Ograniczanie wyników

Czasopisma help
Autorzy help
Lata help
Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 36

Liczba wyników na stronie
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 2 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych:  arbuscular mycorrhizal fungi
help Sortuj według:

help Ogranicz wyniki do:
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 2 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
Mycorrhizal fungi greatly enhanced the ability of plants to take up phosphorus and other nutrients those are relatively immobile and exist in low concentration in the soil solution. Fungi can be important in the uptake of other nutrients by the host plant. Mycorrhizae establish symbiotic relationships with plants and play an essential role in plant growth, disease protection, and overall soil quality. Of the seven types of mycorrhizae described in current scientific literature (arbuscular, ecto, ectendo, arbutoid, monotropoid, ericoid and orchidaceous mycorrhizae), the arbuscular and ectomycorrhizae are the most abundant and widespread. This chapter presents an overview of current knowledge of mycorrhizal interactions, processes, and potential benefits to society. The molecular basis of nutrient exchange between arbuscular mycorrhizal (AM) fungi and host plants is presented; the role of AM fungi in disease protection, alleviation of heavy metal stress and increasing grain production. Most land plants form associations with mycorrhizal fungi. Mycorrhizas are mutualistic associations between fungi and plant roots. They are described as symbiotic because the fungus receives photo synthetically derived carbon compounds and the plant has increased access to mineral nutrients and sometimes water.
In December 1997 and June-July 2000, 49 and 113 rhizosphere soil and root mixtures were collected, respectively, to determine the occurrence of arbuscular mycorrhizal fungi (AMF) of the phylum Glomeromycota in different sites of Israel. Except for five samples taken from under cultivated plants, all the others came from under Ammophila arenaria and Oenothera drummondii colonizing sand dunes adjacent to the Mediterranean Sea. After a continuous cultivation of the mixtures in pot trap cultures with Plantago lanceolata as the plant host up to 2006 and their examination at least twice a year, spores of AMF were found in 41 and 103 cultures with the 1997 and 2000 soil and root mixtures, respectively. The spores represented 30 species and 8 undescribed morphotypes in 7 genera of the Glomeromycota. The AMF most frequently found in Israeli soils were Glomus aurantium and G. constrictum, followed by G. coronatum, G. gibbosum, an undescribed Glomus 178, and Scutellospora dipurpurescens. Up to 2001, 21 species of AMF were known to occur in Israel, and this paper increases this number to 33, of which 11 are new fungi for this country. Moreover, four species, G. aurantium, G. drummondii, G. walkeri and G. xanthium, were recently described as new for science based on spores isolated from Israeli soils. Additionally, the general distribution in the world of the formally described species found in Israel was presented.
Apple scar skin viroid (ASSVd) is a serious pathogen of apple fruits that results in severe loss in apple production. Up to nowadays, many ASSVd management options are applied to resist the disease, but the diserable resulits are not achieved. Therefore, this study was conducted in 2010–2012 at experimental field of Penglai City, Shandong Province, China (E 120°57’22’’, N 370°38’33’’) to investigate whether arbuscular mycorrhizal (AM) Glomus versiforme protects Red Fuji apple trees (Malus × domestica Borkh) against apple scar skin viroid. Red Fuji apple trees were inoculated with Glomus versiforme and then potential protection mechanism was explored and compared to noninoculated plants. The results showed that inoculation with Glomus versiforme significantly increased root length colonization rate and clearly decreased the percentage of disease severity of apple scar skin disease. Compared to non-inoculated plants, Glomus versiforme obviously enhanced total nitrogen and phosphorus concentrations in leaves. Root colonization by Glomus versiforme induced an increase in defense-related enzyme activities in fruits, such as the enhanced activities of catalase, ascorbate peroxidase, chitinase and glucanase. Significant differences in acid content of fruit and fruit yield were observed as apple roots were colonized by Glomus versiforme. It is therefore concluded that Glomus versiforme can be regarded as a biocontrol agent to protect apple trees against the infection with ASSVd.
