Chapter 18 Silicon from rice disease control perspective in Brazil

Abstract

Rice blast and grain discoloration are mainly responsible for significant losses in grain yield and quality both in upland and irrigated ecosystems in Brazil. Rice (Oryza sativa L.) planting in rotation with soybean in extensive, contiguous areas and high input technology provided a conductive environment to diseases which were hitherto unimportant, such as sheath blight in irrigated rice and take-all in upland rice. Even though varietal resistance constitutes a major component in rice disease management, it should be integrated with long-term benefits of silicon (Si) fertilization. A field study conducted with genotypes showing wide variability for grain discoloration and different rates of SiO2 showed promising results. Initial greenhouse inoculation tests are encouraging in controlling leaf blast at the vegetative phase with Si. The logical extension of firmly established existing concepts on Si and rice disease management should rely on multidisciplinary approach and inter-institutional collaboration. Extensive on-farm trials at hot spot locations for diseases will compliment the experimental results and increase the speed and efficacy in accomplishing the desired goals.