The alleviation of reforestation challenges by beneficial soil microorganisms

Surface mining causes major destruction of natural landscapes and ecosystems. The most fertile, surface soil layer is lost permanently, together with vegetation, wildlife, and micro flora. Post-mining areas are characterized with diverse edaphic, topographic, hydrographic conditions, which complicate land restoration. Successful establishment of forest ecosystems on such land depends mostly on selection of tree species. The chosen plants must be capable of tolerating a wide range of acidity, fertility, moisture, and have potential to ameliorate such substrates for more demanding species. But, reforestation of heavily damaged ecosystems, such as post-mining areas, demands a new approach in seedlings production. This new approach takes into account specific requirements of habitat and integrates them into “targeted production of planting materialâ€. A good strategy for successful reforestation of post-mining areas is the input of organic matter (compost, mulch). Also, current knowledge and experiences emphasize the potential of beneficial microorganisms such as, mycorrhizal fungi (MF) and plant growth promoting rhizobacteria (PGPR). The majority of studies that deal with beneficial interactions between trees and microorganisms are focused on the mycorrhiza, while plant growth promoting rhizobacteria are less present in silviculture. In this study, the focus is on the reforestation challenges of two mining basins, Majdanpek and Kolubara and suggests beneficial microorganisms as potential solution. The study presents results of several years’ researches on plant response to the presence of mycorrhizal fungi and PGPR. The substrates used for plant growth were Majdanpek and Kolubara mine deposals. Mycorrhizal seedlings were grown in Majdanpek mine deposal, and at the end of the experiment they had 30% higher biomass in comparison to control (seedlings without mycorrhiza). Seedlings linked with fungi had a higher survival rate. Deposals from Kolubara Mining Basin were used as a substrate for seedlings inoculated with PGPR. In the first experiment, Scots pine and Norway spruce were inoculated with Azotobacter chroococcum, Bacillus megaterium, B. circulans, B. licheniformis, B. pumilus, B. amyloliquefaciens. Inoculation resulted with higher biomass production (Scots pine 43%, Norway spruce 34%). Similar results were obtained in the second experiment where Scots pine and black locust were inoculated with Bacillus licheniformis, Aeromonas hydrophila, Pseudomonas putida and Burkholderia cepacia. Both species had higher biomass (around 20%) in comparison to un-inoculated control. The results confirmed the fact that early establishment and successful growth of vegetation on devastated areas depends on the presence and activity of soil microbes. Microorganisms as a “nature’s solution†pose the potential to alleviate reforestation challenges of anthropogenic devastated landscapes. Their presence and activity is crucial for ecosystem stability. In areas with compromised balance, their introduction is justified action for achieving the goal of long term ecosystem sustainability

Use of overburden waste for London plane (Platanus x acerifolia) growth: the role of plant growth promoting microbial consortia

Overburden waste dumps represent a huge threat to environmental quality. The reduction of their negative impact can be achieved by vegetation cover establishment. Usually, this action is complicated due to site-specific characteristics, such as nutrient deficiency, elevated metal concentration, low pH value, lack of moisture and lack of organic matter. Establishment of vegetation can be facilitated by inoculation with plant growth promoting bacteria (PGPB) which improve the physicochemical and biological properties of degraded substrates and make them more hospitable for plants. In this study we selected several strains based on the ability to produce ammonia, indole-3-acetic acid, siderophores and lytic enzymes, and to solubilize inorganic phosphates. This selection resulted in microbial consortia consisting of Serratia liquefaciens Z-I ARV, Ensifer adhaerens 10_ARV, Bacillus amyloliquefaciens D5 ARV and Pseudomonas putida P1 ARV. The effects of PGPB consortia on one-year-old London plane (Platanus x acerifolia [Aiton] Willd.) seedlings replanted into overburden waste from Kolubara Mine Basin were examined. After seven months, inoculated seedlings were 32% higher with 45% wider root collar diameter and over 80% higher total dry biomass compared to uninoculated seedlings grown in Kolubara's overburden. Inoculation resulted in higher amounts of total soluble proteins, higher chlorophyll and epidermal flavonoids content and higher total antioxidative capacity in the leaves. This study represents a successful search for effective PGPB strains and shows that microbial consortia have an important role in enhancing the growth of seedlings in nutrient deficient and degraded substrates such as overburden waste from open-pit coal mines. Positive response of London plane seedlings suggest that inoculation may help widening the opus of species for reforestation of post mining areas and speed up natural succession processes and recovery of degraded landscapes