Arbuscular mycorrhizal fungi (AMF) and dark septate endophyte (DSE) associations were studied in 36 medicinal plant species from 33 genera and 17 families, collected from the Botanical Garden of the Jagiellonian University in Kraków. Arbuscular mycorrhiza (AM) was found in 34 species (94%); 26 were of the Arum-type, 4 – Paris and 4 taxa revealed intermediate morpho­logy. The abundance of AMF hyphae in roots varied with particular species, ranging from 2.5% (Helianthus tuberosus) to 77.9% (Convallaria majalis). The mycelium of DSE was observed in 13 plant species (36%), however, the percentage of root colonization by these fungi was low. Spores of 7 AMF species (Glomeromycota) were isolated from trap cultures established from rhizosphere soils of the investigated plants: Archaeospora trappei (Archaeosporaceae), Glomus aureum, Glomus caledonium, Glomus claroideum, Glomus constrictum, Glomus mosseae, Glomus versiforme (Glomeraceae). Our results are the first detailed report of root endophyte associations of the plant species under study. Moreover, the mycorrhizal status of 14 plant species is reported for the first time.
The study was conducted in the Pomological Orchard and a greenhouse complex of the Research Institute of Horticulture in Skierniewice (RIH) in 2006-2008. Its aim was to identify arbuscular mycorrhizal fungi (AMF) present in the trap cultures con­taining rhizosphere soil and to determine mycorrhizal frequency (colonization) of AMF in the roots of apple trees 'Gold Milenium' and blackcurrant bushes 'Tiben'. The apple trees and blackcurrant bushes were mulched (with a peat substrate, bark, sawdust, manure, compost, or straw) and inoculated (the AMF inoculum was pro­duced by MYKOFLOR). Samples of the soil and roots were collected from under the apple trees and blackcurrant bushes in experimental combinations and in the control. In order to iden­tify the spores of arbuscular mycorrhizal fungi, trap cultures (with rhizosphere soil and sand) were set up with plantain (Plantago lanceolata L.). The spores were iso­lated from the trap cultures and microscopic specimens were prepared to identify the species of AMF, which were distinguished on the basis of their morphological fea­tures. Mycorrhizal frequency was determined in the specimens of apple and blackcur­rant roots dyed with aniline blue. Vol. 19(1)2011: 35-49 In total, eight species of AMF were identified in the trap cultures established with the soil samples taken from the root zone (containing rhizosphere soil) of apple trees 'Gold Milenium' and blackcurrant bushes 'Tiben': Glomus aggregatum, G. caledonium, G. claroideum G. constrictum, G. intraradices, G. macrocarpum, G. mosseae and Gigaspora margarita. In the trap cultures with the rhizosphere soil ofapple, the greatest number of species was found in the combinations with manure and the mycorrhizal inoculum (5 species), and compost (4 species). In the case of black­currant, the use of the mycorrhizal substrate and straw resulted in the largest number of AMF species (5 and 4, respectively). In the 2008 season, the highest mycorrhizal frequency in apple was obtained in the mycorrhized roots (44.4%), lower in the combinations with compost, sawdust, manure, bark, straw, and peat, and the lowest in the roots of NPK control plants (5.56%). The highest mycorrhizal frequency in the roots of blackcurrant bushes cv. 'Tiben' was recorded following the application of the mycorrhizal inoculum (12.22%), lower in the combinations with sawdust, compost, straw, peat, manure, and bark, and the lowest in the NPK control (1.67%).
A pot study was conducted to determine the effects of arbuscular mycorrhizal (AM) fungi (Glomus mosseae and Paraglomus occultum) and salt (NaCl) stress on growth, photosynthesis, root morphology and ionic balance of citrus (Citrus tangerine Hort. ex Tanaka) seedlings. Eighty-five-day-old seedlings were exposed to 100 mM NaCl for 60 days to induce salt stress. Mycorrhizal colonization of citrus seedlings was not affected by salinity when associated with P. occultum, but significantly decreased when with G. mosseae. Compared with the non-mycorrhizal controls, mycorrhizal seedlings generally had greater plant height, stem diameter, shoot, root and total plant biomass, photosynthetic rate, transpiration rate and stomatal conductance under the 0 and 100 mM NaCl stresses. Root length, root projected area and root surface area were also higher in the mycorrhizal than in the nonmycorrhizal seedlings, but higher root volume in seedlings with G. mosseae. Leaf Na⁺ concentrations were significantly decreased, but leaf K⁺ and Mg²⁺ concentrations and the K⁺/Na⁺ ratio were increased when seedlings with both G. mosseae and P. occultum. Under the salt stress, Na⁺ concentrations were increased but K⁺ concentrations decreased in the mycorrhizal seedlings. Under the salt stress, Ca²⁺ concentrations were increased in the seedlings with P. occultum or without AM fungi (AMF), but decreased with G. mosseae. Ratios of both Ca²⁺/Na⁺ and Mg²⁺/Na⁺ were also increased in seedlings with G. mosseae under the non-salinity stress, while only the Mg²⁺/ Na⁺ ratio was increased in seedlings with P. occultum under the salt stress. Our results suggested that salt tolerance of citrus seedlings could be enhanced by associated AMF with better plant growth, root morphology, photosynthesis and ionic balance.
