scholarly journals Substrate specificity of glucokinase and fructokinase of several conifer species

2014 ◽  
Vol 71 (2) ◽  
pp. 125-127
Author(s):  
Fritz Bergmanni ◽  
Leon Mejnartowicz

Annual plant species were found to have several distinct classes of hexokinases which are specific for different hexoses, such as glucose, fructose and mannose. In conifers one isozyme of hexokinase could be found in genetic studies if only glucose was employed as substrate. If fructose was substituted for glucose, another isozyme zone different from the common hexokinase could be observed in zymograms of extracts from seed tissues of Norway spruce, Scots pine and silver fir. Hence these three conifer species possess at least two different hexokinases, glucokinase and fructokinase.

1977 ◽  
Vol 55 (6) ◽  
pp. 711-717 ◽  
Author(s):  
L. Mejnartowicz ◽  
F. Bergmann

Using techniques of starch gel electrophoresis, isoenzymes of ribonuclease 11 (RNase, EC 3.1.4.23) and phosphodiesterase I (PDase, EC 3.1.4.1) could be identified in endosperm tissue from dry seeds of three conifer species: Norway spruce (Picea abies). Scots pine (Pinus silvestris), and Douglas fir (Pseudotsuga menziesii). The RNase patterns mostly exhibited a relatively great number of isoenzyme bands as well as a considerable tree-to-tree variation, whereas the PDase system revealed only one enzyme zone in each of the three seed species. Furthermore, an isoenzyme variation within the PDase zones appeared to be very infrequent and could only be detected in Norway spruce and Douglas fir. However, the isoenzyme patterns of RNase as well as PDase showed significant differences between the conifer species. The genetic basis of the intraspecific isoenzyme variations could be easily analyzed, since the test material (seed endosperm) represented haploid tissues resulting from macrogametophytes after fertilization. Hence, it was possible to identify three polymorphic RNase gene loci in Douglas fir seeds, two in Scots pine seeds, and one in Norway spruce seeds. The PDase zone in each conifer species was controlled by one gene locus which revealed allelic forms only in Norway spruce and Douglas fir seeds.


Oecologia ◽  
2014 ◽  
Vol 176 (1) ◽  
pp. 95-106 ◽  
Author(s):  
Annamária Fenesi ◽  
Andrew R. Dyer ◽  
Júliánna Geréd ◽  
Dorottya Sándor ◽  
Eszter Ruprecht

2009 ◽  
Vol 33 (-1) ◽  
pp. 49-57 ◽  
Author(s):  
Edward Feliksik ◽  
Sławomir Wilczyński

The Effect of Climate on Tree-Ring Chronologies of Native and Nonnative Tree Species Growing Under Homogenous Site ConditionsDendroclimatic studies were carried out in the experimental stands composed of many tree species situated in the Polish part of the Baltic sea-coast. Increment cores were taken from a 100-years old trees of 2 native species: Norway spruce (Picea abies (L.) Karst.), and Scots pine (Pinus sylvestrisL.) and 3 nonnative species: Douglas fir (Pseudotsuga menziesii(Mirb.) Franco), Sitka spruce (Picea sitchensis(Bong.) Carr.) and Silver fir (Abies albaMill.). Thirty trees of each species were cored. The relationships between the diameter increment and the thermal and pluvial conditions during the period from 1925 to 2005 were analyzed on the basis of standardized tree-ring chronologies and climatic data. It was found that precipitation and temperature of the growing season and months preceding that season affected the annual diameter increment of all investigated tree species. The current year winter and early spring temperatures as well as February and August precipitation had a similar effect on the variation of diameter increment of trees. On the other hand thermal and pluvial conditions of the current year June differentiated the increment rhythm of individual species. A very strong negative effect on diameter growth of trees was observed in the case of winter and early spring frosts. Norway spruce turned out to be a species most resistant to low temperatures. The investigated tree species, especially Norway spruce, was susceptible to water deficiency in the soil during spring and summer. In the case of Scots pine a high precipitation in June stimulated its growth. The diameter increments of Douglas fir, Sitka spruce, Scots pine, and Silver fir were more strongly connected with air temperature than with precipitation. So called all-species chronology of tree-ring width, constructed during this study, permitted to verify the factors having a similar effect on growth response of the investigated tree species. It reflected the mutual characteristics of diameter increments of trees of various species.