Microbial consortium in in situ remediation of DDT residues-affected soil

Organochlorinated pesticides (OCPs), such as DDT are characterized as highly persistent and mobile in environment, with high bioaccumulation capacity. The use of those chemicals has been banned in the United States and Europe for decades (Tsai, 2014). Despite this, OCPs-affected ecosystems are detected in several countries, even in the XXI century. Malusa et al. (2020) reported the presence of DDT in more than 80% of soil samples originating from organic farms in Poland. The objective was to determine the impact of microbial consortium on DDT biodegradation in soil. BacFung microbial consortium consisting of Bacillus sp., Pseudomonas sp., Azotobacter sp. and Trichoderma sp. was used for soil inoculation. Soil conditions were improved by grass sowing. The research was conducted at a playground in Tivat (Montenegro), and the size of the total examined area was 3,000 m2 divided into 13 sub-units. The concentration of DDT and its metabolites (DDE - dichlorodiphenyldichloroethylene and DDD - dichlorodiphenyldichloroethane) was measured by GC/MS technique. The initial DDT concentration in soil sub-units varied from 0.005 to 20.5 mg/kg. The sum of DDT+DDD+DDE (ΣDDT ) concentrations varied from 0.024 to 22.7 mg/kg (average concentration was 1.69 mg/kg). After the application of BacFung microbial consortium, the decline of DDT amount in soil sub-units was observed (from 0.005 to 0.057 mg/kg); ΣDDT was 0.020 to 0.2 mg/kg (average value 0.055 mg/kg). The accumulation of DDD and DDE, as initial degradation products of DDT, was observed. These results showed that microbial consortium BacFung can be used in removal of DDT from polluted environment

Ispitivanje nekih fizioloških osobina mikorizne gljive Amanita muscaria (Linn. Ex fries)

This paper presents laboratory results of the research on certain physiologic properties of Amanita muscaria (Linn. ex Fries). The MEA, PDA and modified MEA media were used for testing the influences of different media on the growth of mycelia. In order to test the influences of fungicides and heavy metals in medium on the fungus growth we have set the experiments where nutrient media was enriched by fungicides Befungin and Captan FL, or solutions of heavy metals Pb, Cu, Cd, and Zn in three different concentrations (3ppm, 33ppm, and 100ppm). .U radu su prezentovani rezultati laboratorijskih ispitivanja nekih fizioloških osobina gljive Amanita muscaria (Linn. Ex Fries). Za ispitivanje uticaja različitih podloga na porast micelije korišćene su MEA, PDA i modifikovana MEA podloga. Da bi se ispitalo kakav uticaj ima prisustvo fungicida i teških metala u podlozi na rast ove gljive postavljeni su ogledi u kojima je hranljivoj podlozi dodati fungicidi Benfungin i Kaptan FL ili rastvori teških metala Pb, Cu, Cd i Zn u tri različite koncentracije (3 ppm, 33 ppm i 100 ppm)

Konzorcijum bakterija stimulatora biljnog rasta u revegetaciji deposola

Суштина техничког решења огледа се у повећању ефикасности ревегетације депосола дрвенастим врстама. Техничким решењем је дизајниран нови производ који ће побољшати снабдевање биљака нутријентима (N, P, Fe), регулисати хормонски статус, повећати отпорност на патогене микроорганизме и на тај начин стимулацијом раста и ублажавањем ефекта стреса допринети повећању успешности рекултивације. Техничким решењем дефинисан је микробни конзорцијум бактерија стимулатора биљног раста који ће допринети успостављању вегетацијског покривача на депосолу и повећати плодност, стабилност и одрживост земљишног екосистема

Seed germination and seedling growth of Ailanthus altissima, Acer negundo, Pinus silvestris, and Picea abies in elevated concentrations of Zn, Pb and Cd under laboratory conditions

