نشریه زیست شناسی کاربردی
سال سی و هفتم شماره 1 (بهار 1403)

In order to predict nitrogen remobilization and effect of ammonium nitrate and ammonium sulfate on the efficiency of water and nitrogen consumption in the fennel, a factorial experiment was conducted in a randomized complete block design with three replications. The first factor consisted of planting date at three levels (first: March 13, second: March 27 and third: April 18) and the second factor was nitrogen fertilizer spraying at three levels (ammonium sulfate (21%), ammonium nitrate (25%), and no fertilizer) with concentrations of one in a thousand in beginning of budding stage. The physiological efficiency of nitrogen increased to about 36.5, and the efficiency of water consumption was also increased. Therefore, it can be said that the availability of nitrogen in the plant tissue has a positive effect on the efficiency of water consumption. The results of the mean comparison showed that on the first and second planting date (respectively, with 85.3 and 92.9 mg/g of grain weight), ammonium sulfate foliar spraying treatment produced the highest amount of grain protein. Nevertheless, on the planting date of April 20, ammonium nitrate foliar spraying treatment produced the highest amount of grain protein with 81.12 mg/g of grain weight. Regarding the amount of total chlorophyll, the conditions were different.

In the Iranian Red Data Book, Gypsophile Nepeta (Nepeta eremokosmos Rech. F.) is listed as a threatened species. It is naturally adapted to gypsum habitats. Understanding the relationships between environmental variables and N. eremokosmos distribution helps us apply these findings to establish preservation and cultivation programs. To understand the main adaptive mechanisms of N. eremokosmos to gypsic soils, anatomical analyses were performed. RDA (Redundancy Analysis), Pearson's correlation coefficients between explanatory variables were used to evaluate the effect of environmental factors on the abundance of N. eremokosmos species. Physicochemical characteristics of the soil were investigated in terms of factors including CaCO3, pH, EC (Electrical Conductivity), calcium, magnesium, sodium, potassium, phosphorus, and nitrogen. Idioblasts were clearly observed in this species' leaf parenchyma. There are also mineral crystals such as calcium oxalate in the leaf parenchyma that enable the plant to adapt well to gypsic soils. The calcium content was twice as large in N. eremokosmos habitats as in control sites. EC, pH, and nitrogen factors negatively impact this species' frequency and distribution. Our findings revealed that potassium, gypsum, CaCO3, and sand percentage had an essential role in N. eremokosmos abundance. In the future, this study will screen the critical factors for the domestication and cultivation of this species based on its habitat properties.

T7 RNA polymerase from T7 bacteriophage has suitable features for using in recombinant protein expression or transcription systems. This enzyme does not require additional factors to identify its promoter, operates very specific and only express the genes under T7 promoter. The features of T7 expression system make it important in biotechnology. Therefore, due to the increasing importance of this enzyme, its mass production at low cost is greatly important.

In this research, T7 phage was applied and PCR reaction was performed using T7 RNAPol-specific primers containing the cutting sites for restriction enzymes. After the electrophoresis of PCR product, T7 RNAPol gene and pGEX2TK plasmid were digested by BamHI and EcoRI enzymes and after being purified, the ligation was performed between them. The recombinant pGEX-T7RNAPol plasmid was transformed into the E. coli, by electroporation. Bacterial positive colonies containing the recombinant plasmid were selected using PCR.

After confirming the obtained plasmids by PCR and digestion, they were sequenced and the sequence analysis confirmed the exact T7 RNA polymerase gene according to NCBI accession sequence. This recombinant plasmid was transformed into Rosetta strain of E. coli in order to express. Its positive colonies were selected and liquid culture was carried out. T7 RNAPol protein expression in bacteria was done by inducing with IPTG and after extraction, it was confirmed by SDS-PAGE. This research is a prerequisite for T7 RNA Polymerase commercial and mass production that will be start after the optimization of its expression and purification methods.

Brassinosteroids play an important role in plant growth and development. Seedling is one of the most important factors affecting plant establishment and crop production.

