Mehrnoush Daneshvar, Mahmood Maleki, Shahryar Shakeri, Amin Baghizadeh,
Volume 6, Issue 4 (12-2019)
Abstract
Phosphorus, the most essential nutrient for plants, becomes quickly unavailable for the plants in the soil. Phosphate solubilizing bacteria (PSB( can play an important role in providing Phosphorus for plants. In this study, the PSBs were screened from plant rhizosphere by Pikovskaya method. Then, the growth rate and phosphate solubilizing ability of 9 superior strains were measured at different temperatures and levels of salinity and pH. The best strain was identified by 16S rDNA gene sequence analysis. Finally, the genetic diversity of phosphate solubilizing strains were examined by RAPD markers. Results showed that 25 strains were capable of solubilizing insoluble phosphates among the 57 isolates studied. Of the nine superior strains, Cke1 had the highest solubilizing index with the average growth rate under all conditions and was introduced as the best PSB strain identified in the present study. 16S rDNA gene sequence analysis showed that this strain belonged to the Enterobacter genus. The results of genetic variation showed that all stains were divided into six groups and three strains that had the lowest similarity with other strains were placed in three separate groups. Given that Cke1 strain has the ability of solubilizing the insoluble phosphate in different stresses, it can be a good candidate for providing phosphorus at temperatures of 30 and 35 °C, 1.2% and 1.8% salinity levels and pH levels of 6 and 8 for the crops.
Mrs Sona Noroozi, Dr Abolfazl Daneshvar, Dr Ali Sattarian, Dr. Elham Amini, Dr. Fatemeh Nasrollahi,
Volume 11, Issue 4 (2-2025)
Abstract
Arceuthobium oxycedri is commonly known as dwarf mistletoe and grows on and infects cypress species. The semi-parasitic plant was observed in three locations of Juniper Reza Abad in Semnan Province, Chahar Bagh Area of Gorgan and Zanjan Province. In this study, the anatomical and micromorphological characteristics of the species were evaluated to facilitate the identification of this semi-parasitic species in Golestan province. The outcomes of the analysis indicated that the estimation of infestation rate in dwarf shrub trees is unattainable through factors such as canopy percentage, stand gender, slope percentage, and slope orientation. Examination of the stem's transverse section revealed that, across all three elevations, there were no variations in brain size between the semicircular cross-section and the sink's thickness. Analysis of pollen demonstrated that every pollen grain is classified as Monad, exhibiting three to five deep and asymmetric grooves of varying sizes (tricolpate). In regards to their morphology, they exhibit an oblatespheroidal shape adorned with sharp exine decorations. Overall, given the novelty of this study on dwarf mistletoe species, the discoveries hold significant systematic implications for the identification of analogous species documented in alternative juniper habitats within Iran.
