The biology of two species of Engaeus (Decapoda : Parastacidae) in Tasmania. II. Life history and larval development, with particular reference to E. cisternarius

1977 ◽  
Vol 28 (1) ◽  
pp. 85 ◽  
Author(s):  
PJ Suter
Keyword(s):  
Life History ◽  
Larval Development ◽  
Early Spring ◽  
Late Autumn

The life history and larval development of Engaeus cisternarius are described; comparisons with E. fossor are made. Incubation of the eggs and of the young lasts about 6 months, between spring and autumn. The number of eggs carried by the females increases with the length of the cephalo- thorax, but E. cisternarius carries fewer eggs than similarly sized E. fossor. Mature females moult in early spring and late autumn.

The life history of shoots of Carex lacustris

1975 ◽  
Vol 53 (3) ◽  
pp. 256-260 ◽  
Author(s):  
John M. Bernard
Keyword(s):  
Life History ◽  
Water Level ◽  
Early Spring ◽  
Basal Diameter ◽  
Late Autumn ◽  
History Of ◽  
Carex Lacustris

Most shoots of Carex lacustris live for about 12–14 months, emerging in autumn, overwintering as shoots of up to 50 cm in length, and maturing during the next summer. Others emerge in early spring but both groups die in late autumn. A third class emerges in late July or August, grow to be over 50 cm in length, and die in late autumn, living only 2 or 3 months.Flower initials in this species begin growth in the September–October period and overwinter while about 1.0 cm in length. The shoots that develop inflorescences are in general longer, heavier, and have a greater basal diameter than those shoots which do not flower. More shoots flower if the water level in the marsh was high the previous year.

Laval development of the Megabalanine Balanomorph Austromegabalanus nigrescens (Lamarck) (Cirripedia, Balanidae)

1987 ◽  
Vol 38 (4) ◽  
pp. 511 ◽  
Author(s):  
EA Egan ◽  
DT Anderson
Keyword(s):  
Larval Development ◽  
Long Range ◽  
New South ◽  
New South Wales ◽  
Mantle Cavity ◽  
Early Spring ◽  
Dorsal Shield ◽  
Late Autumn ◽  
Larval Stages ◽  
South Wales

The presence of embryos in the mantle cavity of A. nigrescens was monitored over a 2-year period. A, nigrescens maintains some breeding individuals throughout the year but shows peak breeding during the late autumn, winter and early spring in the vicinity of Sydney, New South Wales, Australia. The larval stages of A. nigrescens are described from larvae reared in the laboratory. A. nigrescens larvae can be easily distinguished from other nauplii described from balanomorphs of New South Wales by their distinctive marginal spines and paired dorsal shield spines. The duration of larval development in A. nigrescens, 13-23 days, is similar to that of other Australian balanids and does not appear to accord with the concept that the distribution of Austromegabalanus species has involved long-range epiplanktonic dispersal. The separation of Austromegabaianus, Notomegabalanus and Megabalanus is supported by larva! differences.

THE LIFE HISTORY OF LESTES CONGENER (ODONATA: ZYGOPTERA) ON THE CANADIAN PRAIRIES

1974 ◽  
Vol 106 (4) ◽  
pp. 367-376 ◽  
Author(s):  
W. W. Sawchyn ◽  
C. Gillott
Keyword(s):  
Life History ◽  
Embryonic Development ◽  
Larval Development ◽  
Sexual Maturation ◽  
Low Temperatures ◽  
Canadian Prairies ◽  
History Of

AbstractLestes congener Hagen overwinters in the egg stage. There is a diapause just before blastokinesis, during which the egg is extremely resistant to low temperatures and desiccation. Post-diapause embryonic development can occur near 0 °C but will not take place until the eggs are wetted as the pond habitat fills in the spring. Hatching does not occur until the temperature exceeds about 5 °C and is highly synchronous. Larval development is rapid and is completed in the field in about 50 days. Emergence of the adults also is synchronous. Sexual maturation requires 3 weeks. Oviposition occurs immediately after copulation while the pair are still in tandem. It takes place only in dry stems of Scirpus. Adaptations of L. congener for life under rigorous prairie conditions are discussed.

