles suggests that reserves provisioned by the mother to the neonate liver can be used in the first months of life.

Bromeliads constitute a good example of symbiosis with organisms that spend their entire life cycle inside the plants, and often depend on them to breed. The bromeliads benefit from this interaction by increasing their nutrients intake. Conservation efforts tend to focus on a single endangered species, but in symbiotic associations, the viability of one species depends on that of the other. Based on IUCN criteria, any species that depends on another to complete its life cycle should be assigned a conservation status equivalent to that of the host taxon, where appropriate. We gathered published plus fieldwork data on the frog-bromeliad mutualism and compiled a checklist of 99 bromeligenous frogs species associated to 69 bromeliad hosts, and found threatened bromeliads hosting non-threatened frogs. We found that 62% bromeligenous frogs inhabit unspecified bromeliads. Finally, we propose strategies for improving understanding and conservation of the frog-bromeliad mutualism.

The entire life cycle of influenza virus involves viral attachment, entry, replication, and release. Previous studies have demonstrated that neuraminidase (NA) is an essential glycoprotein on the surface of influenza virus and that it is responsible for release of progeny virions from the host cell to infect new cells. However, recent studies have also suggested that NA may play other roles in the early stages of the viral life cycle, that is, viral attachment and entry. This review focuses on the new role of NA in the early stages of influenza life cycle and the corresponding development of novel NA inhibitors. Copyright © 2016 John Wiley & Sons, Ltd.

Omosita colon (Linnaeus, 1758) (Coleoptera: Nitidulidae) is a species widely distributed in the Holarctic that usually appears during more advanced stages of decay. It is one of the species found on highly decomposed remains. Although O. colon may be a promising indicator of post-mortem interval (PMI) in cases with longer PMI, there is currently no existing research on its growth and development. Therefore, we studied the development of O. colon at seven constant temperatures between 16 and 34 °C and found that O. colon can complete its entire life cycle between 16 and 31 °C, but failed to complete development at 34 °C. At 16, 19, 22, 25, 28, and 31 °C, the developmental duration of O. colon from egg to adult is 95.3 ± 11.4, 62.4 ± 8.5, 45.9 ± 2.8, 34.9 ± 3.4, 30.0 ± 2.6, and 25.2 ± 2.6 d, respectively. Based on the results of development time and accumulated degree days, an isomorphen diagram was plotted and a thermal summation model was established. The mean (±SE) developmental threshold temperature D0 and the thermal summation constant K calculated using the thermal summation model were 10.65 ± 0.16 °C and 514.1 ± 8.7° days, respectively. The results of this study provide fundamental developmental data for the use of O. colon in minimum post-mortem interval (PMImin) estimations.

The brown dog tick is unusual among ticks in that it can complete its entire life cycle indoors as well as outdoors. Brown dog tick infestations can develop in dog kennels and residences, where populations can reach dramatic levels and cause dog diseases. This 6-page fact sheet written by and published by the UF/IFAS provides the distribution, description and identification, life cycle, and management of the brown dog tick as well as its hosts and the medical and veterinary significance of this troublesome pest. https://edis.ifas.ufl.edu/in378 This article is co-published with the Featured Creatures collection of UF/IFAS Department of Entomology & Nematology, and FDACS/DPI, available at http://entnemdept.ufl.edu/creatures/urban/medical/brown_dog_tick.htm

The purpose of this study was to identify chydoridae using conservative way, while the observations of the life cycle was done through a microscope to determine the egg production per parent and length of life. Individual chydoridae acclimatized to reach 10 generations (1 month), and 10 females were isolated for the production of seedlings. Based on literatures review, chydoridae used was derived from subfamily Aloninae (Alona spp.); while studies on the life cycle found: the egg size of chydoridae 150.2 ± 22.4 μm, and neonates have an average size of 291.82 ± 3.06 μm, and reached adult size after 2.3 ± 0.5 days, with an average size of 441.22 ± 10.2 μm. Time of embryonic development occured for 1-2 days. On the entire life cycle, only 2 eggs could be produced per individual. Based on this study, the number of eggs produced by the female during its lifetime ranges between 30-60 eggs. Similarly, the length of life of this organism on average 47.2 ± 11.7 days, with the longest lifespan was achieved 60 days. It was found also the maximum size was 1,037 ± 8.5 mm; while the average size of an organism's body was 800.42 ± 56.3 μm.Keywords: chydoridae, identification, life cycle, Alona spp