Murraya koenigii L. (family: Rutaceae), commonly referred to as curry leaf, is a highly valued plant due to its aroma and medicinal features. Two dominant AM species Glomus mosseae and Acaulospora laevis were isolated from the rhizospheric soil of M. koenigii. A pot experiment was performed to verify the interactive potential of G. mosseae and A. laevis alone or in combination with Pseudomonas fluorescens on M. koenigii. Various morphological and biochemical parameters were measured after 120 days. Overall results suggest that all co-inoculation treatments showed beneficial effects on all the growth, physiological and oil content. The overall results demonstrate that the co-inoculation of bioinoculants, like P. fluorescens with AM fungi, promotes higher AM colonization and spore number enhancing the nutrient acquisition, especially phosphorus (P), improving the rhizospheric condition of soil.
The study investigated the effects of arbuscular mycorrhizal inocula Endorize- Mix, and Endomix, and mode of organic-mineral fertilization, on mycorrhizal coloni­zation and growth of Chamaecyparis lawsoniana 'Golden Wonder', Taxus x media 'Hicksii' and Thuja occidentals 'Smaragd' under a nursery-container production system. The fertilizing combination consisted of compost (0, 10 and 20% v/v) and Osmocote Standard 5-6M (1.5 and 3 g dm-3). The frequency of mycorrhiza in the root system, and growth of plants were evaluated. The use of Endorize-Mix resulted with mycorrhiza formation in all tested plants. The use of Endorize-Mix and Endomix in the container nursery production system allowed for the possibility of achieving well mycorrhized coniferous plants cultivated in pure peat-moss substrate and fertilized at the recommended rate of Osmocote Standard 5 -6M. The use of Endorize-Mix amelio­rated growth of C. lawsoniana and the use of Endomix ameliorated the growth of T. media after two years of cultivation.
The potential of mycorrhization of lettuce in hydroponic conditions was tested in a two-year experiment carried out in the autumn of 2011 and 2012 in an unheated foil tunnel. The experimental factors were as follows: inoculation of plants with arbuscular mycorrhizal fungi (AMF+ or AMF-), concentration of phosphorus in a nutrient solution (10 or 40 mg dm-3) and the type of substrate (rockwool or coconut coir). The inoculation of plants with arbuscular mycorrhizal fungi of the genus Glomus was performed twice, i.e. while sowing seeds and when planting lettuce plants into mats. The impact of the experimental factors on the degree of colonization of lettuce roots by AMF as well as the yield and nutritional status of plants, expressed as the content of macro- and micronutrients, was studied. The mycorrhizal frequency in roots inoculated with AMF reached 51.36%. The nutrient solution concentration of phosphorus and the type of substrate did not have any significant effect on the mycorrhizal frequency. There were no differences in the yield and content of macronutrients in lettuce leaves between plants inoculated and not inoculated with AMF (AMF+, AMF-). Likewise, there were no differences in the yield caused by different phosphorus levels in the nutrient solution or the types of substrate. Plants growing on rockwool accumulated significantly less P, Ca and Mg in comparison to plants growing on coconut coir. Regarding Ca, this effect was especially pronounced in plants receiving the nutrient solution with a higher concentration of P, i.e. 40 mg dm-3. Mycorrhiza had a significant effect on the content of Cu, Mn and Zn in lettuce leaves. Inoculated plants were characterized by a lower content of these micronutries compared to plants grown without AMF. With respect to Mn, this effect was particularly evident in plants grown on rockwool.
