Variation of Field Resistance to Leaf Blast in the Japanese Upland Rice Cultivar Kuroka in the Philippines

Abstract

The field resistance to leaf blast in nine Japanese upland rice cultivars was evaluated in greenhouse and upland nursery trials at the Philippine Rice Research Institute, the Mountainous Region Agricultural Institute, Aichi Agricultural Research Center, and the Department of Paddy Farming, National Agricultural Research Center for Tohoku Region. In all three institutes, the eight upland rice cultivars showed high levels of field resistance to leaf blast, which were equivalent to those of past evaluations in Japan. However, the cultivar Kuroka showed an intermediately low level of field resistance to the disease at the Philippine Rice Research Institute, although the cultivar exhibited a high level of field resistance at the two Japanese institutes. This result suggests that the level of field resistance to leaf blast in the Japanese upland rice cultivar Kuroka changes in the Philippines.