The influence of plant growth–promoting rhizobacteria on growth and enzyme activities in wheat and spinach plants

A pot experiment in a greenhouse was conducted in order to investigate the effect of different N₂‐fixing, phytohormone‐producing, and P‐solubilizing bacterial species on wheat and spinach growth and enzyme activities. Growth parameters and the activities of four enzymes, glucose‐6‐phosphate dehydrogenase (G6PD; EC 1.1.1.49), 6‐phosphogluconate dehydrogenase (6PGD; EC 1.1.1.44), glutathione reductase (GR; EC 1.8.1.7), and glutathione S‐transferase (GST; EC 2.5.1.18) were determined in the leaves of wheat (Triticum aestivum L., Konya) and spinach (Spinacia oleracea L.), noninoculated and inoculated with nine plant growth–promoting rhizobacteria (PGPR: Bacillus cereus RC18, Bacillus licheniformis RC08, Bacillus megaterium RC07, Bacillus subtilis RC11, Bacillus OSU‐142, Bacillus M‐13, Pseudomonas putida RC06, Paenibacillus polymyxa RC05 and RC14). Among the strains used in the present study, six PGPR exhibited nitrogenase activity and four were efficient in phosphate solubilization; all bacterial strains were efficient in indole acetic acid (IAA) production and significantly increased growth of wheat and spinach. Inoculation with PGPR increased wheat shoot fresh weight by 16.2%–53.8% and spinach shoot fresh weight by 2.2%–53.4% over control. PGPR inoculation gave leaf area increases by 6.0%–47.0% in wheat and 5.3%–49.3% in spinach. Inoculation increased plant height by 2.2%–24.6% and 1.9%–36.8% in wheat and spinach, respectively. A close relationship between plant growth and enzyme activities such as G6PD, 6PGD, GR, and GST was demonstrated. Plant‐growth response was variable and dependent on the inoculant strain, enzyme activity, plant species, and growth parameter evaluated. In particular, the N₂‐fixing bacterial strains RC05, RC06, RC14, and OSU‐142 and the P‐solubilizing strains RC07 and RC08 have great potential in being formulated and used as biofertilizers.     

The Effects of Colemanite Deposits on the Arsenic Concentrations of Soil and Ground Water in Igdeköy-Emet,Kütahya,Turkey

Water, Air, &; Soil Pollution - The hydrochemical study of the area surrounding the Hisarc?k (Emet-Kütahya) colemanite mine shows extremely high arsenic contamination in ground water...     

Use of ISSR,SRAP, and RAPD markers to assess genetic diversity in Turkish melons

The genetic relationships among 63 melon (Cucumis melo L.) genotypes collected from various regions of Turkey were determined by comparing their molecular ISSR, SRAP, and RAPD markers with those of 19 foreign melon genotypes to investigate the taxonomic relationships and genetic variation of Turkish melon germplasm. Total 162 polymorphic markers (69, 18, and 75 obtained from ISSR, SRAP, and RAPD primers, respectively) were used to define the genetic similarity among the melon genotypes by dendrogram or two and three dimensional scalings. The average similarity (SM coefficient) between any two pairs of accessions examined as estimated by molecular variation was 0.73 ± 0.48. Within-group genetic similarities ranged between 0.46 and 0.96. Related genotypes or genotypes collected from similar regions were partitioned to similar clusters. Southeastern Anatolian genotypes were distinctly apart from group inodorus and group cantalupensis (sweet) genotypes. This reinforced the position of Turkey in the secondary genetic diversity center of melon. The genetic diversity among Turkish genotypes (H = 0.28 and I = 0.42) was only a little less than that of the world accessions (H = 0.30 and I = 0.45). On the other hand, the percentage of polymorphic loci among Turkish melon genotypes (90.7%) was even higher than that of the world accessions (87.6%).     

Determination of Graft Compatibility of Pear Cultivars Grafted on Different Rootstocks by Carbohydrate Analyses

In modern pear cultivation, clonal quince and pear rootstocks are preferred because they are easy to maintain and harvest. Also, they form dwarf plants and improve fruit quality compared to pear seedling rootstocks. However, graft incompatibility can be involved between different species or genera. The aim of the study was to determine the graft compatibility of the ‘Deveci’ and ‘Williams’ pear cultivars with different pear and quince rootstocks by carbohydrate analysis. Carbohydrate accumulation in the graft union was also observed with iodized potassium iodide (KI) staining. In terms of rootstocks, there were no differences in starch and carbohydrate content, but statistically differences were found in sugar contents. Significant differences were also found between cultivars and graft union in terms of the examined traits. Sugar content was highest in OHxF 333 and lowest in seedling rootstocks. There were no statistical differences in the starch content between the graft unions of the ‘Deveci’ cultivar, while starch accumulation was higher above the graft union than below and graft union in the ‘Williams’ cultivar grafted on the quince rootstock. In the study, it was determined that there were higher carbohydrate accumulation in the scion and graft union than below the graft union in ‘Williams’ grafted quince rootstocks, which was also confirmed by staining with KI. As a result of the study, it was concluded that carbohydrate accumulation analysis can be used to determine the graft compatibility of the pear cultivars with the different quince and pear rootstocks.

