scholarly journals Dynamics of frost resistance in various provenances of Abies grandis Lindl.

2014 ◽  
Vol 67 (1) ◽  
pp. 51-58 ◽  
Author(s):  
Adam Dolnicki ◽  
Wojciech Kraj

The frost resistance of one year old needles and shoots of <em>Abies grandis</em> (seven provenances) and <em>Abies alba</em> (one provenance) was determined using Dexter's method since early autumn till late spring (September-May). Material was collected from trees over ten year old, planted in Beskid Sądecki Range near Krynica, 800 m above sea level. In this study it was found, that in early autumn (September) <em>A. grandis</em> develops weaker frost hardiness than <em>Abies alba</em>. In the late autumn and in winter, provenances coming from region II (according to Müller), and especially provenance 12016, are equal in respect to frost hardiness of shoots and needles to <em>Abies alba</em>. Among the provenances from Müller's region I exceptional frost hardiness is displayed by provenance 12005, which is also characterized by fast growth. In spring, <em>Abies alba</em> flushes earlier than <em>A. grandis</em>, which makes it more susceptible to late frosts.

1984 ◽  
Vol 35 (3) ◽  
pp. 307 ◽  
Author(s):  
TG Dix ◽  
A Ferguson

Major spawning by M. e. planulatus occurred in the late winter or early spring at Hinders Reef, Margate and Birchs Bay in 1980 and 1981. Spawning occurred also over the summer and early autumn although a major spawning was indicated during this period at only one site in one year. At the two sites where temperatures were recorded, the major spring spawning occurred at about or just above 10�C. Gonads built up reproductive condition during late autumn and winter at all sites in 1980 and 1981. Condition indices were highest at these times and fell when spring spawning occurred.


2005 ◽  
Vol 35 (11) ◽  
pp. 2539-2552 ◽  
Author(s):  
Jarosław Socha ◽  
Marian Kulej

This study compared the stem form of different provenances of Abies grandis Lindl. under the mountain conditions of Poland. Seven partial populations of this species, originating from two regions in its natural range, were tested. It was concluded that creating separate stem form models is an effective method for comparing stem forms, because the model curves for the groups under comparison are not affected by tree dimensions. The results of this study showed distinct variation in the tested populations of A. grandis in respect to stem form according to provenance (genotype). These differences are particularly evident between provenances from the different regions determined by Müller (K.M. Müller. 1935. Mitt. Deutcsh. Dendrol. Ges. 44: 54–123 and K.M. Müller. 1936. Mitt. Deutcsh. Dendrol. Ges. 47: 82–132). In general terms, trees representing provenances from region II are characterized by greater cylindricity in comparison with trees from region I. At equal DBH and height, the volume of trees from regions I was smaller than the volume of trees from region II by an average of approximately 7.6%.


The author adverts to a former paper “On the Meteorolog of the Deccan,” published in the Philosophical Transactions for 1835, and after referring to the conclusions at which he arrived in that communication, states that, in the discussion of the meteorological observations which form the subject of the present paper, and which were made over a very extended area, at different heights, some being hourly and running through several years at the same station, it is very satisfactory to find that they fully establish the accuracy of the former deductions. He remarks that, as some of the obser­vations now discussed were hourly records continued through con­siderable periods of time, an opportunity has been afforded of in­vestigating abnormal conditions, which the former limited number of diurnal observations did not permit; and gives the following review of what appears to be normal and abnormal conditions. The annual and daily range of the barometer diminishes from the sea-level up to the greatest height observed, 8640 feet at Dodabetta, from a mean annual and mean daily range at Madras of 0·735 and 0·122 respectively to 0·410 and 0·060 at Dodabetta;—the annual range would appear to increase, about and beyond the northern tropic, as the annual range at Calcutta (not by hourly observations) is 0·911; but the diurnal range is somewhat less (0·115) than at Madras. At no one of the places of observation, even taking the maximum pressure of one year with the minimum pressure of another year, does there appear to have been a range of pressure equivalent to an inch of mercury; nevertheless in the Cyclones, or rotatory storms, there occurs at times a range of pressure of nearly two inches of mercury within forty-eight hours; but it is shown from a compa­ rison of the simultaneous records on board ship, where these great depressions were noted, with the records at the observatories on shore, that the great depressions occurred within very limited areas.


1995 ◽  
Vol 25 (1) ◽  
pp. 18-28 ◽  
Author(s):  
B.J. Hawkins ◽  
M. Davradou ◽  
D. Pier ◽  
R. Shortt

One-year-old seedlings of western red cedar (Thujapiicata Donn ex D.Don) and Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) were grown for one season in five nutrient treatments with nitrogen (N) supplied in solution at rates of 20, 100, or 250 mg•L−1 and phosphorus (P) supplied at rates of 4, 20, or 60 mg•L−1. Growth, onset of dormancy, frost hardiness on six dates, and foliar nutrient concentrations in autumn and spring were measured. Midwinter rates of net photosynthesis and transpiration were measured at air temperatures of 4, 7, and 11 °C in seedlings from all nutrient treatments. Recovery of net photosynthesis and transpiration in whole seedlings from the three N treatments was assessed at intervals for 28 days after the seedlings were frozen to −5, −15, and −25°C. Foliar N content differed significantly among nutrient treatments and was positively correlated with supply. Mitotic activity ceased earliest in plants with low N supply. Douglas-fir seedlings in the low-N treatment also ceased height growth earliest. These differences in growth had no significant correlation with frost hardiness. No consistent differences in frost hardiness among nutrient treatments were observed. Higher rates of N and P supply resulted in higher rates of winter net photosynthesis. Net photosynthesis was reduced dramatically by night frost, with greater damage occurring at lower temperatures. Net photosynthesis recovery occurred most quickly in seedlings with the midrate of N and P supply.