The effects of tomato seed pretreatment with 24-Epibrassinolide (EBL) on germination indicators, seedling growth in the greenhouse and the effect of foliar spraying on plant growth and yield in the field were investigated. The treatments in the germination and seedling production stage included seed soaking (priming) in distilled water (control) and EBL solution with concentrations of 0.25, 0.5 and 0.75 μM for 24 hours. Seedlings obtained by seed priming in EBL (0, 0.5 and 0.75 μM) were transferred to the field and after one month, they were sprayed with concentrations of 0, 0.5 and 0.75 μM.

compared to the control, EBL increased the percentage and speed of seed germination and all physiological and growth parameters, and the effect of 0.75 μM was more significant. The effect of EBL on the measured parameters in the field was also very impressive. Although the effect of seed priming alone in all treatments was significantly better than the foliar spraying alone in all stages, but the combination of these two treatments in both concentrations of 0.5 and 0.75 μM was more significant than seed priming or foliar spraying treatments. Tomato production from the combination of seed priming along with foliar spraying increased by 74% at 0.5 μM and 145% at 0.75 μM concentration compared to the control.

Chitosan is a polysaccharide that elicits numerous defense responses in plants and affects the growth rate and increasing the production of secondary metabolites. Basil (Ocimum basilicum L.), a medical herb, has many varieties in terms of morphology and secondary compounds. Considering the growing trend of salinity and the its risks and the importance of basil in the pharmaceutical and food industries, this study was conducted to investigate the role of chitosan on some physiological and biochemical properties and Phenylalanine ammonia lyase (PAL) enzyme in basil under salinity stress.

After chitosan treatments at a concentration of 200 mg/L, plants were exposed to four levels of NaCl salinity stress, 25, 50, 100 and 150 mM. The activity of PAL enzyme, physiological and biochemical responses were investigated under the effect of the interaction between chitosan and concentrations of salinity stress.

The salinity stress has negative effects on total chlorophyll and carotenoid whereas it increased flavonoid content. In addition, chitosan at high salinity levels had a positive effect on total chlorophyll, and at all salinity levels increased carotenoids content. Catalase and peroxidase enzymes and potassium content of basil also increased in chitosan treatments, which indicates an increase defense response to salinity in plant. Chitosan also increased PAL enzyme activity, as an important parameter in the biosynthesis of phenylpropanoids, which it increased the amount of methyl cavicol of essential oil. In general, the application of chitosan has an effect on the secondary compounds in basil to improve salt-stress tolerance.

Although all flowering plants share similar stages of development in their vegetative and reproductive organs, there is potential for variation in organ conditions due to gene expression. Understanding flower development stages helps comprehend genetic mechanisms for plant organogenesis and morphogenesis. Polygonum bistorta L. is a medicinal plant from the Polygonaceae family. The aim of this study is to examine the anatomical structure of vegetative meristems and investigate several stages of flower development in this species. Hence, this particular species has been gathered from Hamadan Province.

Carmen Zaji, methyl green, hematoxylin, and eosin stains have been used to examine the histology of the plant. An electron microscope photo of the pollen has also been prepared.

The investigation has shown that the vascular system of the root and stem in dicotyledons is similar, with collateral vessels in the stem and alternate and pantropical in the root. The vegetative meristem is prominent and domed, and the pollen is spherical and split (tricoplate). The ovule develops into a slightly protruding fruit with thick, lignin-walled cells containing the embryo, which cotyledons fill the bulk of the seed. Calcium oxalate was not found in the studied organs.

Azospirillum is the nitrogen fixing microorganisms which improves the growth and development of cereals and other gramineae plants in association with their roots. The goal of present study was to investigate the effect of Azospirillum irakense inoculation in combinations with or without auxin (IAA) and/or gibberellin (GA3) treatment on the growth and biochemical parameters of rice (Oryza sative cv. hashemi) seedlings, as well as observing the bacterial colonization process in the root cells.

The roots of 21-days-old rice seedlings were treated with different concentrations (0, 100, 200 ppm) of IAA and/or GA3 for 4 weeks after inoculation with Azosprillum.

The process of bacterial colonization involves the formation of a biofilm, disintegration of the wall, entry of bacteria into root parenchymal cells and development of isolated and scattered colonies. Dry and fresh weight of roots and aerial parts, total dry and fresh weight, and relative growth rate was significantly increased after inoculation with bacteria. The highest level of these parameters was obtained in the seedlings which inoculated with bacteria in combinations with IAA plus GA3 treatment. Meanwhile, the amount of hydrogen peroxide in the roots, soluble protein, soluble sugar and phosphorus was significantly increased in both roots and aerial parts of seedlings after inoculation with bacteria in combinations with IAA plus GA3 treatment, compared to the control.