The survey of wild birds for West Nile virus in Poland

2011 ◽  
Vol 14 (4) ◽  
pp. 573-577 ◽  
Author(s):  
J. Niczyporuk ◽  
E. Samorek-Salamonowicz ◽  
W. Kozdruń ◽  
Z. Mizak
Keyword(s):  
West Nile Virus ◽  
Genetic Material ◽  
Early Spring ◽  
Wild Birds ◽  
Rt Pcr ◽  
West Nile ◽  
Late Autumn ◽  
The Brain

The survey of wild birds for West Nile virus in PolandTwo thousand one hundred and forty birds belonging to 39 different species from different locations in Poland were examined. The study has taken place from the early spring till late autumn 2007-2010 when the activity of the mosquitoes was the highest. The brain samples were taken from the birds and whole cellular RNA was isolated, then the RT-PCR and NRT-PCR were performed to detect the presence of West Nile virus (WNV). The obtained results were confirmed by the commercial WNV Kit. No genetic material of WNV was found in the examined samples.

Colonization patterns and life-history dynamics of Culex mosquitoes in artificial ponds of different character

1993 ◽  
Vol 71 (3) ◽  
pp. 568-578 ◽  
Author(s):  
D. Dudley Williams ◽  
Annette Tavares-Cromar ◽  
Donn J. Kushner ◽  
John R. Coleman
Keyword(s):  
Life History ◽  
Dissolved Oxygen ◽  
Water Temperature ◽  
Larval Development ◽  
Development Time ◽  
Larval Density ◽  
Strong Relationship ◽  
Terrestrial Vegetation ◽  
Widespread Species ◽  
Artificial Ponds

The relationship between the biology and habitat of larval mosquitoes was studied in a series of artificial ponds of differing characteristics established across a terrestrial vegetation gradient from open fields to deep woods. The ponds were uniformly colonized by two widespread species of Culex, both characteristic of small bodies of water, including artificial, "container" habitats. First-instar larvae of Culex restuans were found within 2 days of filling the ponds with water and four or five generations were produced from May until the end of September. One very long generation occurred in July, which corresponded to maximum larval densities. Overall, there was a strong relationship between larval development time of C. restuans and larval density. A few larvae of Culex pipiens pipiens occurred sporadically throughout the summer, but numbers did not increase until C. restuans populations began to wane in late July. Thereafter two, or possibly three, generations were produced into the autumn. The patterns of colonization, synchrony of life history, and growth of these two species were remarkably consistent amongst the ponds, despite considerable variation in both their physical and biological environments (e.g., over the 2 years of study, conductivity ranged from 20 to 890 μS, pH from 6.4 to 10.7, dissolved oxygen from 0 to 13.5 ppm, and water temperature from 5 to 29.8 °C). Density of C. restuans was related to water temperature and pH at the "open" site and to water temperature, dissolved oxygen, percent algae, and percent detritus at the "edge of the woods" site. At the "deep woods" site, larval numbers were related to temperature, pH, conductivity, and dissolved oxygen. At both the edge and deep wood sites, larval development time of C. restuans increased with mean water temperature to 20 °C. Above this temperature, larval development time tended to decrease.

Phellinus igniarius. [Descriptions of Fungi and Bacteria].