The seeds of Annona macroprophyllata Donn. Sm. contain idioblasts with toxic acetogenins, including laherradurin and rolliniastatin-2, in relatively high proportions. Both metabolites are cataloged as potent insecticides for several species, even so, the wasp Bephratelloides cubensis Ashmead fulfills almost its entire life cycle inside the seeds of this and other annonaceous species, to such a degree, that they constitute a strong selection pressure. In order to document the chemical relationship between the two species, it is reported for the first time in this paper the presence of idioblasts and acetogenins during the ontogenic development of the seeds of A. macroprophyllata, and contrasted with the development of B. cubensis. The results indicate that idioblasts with laherradurin and rolliniastatin-2 acetogenins are formed in the middle stages of the endospermic development, also that both acetogenins are biosynthesized simultaneously, and that their proportion is dependent on the degree of development. The acetogenins are present in high amounts that suppose a sufficient toxic barrier and, in this case, laherradurin is the most abundant (> 1000 µg g dry weight−1). The wasp B. cubensis only emerges from the seeds to copulate and returns for oviposition; its larval phase coincides with the appearance of acetogenins, so it feeds on the acetogenic endosperm. The absence of acetogenins in the tissues and excreta of the insect supposes a metabolization of the molecules, which would explain the tolerance to its toxicity.

Pharmaceuticals are nowadays recognized as a threat for aquatic ecosystems. The growing consumption of these compounds and the enhancement of human health in the past two decades have been paralleled by the continuous input of such biologically active molecules in natural environments. Waste water treatment plants (WWTPs) have been identified as a major route for release of pharmaceuticals in aquatic bodies where concentrations ranging from ng/L to μg/L are ubiquitously detected. Since medicines principles are designed to be effective at very low concentrations, they have the potential to interfere with biochemical and physiological processes of aquatic species over their entire life cycle. Investigations on occurrence, bioaccumulation and effects in non target organisms are fragmentary, particularly for marine ecosystems, and related to only a limited number over the 4000 substances classified as pharmaceuticals: hence, there is a urgent need to prioritize the environmental sustainability of the most relevant compounds. The aim of this review is to summarize the main adverse effects documented for marine species exposed in both field and laboratory conditions to different classes of pharmaceuticals including non-steroidal anti-inflammatory drugs, psychiatric, cardiovascular, hypocholesterolaemic drugs, steroid hormones and antibiotics. Despite a great scientific advancement has been achieved, our knowledge is still limited on pharmaceuticals behavior in chemical mixtures, as well as their interactions with other environmental stressors. Complex ecotoxicological effects are increasingly documented and multidisciplinary, integrated approaches will be helpful to clarify the environmental hazard of these "emerged" pollutants in marine environment.

Sturgeons are an ancient order of fish (Acipenseriformes), dating back in their occurrence to over 200 million years ago. The order comprises two families (Acipenseridae and Polyodontidae) and 27 species. Their natural range is restricted to the northern hemisphere. Sturgeons exhibit a very long life cycle (maximum lifespan up to over 150 years, depending on species). They are late-maturing species, and many grow to very large sizes (up to 6–7 m long). Most of the sturgeon species are anadromous. There are also potamodromous (landlocked) species and forms, spending their entire life cycle in freshwater (Fig. 26.1).

A whole life-cycle bioenergetic model based on the dynamic energy budget (DEB) theory was proposed for the three-spined stickleback (Gasterosteus aculeatus). To develop this model, experiments on growth and reproduction were performed: adult and juvenile growth, size at first reproduction and amount of eggs spawned by females were monitored under different feeding levels and temperatures. The DEB parameters were estimated, using Bayesian statistics, based on the data produced during these experiments and on other data found in the literature. The model fitted accurately the different data used for the calibration process and, in addition, predicted accurately the data sets used to assess its predictability. Our bioenergetic model of the whole life cycle of the three-spined stickleback accounting for environmental variations could contribute in many ways to improved ecological assessment: supporting change of scale from individual to populations; developing new biomarkers of exposure and effect; analysing ecotoxicity tests with biology-based models.

Life-history traits of two coexisting cladocerans, Daphnia magna Straus and Scapheloberis kingi Sars, inhabiting a temporary pond in north-eastern Algeria were monitored in 2013 under laboratory conditions. Their life histories were compared for differences in traits such as age and size at first reproduction, size of neonates, brood size, number of broods per female, total life span and intrinsic rate of increase (rm). Data were recorded during their entire life cycle. Daphnia magna, the larger species, could possibly be more successful in colonising temporary habitats than S. kingi because it allocates more energy to reproduction. Scapheloberis kingi, the smaller species, starts reproduction early, resulting in a smaller brood size and a shorter life span with fewer broods. Consequently, S. kingi produces a smaller number of neonates during its lifetime and has a lower rm. In contrast, D. magna delays reproduction but produces a larger brood size and, because it is longer-lived, produces more broods and...

