Study of Effects of Root Temperature, Corm Size, and Gibberellin on Underground Organs of Saffron (Crocus sativus L.)
June 7, 2024Effect of Mistletoe (Viscum album) on Macronutrients N, P, K and Ca of Hornbeam and Ironwood tree in Hyrcanian Forests-MyEdeh
June 14, 2024
Saffron (Crocus sativus L.) is a perennial herbaceous rosette, which has permanent underground stem bases called bulb or corm and purple petal and red three branch stigmas. The stigmas contain three major compounds, crocins (carotenoids compound responsible for color), picrocrocin (responsible for taste), and safranal (responsible for odor). Crocin which is the carotenoid compound of saffron as an anticancer prevents cancer cell development. In this research saffron collected from Ghaen and Tabas regions was quantified by HPLC and qualified.
Zymography variation of pectinase in Aspergillus niger and Aspergillus flavus
The genus Aspergillus (Anamorph) belongs to Deutromycets and has several species. Some of the species infected humans, animals, plants, and nuts. Most of these species can degrade plant components by production of pectinase enzyme. The species of Aspergillus flavus and Aspergillus niger are the most popular species of this genus. Although these species could be identified using morphological characters, the interspecific and intraspecific variations could not be evaluated. Regarding pectic enzyme selection by the species, the pectic zymogram technique was used as a simple and useful method to identify the species and to detect inter and intraspecific variation. Initially, the collected samples were transferred to the laboratory and moved to the appropriate media after preparation. The pure cultures were obtained for the sample with Aspergillus characteristics. Then Aspergillus fungi were identified microscopically based on morphological characters. As a result, 40 isolates of A. niger and 30 isolates of A. flavus were recognized. Then samples were transferred to liquid media containing citrus pectin as a sole carbon source to induce the secretion of extracellular pectinase enzymes. After incubation for an optimized period, the secreted pectinase enzymes were extracted and concentrated by Cephadex G150 and then loaded on the polyacrylamide horizontal gel and electrophoresed. There were 18 zymogram patterns for A. niger and 8 for A. flavus. The results based on the comparison of the zymogram patterns showed that there is inter and intraspecific variation for studied Aspergillus species. It seems this technique could be used not only for species identification but also to study the epidemiology of the fungs.
Study of soil parameters and biological factors in rhizospher of pinus and acacia at Taleghani and Cheetgar Parks in Tehran province
The knowledge of the effective factors to maintain, revive, and exploit herbal covering regions in which the soil is facing water and nutritional shortage, or even the kinds of plants suffering from salinity and water shortage is of essential importance. In soils suffering from insufficient nutritional elements, the continuation of plant life depends on the presence of microorganisms such as mycorrhizal fungi. Mycorrhizal fungi are useful symbionts for plants and help plants absorb water and nutrients such as phosphorus, nitrogen, potassium, and other minerals. The use of mycorrhizal fungi could also help remove some fundamental problems of stabilizing jungles and green spaces. In this study, two regional parks, (Taleghani Park and Cheetgar Park), which are different in regards to stability and growth of Tehran pinus species (Pinus eldarica) and in case of (Robina pseudo acacia) were selected and were studied and compared from the view of pedology. On the other hand regarding biological factors, mycorrhizal colonization, root phosphorus, and root proline of the selected trees were examined. The soil of the whole region was sandy loam, the pH was the same in whole regions, and the amounts of Na, Cl, and EC were higher in the soil of Taleghani Park. Pinus trees of Taleghani Park which have better growth compared to pinus trees of the Cheetgar park region had significantly (P≤0.05) more root symbiosis than pinus trees in the Cheetgar Park region. Acacia trees in both regions had rather similar growth and there was not a significant difference between the two regions. There was no significant difference in the average of spore numbers for the pinus rhizosphere between the two regions, where the number of spores in the rhizosphere of acacia trees in Taleghani Park compared to station 2 of Cheetgar Park was significantly (P≤0.05) more. Proline content in the root of pinus and acacia in Taleghani Park was significantly more than that in Cheetgar Park. Root phosphorus concentration for pinus and acacia was significantly higher in station 3 of Cheetgar Park than in other stations. There was no significant difference in phosphorus in the root of acacia between different stations. Based on the results, the low concentration of nutrient elements in the soil of Cheetgar Park compared to Taleghani Park could be considered a limiting factor for the growth of pinus trees in this region. Generally, mycorrhizal fungi are abundant in soils with low plant nutrients. In contrast, we found lower mycorrhizal colonization in Cheetgar Park and it could be considered as another growth limiting factor for pinus trees in this region.
Serological identification and Purification of Turnip Mosaic Virus ( TuMV) in the oil–seed rape
Brassica napus (Canola) with mosaic symptoms from Varamin (Khaveh), was fixed on B. rapa in the greenhouse. The samples were collected and tested against TuMV by D.A.Sandwich ELISA using a specific antibody (DSMZ, Braunschweig, Germany). Mechanical inoculation of ELISA-positive samples caused necrotic local lesions on Nicotiana tabacum L cv. White Burley and Chenopodium Amarant color Coste & Reyn, systemic mosaic on - Petunia hybridia Vilm, Nicotiana glutinosa L., Brassica pepo L., Brassica rapa L., Zinnia elegans L. . Purified sample of virus revealed in the sucrose density gradient. Using spectrophotometry at wavelengths of 260 nm and 280 nm the purified virus Varamin of isolate had an absorbance ratio of 1.4. Antiserum was produced by injection of purified virus into New Zealand white rabbit. Electron micrographs of negatively stained row suspension of infected plants and purified virus preparations revealed flexuous, filamentous particles. Iranian isolate virus was transmitted from TuMV–infected plants to healthy plants by Brevicorye brassica in a non – non-persistent manner.
From Journal of Biology
