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Soil microorganisms, which are usually found in plant rhizosphere, have a wide spectrum of beneficial effects on the promotion of plant growth. The most comprehensively studied bacteria with these effects belong to the Bacillus genus. In this study, seven Bacillus isolates from Medicago sativa rhizosphere soils were isolated. Plant growth promoting characteristics of these isolates, such as production of indole-3aceticacid, siderophores and hydrogen cyanide were tested. The induction of wheat (Triticum aestivum) and barley (Hordeum jubatum) seed germination was evaluated in vitro. Isolate BMG2 produced the highest indole-3-aceticacid of 24.89 µg/mL. The length of roots of barley increased up to 60%, while the length of shoots of barley increased 2.23 times afterapplying isolatesPAZE-6 and BMG1, respectively. In addition, isolates BMG1, BMG2 and PAZE-6 improved germination of both types of seeds and showed ability to produce useful substances such as siderophores and indole-3-acetic acid. Further, these isolates could be used in the production of liquid crop additives that can improve the total yield of cultivated plants, especially barley., Zemljišne bakterije iz rizosfere korena biljaka najčešće imaju širok spektar pozitivnog dejstva na biljke I mogu poboljšati njhiov rast. Vrste roda Bacillus jedne su od najistraživanijih bakterija koje mogu doprinositi poboljšanju rasta biljaka. U ovom radu je izolovano sedam Bacillus izolata iz rizosfere lucerke (Medicago sativa). Ispitivana je sposobnost produkcije jedinjenja kao što su vodonik-cijanid, indol-3-sirćetna kiselina I siderofore. Procenjena je I sposobnost indukcije klijavosti na semena pšenice (Triticum aestivum) I ječma (Hordeum jubatum). Izolat BMG2 je proizveo najviše indol-3-sirćetne kiseline (28.89 µg/mL). Dužina korenčića je povećana za 60%, dok je dužina izdanka uvećana 2.23 puta primenom izolata PAZE-6 i BMG1. Pored toga, izolati BMG1, BMG2 i PAZE-6, su poboljšali klijavost obe vrste semena I pokazali sposobnost da proizvedu korisne supstance kao što su sideroforei indol-3sirćetna kiselina. Na dalje bi ovi izolati mogli da se koriste u proizvodnji tečnih aditiva koji bi povećali prinos kultivisanih biljaka, a posebno ječma.

