Performance of Irrigated Lowland Rice Grown at Different Spacing and Organic Fertilizer Levels Under Unflooded Water Management System During the Vegetative Growth Period

Abstract

A field experiment was conducted to evaluate the growth and yield performance of irrigated lowland rice variety “PSB Rc18” grown at different spacing applied with varying levels of organic fertilizer under unflooded water management system, and to evaluate the profitability of growing lowland rice using wide spacing adopting the System Rice Intensification (SRI) and organic fertilizer under unflooded water management system during the vegetative growth period.

Lowland rice can be productively grown under unflooded water management system during the vegetative stage using organic fertilizer at the rate of 15 t ha^-1 at 40 cm x 40 cm planting distance. Application of 15 t ha^-1 organic fertilizer enhanced heading and maturity and produced more productive tillers than the control. However, application of organic fertilizer applied at 15 t ha^-1 resulted in lower net income (Php 11,932.00) compared to 7.5 t ha^-1 (Php 14,457.00) because of higher input cost. In this option, if the raw materials of producing organic fertilizers are available, and the farmers need not buy any of those, application at 15 t ha^-1 is more profitable because of higher yield of 3.92 t ha^-1 than at 7.5 t ha^-1 with only 3.05 t ha^-1.