Summary The current study aims to update the range of Aphanius fasciatus occurring in inland aquatic systems, and to characterise the length–weight relationship of specimens caught in inland waters of the Northern Sahara of Algeria. Although the known distribution of A. fasciatus is restricted to coastal waters including islands of the Mediterranean region, visits to 39 hydrosystems in Northeast Algeria revealed the presence of the species at two sites: Oued Still and Lake Temacine. Both sites are in the Sahara Desert of Algeria, where the climate is hot and hyperarid. The surveyed populations perform their entire life cycle at the same sites. Analysis of a sample composed of 27 individuals captured in Oued Still allowed determination of the length–weight relationship. On average, females measured 4.2 ± 0.6 cm in length and weighed 1.1 ± 0.5 g; males were 3.2 ± 0.6 cm and 0.5 ± 0.2 g. Growth parameters of the von Bertalanffy equation for A. fasciatus were estimated at Lt = 5.5145 (1−exp (−0.341(t−0.0049))), Wt = 2.6692 (1−exp (−0.271t))3.

Functional genomics research is the core field in plant scientific research. As a staple food crop and a reference of monocot plant, tremendous progress has been made in rice functional genomics in China. Various methods and technical platforms have been developed to enable high-throughput analyses and effective determination of gene functions, including: large T-DNA insertion mutant libraries; global gene expression profiles for the entire life cycle of rice growth and development, abiotic and/or biotic conditions; full-length cDNA clones; high-throughput genotyping by whole-genome resequencing; large-scale analyses of metabolome and reliable high- throughput phenotyping platforms, etc. With those enabling tools and genetic resources, large efforts have been focused on identifying genes controlling yield, fertility, superior quality, resistances to biotic and abiotic stresses, and high nutrient-use efficiency. The combination of approaches based on the advances in genomic research has been formulated to develop rice cultivars referred to as Green Super Rice (GSR). We briefly summarize these advances and call for the prospects in future proposed by Chinese scientists: the RICE2020 Project and the RICE 4D Genome Program.

Background Domestication is an important and contested concept. Insects are used as food worldwide, and while some have been described as domesticated and even ‘semi-domesticated’, the assumptions and implications of this designation are not clear. The purpose of this paper is to explore these aspects of insect domestication, and broader debates in domestication studies, through the case of edible wasps in central rural Japan. Methods Both authors conducted ethnographic fieldwork with communities in central rural Japan. Fieldwork comprised participant observation, semi-structured interviews, quantitative surveys and a review of resources including the personal and public records of wasp collectors. Results The practice of keeping wasps in hive boxes has historical roots and has changed significantly within living memory. Current attempts to further develop the practice involve collectors’ great efforts to keep new queens during their hibernation. Collectors have also tried, still without success, to keep wasps living within a human-made enclosure for their entire life cycle. These and other practices are costly in both time and money for collectors, who emphasise enjoyment as their primary motivation. At the same time, they also engage in practices such as pesticide use that they recognise as damaging to wasp ecology. Conclusions These practices can be understood to some extent in domesticatory terms, and in terms of care. We develop a framework for understanding domesticatory practices of insect care, discuss how this case contributes to ongoing debates within domestication studies, and recommend further research to be pursued.

This study presents a method based on life cycle assessment to reduce and simplify the decision-making process and to identify the best available techniques of a product. This procedure facilitates the selection of a technical alternative from an environmental point of view and the reduction of emission levels and the consumption of energy and primary resources. This method comprises the following four steps: (i) the identification of the current techniques of a specific product, (ii) the application of a life cycle assessment to determine the hot spots, (iii) the proposal of the best available techniques and (iv) the development of a best available techniques reference document (step not implemented in our case study). The Cantabrian anchovy canning industry is selected as a case study due to the importance of this sector from economic, social and touristic points of view. An entire life cycle assessment of one can of anchovies in extra virgin olive oil is conducted. The results indicated that the hot spots of the life cycle were the production of aluminium cans (for packaging) and extra virgin olive oil and the management of the packaging waste. According to these results, the study proposes several improvements, such as packaging recycling and several best available techniques for the canned anchovy product. The authors thank the Ministry of Economy and Competitiveness of the Spanish Government for their financial support via the project GeSAC-Conserva: Sustainable Management of the Cantabrian Anchovies (CTM2013-43539-R) and to Julia Celaya for her technical support. Jara Laso thanks the Ministry of Economy and Competitiveness of Spanish Government for their financial support via the research fellowship BES2014-069368. Pere Fullana y Alba Bala thanks the UNESCO Chair in Life Cycle and Climate Change.

Anagyris foetida L. has a Mediterranean distribution, but its populations are highly fragmented. This, together with its mixed mating system, puts it at clear risk of being strongly affected by inbreeding depression. To determine the effect of inbreeding depression in this species, hand pollinations were performed during the 2003/04 season in 2 populations from SW Spain to generate selfed and outcrossed seeds. These seeds were divided in 2 sample lots and seedlings were obtained in different years. During the first year of life the first lot showed no differences in vegetative parameters between the 2 populations, so that no differentiation was made between populations in analyzing the results. Reproductive parameters were determined during the first 2 flowering periods in the second sample lot. The results showed inbreeding depression to be manifest in the populations studied throughout the life cycle, adversely affecting the reproductive parameters more than the vegetative parameters, with the male capacity being strongly affected. This shows the need to study the entire life cycle to understand how it is affected by inbreeding depression, and to analyze more than one flowering period in long-lived species. The findings may have important implications for the long-term conservation management of these populations.

