جستجوی مقالات مرتبط با کلیدواژه « مایکوریزا » در نشریات گروه « بیوتکنولوژی و ژنتیک گیاهی »

Drought stress is a serious threat to agriculture and one of the best options to deal with this problem is the symbiosis of mycorrhiza, which in addition to maintaining the water content in plant tissues can improve the absorption of elements that are deficient in drought conditions and physiological and molecular changes under stress conditions. In this study, the symbiosis effect of mycorrhiza on morphology, proline and expression of UGT73C6  gene in GF677 hybrid rootstock under drought stress was investigated. Due to increasing drought stress, most morphological traits including leaf number, leaf length, root volume, fresh and dry weight decreased, but with the presence of mycorrhiza, leaf length and width decreased and with decreasing root length, root volume increased, as did fresh and dry weight also increased compared to the control. Proline decreased in symbiosis and under stress conditions relative to non-symbiosis ones. All factors of drought stress, mycorrhiza, time and their combination in root tissue had a significant and highly variable effect on UGT73C6  gene expression, but changes in leaf expression were much less severe because the root has both symbiosis conditions and initial exposure to drought stress. In general, symbiosis with mycorrhiza improves plant tolerance to drought stress.

Tomato bushy stunt virus (TBSV), a member of the genus Tombusvirus is one of the causal agents for curly disease in tomato plants. In this study, the interaction between a mycorrhizal fungus, Rhizoglomus irregular, and TBSV in tomato plants was investigated. In a completely randomized design experiment, tomato seedlings were inoculated with R. irregular and after four weeks they were inoculated with TBSV. Four treatments were included: control plants (C), TBSV -infected plants (V), mycorrhizal plants (M), TBSV -infected mycorrhizal plants (MV). Nineteen days after inoculation the infected plants were tested for symptom production and virus accumulation. Results of symptoms evaluation based on the disease severity index showed a lower disease severity in MV plants compared with V plants. Supporting this result, a lower level of virus accumulation was observed in V plants which was more significant at long-term infection. The expression of methylation-related genes including ADK, HEN1 and MET1 was tested by Real-time PCR. Results showed that the expression of these genes was significantly higher in MV plants as compared with V plants. An increase in the expression of methylation-related genes in MV plants indicates that resistance to the virus is likely to occur through methylation and also supports the lower level of virus accumulation in MV plants.