It is possible to grow Japonica rice in the Philippines

By Miriam Du-Baltazar, Ph.D.

Rice has two major types: Indica and Japonica. In the Philippines, Indica rice is more common than Japonica rice. Japonica rice varieties thrive well in temperate areas. As they are not well adapted to tropical weather like Indica varieties, there is a smaller area planted to Japonica rice production in the country than Indica rice varieties; hence, a lower supply in the market.

The cultural management practices for Japonica rice production are relatively similar to that of Indica. However, Japonica rice commands higher prices than the typical Indica varieties because of its excellent eating quality, making it more profitable for farmers.

Cultivating Japonica rice in Cavite would generate increased income for farmers. Of the three Japonica varieties, MS 11 gives the best profit, both as raw palay or milled rice in both seasons. Japonica 1 and Japonica 2 are preferably cultivated during the dry season rather than in the wet season. A higher income can be observed if farmers sell ttheir produce as milled rice instead of as raw palay.

Their individual annual net income can reach Php 113,059.22 from raw palay and Php 179,018.37 from milled rice from a one hectare Japonica rice field.

Steps in Producing Japonica Rice

The steps to follow in producing Japonica rice include the choice of seeds; land preparation; seedling preparation and transplanting; fertilizer application; water management; weed management; pest management; harvesting and threshing; drying and storing; and milling.

1. Choice of seeds: Use filled, healthy and good quality seeds with high percentages of germination. Sources of good seeds are the International Rice Research Institute (IRRI) and the Philippine Rice Research Institute (PhilRice).

2. Land preparation: Prepare the land 2–3 weeks prior to transplanting to ensure that weed emergence is suppressed. Plow the field 21 days before transplanting (DBT) at a depth of approximately 10–15 centimeters (cm). If possible, apply rice straw and other crop residues before plowing. Harrow the field 1 week after plowing and repeat 1–2 DBT followed by leveling.

3. Seedling preparation and transplanting

Wet-Bed Method

• Seedbed preparation: Select a site near the main field with good water supply and access to full sunlight. Use a 400 square meter (m2) seedbed for every 1 hectare of field to be transplanted. Use 20-30 kilograms (kg) of seeds. For easy management, the seedbed must be 1.5–2 meters (m) wide.

Irrigate the area for one week then plow and harrow thrice 21 days before sowing. Construct small canals of 0.4 m wide in between seedbed plots. Collect the soil from constructed irrigation canals and put on the bed to raise it to 5 cm above the original soil level. Incorporate 30–40 bags (600–800 kg) of mixed rice hull and carbonized rice hull mixture for healthy seedling growth and easier pulling.

• Seed preparation: Soak the seeds in clean water for 24 hours. Change the water every 6 hours to avoid fermentation. The seeds may also be placed in running water. Remove the seeds from the water and place them in a clean container. Cover and keep airtight for 12–24 or until “white dots” or swollen embryos are observed.

• Sowing and seedling management: Broadcast the pregerminated seeds onto the seedbed. Maintain irrigation in the small canals between the seedbed plots. After 10 days, apply 1.6 kg of 14-14-14 and 3.2 kg 46-0-0 fertilizer. Safeguard the growing seedlings from diseases by using the recommended insecticide or fungicide; snails can be thwarted by applying molluscicide. Keep birds away by placing old VHS or cassette tape ribbons (or anything shiny that could scare birds) around the seedbed.

• Pulling and transplanting: Transplant the 18–21 day old seedlings. Pull the seedlings on the seedbed 1 DBT. Pull them carefully with few seedlings at a time to reduce root damage.

Remove the soils that adhered to the roots by washing them with water. Bundle the seedlings in convenient sizes for easy handling during transplanting. Transport the bundled seedlings to the field where they will be transplanted. Handle the seedlings carefully to enable them to quickly recover from stress. Transplant 2–3 seedlings per hill at a depth of 2–3 cm, with a planting distance of 20 x 20 cm. Replant missing or dead hills within 7 days.

‘Dapog’ Method

• Seedbed preparation: The location and size of the seedbed are similar to that of the wet-bed method. Use 40–60 kg of seeds. Plow and harrow once to prepare the land. Irrigate the soil surface. Outline the bed area using string and bamboo stakes. Collect mud around the outlined area then transfer it to the bed to raise it to 4–5 cm above the original soil level.