1968 ◽  
Author(s):  
D. N. Pegler
Keyword(s):  
Great Britain ◽  
North America ◽  
Central America ◽  
Geographical Distribution ◽  
Early Spring ◽  
Field Conditions ◽  
Airborne Spores ◽  
Phellinus Igniarius ◽  
Late Autumn

Abstract A description is provided for Phellinus igniarius. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Common on the trunks of Salix and Populus, also recorded on Acer, Arbutus, Arctostaphylos, Betula, Carpinus, Castanopsis, Cornus, Erythropheum, Fagus, Fraxinus, Juglans, Ostrya, Pericopsis, Prunus, Pyrus, Quercus, Rhamnus and Ulmus. DISEASE: White heart rot. Causing a destructive decay of the general delignifying type. The decayed area becomes soft and white, bounded by conspicuous dark zones or black lines with an irregularly concentric arrangement. GEOGRAPHICAL DISTRIBUTION: Africa (Eritrea, Madagascar, Zambia); Asia (Japan, U.S.S.R.); Europe (Bulgaria, Czechoslovakia, Germany, Great Britain, Hungary, Netherlands, Norway, Rumania, Sweden); North America (Canada, U.S.A.); Central America (Nicaragua, Venezuela). TRANSMISSION: By airborne spores, which are continuously produced from early spring until late autumn when the temperature drops below 5°C (Riley, 1952). Spores remain viable for several months under field conditions (Iverson, 1968). Infection occurs mainly through branch wounds.

SOME SPECIES OF DIPTERA INHABITING OR FREQUENTING THE WHEAT FIELDS OF THE MIDDLE WEST

1900 ◽  
Vol 32 (7) ◽  
pp. 212-213
Author(s):  
F. M. Webster
Keyword(s):  
Early Spring ◽  
Late Autumn ◽  
The Dead ◽  
Middle West

The swarms of small Diptera that are to be found in the fields of fall wheat in Ohio, Indiana and Illinois, during late autumn and in early spring, seldom fail to attract the attention of the entomologist who has occasion to visit these fields at the above mentioned seasons. That some species are attracted to these fields as mere visitants is indicated by the accompanying list, but that many others breed there, either upon the living or the dead portions of the wheat plants, is as clearly apparent.

scholarly journals Evaluating strategies to improve glucosinolate concentration and root yield of field-grown horseradish in a Mediterranean environment: preliminary results

2016 ◽  
Vol 10 (1s) ◽  
pp. 65 ◽  
Author(s):  
Anna Rita Rivelli ◽  
Rosa Agneta ◽  
Christian Möllers ◽  
Susanna De Maria
Keyword(s):  
Horseradish Peroxidase ◽  
Bioactive Compounds ◽  
Dry Matter ◽  
Nutritional Value ◽  
Early Spring ◽  
Primary Role ◽  
Mediterranean Environment ◽  
Root Yield ◽  
Late Autumn ◽  
Glucosinolate Concentration

Horseradish is grown for its enlarged taproot that is widely used as a dish condiment and as a source of horseradish peroxidase. Nowadays, the species is gaining great interest due to the richness in bioactive compounds that besides providing a high nutritional value are tested for innovative applications in different fields. Nevertheless, the effect of crop management on root yield and glucosinolates (GLS) biosynthesis is poorly documented. Aim of this study was to evaluate the root yield and GLS concentration of two field-grown horseradish accessions (Cor and Mon) grown with nitrogen (N) alone and both N and sulphur (S) (-N-S, +N-S and +N+S treatments) and harvested at different times [late autumn (LA), 2011 and 2012, early spring (ES), 2012]. Yield increased throughout the harvests up to 48% on average of the fertilised treatments and 25% in the unfertilised control. Conversely, root GLS concentration significantly declined in the unfertilised control throughout the harvests [from 7.6 in LA_2011 to 1.43 μmol/g dry matter (DM) in LA_2012] while it highly increased in plants grown with N alone and with both N and S by 46 and 98%, respectively, from LA_2011 to ES_2012 (up to 11.9 and 21.1 μmol/g DM, respectively); then it drastically decreased by 80% on average, in the next harvest. Among individual GLS, the concentration of sinigrin and nasturtin similarly varied as effect of the analysed factors, showing the highest values in Cor accession. The data show that although the level of GLS is highly dependent on genotype, fertilisation and harvesting date may play a primary role in determining the yield and GLS concentration in horseradish root.

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