Effects of foliar applied copper and boron on fungal diseases and rice yield on cultivar MR219

Long-term intensive cropping on the same piece of land with high-yielding varieties often exhausts theavailability of soil micronutrients. Poor management of plant micronutrients has become a hurdle in the effortto increase rice production in Malaysia. The new rice variety, MR 219, was introduced to bring the yieldpotential up to 10 t ha-1. However, to sustain the high yield, more N-fertilizer input is needed and this willincrease incidences of disease. Moreover, nutrients imbalance due to limited micronutrients application mayworsen the situation. In this study, two seasons of field experiments were conducted at Sawah Sempadan,Kampung Seri Tiram Jaya, Tanjong Karang (3° 28’ 0” North, 101° 13’ 0” East) in the off season of 2007 (July2007 – November 2007) and the main season of 2008 (January 2008 – May 2008), using high yielding cultivarof MR219 to evaluate the effects of copper (Cu) and boron (B) foliar applications on the reduction of fungaldiseases, and also to evaluate the effects of foliar Cu and B applications on rice production. Nine combinationsof Cu and B treatment at varying levels of Cu (0 – 20 ppm) and B (0 – 20 ppm) were replicated 4 times andapplied through foliar spray at three different times, namely, 30, 45 and 60 days after seeding (DAS). Thefoliar application of Cu and B was found to be able to reduce fungal disease infestation in MR219 rice cultivarand subsequently increase rice yield. Meanwhile, the foliar treatment of Cu and B applied in combination atlevel T7 (7.53 t ha-1), T9 (7.33 t ha-1), T8 (7.28 t ha-1) and T6 (7.06 t ha-1) produced significantly higher (P>0.05) rice yield as compared with the control, T1 (5.75 t ha-1). A significant reduction in disease scoring wasalso recorded in the experiment where foliar treatment at level T9 (20 ppm Cu + 20 ppm B) cut down 5% ofthe disease incidence in MR219 rice plant. Rice yield components such as productive tiller m-2, number ofspikelets panicle-1, percentage of filled grains and 1,000-grain weight have also shown remarkable incrementsas a result of the Cu and B foliar treatment.