THE USE OF SOLAR STERILIZATION OF SOIL PREPARED FOR FOREST SEEDLING AND ITS EFFECT IN INHIBITING THE GROWTH OF SOIL FUNGI AND MOLECULAR DIAGNOSTICS BY USING PCR TECHNIQUE FUNGI

Abstract

The main aim of this study to isolate fungal pathogens from non-sterilized soils and Molecularly diagnosed to know which fungi affected by solar sterilization,Study was made by covering the soil with a black mulch from june to august with (5)cm depth. Isolation after sterilization showed that fungi Neoscytalidium dimidiatum, Penicillium, Aspergillus, Rhizopus and Phoma, were affected with isolation (0)% from the covered soil, while the isolation from untreated soil was (80,5,10,5)% respectively for the same fungi., The maximum temperature recorded was (64.3) °C for the covered soil compared to uncovered soil (42.6) °C, while the lowest temperature recorded was (55) °C for the covered soil compared to uncovered (39)°C, The isolated fungi were examined phenotypically by studying the nature of growth, colors, textures, and the edges of colonies, and the nature of the fungal hyphae. Then diagnosed based on international classification keys (Sutton and Dyko, 1989). when they matched the results of the molecular diagnosis. The analysis showed that diagnosed isolates belonged to: Neoscytalidium dimidiatum, Alternaria alternata, Curvularia, and Fusarium. culmorum. By comparing the sequences of nitrogenous bases with NCBI except Curvularia, were registered under the numbers (OR026671.1), (OR755780.1), and (OR828014.1). By calculating the percentage of dissimilarity and similarity between the fungi there was a genetic closeness between fungi, Neoscytalidium dimidiatum and Fusarium culmorum, at a rate of 0.12. In contrast, the fungi Alternaria alternate and Curvularia showed a percentage of genetic closeness of 0.06, while the percentage of divergence between the two groups was 0.20.

Keywords

• black mulching
• pcr
• solar sterilization
• soil fungi
• temperature effect