Phytoremediation and phytostabilisation of abandon open miming sites is very important process for rehabilitation of land and watercourses to an acceptable standard. Seed germination and seedling establishment in post-mining sites is of great importance for early succession and restoration patterns. Several of early colonizers are tree species, but they could be very important elements of early successions and influence dynamic of early revegetation in disturbed areas. Spontaneous colonization of mining spoils is difficult due to extremely difficult condition such as extremely low or high pH, mineral soil, low water capacity and nutrient deficiency. Besides this, high concentration and solubility of toxic metals in mining areas could be the most limiting factor for plant establishment. We analyzed parameters of seed germination and seedling growth of early successional tree species (two broad leaf and two pine species species against): Ailanthus altissima, Acer negundo, Pinus silvestris, Picea abies in several experimental systems with three different concentration of toxic metals (Pb, Cd, Zn) to assess influence of metal toxicity in early phase of plant development. Lead in applied concentrations (25, 50 and 100 mu M) did not affect significantly the seed germination percentage in Ailanthus altissima and Acer negundo while cadmium in highest concentrations (100 mu M) caused reduction of the germination percentage, germination index and vigor index in both species. Analysis of the parameters of early seedling development indicates the most pronounced toxic effects of cadmium. In Ailanthus altissima Zn treatments caused significant inhibition of shoot growth and repress development of assimilating organs in concentrations of 25, 100 and 250 mu M. In concentration of 25 mu M Zn caused an inhibition of the root growth. The spruce and Scot pine seeds which were developed on substrates with addition of heavy metals solutions showed significant tolerance to presence of all metals, but percentage of germinating seeds depended on the type of metal and its concentration. The seed of P. abies demonstrated higher tolerance to presence of heavy metals in lower concentrations, then seed of Pinus sylvestris and germinated in all variants. In the conditions of highest concentrations, the seeds of both species did not sprout regardless of the type of metal. The P. abies seedlings were very tolerant to the presence of all metals. The highest concentrations of cadmium had a significant influence on the decrease of the number of the seedlings which survived, as well as on the decrease of biomass in comparison to lead. Zinc had the least adverse effect on the growth and survival of seedlings. P. sylvestris seedlings did not exhibit the same tolerance for the presence of heavy metals

Same physiological characteristics of the three ectomycorrhizal fungi from Suillus genus

The aim of this paper is to present the results of the study of the same physiological characteristics of the three species of ectomycorrhizal fungi from Suillus genus (S. luteus (L. ex Fr.) S.F.Gray, S. bovinus (Fr.) O.Kuntze and S. granulatus (L. ex Fr.) O. Kuntze. S. granulatus is an excellent edible mushroom. S. luteus and S. bovinus are both edible but they are both of an inferior quality. Three different media (Melin-Norkans, MMN, Potate Dextrose Agar, PDA and Malt Extract Agar, MEA) were used for the study of the influence of the type of medium on the rate of growth and morphological shape of mycelium of fungi. The interaction between mycorrhizal fungi was examined in the laboratory conditions by the "mixed cultures". The assessment of the interaction between certain mycorrhizal species and the inhibitions of growth was determined as the ratio between their growth in the mixed culture and the controlling isolate growth on the nutritive medi

Influence of Heavy Metals on Seed Germination and Growth of Picea abies L. Karst

This paper presents the influence of heavy metals on the process of seed germination and the survival rate of Picea abies L. Karst spruce seedlings. The experiments were conducted in laboratory conditions by adding solutions of compounds of zinc, copper, lead, and cadmium at three different concentrations (3 ppm, 33 ppm, and 100 ppm) to the media. The observed heavy metals affected the germination of the spruce seeds in different ways. Although the seed was tolerant to the presence of all metals, the percentage of germinated seeds depended on the type of metal and its concentration. The lower concentrations of the heavy metals (3 and 33 ppm) partially inhibited seed germination, and the highest concentrations (100 ppm) of all metals caused total inhibition. The P. abies L. Karst seedlings were very tolerant to the presence of all metals. The highest concentrations of cadmium and copper had a significant influence on the decrease of the number of the seedlings that survived, as well as on the decrease of biomass in comparison with lead. Zinc had the least adverse effect on the growth and survival of seedlings