The inhibitory effect of indigenous Pseudomonas strains on Fusarium spp. isolated from seeds of a new variety of carrot - 'Vizija' and their effects on seed germination were observed. Pseudomonas spp. strains were applied as bacterial suspensions (culture, 106 CFU mL-1) and cell-free supernatant (CFSa -106 and CFSb -108 CFU mL-1) fractions by sowing seeds during 7 (I) and 14 (II) days of incubation. The germination of control 'Vizija' seeds was 19% after the first and 40% after the second incubation period. Pseudomonas chlororaphis Q16 strain exhibited statistically significant increases in seed germination with all applied fractions and incubation periods, showing values of 43-62% and 55.5-91%, i.e. increments of 24-43% and 15.5-51% compared to the control, after 7 and 14 days of incubation, respectively. P. chlororaphis K35 showed lower but significantly different seed germination values (38-67%) for all variants, except for 7 days old culture. Pseudomonas sp. Ek1 had weaker seed germination potential, showing statistically significant increment only for CFSa,b (I) and CFSb (II) fractions. All tested Pseudomonas strains inhibited the growth of three Fusarium species isolated from 'Vizija' seeds: F. solani, F. oxysporum and F. subglutinans. Natural infection was observed in 20% (I) and 54% (II) of 'Vizija' seeds. P. chlororaphis K35 was the most efficient antifungal strain, reducing seed infection 97.5-100%, followed by Q16 with 95-100%, showing no statistically significant mutual difference. Pseudomonas sp. Ek1 showed a weaker antifungal activity and reduced seed infection by 85-96.75%. The application of P. chlororaphis Q16 and K35 as strains effective in improvement of carrot seed germination and growth inhibition of the seed pathogens F. solani, F. oxysporum and F. subglutinans, can be further tested in carrot production for more beneficial effects., Ispitivan je inhibitorni efekat autohtonih Pseudomonas sojeva na gljive Fusarium spp. izolovane sa semena šargarepe sorte 'Vizija' i njihov uticaj na klijavost semena. Pseudomonas spp. sojevi su primenjeni u vidu bakterijske suspenzije (kulture, 106 CFU mL-1) i supernatanta (CFSa -106 i CFSb -108 CFU mL-1) potapanjem semena, a potom inkubirani tokom 7 (I) i 14 (II) dana. Klijavost semena 'Vizije' u kontroli iznosila je 19% posle prvog i 40% posle drugog perioda inkubacije. P. chlororaphis Q16 soj je uzrokovao statistički značajno povećanje klijavosti semena pri primeni svih frakcija i tokom oba inkubaciona perioda, dostižući 43-62% i 55.5-91% klijavosti, što je povećanje od 24-43% i 15.5-51% u poređenju sa kontrolom, posle 7 i 14 dana inkubacije. P. chlororaphis K35 je uslovio manje, ali statistički značajne vrednosti klijavosti semena (38-67%) za sve varijante, osim za kulturu posle 7 dana. Pseudomonas sp. Ek1 je pokazao slabiji potencijal klijavosti, sa statistički značajnim povećanjem samo za CFSa,b (I) i CFSb (II) frakcije. Svi ispitani Pseudomonas sojevi su inhibirali tri vrste gljiva iz roda Fusarium koje su izolovane sa semena 'Vizije': F. solani, F. oxysporum i F. subglutinans. Prirodna infekcija semena je uočena kod 20% (I) i 54% (II) semena 'Vizije' u kontrolnoj varijanti. P. chlororaphis K35 je ispoljio najače antifungalno dejstvo, sa smanjenjem infekcije semena 97.5-100%, a zatim soj Q16 sa 95-100%, bez statističke značajnosti među njima. Pseudomonas sp. Ek1 je ispoljio slabiju antifungalnu aktivnost i redukovao infekciju semena 85-96.75%. Primena P. chlororaphis Q16 i K35, kao sojeva koji efikasno povećavaju klijavost semena šargarepe i inhibiraju rast patogena semena F. solani, F. oxysporum i F. subglutinans, biće dalje testirana u proizvodnji šargarepe kako bi se procenili ostali pozitivni efekti ovih sojeva.

Application of microbial inoculants to the soil can improve the nutrient uptake by plants and increase the productivity of the crops. Inoculants should ensure a suitable microenvironment and long survival of bacteria in biological fertilizer and after application to seeds. The immobilization of rhizobia onto a carrier can involve the covering and protecting of the microorganisms. Spray drying is a relatively new immobilization technique for the immobilization of microorganisms onto a carrier and it is rarely used for rhizobia. The survival of bacteria during spray drying immobilization onto alginate based carriers was just 8.1 and 6.8% for Bradyrhizobium spp. strains 542 and 526. The working temperature during drying process was high (outlet 50°C) and it presents more than temperature limit for rhizobia survival. Accordingly, the obtained results were justifiably low in value. The presence of sucrose in liquid inoculant had a positive influence on the survival of rhizobia during immobilization.

This paper outlines effects of the usage of two plant growth promoting (PGP) strains: Bacillus sp. strain Q3 and Pseudomonas chlororaphis strain Q16 trough vegetative experiments, performed in semi-controlled conditions on acid soils (Lessivated Cambisols). The studied parameters were chemical properties of soil and PGP effects of strains and their mixture on two wheat (Triticum aestivum L.) cultivars - NS 40S and CCB Ingenio. The seeds treatments with Q3 reduced the occurrence of Blumeria graminis f. sp. tritici natural infection only on CCB Ingenio (46.1%). The additional foliar treatment with Q3 decreased disease incidence (DI) 76.22% (CCB Ingenio) and 75.87% (NS 40S). Reduced initial DI of 77% caused Q16 solely or mixed with Q3 on cv. NS 40S and additional foliar treatment reduced DI to 16.30% (CCB Ingenio) and to 6.35% (NS 40S). The mixture of strains decreased DI to 14.69% (CCB Ingenio) and to 6.09% (NS 40S). Despite the effects of applied strains on wheat growth were affected by limited production capacity of soil and the extreme climatic conditions, SDW of inoculated cultivars were increased by 17-39% (NS 40S) and 35-43% (CCB Ingenio). The N increment ranged from 59% (Q3) to 152% (Q16) for cv. CCB Ingenio. Finding that the seeds treatments improved the plant biomass and N content (Q16) and decreased powdery mildew DI, we can recommended application of Q16 strain as biofertilizer for both wheat cultivars. Depending on wheat cultivar, the additional foliar treatments to prevent powdery mildew infection will be set up for further trials