A major skeletal problem of conventional- ly caged hens is increased susceptibility to osteoporosis mainly due to lack of exercise. Osteoporosis is charac- terized by a progressive decrease in mineralized struc- tural bone. Whereas considerable attention has been given to enriching laying cages, little research has been conducted on providing caged pullets with furnish- ments, in particular perches. The objective of the cur- rent study was to determine if metal perches during all or part of the life cycle of White Leghorns affected hen musculoskeletal health, especially at end of lay. Treat- ments during the pullet phase (hatch to 16.9 wk) en- tailed cages with and without perches. Four treatments were used during the laying phase (17 to 71 wk of age). Treatment 1 chickens never had access to perches at any point during their life cycle, typical of egg industry practices in the United States for conventional cages. Treatment 2 chickens had access to perches only during the egg-laying phase, which was from 17 to 71 wk of age. Treatment 3 chickens had access to perches only during the pullet phase (0 to 16.9 wk of age). Treatment 4 chickens had perch access throughout their entire life cycle (0 to 71 wk of age). Musculoskeletal health was assessed by measuring muscle weights, bone mineraliza- tion, bone fracture incidence, and keel bone deviations. Muscle deposition of 71-wk-old hens increased when given access to perches as pullets. Bone mineralization of 71-wk-old hens also increased if given perch access as adults. However, the disadvantage of the adult perch was the higher incidence of keel deviations and keel fractures at end of lay. The increase in bone mineraliza- tion of the keel bone as a result of perch access during the pullet and laying phases was not great enough to prevent a higher incidence of keel bone fractures at end of lay. Perch redesign and placement of perches within the cage to minimize keel fractures and deviations are possible solutions.

Extensive individual variation in spatial behaviour is a common feature among species that exhibit migratory life cycles. Nowhere is this more evident than in salmonid fishes; individual fish may complete their entire life cycle in freshwater streams, others may migrate variable distances at sea and yet others limit their migrations to larger rivers or lakes before returning to freshwater streams to spawn. This review presents evidence that individual variation in migratory behaviour and physiology in salmonid fishes is controlled by developmental thresholds and that part of the variation in proximal traits activating the development of alternative migratory tactics is genetically based. We summarize evidence that alternative migratory tactics co-exist within populations and that all individuals may potentially adopt any of the alternative phenotypes. Even though intra-specific genetic divergence of migratory tactics is uncommon, it may occur if female competition for oviposition sites results in spawning segregation of alternative phenotypes. Because of their polygenic nature, alternative migratory tactics are considered as threshold traits. Threshold traits have two characteristics: an underlying 'liability' trait that varies in a continuous fashion, and a threshold value which is responsible for the discreetness observed in phenotypic distribution. We review evidence demonstrating that body size is an adequate proxy for the liability trait controlling the decision to migrate, but that the same phenotypic outcome (anadromy or residency) may be reached by different developmental pathways. The evidence suggesting a significant heritable component in the development of alternative migratory tactics is subsequently reviewed, leading us to conclude that alternative migratory tactics have considerable potential to respond to selection and evolve. We review what is known about the proximal physiological mechanisms mediating the translation of the continuous value of the liability trait into a discontinuous migratory tactic. We conclude by identifying several avenues for future research, including testing the frequency-dependent selection hypothesis, establishing the relative importance of adaptive phenotypic plasticity in explaining some geographic gradients in migratory behaviour and identifying the physiological and genetic basis of the switching mechanisms responsible for alternative migratory tactics.

Protonemura gevi is a Palearctic stonefly with unique morphological adaptations for a cavernicolous life. In this study, the development, nymphal and adult feeding, adult behavior, and mate encounter mechanisms of this species are investigated. This species inhabits a stream flowing through a cave, in darkness and at a constant temperature. Nymphs of different sizes cohabit throughout the whole year, showing a nonseasonal life cycle. Nymphs at the entrance of the cave feed mainly on coarse particulate organic matter and hyphae, and nymphs at the end of the cave feed principally on detritus and occasionally on animal matter. Adults were present year-round and aggregated on emergent stones at the end of the cave. No drumming signals were recorded; therefore, this species seems to rely mainly on aggregation to maximize pair encounters. As shown in this study, P. gevi have adaptations suited to life in the dark and the completion of its entire life cycle inside a cave.

