scholarly journals Generative reproduction of Vaccinium myrtillus in laboratory conditions and the influence of zinc-smelter emissions on it

2014 ◽  
Vol 50 (4) ◽  
pp. 663-672 ◽  
Author(s):  
Zuzanna Czuchajowska ◽  
Teresa Strączek

The germination of <em>Vaccinium myrtillus</em> seeds and the development of the seedlings in laboratory conditions are described. The dynamics, the power of germinaltion and Pieper coefficients for the seeds were strongly influenced by the intensity of zinc-,smelter pollution of the forest stand from which they originated. The rates of survival were also estimated for seedlings transferred from filter-;paper into polluted and unpolluted samples of soil and litter. The differences noticed in the latter parameter point to the possibility of formation in the polluted stand of ecotypes more resistant to the influence of pollution than the original ones.

Ecology ◽  
1975 ◽  
Vol 56 (1) ◽  
pp. 78-91 ◽  
Author(s):  
Marilyn J. Jordan

2018 ◽  
Vol 21 (2) ◽  
pp. 42-47 ◽  
Author(s):  
Mahmoud. A. Ghayyad

Abstract Seeds of Prunus species do not germinate as a result of different mechanisms of dormancy such as physiological, physical and/or chemical ones. This study was carried out in order to determine the effects of three concentrations of Gibberellic acid (GA3) 1, 3, and 5 mg.L−1 and low temperature at 5 °C on germination and on the length of isolated embryos from cotyledons of almond, apricot, plum, peach, mahaleb and sweet cherry on top of filter paper under laboratory conditions. The highest germination percentage (96.67%) was at 1 mg.L−1 GA3 without cold treatment or 3 mg.L−1 GA3 + cold treatment in almond, the highest length of embryos (15.47 mm) was also in almond at 1 mg.L−1 GA3 without cold treatment. Embryos of mahaleb and sweet cherry germinated at low germination percentages of 31.16%, 33.33% respectively at 3 mg.L−1 GA3 + cold treatment. It was concluded that embryos of almond, apricot, plum and peach were germinated successfully on top of filter paper under laboratory conditions and GA3 increased significantly the germination percentages of the isolated embryos either after cold treatment or without compared with controls. A strong positive correlation was found between seed germination without testa, embryos germination and final embryos length simultaneously.


2012 ◽  
pp. 111-122
Author(s):  
Vesna Golubović-Ćurguz ◽  
Katarina Mladenović ◽  
Biljana Nikolić ◽  
Snežana Rajković

Approximately 100 semi-ripe cones were harvested from a young forest culture of Pinus wallichiana grown on loamy deposol. Opening of cone scales and dropping of seed grains were induced under laboratory conditions. The number of damaged seeds and the type of damage, as well as the total and average number of seeds per cone, were determined on the population and individual levels. The intensity of damage was expressed in percentages. The analyses for determination of the present fungi and the intensity of their attack were conducted by placing the seeds onto a nutritious MEA bed and moist filter paper in Petri dishes. In order to establish the presence of insects, cones with visible damage were collected in the field. These cones were then examined in the laboratory and placed into photoeclectore for further growing.


1975 ◽  
Vol 21 (11) ◽  
pp. 1855-1865 ◽  
Author(s):  
Marilyn J. Jordan ◽  
Mary P. Lechevalier

Within 2 km of a zinc (Zn) smelter in Palmerton, Pennsylvania, near the Lehigh Water Gap, up to 13.5% Zn by weight has been measured in the O2 horizon of the soil, and up to 8% Zn in the A1 horizon. The total numbers of bacteria, actinomycetes, and fungi (measured by dilution plate counts) were greatly reduced in the most severely Zn-contaminated soils compared with control soils. The reduction of microbial populations may be a partial cause of the decreased rate of litter decomposition at Lehigh Gap.Growth of most bacteria from control sites was reduced by 100 to 200 μM Zn, most actinomycetes by 100 μM Zn, and most fungi by 100 to 1000 μM Zn in thin-Pablum extract agar (TPab). All the tested actinomycetes and non-spore-forming bacteria isolated from Zn-contaminated Lehigh Gap soils were Zn-tolerant, growing normally in media containing 600-2000 μM Zn. Most fungi, regardless of source, were capable of at least 50% of normal growth at 700 μM Zn. Zinc-tolerant bacteria, actinomycetes, and fungi were readily isolated from low-Zn soils, suggesting that selection for Zn tolerance may proceed rapidly.Acidophilic Mortierella species have been selectively eliminated near the smelter, apparently because of elevated soil pH. Peyronellaea glomerata (Corda) Goidanich and Coniothyrium spp. were found only in the high-Zn soils.