Ecology ◽  
1973 ◽  
Vol 54 (4) ◽  
pp. 723-740 ◽  
Author(s):  
Rebecca R. Sharitz ◽  
J. Frank McCormick

1997 ◽  
Vol 45 (4) ◽  
pp. 317-327 ◽  
Author(s):  
Yitzchak Gutterman ◽  
Shachar Shem-Tov

Groups of dry seeds of four annual plant species which occur in the Negev highlands were placed on a natural, dry or wet loess soil crust surface near Sede Boker on the Zin plateau during the autumn before the first rains, and on the first day with rain (1.15 mm). Ant nests ofMessor rugosuswere 8 to 14m from the experimental plot. The length of time it took these ants to collect the free or adhered seeds was observed. When the mucilaginous ombrohydrochoric seeds ofAnastatatica hierochuntica, Plantago coronopus, andCarrichtera annuaadhere to wet soil that remains moist, most of the seeds may have time to germinate in proper conditions before they are collected by ants. However, all but 5% of theReboudia pinnataseeds were collected within 2 h. The adhered seeds that had been moistened by wet soil crust and then dried, were collected by ants, in most cases, faster than when seeds and soil remained moist. Within 2 h none of the dry and free seeds situated on the dry soil surface remained. The first free seeds were collected after 7 min. Findings are discussed together with the mechanisms and strategies involved in seed dispersal by rain and germination of these plant species.


2019 ◽  
Vol 25 (1) ◽  
pp. 2-9
Author(s):  
Ana Brglez ◽  
Nikica Ogris

Species of the genus Armillaria and Heterobasidion are among the most common causes of stem and root rot in Slovenia. Armillaria spp. infects deciduous and coniferous trees, while Heterobasidion spp. mainly threatens Norway spruce (Picea abies), pines (Pinus spp.), and silver fir (Abies alba). On the basis of the data about the sanitary felling of infected trees, we estimated the current state and calculated the proportions represented in total felling, total sanitary felling, total sanitary felling due to diseases, in wood stock, and in increments from 2013 to 2017. Since 2014, there has been a constant increase in the sanitary felling of deciduous and coniferous trees due to infections with Armillaria spp. In 2017, 32,849 m3 of timber were harvested due to Armillaria spp. Given the present situation, we assume that the amount of sanitary felling will continue to increase, but it will not account for large shares in wood stock or increment (< 1 %). In 2017, sanitary felling of infected conifers represented 27.6 % of all sanitary felling due to diseases. In the case of deciduous trees, the share was lower, i.e. 7.1 %. Armillaria spp. was the main cause of sanitary felling due to disease (51.9 %) in the Postojna forest management unit (FMU), while elsewhere shares of up to 10 % were recorded. With Heterobasidion spp., the amount of felling is decreasing over the years. In 2017, 33,922 m3 of wood, accounting for 15.7 % of the total sanitary felling due to disease, were felled due to Heterobasidion spp. A comparison of the felling of Norway spruce, silver fir, and Scots pine due to Heterobasidion spp. shows the different proportions of felling within the total sanitary felling due to the diseases. In Norway spruce, it is on average 79.5 %, in silver fir 12.9 %, and in Scots pine 34.3 %. We assume that the volume of timber harvested due to Heterobasidion spp. will gradually decrease over the years due to the lower wood stocks of Norway spruce, which has recently been hit by numerous natural disasters and infestation of bark beetles. However, the incidence will be higher due to climate change affects.


Weed Science ◽  
1974 ◽  
Vol 22 (2) ◽  
pp. 185-187 ◽  
Author(s):  
Raymond A. Evans ◽  
James A. Young ◽  
Burgess L. Kay

Three annual plant species — erect plantain (Plantago erectaMorris), common chickweed [Stellaria media(L.) Cyrill.], and silver hairgrass (Aira caryophylleaL.)—are commonly found and may dominate a unique flora on areas sprayed with paraquat (1,1′-dimethyl-4,4′-bipyridinium ion) in cismontane rangelands of California. The basis of this phenomenon is shown to be temperature-related germination requirements, novel seed characteristics, and lack of competition.


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