According to the samples of Ommastrephes bartramii collected by Chinese squid jigging vessels fro July to October in 2007 in the Northwest Pacific Ocean,the ratio of statolith maximum width(MW) to to statolith length(TSL),as an indicator of shape change of statolith,was analyzed in different sexual maturi stages and individual sizes using the method of ANOVA and LSD.The results indicated that the statolith gre constantly in the entire life cycle of O.bartramii.MW/TSL values between sexual maturity stage Ⅰ and Ⅱ Ⅲ,Ⅳ,Ⅴ showed significant differences,and MW/TSL values among sexual maturity stage Ⅱ,Ⅲ,Ⅳ and showed no significant differences.We conclude that the statoliths of O.bartramii hardly change their shape af the sexual maturity stage I.Between the four groups whose mantle length were less than 280 mm and most oth groups,MW/TSL values showed significant differences,and MW/TSL values among groups whose man length were more than 280 mm,showed no significant differences.We conclude that the statoliths of O bartramii hardly change their shape after mantle length of 280 mm.Mantle length of 200 to 280 m corresponds with sexual maturity stage Ⅰ,and the period O.bartramii to with mantling length of 200 to 2 mm corresponds to the days for O.bartramii migrate into the sub-Arctic waters.MW/TSL might serve as valid indicator of sexual maturity and early ontogenetic shifts for the squid O.bartramii.

Filopodia are key structures within many cells that serve as sensors constantly probing the local environment. Although filopodia are involved in a number of different cellular processes, their function in migration is often analyzed with special focus on early processes of filopodia formation and the elucidation of filopodia molecular architecture. An increasing number of publications now describe the entire life cycle of filopodia, with analyses from the initial establishment of stable filopodium-substrate adhesion to their final integration into the approaching lamellipodium. We and others can now show the structural and functional dependence of lamellipodial focal adhesions as well as of force generation and transmission on filopodial focal complexes and filopodial actin bundles. These results were made possible by new high resolution imaging techniques as well as by recently developed elastomeric substrates and theoretical models. The data additionally provide strong evidence that formation of new filopodia depends on previously existing filopodia through a repetitive filopodial elongation of the stably adhered filopodial tips. In this commentary we therefore hypothesize a highly coordinated mechanism that regulates filopodia formation, adhesion, protein composition and force generation in a filopodia dependent step by step process.

This study examined the biological characteristics of the insect and examined potential cultural controls using peduncle topping methods. Ginseng stem fungus gnat eggs hatched after 5 days; ecdysis lasted 3-4 weeks, and after 5 days pupation, adults emerged. Adults deposited eggs 1-2 days after emerging, and the entire life cycle lasted 32-40 days. The fungus gnats laid eggs 327 × 220 μm in size on cut planes of stems, but not on intact stem parts that had not been topped or wounded. Analyses of major weather data for the experimental areas and weather data for the past 30 years acquired from the Korea Meteorological Administration revealed that fungus gnat dispersion was prevalent under highly humid conditions and in areas with thick and frequent fogging. Among the topping times examined, fungus gnat damage to ginseng was lowest when topping occurred in late May. Among the five different topping methods evaluated on experimental ginseng farms, the cumulative fungus gnat damage to ginseng was low (0.8%) under partial peduncle topping (removal of peduncle with lateral fruit remaining) and removal of only flower buds (0.6%), with fungus gnat control effects of 82% and 86%, respectively, compared to conventional topping (removal of peduncle about 5 cm above its base). No fungus gnat damage to ginseng was observed under the no-topping treatment. These results suggest that partial topping of peduncles, while letting lateral fruits remain, is a potentially environmentally friendly method of controlling the ginseng stem fungus gnat.

