Cladosporium cladosporioides C24G Modulates Gene Expression and Enzymatic Activity During Leaf Blast Suppression in Rice Plants

The inclusion of biological control in the integrated management of rice blast (Magnaporthe oryzae) is an alternative to reduce pesticides application. C24G, classified, as Cladosporium cladosporioides was isolated from the phylloplane of the rice plant, therefore, adapted to natural conditions of the original habitat. This study aimed to compare four application methods of C24G in rice plants to suppress leaf blast together with the increase in enzymatic activity and expression of defense genes. It was conducted by four assays (1: seed and soil, 2: soil drenching, 3: foliar spray pulverization—preventive and 4: foliar spray pulverization—curative) for choosing the best application method. The best methods identified were further investigated for the activity of Chitinase (CHI), β-1,3-Glucanase (GLU), Lipoxygenase (LOX), Phenylalanine ammonia-lyase (PAL), and Peroxidase (POX) and the expression of Gns1, JIOsPR10, LOX-RLL, and PR1b genes by Real-time PCR. The preventive foliar spray pulverization suppressed up to 83.78% of leaf blast severity, increasing enzymes (CHI, GLU, LOX, and PAL) activity and genes (JIOsPR10, LOX-RLL, and PR1b) expression. We conclude that Cladosporium cladosporioides isolated C24G is a potential biological agent. To prove its potential as a component of sustainable blast management, it should be tested under field conditions. The application of C24G isolate in rice fields can reduce the number of fungicides spraying, generating greater rentability and decreasing environmental contaminations.