Authors: Parissa Taheri Abdoljabbar Irannejad Morteza Goldani Saeed Tarighi
Publish Date: 2014/08/15
Volume: 140, Issue: 4, Pages: 829-839
Abstract
In this research 4 rice genotypes and 5 Alternaria alternata isolates were used to study the potential of Alternaria isolates obtained from various rice fields to infect the main rice cultivars planted in Iran and determine the levels of rice resistance to this fungus Also we investigated the role of reactive oxygen species ROS enzymatic antioxidants and lignin in basal resistance of rice to this necrotrophic fungus Priming in H2O2 and O2 − accumulation peroxidase POX and superoxide dismutase SOD activity and lignification was observed in Shiroodi as a partially resistant compared to the susceptible Domsiyah cultivar Application of ROS generating systems increased disease development on both cultivars In Shiroodi elevation of O2 − accumulation and SOD activity was observed at 12 h post inoculation hpi which was earlier than enhancement of H2O2 accumulation and POX activity at 24 hpi In addition application of SOD inhibitor reduced H2O2 and lignin levels and increased disease progress Similarly POX inhibitor reduced lignin content of the rice cells which was associated with increased disease index In overall both SOD and POX were associated with lignin formation as a resistance mechanism in riceA alternata interaction However POX had prevailing function in lignification in our pathosystem
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