استحثاث المقاومة الجهازية في نبات البندورة-الطماطم Solanum lycopersicom L ضد مرض سقوط البادرات باستعمال خليط من فطور الميكوريزا

Abstract EN

The effect of vesicular-arbuscular mycorrhiza (VAM) in improving the activity of the enzyme peroxidase and its role in controlling tomato damping-off caused by Pythium ultimum was studied in a pot experiment during the 2013 growing season.

Five treatments were compared with a non-treated control (C): in treatment 1, soil was infested only with Pythium (Py), in treatment 2, soil was infested with mycorrhiza only (My), in treatment 3 soil was infested with Pythium and mycorrhiza at sowing (My+Py), in treatment 4, soil was infested with Pythium and two weeks after sowing with Mycorrhiza (Py-My) and in treatment 5, soil was infested with mycorrhiza and two weeks after sowing with Pythium (My-Py).

The results showed that peroxidase concentration in plant tissues 14 days after seed germination in the My treatment (361.91 ^mole/mg) significantly exceeded the other treatments.

In the treatment where mycorrhiza was added before the pathogen peroxidase activity reached 183.73 ^mole/mg, which was 41% significantly higher than the My+Py treatment in which the pathogen and mycorrhizal inoculant were added together at sowing (108.27 ^mole/mg).

The peroxidase concentration increased significantly 28 days after seed germination in the My treatment (687.52 ^mole/mg) as compared with the Py treatment (10.52 ^mole/mg).

Results also showed that in the treatment My-Py, where the mycorrhyzal inoculum was added before the pathogen, peroxidase activity (458.27 |imole/mg) was significantly higher than in the treatment Py+My, when the pathogen was added simultaneously with the vesicular-arbuscular mycorrhizal inoculum (98.67 ^mole/mg).

Furthermore, results showed that 35 days after seed germination, the enzyme concentration was significantly higher in the My-Py treatment (763.39 ^mole/mg) as compared with My+Py treatment (143.5 ^mole/mg).