Written by Ella Lois T Bestil
In the rainfed area in Tabtabungao, La Union, rice yield increased amid water crisis. Fields lack supplemental irrigation; yet, farmers attained 4 t/ha – thanks to Aerobic Rice Technology (ART). The yield is a feat, as farmers used to harvest 2-2.5 t/ha.
ART is a cropping system that uses less water than the traditional practice, which takes about 3,000-5,000 l of water to produce a kilo of palay. Engr. Junel B. Soriano, technology proponent and vice president for research, extension, and training at the Bulacan State Agricultural State College (BASC), said aerobic rice grows well in non-flooded and non-puddled soils using supplementary irrigation.
“Through this technique, rice is grown like maize or wheat,” he said.
From several farmer participatory researches they conducted, Soriano’s team found that ART requires low inputs and less management without reducing yield.
The right variety first
Soriano said choosing the right variety for ART is important. NSIC Rc192 or Sahod Ulan 1 and PSB Rc9 or Apo, drought-tolerant varieties, were found to be suitable in Bulacan and La Union.
“NSIC Rc192 and PSB Rc9 can withstand tension in their cells under water stress, making them rigid and erect. When the stress period ends, these varieties can also recover quickly,” said Thelma Padolina, head of PhilRice Plant Breeding and Biotechnology Division.
In a study conducted by BASC and Don Mariano Marcos Memorial State University in La Union, fields planted with PSB Rc9 yielded 4.1 – 6 t/ha. Fields with and without supplemental irrigation were compared in rainfed and upland ecosystems.
Managing pest, water, and nutrients
Nemencio Concepcion, ART farmer-cooperator at Mataas na Parang, San Ildefonso, Bulacan harvested 7t/ha for practicing the technique.
Concepcion said a well-prepared field is necessary. Seeds are directly sown in the furrow at 2-3 cm deep with 25-35cm spacing.
If the soil is dry, Soriano said field must be irrigated after seeding to enhance seed germination. Pre-emergence herbicide will be applied after first irrigation and post-emergence herbicide at 20-25 days after emergence (DAE).
“At flowering stage, flood irrigation is done at 5-7 cm water depth. In the wet season, irrigation is no longer a challenge as these varieties can grow normally even without rainfall within two weeks,” Soriano said.
As regards nutrient management, Soriano said ART is easy-on-pockets.
“ART-cultivated crops need less cost for labor and inputs. Hand weeding is easy with its planting distance,” Soriano said. He also recommended applying four bags of complete fertilizer for a hectare at 10-15 DAE.
For early and late-maturing varieties, three bags of ammonium sulfate or 1.5 bags/ha of urea is enough at 25-30 DAE and 30-35 DAE, respectively.
ART was introduced by the International Rice Research Institute in 2001 in collaboration with Philippine Rice Research Institute and the National Irrigation Administration.