Smooth and level the surface of the seedbed. Surround the seedbed with banana bracts or thin plywood about 25 cm high. Allow 1 day for the mud in the seedbed to settle then cover it with plastic sheets.

• Seed preparation: Soak the seeds in clean water for 24 hours or place them in running water. The water should be changed every 6 hours to avoid fermentation. Remove the seeds from the water. Transfer the seeds to a clean container. Cover and keep it airtight for 12–24 hours or until “white dots” or swollen embryos are observed.

• Sowing and seedling management: Broadcast the seeds onto the seedbed. Pack the seeds to make a uniform layer of 3 seeds thick. Use a sprinkler to water the seeds thrice daily. Press the seeds gently with a wooden board daily until the fourth day. This maintains even germination and keeps the roots of the seedling in contact with the plastic sheet. Irrigate the seedbed continuously to a 1-2 cm water level.

Apply recommended insecticide on the seedbed and around it at 5 and 10 days after sowing (DAS). Activities to prevent diseases and pests from infesting the bed are similar to those used in the wet-bed method.

• Transplanting: Transplant the seedlings when they are 10–12 days old. Loosen and roll the dapog into a convenient bundle. Roll the dapog with the leaves turned inward and roots outward. Bring the dapog to the field where they will be planted.

Transplant by tearing a small part (around 4–6 seedlings) of the dapog at each hill at a depth of 2–3 cm with a planting distance of 20 x 20 cm. Replant missing or dead hills within 7 days.

4. Fertilizer application (Basal application): Broadcast basal fertilizer on the last day of harrowing. Repeat application 10–14 DAT. Topdress application-broadcast fertilizer during active tillering and panicle initiation.

5. Water management:

• Seedling stage – Keep the soil damp within the first week after transplanting to control snail infestation and establish better soil-root contact. Irrigate the field to around 2–3 cm after a week.

• Tillering to booting stages – Occasionally drain water from the field to stimulate root penetration and firm anchorage, correct micronutrient imbalances, and drain toxic substances from the soil.

• Flowering stage – Maintain a water level of 2–5 cm to avoid drought stress.

• Ripening stage – Stop irrigation and drain the field 1 week and 2 weeks before the expected harvest time during dry season and wet season, respectively.

6. Weed management: Irrigate the field properly to control weeds. It is important to eliminate weeds within the first 35 DAT. Remove weeds by hand-pulling or herbicide application 30–35 DAT.

7. Pest management:

• Snails – Hand-pick the snails if population is still low; otherwise, apply molluscicide.

• Black bug- Use 2.5-5 kg of Methariziumanisoplie dissolved in 5 spray knapsack while the insect population is still low. Monitor the density of the insect population after 4-6 days after spraying. If there are more than 4 bugs/hill are still present, repeat application within 1 week. Alternatively, install light trappings or use an insecticide recommended by the Office of the Provincial Agriculturist for immediate control of the insect.

• Rice blast – Apply recommended amount of fungicide.

• Stem borer – Use systemic pesticide on the base of the rice plants when high density of white heads and dead heart are observed.

8. Harvesting and threshing: Harvest the crop when almost all the grains are already ripe to increase threshability. Thresh rice immediately after harvesting. Japonica rice is more resistant to grain shattering than Indica rice, making it more difficult to thresh. In the absence of Japonica thresher, the common thresher for Indica can be used. Hold a bundle of harvested Japonica rice then carefully feed the panicle to the thresher without releasing the bundle. Rotate the bundle until all grains are removed. Alternatively, thresh Japonica rice in two passings.

9. Drying and storing: Dry the threshed rice for 2–3 days under the sun or using a mechanical drier. And, store the grains in a dry and cool place free from insects and other pests.

10. Milling: Mill rice with 14% moisture content using a Japonica rice miller if available, to avoid low milling recovery. The typical milling machine can also be used but lower milling recovery rates are to be expected.

References:

• National Seed Industry Council (NSIC), 2008, 2009, 2011. NSIC Approved Varieties Manila, Philippines. (Available at http://www.bpi.da.gov.ph/nsic.html)

• PhilRice. 2007. Field operations manual. Philippine Rice Research Institute, Maligaya, Science City of Muňoz 3119 Nueva Ecija. 120pp.

• Personal communication with Gideon Torollo, researcher of the International Rice Research Institute, Los Banos, Laguna.

This appeared as “Japonica Rice Production” in Agriculture Monthly’s February 2016 issue.