The impact of intercropping green bean (Phaseolus vulgaris L.) with red beet (Beta vulgaris L. var. rubra) and radish (Raphanus sativus L.), two non-legume plants, on the plants' yields, as well as the effect on occurrence and enumeration of microorganisms in the rhizosphere was studied. The intercrop efficacy evaluation, using Land equivalent ratio, revealed values above 1.0 for all intercropped treatments. Diversity of rhizobia from green bean nodules under different intercropping and fertilizing conditions was observed. On the basis of morphological and biochemical characteristics, 67 out of 158 isolates from green bean roots were selected as rhizobia (42.4%), confirmed by detection of 780 bp nifH gene fragments in nifH-PCR, and then clustered in 27 phenotype patterns. Production of exopolysaccharide succinoglycan was observed in 23 rhizobial isolates, while 6 were detected to solubilize tricalcium phosphate. Screening of genetic diversity using (GTG)(5)-PCR fingerprinting showed presence of six different patterns on the 92% similarity level.

In the greenhouse experiment, the possibility of alfalfa (Medicago sativa L.) growth promotion by inoculation of preceding barley (Hordeum vulgare L.), with plant growth promoting rhizobacteria (PGPR) was examined. The aim of experiment was to select the effective strains as biofertilizer applied in plant rotation. Effects of inoculation with two Azotobacter and two Pseudomonas strains as well as one Sinorhizobium, Enterobacter and Bacillus strain on shoot dry weight and total N content of alfalfa were determined. The results pointed out significant plant growth promotion abilities of strains A1, A2 and P1 which increased alfalfa shoot dry weight over untreated control Ø, by 41, 39 and 35 %, respectively. These three strains increased total N content of alfalfa plants by 34.92 - 40.45% in respect to control Ø. The presented study showed a significant positive influence of preceding barley inoculation with rhizobacteria alone and their mixture on shoot yield and total N content of alfalfa. Results indicated that strains of Azotobacter sp., Pseudomonas sp. and Enterobacter sp. alone can be investigated in further researches as potential agents of biofertilizer for plant growth promotion of alfalfa., U eksprimentu u sudovima ispitana je mogućnost poboljšanja rasta lucerke (Medicago sativa L.) pomoću inokulacije ječma (Hordeum vulgare L.) kao preduseva bakterijama koje poboljšavaju rast biljaka (PGPR). Cilj eksperimenta je bio odabiranje efikasnih sojeva koji bi se primenili u plodoredu u formi biološkog đubriva. U radu je korišćeno sedam sojeva koji pripadaju sledećim bakterijskim vrstama: Sinorhizobium meliloti, Bacillus megaterium, Enterobacter sp, Azotobacter sp, kao i vrsti Pseudomonas sp. Efekat inokulacije ječma primenjenim sojevima je određen na osnovu suve nadzemne mase (SDW) i sadržaja ukupnog azota (N) u biljnoj masi lucerke. Rezultati su ukazali na sposobnost nekih sojeva da poboljšaju rast biljaka. Značajno je povećan prinos lucerke u odnosu na kontrolu Ø (lucerka gajena posle neinokulisanog ječma kao preduseva) inokulacijom sojevima Azotobacter-a A1 (41%) i A2 (39%) i Pseudomonas-a P1 (35%). Sadržaj ukupnog N je bio u korelaciji sa vrednostima SDW. Rezultati su ukazali na uticaj inokulacije ječma kao preduseva na prinos lucerke i njen kvalitet kao i da sojevi Azotobacter sp., Pseudomonas sp. i Enterobacter sp. imaju PGPR potencijal što daje osnovu za dalja ispitivanja i mogućnost primene kao bio­đubriva.

