Growth and Grain Yield of Rice as Affected by Timing of Nitrogen Application
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PROJECT TITLE: Growth and Grain Yield of Rice (Oryza sativa cv. PSB Rc18) as Influenced by Timing of Nitrogen Application PROPONENTS: Pretty D. Faigmani Cristine Diane B. Dimayuga Lipa City National Science High School
MENTOR:
Prof. Bong M. Salazar Crop Physiology Division, Crop Science Cluster College of Agriculture, UP Los Baños
ABSTRACT
A greenhouse experiment using the rice cultivar PSB Rc18 was conducted from October 2011 to March 2012 at University of the Philippines Los Baños to determine the effect of timing of nitrogen application on the growth and grain yield of rice. Nitrogen, when applied before transplanting, at tillering (40 days after sowing; DAS), and at flagleaf emergence (70 DAS) improved growth and increased grain yield (4.79 t ha-1) of PSB Rc18 by increasing the relative leaf chlorophyll content which is associated with better photosynthesis and consequently, higher total biomass. When applied at later growth stage (85 DAS), nitrogen resulted in relatively lower grain yield (4.64 t ha-1) because of poor assimilate partitioning to the grains. Experiment results also showed that nitrogen increased final grain yield by increasing the number of spikelets per square meter.
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INTRODUCTION
Rice (Oryza sativa) is the most important food crop of the Philippines and is the staple item of Filipino diet. The country is the eight largest producer of rice in the world, accounting for 2.8% of global rice production. In 2010, nearly 15.7 million metric tons of palay were produced, which accounted for 21.86% of gross value added in agriculture and 2.37% of GNP. The national average yield, however, remained relatively low compared with that of other Asian countries. The country is also the world's largest rice importer in 2010; about 10% of local demand is supplied by imports (FAOSTAT, 2010; IRRI, 2010). Rice is produced extensively in Luzon, Western Visayas, Southern Mindanao, and Central Mindanao. Since the mid-1960s yields have increased
PROJECT TITLE: Growth and Grain Yield of Rice (Oryza sativa cv. PSB Rc18) as Influenced by Timing of Nitrogen Application PROPONENTS: Pretty D. Faigmani Cristine Diane B. Dimayuga Lipa City National Science High School
MENTOR:
Prof. Bong M. Salazar Crop Physiology Division, Crop Science Cluster College of Agriculture, UP Los Baños
ABSTRACT
A greenhouse experiment using the rice cultivar PSB Rc18 was conducted from October 2011 to March 2012 at University of the Philippines Los Baños to determine the effect of timing of nitrogen application on the growth and grain yield of rice. Nitrogen, when applied before transplanting, at tillering (40 days after sowing; DAS), and at flagleaf emergence (70 DAS) improved growth and increased grain yield (4.79 t ha-1) of PSB Rc18 by increasing the relative leaf chlorophyll content which is associated with better photosynthesis and consequently, higher total biomass. When applied at later growth stage (85 DAS), nitrogen resulted in relatively lower grain yield (4.64 t ha-1) because of poor assimilate partitioning to the grains. Experiment results also showed that nitrogen increased final grain yield by increasing the number of spikelets per square meter.
2
INTRODUCTION
Rice (Oryza sativa) is the most important food crop of the Philippines and is the staple item of Filipino diet. The country is the eight largest producer of rice in the world, accounting for 2.8% of global rice production. In 2010, nearly 15.7 million metric tons of palay were produced, which accounted for 21.86% of gross value added in agriculture and 2.37% of GNP. The national average yield, however, remained relatively low compared with that of other Asian countries. The country is also the world's largest rice importer in 2010; about 10% of local demand is supplied by imports (FAOSTAT, 2010; IRRI, 2010). Rice is produced extensively in Luzon, Western Visayas, Southern Mindanao, and Central Mindanao. Since the mid-1960s yields have increased