Physalis peruviana is one of the most promising tropical fruit plants because of its rapid growth, high yield, and nutritional quality. Th is study was designed to investigate plant development under heavy metal contamination (Cd, Pb) and responsiveness to arbuscular mycorrhizal fungi (AMF) colonization by Rhizophagus clarum and Claroideoglomus claroideum. Th e antioxidant capacity, total lipid content and fatty acid profi le in fruits, accumulation of Cd and Pb in diff erent plant parts, plant dry biomass, and mycorrhizal colonization were determined. As a result of inoculation, a considerable reduction in Cd and Pb in the fruits was observed, compared with non-inoculated plants. Th e fruit number and dry weight increased in plants associated with C. claroideum. Th ese plants also showed higher acid phosphatase activity, root protein accumulation and glomalin production. Th e type of antioxidant defense was AMF strain-dependent. Antioxidant activity and H2O2 neutralization were enzymatic rather than non-enzymatic processes in the fruits of C. claroideum plants compared with those forming an association with R. clarum. Mycorrhizal establishment changed the composition and concentration of fruits’ fatty acids. Th e ratio of unsaturated fatty acids was increased. With respect to the accumulation of bioactive compounds in golden berry the present fi ndings are important for obtaining the optimum benefi ts of mycorrhizal association under unfavorable conditions.
An experiment was carried out in a greenhouse of the Research Institute of Horticulture (RIH) to evaluate the effect of new organic fertilizers and amendments on root growth and mycorrhizal abundance and species richness in the rhizosphere of strawberry plants cv. 'Elsanta'. The plants were grown in rhizoboxes (sized 37 cm x 1.8 cm x 20 cm), filled with 1.85 kg of a podsolic soil collected from an uncultivated field of an experimental organic orchard of the RIH. The soil characteristics were: pH 5.5, organic matter content 1.5%, P content 51 mg P kg-1, K content 158 mg K kg- 1 . The plants were treated with different organic fertilizers and amendments: dry granulated bovine manure (Doktor O'grodnik), extract of vermicompost (Humus UP), extract of humates (Humus Active + Aktywit PM), plant extract (BioFeed Amin), extract from several seaweed species reinforced with humic and fulvic acids (BioFeed Quality), a consortium of beneficial soil organisms (Micosat), a stillage from yeast production (Vinassa) and a solution of titanium (Tytanit). Plants treated with BioFeed Amin, BioFeed Quality, Micosat, Vinassa and Tytanit received also half dose of dry manure. A standard NPK fertilization (NPK control) and a not fertilized control were also included. The following parameters were measured: root growth and morpho­logical parameters, number of arbuscular mycorrhizal fungi (AMF) spores, mycorrhizal frequency of AMF in the roots. The chemical composition of the applied products and of soil were also determined.
155 rhizosphere soil and root mixtures were collected from under Ammophila arenaria colonizing maritime dunes of the island Bornholm (Denmark) to determine arbuscular mycorrhizal fungi (AMF) of the phylum Glomeromycota co-existing with this plant. In the laboratory, each mixture was divided into two parts. One part was used to establish a pot culture with Plantago lanceolata as the host plant to initiate sporulation of fungi that had not produced spores in field conditions. In the second part, the numerical and species composition of the spore populations of AMF sporulating in the field was determined. Spores of AMF were found in 70 fieldcollected samples and 134 trap cultures. They represented 26 species and six undescribed morphotypes in six genera of the Glomeromycota. Of them, 20 species and three morphotypes in five genera occurred in the field, and 16 species and three morphotypes in five genera were found in trap cultures. The fungi most frequently revealed were members of the genus Glomus; a total of 17 species and six morphotypes of this genus were recognized. Considering the occurrence of spores in both field samples and trap cultures, the fungi most frequently co-occurring with roots of A. arenaria growing in the dunes of Bornholm were G. irregulare (present in 73.6% of samples), followed by Scutellospora dipurpurescens (19.4%) and Archaeospora trappei (10.3%). However, Glomus irregulare mainly sporulated in trap cultures; spores of this fungus were found in only 0.6% of field samples. Other relatively frequently found species were G. aggregatum (9.0%), G. eburneum (7.1%), Paraglomus laccatum (5.2%), and S. armeniaca (6.5%). The species most abundantly sporulating in the field were G. aggregatum (produced 28.36% of all spores isolated), G. badium (11.00%), and S. dipurpurescens (21.55%).
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 2 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.