According to the current results, the application of Azospirillum irakense in combinations with IAA and GA3 treatment is a powerful strategy to improve rice seedlings growth

Due to the resistance of pathogenic bacteria and fungi to common drugs and the inclination towards natural food preservatives, researchers are exploring antimicrobial agents of plant with organic origin as alternative compounds. This study aims to investigate the antibacterial and antifungal properties of various extracts of Vitis vinifera L. cv. Ghizil Uzum grape skin and seeds extracted through different methods.

Grape seed and skin extracts were obtained using maceration, sonication, deep eutectic solvent (DES), and a combination of sonication-DES methods. The antibacterial and antifungal properties of the extracts were determined using the agar well diffusion method, as well as the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) (or minimum fungicidal concentration, MFC) against Staphylococcus aureus, Salmonella typhimurium, Escherichia coli and Listeria monocytogenes as well as on Aspergillus flavus, Fusarium solani, Cladosporium and Penicillium citrinum.

The results showed that the combined sonication-DES method had the lowest MIC (0.78 mg/ml) and MBC (1.56 mg/ml) for the skin and seed extracts, indicating the effectiveness of this method in extracting phenolic compounds compared to other conventional methods (p≤ 0.05). Additionally, L. monocytogenes and S. aureus exhibited the lowest MIC and MBC values among the tested bacteria , while Cladosporium showed the lowest MIC and MFC among the fungi. Furthermore, grape seed extract obtained through the sonication-DES method demonstrated higher capability in controlling and inhibiting the growth of pathogenic bacteria, fungi, and spoilage microorganisms compared to other extraction methods, making it a promising extraction method for herbal compounds.

Obtaining superior kiwi cultivars through the modification of genotypes is an effective step in increasing the qualitative production of the fruit and, as a result, the further prosperity of agriculture and the increase of exports. In this research, it was assumed that there is a difference between the tested genotypes in terms of some biochemical and morphological characteristics; Therefore, considering the high nutritional and economic value of the golden kiwifruit, the aim of this research was comparing some physiological and anatomical indicators related to the nutritional value of kiwifruit in two golden kiwifruit genotypes (Y1) and (Y2).

For this purpose, factors including the length, width and shape of the fruit, internal tissues of the fruit, hairs and lenses, amount of soluble solids, titratable acid, firmness of the fruit tissue, percentage of dry matter, vitamin C, total phenol content and antioxidant capacity of the two genotypes were investigated.

The results of this research showed that the Y2 genotype, except for the fruit taste index, in other characteristics including fruit size, the ratio of the edible flesh of the fruit to its core, the density of individual short hairs and long hairs, as well as in terms of some qualitative and physiological characteristics such as dry matter percentage, fruit texture firmness, vitamin C content, total phenol content and antioxidant capacity had a higher content. Based on the mentioned indicators, it can be said that this genotype has a better commercialization field than the Y1 genotype.

Cucumber mosaic virus is a dominant disease in cucumber and many other crops, which causes a lot of damage worldwide and in Iran. In recent years, the use of defense inducers has received much attention.

In the present study, we tried to investigate the defensive effects of sodium nitroprusside as a biological stimulus on Cucurbita pepo which is considered susceptible to Cucumber mosaic virus. The plants were incubated at the full two-leaf stage by CMV with a concentration of 50 micrograms/ml. After 48 hours, CMV-infected plants were sprayed with SNP in three concentrations of 100, 200 and 300 micrograms/ml. Finally, the level of expression of coat proteins and virus replicase genes, the expression pattern of PAL, GPX1, LOX1, Pr1 and Pr3 genes as well as some morpho-physiological characteristics of Cucurbita plants were evaluated in three repetitions during three weeks.

The results showed that the plants treated with SNP showed an increase in the expression of the studied genes after the infection by CMV. So that, the treated plants showed an increase in the genes expression pattern depending on the concentration of SNP till the third week compared to the control plants. In addition, several physiological characteristics were also improved. In conclusion, the use of SNP can be considered as an effective methodology in the induction of systemic resistance in Cucurbita pepo plants against CMV.