     

Effect of Organic Materials on Yields and Nutrient Accumulation of Wheat

ABSTRACT

This experiment was conducted under greenhouse conditions using a sandy clay loam treated with garbage and mushroom composts, cattle and chicken manures, or municipal sludge at rates of 0, 30, or 60 ton ha^?1. The organic materials were applied to the pots and incubated for 15 d. The soil samples were watered at field capacity. In this experiment, wheat (Triticum aestivum L.) was used as a test crop. At the end of the experiment, it was found that treating sandy clay loam with the organic materials increased plant total and grain yields, protein content, 1000-kernel weight, number of grains in spike, and accumulation of nitrogen (N), phosphorus (P), potassium (K), iron (Fe), zinc (Zn), and manganese (Mn) by wheat compared with the control treatment, depending on the organic material applications. Thus, the increases were found to be statistically significant (P ≤ 0.05). Among the types of organic materials, the sewage sludge was the most effective material in increasing N, P, K, Fe, Zn, and Mn content of leaf, grain, and stem samples of the wheat plant. It was followed by mushroom compost and cattle manure. Based on the results, sewage sludge and garbage compost are suggested for use as an amendment for the soil studied. Comparing the beneficial effects of the organic materials applied for improving plant growth and nutrient accumulation, the materials can be arranged in the following descending order: municipal sludge > chicken manure > cattle manure > garbage compost > mushroom compost. It is suggested that recycling of organic materials for agricultural usage as an organic-matter resource is an alternative, organic fertilization option in Turkey.     

Fungal pathogens of oregano occurring at the breeding plots in Ankara

Journal of Plant Diseases and Protection - Fungal pathogens cause significant losses both in terms of quality and quantity on oregano (Origanum spp.) cultivation. Various fungal diseases on oregano...     

Apilarnil reduces fear and advances sexual development in male broilers but has no effect on growth

1. An experiment was conducted to determine the possibility of stimulating sexual development at an early age in male and female broiler chickens by administration of apilarnil, a natural bee product, in the pre-pubertal period.

2. From 28 to 55 d of age, birds were given apilarnil orally. The effects of low (2.5 g/bird) and high (7.5 g/bird) doses of apilarnil on growth performance, testicular weight, secondary sexual characteristics, blood lipids, testosterone and fearful behaviour were evaluated.

3. Apilarnil administration did not cause a positive effect on growth performance of male and female broilers suggesting that apilarnil did not have an anabolic effect.

4. Apilarnil administration suppressed blood glucose and cholesterol.

5. Birds receiving apilarnil remained immobile for a shorter period in a tonic imobiliy test and showed less home-cage avoidance responses suggesting a lower level of fearfulness.

6. Increases in testicular weight, testosterone concentration and comb growth in males receiving apilarnil implied that it stimulates the sexual maturation at an early age. However, a similar stimulation of secondary sexual characteristics was not observed in females.     

Selective determination of catechin among phenolic antioxidants with the use of a novel optical fiber reflectance sensor based on indophenol dye formation on nano-sized TiO₂

The optical sensor for "tea catechins" was built by immobilizing 2,2'-(1,4-phenylenedivinylene)bis-8-hydroxyquinoline (PBHQ) on TiO? nanoparticles (NPs). The sensor worked by "indophenol blue" dye formation on PBHQ-immobilized TiO? NPs as a result of p-aminophenol (PAP) autoxidation with dissolved O? at pH 10. Among quercetin, rutin, naringenin, naringin, gallic acid, caffeic acid, ferulic acid, p-coumaric acid, catechin, epicatechin, epicatechin gallate, epigallocatechin, epigallocatechin gallate, and trolox, only catechin group antioxidants delayed the color formation on NPs, as measured by the reflectance signal at 710 nm. For quantitative analysis, reflectance signal versus time was recorded, and the difference between the areas under curve (ΔAUC) in the presence and absence of catechin was correlated (r = 0.98) to catechin concentration. The selectivity of the sensor for catechins was shown in tea infusions compared to other plant extracts and was ascribed to the nonplanar structure of catechin interfering with the formation of perfectly conjugated indophenol blue on TiO? surface.     

Gliadin and zein show similar and improved rheological behavior when mixed with high molecular weight glutenin

Small amplitude and lubricated squeezing flow tests were performed to investigate the effect of high molecular weight glutenin (HMWG) on the rheological properties of gliadin and zein dough composites. It was hypothesized that addition of small amounts of HMWG to zein cause changes in its viscoelastic properties in the same way as its addition to gliadin. Starch (87%, w/w) and protein/protein composites (13%, w/w), and water were mixed into dough. The water content of prepared dough was in the 41.7–45.3% range. Composites were gliadin-HMWG and zein-HMWG. Phase angle and complex modulus (G*) were obtained from frequency sweep tests at 0.5% strain amplitude over a 0.01–100 rad/s frequencies. Lubricated squeezing flow test were carried out at a range of strain rates to determine the sample extensional viscosities.