[EN] The rapid evolution of materials and manufacturing processes, driven by global competition and new safety and environmental regulations has had an impact on the automotive structures (BIW) manufacturing.The need for lighter vehicles, whit more equipment, safer and at the same time friendly to the environment, covers the entire life cycle of the car.Carmakers and steelmakers agree that weight reduction is possible, and the solution go through the new Advanced High-Strength Steels.Thinner and stronger materials lead to higher demands on stamping, the manufacturing system most used manufacturing BIW parts. In this context of persistent innovation the lubrication of surfaces is a problem associated with the change.After the question about the best lubricant to form these new materials, it was researched about characteristics and performance of known simulation equipment. An edges of punch and die drawing simulator was used. Two materials have been selected of AISI portfolio. DP600 for being one of most used in BIW frames, and TWIP is a new steel to evaluate, and with an extraordinary strain. They are designed and manufactured tools for the manufacture of the specimens.It has defined a simplified deformation model. It was developed a measurement protocol with twelve parameters that compare the behaviour of lubricants in the simulator. It was selected the best for each type of material by Factorial Experiments Design and efficiency parameters have been used to select the best one.The model has been applied to the formed specimens and is able to answer the initial question. Simultaneously it has been able to make the technological evolution of system simulation and measurement protocol, [ES] La rápida evolución de los materiales y procedimientos de fabricación, impulsada por una competencia globalizada y nuevas regulaciones de seguridad y medio ambiente ha tenido un fuerte impacto en la fabricación de estructuras de automóviles (BIW).La necesidad de vehículos con menos peso, con más equipamiento, más seguros y al mismo tiempo, respetuosos con el medio ambiente, abarca todo el ciclo de vida del vehículo.Constructores y fabricantes de acero están de acuerdo en que todavía hay margen para para la reducción, y la solución pasa por los nuevos Aceros Avanzados de Alta Resistencia.Materiales más delgados y más resistentes llevan a mayores exigencias en el conformado por estampación, que es el sistema de fabricación que abarca una mayor propor-ción de piezas y peso del chasis de vehículos ligeros. En este contexto de innovación persistente la lubricación de las superficies rozantes es un problema asociado al cambio. Tras formular la cuestión sobre el lubricante más adecuado para conformar estos nuevos materiales, se ha realizado una investigación sobre los equipos de simulación co-nocidos, sus características y prestaciones. Se ha utilizado un simulador del proceso de estampación referido a los bordes de punzón y matriz. Se han seleccionado dos materiales dentro de la propuesta de AISI. El DP600 por ser uno de los más utilizados en la construcción de la estructura, y el TWIP que es una novedad a evaluar, y con un extraordinario comportamiento en su deformación. Se han diseñado y construido útiles para la fabricación de las probetas.Se ha definido un modelo de deformación simplificado para la evaluación del comportamiento. Se ha desarrollado un protocolo de medición con doce parámetros que permiten comparar el comportamiento de los lubricantes en el simulador. Se han seleccionado los mejores para cada tipo de material mediante un Diseño de Experimentos Factorial y se han definido parámetros de eficiencia para tomar los mejores candidatos.Se ha aplicado el modelo a los materiales conformados y se ha podido responder a la cuestión inicial. Al mismo tiempo se ha podido realizar la evolución tecnológica del sistema de simulación y el protocolo de medida., [CAT] La ràpida evolució dels materials i procediments de fabricació, impulsada per una competència globalitzada i noves regulacions de seguretat i medi ambient ha tingut un fort impacte el la fabricació d'estructures d'automòbils (BIW)La necessitat de vehicles amb menys pes, amb més equipament, més segurs i al mateix temps respectuosos amb el medi ambient, comprén el procés integral del vehicle. Constructors i fabricants d'acer estan d'acord en què encara hi ha marge para per a la reducció, i la solució panses pels nous Acers Avançats d'Alta Resistència.Materials més prims i més resistents porten a majors exigències en el conformat per estampació, que és el sistema de fabricació que comprén una major proporció de peces i pes del xassís de vehicles lleugers. En este context d'innovació persistent la lubricació de les superfícies rozantes és un problema associat al canvi.Després de formular la qüestió sobre el lubricant més adequat per a conformar estos nous materials, s'ha realitzat una investigació sobre els equips de simulació coneguts, les seues característiques i prestacions. S'ha utilitzat un simulador del procés d'estam-pació referit als bords de punxó i matriu. S'han seleccionat dos materials dins de la proposta d'AISI. El DP600 per ser un dels més utilitzats en la construcció de l'estruc-tura, i el TWIP que és una novetat a avaluar, i amb un extraordinari comportament en la seua deformació. S'han dissenyat i fabricat útils per a la fabricació de les provetes.S'ha definit un model de deformació simplificat. S'ha desenrotllat un protocol de me-surament amb dotze paràmetres que permeten comparar el comportament dels lubricants en el simulador. S'han seleccionat els millors per a cada tipus de material per mitjà d'un Disseny d'Experiments Factorial i s'han definit paràmetres d'eficiència per a prendre els millors candidats i el model de simular.S'ha aplicat el model als materials conformats i s'ha pogut respondre a la qüestió inicial. Al mateix temps s'ha podi realitzar l'evolució tecnològica del sistema de simulació i el protocol de mesura., Plá Ferrando, R. (2015). Investigación de las condiciones tribológicas en el conformado de elementos estructurales de Aceros Avanzados de Alta Resistencia en vehículos [Tesis doctoral no publicada]. Universitat Politècnica de València. doi:10.4995/Thesis/10251/59222., TESIS

The infraorder Nepomorpha is one of the most specialized groups of heteropterans, with most of its species spending the entire life cycle within the water. True water bugs include ten families, 52 genera, and approximately 730 species in the Neotropical region, which shelters about 30 % of the global diversity of the group. Despite this fact, little is known about their biology, ecology, and geographical distribution in the Neotropics. Several genera need to be revised and many species remain with outdated descriptions. The systematics of the infraorder, although has received little attention in recent years, remains with various unresolved questions, and no phylogenetic study was conducted for any endemic group of this region.

Complex life-histories are common in nature, have many important biological consequences, and are an important focal area for integrative biology. For organisms with complex life-histories, a legacy is something handed down from an ancestor or previous stage, and can be genetic, nutritional/provisional, experiential, as well as the result of random chance and natural variation in the environment. As we learn more about complex life-histories, it becomes clear that legacies are inexorably linked in the short- and long-term through ecology and evolution. Understanding the consequences and drivers of life-history patterns can therefore only be understood by considering all types of legacies and integrating legacies across the entire life cycle. Larry McEdward was a leader in the field of ecological physiology, and evolutionary ecology of marine invertebrate larvae with complex life-histories. Through his scientific work and publications, devotion to students, colleagues, family, and friends, Larry has left a lasting legacy that will impact the future development of the field of larval ecology and complex life-histories.

