Agriculture officials and technicians from the Southern Tagalog Region recently received seeds of tungro-resistant rice varieties (photo) developed at the world’s leading rice research center. The seeds were handed over during their visit to the the International Rice Research Institute (IRRI). The officials were from the Regional Crop Protection Center (RCPC IV-A) of the Department of Agriculture (DA) and field technicians represented Liliw and Magdalena municipalities in Laguna province.

"I'm glad we can help local farmers and we look forward to a continuing partnership," said Chris Croombes, director of IRRI's Human Resources, who assisted with the seed distribution to the visitors.

 

"One of the functions of the crop protection center is to diagnose problems affecting rice farmers," said Dr. Cecille Marie C. Manzanilla, RCPC chief. "During one of our visits to farmers, we saw that several of their fields were affected by what looked like rice tungro virus. So, we asked IRRI to confirm the virus's presence." Precy Esmejarada and Norberto Licong, agricultural technicians from Liliw and Magdalena, respectively, reported that the virus disease is a common problem in their towns.

 

Rice tungro, a serious disease caused by viruses transmitted by green leafhoppers, induces leaf discoloration, stunts growth, reduces tiller numbers, and sometimes causes sterile or partly filled grains. Licong observed that farmers frequently exchange tungro-susceptible seeds with other farmers, a practice that could spread the rice tungro virus. Another observation is that farmers don't plant at the same time. This asynchronous planting can result in a steady food supply for the leafhoppers.

 

"Asynchronous planting is a major factor because the leafhoppers prefer to eat younger plants," explained Dr. Gilda Jonson, a senior associate scientist at IRRI's Genetics and Biotechnology Division. "Leafhoppers tend to move to newer plants that are growing. But when the rice plants are uniformly planted in the field, this prevents leafhoppers from moving to neighboring fields.” Rice tungro disease is more common during the wet season because insect populations tend to increase when there is a continuous food source.

 

Although asynchronous planting contributes to the problem, farmers continue to practice it. "Farmers in Liliw and Magdalena always plant rice ahead of farmers in other towns because their areas are nearer to the irrigation source," Jonson explained.

“If our farmers plant late, the other farmers at the end of the irrigation line will be affected," added Licong.

“One helpful practice to fight the disease is to plant tungro-resistant rice varieties," says Jonson, "and there are several to choose from."

 

The seeds of tungro-resistant rice varieties that were distributed to the visitors by IRRI included Matatag 2 and 9; NSIC Rc 110, 112, 118, 140, 222, and 238; Japonica 2; and Maligaya special 11.

 

Several of these recommended varieties were developed by IRRI’s Plant Breeding Division and were disseminated through the NextGen project, one of the seven components of the Food Staples Sufficiency Program of the DA and IRRI.

 

Maligaya special 11 and Japonica 2 were developed through the Germplasm Utilization Value Added (GUVA) project of Korea's Rural Development Administration and IRRI.