2014 ◽  
Vol 75 (3) ◽  
pp. 291-300 ◽  
Author(s):  
Anna Klamerus-Iwan

Abstract The subject of the study is the process of interception by plants defined as the process of retaining rainfall water on plant surface, counting retention by individual plant parts or the vegetation cover as the whole. In the quantitative approach, interception capability of plants may be compared to a reservoir, the capacity of which is determined mostly by the surface of plants. Among many approaches to describe interception processes, a lot of attention has been focused on research concerning the forest vegetation with reference to atmosphere - forest stand - soil balance. Hence, in the present paper interception issues are addressed in view of forest ecosystems. The emphasis is also put on the methods and results of studies carried out under laboratory conditions. Up-to-date literature on interception is abundant. The authors tackling this issue regularly define their own variable and complex sets of terms. This paper is an attempt to review and organise knowledge presented in existing literature on the subject.


Author(s):  
D. Sigareva ◽  
V. Kharchenko

Goal. To identify the effectiveness of entomopathogenic nematodes (Steinernema feltiae isolate with a biological product «Entonem» ™ Copert) on the larvae and adults of different insect pests at various ways of their infection, and to explore the possibility of generating a significant amount of the invasive larvae of entomopathogenic nematodes (EPN). Research methods. The material for our study is the 7 types of test insects: larvae of the large and the small wax moth, castaneum flour, gyroscope, common cabbage butterfly, Kovalik pilosula, as well as the may beetle, which was used stage larvae, as well as individuals of adult beetles (imago). All the studied insects infected with EPN (pathogen — Steinernema feltiae with biopreparation «Entonem» (™Koppert)) in the laboratory on filter paper or in sterile soil. Recorded date of infection and death of insects and counted the number of allocated of each type of insect infective larvae of nematodes. Estimated duration of migration and reproductive potential of different test insects. Results. The use of different methods of infection (dry contact parasite and insect hosts on filter paper or by making a dose in sterile soil, which was placed insect-host) at a dose of 50 larvae per one insect, showed that in half of the cases a significant difference between them is not detected. However, castaneum flour, Kovalik pilosula and ordinary spinning top, the best was the method of contamination in the Petri dishes, and adults of the may beetle — in groundwater samples. The duration of the process of migration of larvae of the entomopathogenic nematodes from the cadavers of insect hosts ranged from 27—51 day and were more dependent on the insect host than from its method of infection. A short period of migration of the larvae of large and small wax moth (27—36 days), long (35—45) from larvae of a top common and castaneum flour, the longest period of time (48—51 hours) — larvae of cabbage butterflies and a beetle may. Performance in relation to the amount of the newly formed infective larvae determines the insect host. Among the investigated 7-insects-the home of highest performance was observed in the may beetle (115980—120060 larvae) and the cabbage (93440—97880 larvae). Less productive was the great wax moth, the flour castaneum and the grasshopper pelousy (respectively 26880 ± 420; 34500 ± 430; 32400 ± 673).Less productive are the common top, the May beetle (imago) and the small wax moth, in which from 15640 to 26880 invasive larvae were formed. Findings. In laboratory conditions, without significant material costs, you can get a sufficient number of entomopathogenic nematodes. The method of directly introducing entomopathogenic nematodes onto test insects in Petri dishes proved to be the best compared to soil invasion. The duration and volume of migration of larvae of entomopathogenic nematodes is determined mainly by the species of host insects. The shortest migration period was recorded in wax moth larvae (small and large), significantly longer (almost 1.5 times) in the larvae of May beetle and cabbage. The most productive in relation to juvenile larvae of EPN were the cabbage and the larvae of the May beetle, and the least productive ones were the common top, May beetle (imago) and small wax moth.


Author(s):  
Sabrina Chergui ◽  
Khadidja Boudjemaa ◽  
Abdelmadjid Benzehra ◽  
Ismail Karaca

Abstract Background The Mediterranean fruit fly, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), is the major insect pest of fruit production worldwide. Chemical control of this pest has induced the selection of resistant medflies populations and negative environmental impact. In addition, the use of pesticides has become an obstacle to the fresh agricultural products exported to many countries that restrict pesticides residues. The aim of this study was to propose alternatives based on the use of microbiological products for the control of C. capitata. Main body The pathogenicity of the Turkish isolate Beauveria bassiana BMAUM M6-4 was evaluated against immature stages and adult of C. capitata under laboratory conditions at a concentration of 107 conidia/ml via different routes of exposure. Conidial treatment was applied by spraying soil and filter paper against 3rd instar larvae and pupae. In contrast, the treatment was administered to adult males and females by contact and ingestion. The percentage of mortality was recorded on the 3rd, 7th, 12th and 15th day after inoculation. Obtained results showed that B. bassiana was very effective against the adult’s fly, where males were more susceptible than females in both treatments (contact and ingestion). This isolate was tested against 3rd instar larvae. It achieved an infection rate of 33.33 and 43.5% of the larvae treated on filter paper and in the soil, respectively. Application of conidial preparations to soil reduced insect emergence and CAN represent a promising strategy for fruit fly integrated management (57.33 and 56.66% emergence from the treatments in soil and filter paper). Conclusion Entomopathogenic fungi are promising as a biocontrol agent that can be used under different modes of ground application against larvae, prepupae and pupae, and/or as a bait spraying or contact against adults.


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