Agronomic Response, Nutrient Uptake, and Profitability of PSB Rc18 Lowland
Rice Under Organic Production Systems
Minerva L. Gaurana* and Berta C. Ratilla
Department of Agronomy, Visayas State University, Visca, Baybay City, Leyte, Philippines.
*Corresponding author: minervagaurana@gmail.com
Abstract
Despite its popularity, organic farming is supported by relatively limited scientific data as compared
to conventional farming. Our study was conducted to evaluate the changes in soil characteristics,
growth, grain yield, nutrient uptake, and profitability of lowland rice PSB Rc18 grown in organic
production systems. The experiment was laid out in RCBD with four replications and three
treatments. The application of organic materials favorably affected the soil through the increase in
microbial population and N mineralization. Rice grown under T1 exhibited vigorous growth, high
yield (5.6 ton ha-1), but late maturing. On the other hand, rice grown under T2 had earliest heading
and maturation. Though rice grown in T2 were less vigorous, it resulted in acceptable grain yield (4.8
ton ha-1) and comparable to those grown under T1 and T3 (synthetic fertilizer treatment). Nutrient
uptake is similar for T1 and T3, while lowest in T2 which received less inputs. Organic production
systems (T1 and T2) gain lesser profit/benefit if the price of ordinary palay is followed but incurs
more profit/benefit if sold at premium price. Both T1 and T2 are profitable but T2 incurs less
production cost and requires less input than T1, hence, T2 might further be optimized in order to
gain higher grain yield. Ultimately, adoption of organic production practices in rice might be
stimulated with the establishment of organic certification standards and (fixed) price premium for
organic rice.
Keywords: organic production, palay, profitability, soil microbial population, yield
Vol 45:(1) April 2020