Due to unfavorable terrain configuration on the great of deposols of the 'Kolubara' open cast mine, recultivation under forest cultures has been performed. Tests of basic agrochemical properties as well as quantitative abundance of some groups of microorganisms in deposols of different oldness and under different forest cultures have been done. The tested deposols have shown favorable pH, low content of humus and total nitrogen, readily available to phosphorus and potassium. The biogenity shown is satisfactory but the total microflora, fungi and Clostridium abundance is lower compared to the control soil while the other physiological groups of microorganisms are considerably more abundant., Zbog nepovoljne konfiguracije terena, na većini trajno odloženih zemljišta (deposola) rudarskog basena 'Kolubara' rekultivacija je izvedena pošumljavanjem. Izvršeno je ispitivanje osnovnih agrohemijskih osobina, kao i kvantitativne zastupljenosti pojedinih grupa mikroorganizama u deposolima različite starosti i pod različitim šumskim kulturama. Ispitivani deposoli su pokazali povoljniji pH od kontrolnog zemljišta, niži sadržaj humusa, ukupnog N i lako pristupačnog K2O, a viši sadržaj lako pristupačnog P2O5. Opšta biogenost je bila zadovoljavajuća, s tim što je zastupljenost ukupne mikroflore, gljivica i bakterija iz roda Clostridium bila manja nego kod kontrolnog zemljišta, dok je zastupljenost ostalih fizioloških grupa mikroorganizama bila znatno veća.

The object of this study was to evaluate the possible PGPR effects of ryegrass inoculation with Pseudomonas sp. strains as well as its coinoculation with Rhizobium trifolii on the yield and quality of Italian ryegrassm, with the aim to select effective strains as biofertilizer. The inoculation effects of PGPR on the yield of Italian Ryegrass cultivar K-29t were examined in pot experiment under greenhouse conditions. The experiment was designed with 3 inoculated treatments with 3 replications in completely randomised system. Inoculation of ryegrass with two Pseudomonas sp. strains LG and L1K alone as well as strain coinoculation with strains L1K and Rhizobium trfolii 459 represented treatments which were compared with control uninoculated treatment-Ø. The response of plant to the inoculation and coinoculation was positive in comparison to uninoculated plants. Results showed a significant positive influence of coinoculation with strains R. trifilii 459 and Pseudomonas sp. LG as well as Pseudomonas sp. L1K alone on shoot yield, N and P contents of Italian ryegrass. Results indicated that Pseudomonas sp. strains L1K and LG alone and in coinoculation with rhizobial strains can be investigated in further researches as potential agent of biofertilizer for plant growth promotion of Italian ryerass., U eksperimentu u sudovima ispitivan je PGPR efekat sojeva Pseudomonas sp. kao i koinokulacija sa Rhizobium trifolii 459 na prinos i kvalitet italijanskog ljulja, Lolium multiflorum Lam. kroz prvi i drugi otkos a u cilju selekcije efikasnih sojeva kao biofertilizatora. Kao biljka domaćin, korišćena je sorta italijanskog ljulja K-29. Eksperiment se sastojao od tri tretmana sa inokulacijom i jednim kontrolnim neinokulisanim tretmanom u 3 ponavljanja u kompletno randomiziranom sistemu. Uticaj inokulacije italijanskog ljulja sa pojedinačnim sojevima LG i L1K kao i koinokulacije sa L1K i Rhizobium trfolii 459 ocenjen je kroz analizu određenih parametara (suva nadzemna masa, ukupan sadržaj N i P u suvoj nadzemnoj masi) koji su poređeni sa kontrolnim neinokulisanim tretmanom. Odgovor biljaka na inokulaciju i koinokulaciju je bio pozitivan u poređenju sa kontrolom. Prema rezultatima, koinokulacija ljulja sojevima R. trifilii 459 and Pseudomonas sp. LG kao i inokulacija pojedinačnim sojevima LG i L1K su uticali na značajno povečanje prinosa suve nadzemne mase u oba otkosa ali i sadržaja N i P u nadzemnom delu biljke. Rezultati su ukazali da sojevi Pseudomionasa samostalno ili u inokulaciji sa sojem R. trifolii imaju potencijal za unapređenje rasta italijanskog ljulja i da predstavljaju potencijalne agense biofertilizatora.