Although the crab Hymenosoma orbiculare appears to complete its entire life cycle within estuaries, the salinity and temperature requirements for its successful larval development are not known. The present study therefore evaluated larval response to salinity and temperature in combination. Larvae were reared individually in factorial combinations of salinity (14, 21, 28, 42 and 49 ppt) and temperature (12, 16, 20, 24, 28 and 32°C). Both parameters influenced the probability of survival for any individual larva. Highest survival occurred at salinities of between 21–35ppt for the Zoea 1 and 2 and of between 28–35ppt for the Zoea 3, with optimum temperature ranges narrowing substantially from Zoea 1 through Zoea 2 to Zoea 3. Temperature exerted a similar influence on development rate at all rearing salinities within each zoeal stage. However, elevated salinity (42 ppt) delayed development. H. orbiculare larvae appear to be well adapted to tolerate salinities typical of the estuarine environment, but the ra...

Pines are known to produce one seed crop each year and mature about 20 months after pollination. The entire life cycle may take two to three years. Recent observations, however, show that a greater number of crops may develop annually and that cone development may be faster. In Pinellas County, Florida, Pinus clausa and P. elliottii now have three seed crops annually, and consequently, more seeds during the year. Also, there is no dormant phase from pollination time to seed maturity in the primary (most abundant) crop of these species. The reason for this change in reproductive strategy is thought to be as a response to climatic changes, in particular, CO2 levels. Pines seem to be reacting to increases of available atmospheric CO2 that fluctuate seasonally. The gas may act as a biochemical switch for developmental stages and be a mechanism for controlling cone growth. Furthermore, there are definite phenological shifts forward in the primary seed crops of P. clausa (about 105 days) and P. elliottii (about...

Morphogenesis and nuclear events during conjugation have been investigated for the aloricate oligotrich Pelagostrobilidium sp. using cytological staining methods. While several similarities between Pelagostrobilidium and sister groups (hypotrichs and stichotrichs) reported previously were recognized in the preconjugation behaviour, conjugation type and general nuclear division patterns, significant differences were found between them in the behaviour of oral and somatic ciliatures. In Pelagostrobilidium there was no reorganization in the somatic kineties during conjugation, in addition, it showed a very simple pattern of reorganization in the oral ciliature, which was very similar to stomatogenesis in asexual reproduction. A replacement oral apparatus was completed during the conjugation process and it very quickly replaced the old adoral zone when the conjugants separated. A noteworthy fact is that most of the parental adoral membranelles of Pelagostrobilidium persisted and were active during the entire conjugation period in spite of the loss of functional feeding organelles such as the cytostome and paroral membrane. The need to retain locomotion throughout the entire life cycle might be one of the adaptive features of oligotrichs required to occupy a certain niche in oceanic waters. The relatively short duration of the conjugation process (5.6 h) of Pelagostrobilidium is also likely to be important for life in oceanic waters.

Abstract Rearing damselflies under laboratory conditions is a promising means of solving a variety of biological questions. Therefore, in order to improve the success of future researchers we felt the need to indicate potential difficulties in carrying out rearing experiments. Laboratory crosses were obtained using virgin animals originating from natural populations in Belgium and Spain. Resulting offspring was maintained, under laboratory conditions, in small aquaria until emergence and in insectaries as adults. Our results show that keeping damselflies during their entire life cycle under artificial conditions can be very difficult. We suggest that future researchers should change water regularly, supply sufficient food, and rear animals at low density or even individually. Furthermore, suggestions are given on type of food, advisable laboratory conditions and female oviposition methodology.

Optimal defense theory (ODT) predicts that plants should have the highest defense levels in parts that have the highest value in terms of fitness. Assumptions about differences in fitness value among plant parts have previously been based on general reasoning, e.g., that reproductive tissue is more valuable than vegetative tissue since fitness ultimately depends on reproduction. Here we present a first example of how demographic elasticity (proportional sensitivity) analysis can be used as a tool to generate more objective and specific estimates of the fitness value of different plant parts, based on the entire life cycle. These estimates were further used to generate testable predictions about intraplant variation in defenses of the brown seaweed Ascophyllum nodosum (knotted wrack). The predictions were clearly supported by the results from both analyses of chemical defense levels (phlorotannins) and bioassays (feeding preference experiments), which showed that reproductive tissues had the lowest defense level of the three examined tissue types, in contrast to previous assumptions. We suggest that a stronger focus on variation in life history among species and populations, with demographic perturbation analysis as one important tool, could lead to a better understanding of intraplant variation in defense levels, in seaweeds as well as vascular plants and other modular organisms.

