Tahereh Naeemi, , Baratali Fakheri,
Volume 6, Issue 2 (8-2019)
Abstract
Plant growth is greatly influenced by environmental stresses including water deficit, salinity and extreme temperatures. Therefore, the identification of genes, especially regulatory ones whose expression enables plants to adapt to or to tolerate these abiotic stresses, is very essential. MYB proteins, a superfamily of transcription factors, play regulatory roles in developmental processes and in defense responses in plants. Members are characterized by a structurally conserved DNA-binding domain, i.e., the MYB domain. Thus, a factorial experiment in a randomized complete block design with three replications was carried out to investigate the effect of different levels of drought stress on the relative expression of TaMYB73 transcription factor gene using Real Time PCR method at Biotechnology Research Institute of Zabol University. The experimental treatments included durum wheat genotypes (Shabrang, Behrang, Karkheh, Aria and Dena) and drought levels (5, 10, 15, 20 and 25% of field capacity). Seedlings of genotypes
were cultured in pots and drought stress was exerted after 45 days (four to five leaves). Data analysis was performed using Ratio =2 -ΔΔCT and SAS software version 9.1. The results of the 2-way ANOVA for the effect of genotype, drought stress and cross-effects of drought stress on the relative expression of TaMYB73 gene and the amount of osmotic regulators (Proline and Carbohydrate) at different stress levels (20, 15, and 5% of field capacity) were significant in comparison with the normal condition (25% of field capacity) at 1% probability level. With the increase of drought stress level from 5 to 20% of crop capacity, relative to the normal level (25% crop capacity), the relative expression of TaMYB73 gene and osmotic regulators of proline and carbohydrates increased in Beharang, Karkheh and Dena genotypes. Therefore, Karkheh and Dena genotypes showed greater resistance to drought stress among the 5 genotypes studied.
Ilnaz Abolhasani, Javad Baharara, Naser Mahdavi Shahri, Elaheh Amini,
Volume 7, Issue 1 (4-2020)
Abstract
In traditional medicine, extracts of polysaccharide-containing plants are widely employed for the treatment of cutaneus wounds. The brittle star, as one of marine organisms, encompasses bioactive compounds, which confer the healing potency of damaged arms. The aim of the present study is to investigate the effects of extracted polysaccharide from the Persian Gulf brittle star )Ophiocoma erinaceus( on male Wistar rat skin wound healing. In this experimental study, 60 male Wistar rats were divided randomly into 5 groups including control, positive control (treatment with honey), experimental 1 to 3 (treatment with 12.5, 25, 37.5 mg/kg body weight of extracted polysaccharide, respectively). In all groups, the wound was inflicted in the posterior part of the body of rats. Then, rats were treated locally. On the 3th, 7th, 10th and 14th days, samples were collected from the healing hole and histological changes were investigated by light microscopy. Then, quantitative data were analyzed by SPSS software, one-way ANOVA at the level of p<0.05. Microscopic results showed that, in treated wounds by 37.5 mg/kg of extracted polysaccharide, as well as positive control, the re-epithelialization, the angiogenesis and the attenuation of inflammatory cells were significantly improved in comparison with the control group. Maximum epithelium thickness (on the 7th day) and minimum inflammatory cells (on the 14th day) were observed in the experimental group 3 (treated with 37.5 mg/kg of extracted polysaccharide) and positive control, as compared with the control group (p≤0.05). The findings of this research indicated that the polysaccharide extracted from O. erinaceus accelerated the cutaneus wound healing in male rats, which can be used as a natural component in the development of natural source agents for the treatment of cutaneous wounds.
