Biological control on plant pathogenic fungus, Pythium by using some plant extracts in vivo and in vitro

Abstract The inhibitory activity of 5 plant extracts, Allium sativum, Opuntia ficus-indica, Malva parviflora, Mentha spicata and Plantago lanceolata with concentration 50 % and 100 % were assessed against the mycelial growth of Pythium fungus in vivo and in vitro. Results showed that all the concentrations of plant extracts give significant inhibition in the mycelial growth of Pythium fungus; the highest concentration (100 %) prevented large amounts of mycelial growth followed by lower concentration (50 %) of plant extracts. Opuntia extract at 100 % concentration gave great effective in inhibition of Pythium’s mycelial production, which gave 100 per cent inhibition ratio while 50 per cent concentration gave 77.28 % inhibition ratio followed by other plant extracts, Mentha, Allium sativum, Plantago, then Malva respectively. In vivo experiments, tomato seed infused in five plant extracts separately and then sown with soil contaminated with Pythium fungus and watered after that with these five plant extracts. After 30 days, the length of the stems and roots were measured in centimetres. While the tomato seeds which were soaked with distilled water and then sown in polluted soil with fungus Pythium, and watered with distilled water (control) did not show any growth.