Investigation of the defense genes expression of Phenylalanine Ammoniumase and Peroxidase in interaction with Neem extract of and Meloidogyne javanica nematodes in tomato
Volume 9, Issue 4, Winter 2019, Pages 360-377
https://doi.org/10.52547/JCT.9.4.360
Fatemeh Naserinasab, Ramin Heydari, Forough Sanjarian, Farshad Rakhshandehroo
Abstract Aim: The aim of this research was to investigate the effects of different concentrations of Azadirachta indica )neem( aqueous extract on the expression of the encoding genes of the two phenylalanine ammonialysis and peroxidase enzymes in tomato (Matin and Early Urbana cultivars) in the interaction with root knot nematode caused by Meloidogyne javanica.
Material and methods: The tomato seedlings were inoculated in the 4-6 leafed stages with different concentrations of the neem extract and then incubated with the pathogen. The plants sampling were at six time points (0, 12, 24, 96, 192 and 288 hours) after pathogen inoculation. The gene expression of the defense enzymes was investigated using the Real-time PCR techniques.
Results: In both cultivars, the gene expression of POX and PAL enzymes in the combined treatment of the pathogen nematode and the aqueous neem extract had increasing trend with significant difference with the control. In Matin cultivar, the increase of the gene expression was higher and faster than of Early Urbana cultivar, so that the expression of PAL and POX genes in this cultivar was 18.2 and 14.5 times more than the control. In the early Urbana cultivar, the highest rate of PAL gene expression was observed at 19.2 hours and was 7.5 times, and in the case of POX gene at 96 hours and 3.9 times when it was compared with control. In greenhouse experiments, the nematode pathogenicity indexes showed a significant decrease compared with the Early Urbana cultivar.
Conclusion: According to the results, in order to protect the plant against the invasions of the patients, the expression of the defensive genes should be increased at the earliest stages after the inoculation of the patient. Early increase in expression of genes in the seedlings treated with neem extract seems to be a justifiable phenomenon in the plant resistance to the pathogenic agent.
Investigation of the peroxidase and catalase enzymes activity and expression level of it’s encoding genes in pathogen stress (Penicillium expansum) and Walnut green skin extract condition in apple fruits
Volume 9, Issue 2, Autumn 2018, Pages 159-175
https://doi.org/10.52547/JCT.9.2.159
E Zangooei, E Bazgir, J Gholamnejad, M darvishnia
Abstract Aim: The aim of this study was to evaluate the effect of walnut green skin extract on blue mold apple, peroxidase activity and catalase activity, as well as the level of gene expression of these two enzymes.
Material and methods: In this study, extracts of green skin of walnut were used to control the apple blue mold caused by Penicillium expansum, in vitro and in vivo. Then, the effect of the aqueous extract of this plant on the activity and also expression of the genes of the two enzymes of peroxidase and catalase were evaluated.
Results: The results of the extract mixed with culture media tests showed the aqueous and methanolic extracts of green walnut skin inhibit with the rate of 86.41 and 75.84 percent of the fungal pathogen were respectively the best treatment in comparison with the control. In vivo test (the 4 ° C), the spot surface, in the treatment of aqueous and alcoholic extracts with a concentration of 6×1000, reduced 94.50 and 81.69%, respectively. In the test for the activity of peroxidase and catalase activity, the walnut skin extract increase the activity of these enzymes at 9th day. The results of enzymes genes expression showed that the expression of peroxidase and catalase genes was 227.66 and 314.08 fold on day 9, in the plant extract+ pathogen treatment, respectively.
Conclusion: The extract of walnut skin had direct fungal effects, and it can was induce the defense genes expression and subsequently increased activity of defense enzymes.