Summary Thousands of Chinese sturgeon, Acipenser sinensis, have been grown since the 1990s, with some of them being used for close-cycle captive breeding. However most of the specimens have not yet matured, and there has been no literature on the Chinese sturgeon that matured when spending its entire life cycle in freshwater. We investigated the gonads of cultured Chinese sturgeon at ages ranging between 7 and 11 years when raised from captive broodstocks. Most of the 11 year-old fish (body weight 45.5–84 kg) were in the gonadal development stage. The maximal oocyte diameter of the females was about 500 μm. In 14 males at age 10–11 years, we found various stages of development but one dead specimen that seemed to have testis in the early stage of maturation, with all types of spermatocytes being present. This specimen was 10 years old (body weight 40.3 kg). According to the results obtained, the Chinese sturgeon cultured in freshwater were not yet fully mature but are assumed to likely reach maturity in the near future.

Various biosynthesised compounds from ornamental plants can be harmful to man, throughout a plant’s entire life cycle or only during certain moments, present in all of its organs or restricted only to some. Interdisciplinary research regarding plant toxins and allergens are being conducted worldwide, aiming to prevent the production of diseases. The research aimed to phytochemically classify vegetal compounds with toxic and allergenic characteristics found in ornamental plants, to identify the main pathogenic pathways through which these compounds act and to come up with recommendations regarding valorification of these plants. The study focuses on ornamental plants in both spontaneous and cultivated flora, in protected or unprotected spaces, commonly met in Romania. The current review includes vegetal allergens in the toxic vegetal substances group, from the perspective of modern definitions of toxicity. Based on phytochemical criteria, a classification of toxic vegetal compounds (including allergens) was achieved. Common native toxic ornamentals from our habitat are tabulated. Some non-native species were included on the basis of their high presence as house plants. Correlated to the commercial practices in Romania, the risks for ambient health were identified, both at the work place, at home and in the public space. Ornamentals can be dangerous to man’s health. The majority of toxic and allergenic substances (excluding pollens) are secondary metabolism compounds. Given these risk factors to health, it is necessary to impose health and safety regulations at work, to inform the general population regarding potential negative effects and to commercialize plants with labels which should contain warnings about the risk of diseases or the aggravation of existing ones.

Reproductive performance data were collected for inland fall chinook salmon Oncorhynchus tshawytscha from Lake Oahe, South Dakota, in 1988 and 1998. This population exists outside the native geographical range of chinook salmon and completes its entire life cycle in freshwater. Female weights and lengths, total fecundity, relative fecundity (eggs/mm), egg size, and egg survival were all considerably less than reported for anadromous chinook salmon stocks in their native range. Mean weight of spawning females was 2.73 kg in 1988 and 2.01 kg in 1998. Total fecundity was not significantly different at 2,892 eggs in 1988 and 2,496 eggs in 1998. Egg survival to the eyed stage averaged 37.7% in 1988 and 43.8% in 1998 and ranged from 0% to 96%. Relative fecundity (eggs/kg), egg size, and egg survival to the eyed stage were similar for each year. Relative fecundity (eggs/mm of total length) declined from 1988 to 1998. Total fecundity was linearly related to fish length in 1998 and in both years combined....

This study reports on a new parasite of the digestive gland of the queen conch, Strombus gigas. An intense and generalized sporozoan infection was detected during a reproductive study of S. gigas in San Andres island (Colombia). The parasite was found in the digestive gland of every sampled S. gigas, with a heavy intensity of infection (invasion of every cell) in many animals. The infection of the digestive gland began in the cryptic cells and later secretory cells were also infected, giving way to discharge of sporocysts to the stomach through the digestive gland ducts. Apicomplexa-like trophozoites were embedded in the digestive gland epithelial cells and attached to host cell wall by their conoid end. Several stages were detected: trophozoites, sporocysts, and gamonts containing macrogametes or microgametes. Given the presence of multiple stages at the same time, the entire life cycle of the parasite is assumed to occur within the same host and tissue. The taxonomic position of the parasite sh...

differ in adding a long parallel-sided anterior section to their tube-cases, shortly before pupation. They pupate in the newly built section, discarding the slightly conical larval case. Literature data suggest that two additional species of Micrasema exhibit similar behaviour. Production of a special section of tube-case for pupation is remi­ niscent of the situation in the primitive suborders Annulipalpia and Spicipalpia which build a pupal case which is often the only construction during the entire life cycle. It is uncertain if the behaviour of Micrasema is atavistic, or if it developed indepen­ dently.

A yellow colour form of Aphis schneideri (Born.) was found in Pilaitė (the surroundings of Vilnius, Lithuania) in 1994. Colour differences between yellow and green aphids of A. schneideri seem to have a genetic background. The yellow aphids were smaller, and the yellow clones did not finish their entire life cycle, thus supporting the idea of the reduced fitness of yellow mutants. There also exists the possibility of the hybridogenic origin of yellow colour forms in currant inhabiting species of the genus Aphis L.