Author(s):  
Hari Krishna ◽  
Peter D. Kemp ◽  
The Late Sally D. Newton

'Necton' sulla (Hedysarum coronarium L.) is a perennial forage legume with potential to provide high quality, non-bloating feed. This trial examined the effect of grazing intensity and frequency on sulla over one year. Annual dry matter yields ranged from 7.4 to 18.0 t/ha. There was no difference in the yield of hard and lax-grazed plots but grazing in late autumn significantly decreased plant density and yield. Keywords 'Necton', sulla, legume, grazing management


Author(s):  
Nikolay Stoenchev ◽  
Yana Hrischeva

Abstract The aim of the present article is to research the availability of rules in the change of the prices of the most spread flats in the neighbourhoods of Sofia. The results from a research in the change of the offered prices of the residential real estates by months for an annual period of time (from October 2016 to September 2017) have been presented. The presence of an uprising tendency for the bigger share of the neighbourhoods has been proven. For those of them where there is a tendency missing are calculated indices for seasonality by the method of the mean chronological value. Upcoming seasonal deviations of the mean monthly prices from the average annual by the separate types of flats (studios, one-bedroom and two-bedroom flats), whereas the highest values are registered in the summer and the early autumn - the months August and September, and the lowest in the late autumn - the months October and November. The most significant are the fluctuations in the variation of the prices in the studios, followed by the two-bedroom flats and one-bedroom flats. The results could be useful to some potential investors.


Parasitology ◽  
2000 ◽  
Vol 120 (3) ◽  
pp. 225-235 ◽  
Author(s):  
L. E. RODRIGUEZ ◽  
M. URQUIZA ◽  
M. OCAMPO ◽  
J. SUAREZ ◽  
H. CURTIDOR ◽  
...  

Solid experimental evidence indicates that EBA-175 is used as a ligand by the Plasmodium falciparum merozoite to bind to human RBC, via different binding processing fragments. Using synthetic peptides and specific receptor-ligand interaction methodology, we have identified 6 high-activity binding sequences from the EBA-175 CAMP strain; peptide 1758 (KSYGTPDNIDKNMSLIHKHN), located in the so-called region I for which no binding activity has been reported before, peptides 1779 (NIDRIYDKNLLMIKEHILAI) and 1783 (HRNKKNDKLYRDEWWKVIKK), located in region II, in a sub-region known as 5′ Cys F2, previously reported as being a binding region, and peptides 1814 (DRNSNTLHLKDYRNEENERH), 1815 (YTNQNINISQERDLQKHGFH) and 1818 (NNNFNNIPSRYNLYDKKLDL), in region III–V where antibodies inhibit merozoite invasion of erythrocytes. The affinity constants were between 60 and 180 nM and the critical amino acids involved in the binding were identified. The binding of these peptides to enzyme-treated RBC was analysed; binding of peptide 1814, located in the III–V region, was found to be sialic acid dependent. Some of these high binding peptides were able to inhibit in vitro merozoite invasion and to block the binding of recombinant RII-EBA to RBC. Several of these peptides are located in regions recognized by protective immune clusters of merozoites (ICMs) eluted antibodies.


1975 ◽  
Vol 53 (8) ◽  
pp. 1110-1115 ◽  
Author(s):  
D. H. Steele ◽  
V. J. Steele

Gammarus finmarchicus is an amphi-Atlantic species. In the western Atlantic it is found from the island of St. Pierre south to Long Island Sound. At St. Andrews, New Brunswick, 50% maturity occurs at 10.5 mm in the females. Reproduction is in progress throughout the year, but small females evidently are in a resting condition during September–October before breeding. The release of young by the population is greater in the spring, summer, and early autumn than it is in late autumn and winter. The young released in the spring and summer do not reproduce until the next year so that the life cycle is annual.


2020 ◽  
pp. 2150046
Author(s):  
Tianyang Liu ◽  
Xiaofei Wang ◽  
Congcong Li ◽  
Bowen Shen ◽  
Mingyan Yao ◽  
...  

[Formula: see text] (SLTO) ceramics ([Formula: see text] = 0.05, 0.10, 0.15) were prepared with giant dielectric constant by the traditional solid-state method at 1350[Formula: see text]C. The temperature dependence of the dielectric constant was obtained at the temperature ranging from 29[Formula: see text]C to 500[Formula: see text]C and the frequency ranging from 2 kHz to 2 MHz. Two sets of relaxation peaks appear in the low temperature (region I) and the high temperature (region II), respectively. For region I, we conclude that the relaxation behavior is related to the oxygen vacancy migration. For region II, the two relaxation processes are caused by grain boundary for high frequency and Sr or Ti defects at grain interior for low frequency. With the doping amount reaching 0.15, the relaxation peaks disappear and become a common phase transition because of the aggravation of lattice distortion. These possible physical mechanisms of two sets of relaxation peaks are briefly discussed.


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