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Salinity is one of the most brutal environmental factors limiting the productivity of agricultural lands worldwide. It is considered that the salinity may be one of the important reasons for the low yield in Iğdır of the tomato plants, which is medium resistant (3–5 dS.m−1) among vegetables. Eco-friendly techniques such as endophytic root bacteria treatments (ERB) are needed to restore saline soils to agriculture and also to increase the yield of tomatoes. Endophytic bacteria colonizing the inside of plants increase plant growth by various mechanisms and also mitigate the adverse effects of biotic and abiotic stresses on plants. In this study, endophytic bacteria were isolated from the roots of tomato plants exposed to salt stress. Then, these isolates’ tolerance levels to different NaCl (0, 0.1, 0.2, 0.4, 0.8 M) concentrations and their potential to promote plant growth (PGP) traits were determined. It was recorded that 14.8% of the isolates whose salt tolerance was tested were highly tolerant to NaCl and 18.5% were highly susceptible. The tested ERB isolates exhibited typical PGP characteristics such as siderophore production (4–30 mm diameter), phosphate solubilizing activity (6–16 mm diameter), and IAA production activity (24.9–171.6 µg/ml). Moreover, it was determined that the nitrogen fixation potential is high 55.7% of the isolates tested, and 11.1% low. In addition, the effects of ERB treatments on germination and vigor index in two tomato cultivars under standard and saline conditions in the lab were evaluated. Some ERB isolates in tomato plants under standard and saline conditions increased seed viability, hypocotyl length, root length, and seedling fresh weight, and also accelerated germination.

In Turkey, which is among the ancient walnut growing countries of the world, cultivation has been gradually increasing. Nowadays, many orchards are established with the ‘Chandler’ variety. However, it is not possible to obtain the desired level and quality from the walnut varieties. As is known, plant nutrients and beneficial rhizobacteria (BR) applications are important in increasing quality. In this study conducted at the walnut orchard, foliar applications such as urea, potassium nitrate, borax, manganese sulfate, zinc sulfate as well as WH48/1A and WH68 BR were sprayed for 2 years. Following application, fruit characteristics, macro- and micronutrient content of leaf and kernel were determined in ‘Chandler’ variety. According to this, it was observed that foliar application of boron (B) in terms of nut weight (13.29 g) in the first year and the same application in terms of kernel ratio in the second year (54.96%) ranked the first row. Walnut kernel light color with potassium (K) application and kernel dark color with WH68 bacterial application were measured. Moreover, with the K application, the shrinkage ratio was low, whereas the kernel blackening was found to be high. Concerning the macro- and micronutrient content of leaves evaluated, there was an increase in nutrients in both years, except for calcium (Ca) in the first year. In terms of nutrient content of the kernel, there was an increase in nutrients in both years, except copper (Cu) in the first year and phosphorus (P), calcium (Ca), iron (Fe), copper (Cu), manganese (Mn), and B in the second year. The bacterial applications had a significant effect on nut sizes and nutrient content compared to control.

Endophytic bacteria (EB) isolated from healthy cucumber plant tissues (e.g., root, stem, leaves) were evaluated as possible biological control of Pseudomonas syringaepv. lachrymans, the causative agent of angular leaf spot disease in cucumber. In this study, 24 endophytic bacteria were selected for tests based on biocontrol traits such as indole-3-acetic acid and siderophore production, solubilization of phosphate, and inhibition growth of P. syringaepv. lachrymansin vitro.Some of the selected endophytes successfully inhibited the pathogen were tested in pots. In the pot experiment, two isolates (CB361-80) and (CC372-83) were selected as the most promising biocontrol agents tested against the pathogen. According to the identification carried out by using 16S rRNA primers and sequence analysis, the two selected endophyte isolates (CB361-80) and (CC372-83) showed 99% similarity to Ochrobactrum pseudintermediumand Pantoea agglomerans, respectively. Two EB isolates colonized seeds at the rate of 3 × 106–7.1 × 107CFU/g 1 day after seed bacterization. The population of the two EB isolates in cucumber tissues were found to be about 2 × 104–7.5 × 104CFU/g in roots and 3.8 × 104–2.2 × 105CFU/g in shoots 45 days after seed bacterization. The populations of the two isolates in the root and shoot tissues did not decrease following the inoculation of the pathogenic bacterium. The endophytic strains CB361-80 (Ochrobactrumsp.)and CC372-83 (Pantoeasp.)successfully colonized the cucumber tissues.

Background: Bacterial canker and subsequent gummosis are caused by multiple pathogens and lead to significant yield and productivity losses in sweet cherry cultivation in Turkey. This study identified that Pseudomonas syringaepathovars were responsible for bacterial canker on sweet cherry orchards by using classical and molecular methods and evaluated the biocontrol effects of bacteriophages against P. syringaepv. syringae. Results: Pathogenic bacteria were isolated from samples taken from plants showing symptoms of bacterial canker in cherry orchards located in İzmir and Manisa provinces. Specific pathogens were identified using pathogenicity, phenotypic tests, and simplex PCR. Bacteriophages effective against P. syringaestrains were isolated from soil contaminated with pathogens identified in the diseased orchards using an optimized isolation protocol. The biocontrol activity of bacteriophage isolates against P. syringaepv. syringaewas tested in vitro and in vivo. The results of pathogenicity tests on immature sweet cherry fruits and micropropagated cherry plantlets revealed 10 pathogenic bacteria isolates from 44 plant samples taken from sweet cherry orchards showing symptoms of bacterial canker. Conclusions: Ten isolates were identified as Pseudomonas syringaepv. syringae. Nine different pure bacteriophage isolates were effective. The results indicated that bacteriophage isolates may demonstrate variable reactivity against P. syringaepathovars.