Morphological Features Identification and in-Vitro Screening of Chemical Fungicides Against Rigidoporous microporus the Causal Agent of Cinnamon white Root Disease
No Thumbnail Available
Date
2016
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Uva Wellassa University of Sri Lanka
Abstract
Rigidoporus microporus is a wood invasion fungi that causes white root disease in cinnamon (Cinnamomum zeylanicum Blume) which is considered as a lucrative commercial crop in Sri Lanka. This pathogen has the ability to degrade wood by decomposing lignified cell walls using hydrolytic and oxidative enzymes. Rigidoporus microporus is able to survive in soil with the absence of wooden substrates. The white root disease has spread throughout the country's cinnamon growing regions by causing yield losses which eventually leading to economic loss. This disease was mainly identified in the cinnamon plantations where rubber had grown previously. Although this disease causes significant economic loss towards the cinnamon, information regarding the disease, causal organism and control measures are lacking. This study was conducted to identify the morphology of Rigidoporous microporous and in-vitro screening of inhibitory activity of selected fungicides against the causal agent. Sulfur, tebuconazole and hexaconazole were used as the fungicides. Rigidoporus microporus was isolated from the infected roots of cinnamon. Isolated fungus was cultured in PDA at 28±2 and the morphological characters were observed after seven days. White colour fibrous fungal mycelium was observed in infected roots which was firmly attached to the bark of the root. On cultured plate fully grown circular shaped, white color dense fibrous mycelium was observed with many branching like structures. Under the compound microscope, threadlike network was observed with a hyaline septate hypae and clamp connections. Under, in-vitro evaluation of the fungicides, maximum inhibition Of the fungal growth was observed in the tebuconazole & hexaconazole whereas minimum growth inhibition of the colony was observed in sulfur. In this study morphological features of Rigidoporus microporus, the causative organisam of cinnamon white root disease were identified and evaluated the effectiveness of systemic fungicides against the pathogen. . Tebuconazole & hexaconazole were highly effective against the causal agent (Rigidoporus microporus) of cinnamon white root disease.
Description
Keywords
Export Agriculture Degree Programme (EAG)