KORONADAL CITY – A state of calamity was declared in South Cotabato after rice pests and floods destroyed hundreds of farms.

Vice Gov. Elordo Ojena, who also presides over the provincial board, said Thursday that the board passed a resolution on Wednesday placing the province under a state of calamity.

The resolution was passed on the request of Gov. Daisy Avance-Fuentes, he said.

Earlier, the towns of Polomolok, Tupi, Surallah, and Sto. Niño were placed under a state of calamity after farms there were destroyed by flash floods and attacks of the rice pest black bug.

The pest, also known as the Malaysian black bug, attacks rice stems and yam. It infests the bases of rice stems and drains them of sap causing the plants to weaken. The stalks eventually die.

The bugs have a maximum height of 8-9 mm and a life span of 200 days. They are capable of producing 680 eggs during their life span.

Ojena said aside from black bugs and flash floods, a whirlwind recently hit the town of Tupi, destroying houses and hundreds of hectares of papaya plantations.

Ojena said officials would use the province’s P21 million in calamity funds to help in relief efforts.

“Millions [of pesos] worth of farm crops and infrastructures were destroyed. Other farmers in the province could only harvest about 10 to 15 sacks of palay per hectare,” Ojena said.

History of destruction

In 2002, most of Mindanao rice farms were heavily infested by black bugs, which, according to authorities, originated from Malaysia and were observed in the Philippines as early as the 1970s.

Black bug infestation occurred in Davao Oriental, Davao del Sur, Bukidnon, Agusan, Maguindanao, North Cotabato, Compostela Valley, and Surigao provinces, according to Noimi Lamata of the crop division of the Department of Agriculture in Southern Mindanao.
Lamata said the extent of the damage brought down production in rice areas at that time.

But Lamata said one of the most effective measures that farmers employed to fight black bugs was the use of mercury bulbs. Light, she said, attracted and trapped the pests.

The technique can still be used in case of infestation. Once trapped, the pests are burned.

Agriculture technicians said another way to control the pest is through the use of the microbial control agent metharizium.

Natural enemies

Metharizium is a kind of fungus that kills black bugs.

There are also a host of other biological agents that can be used to control black bugs, including ground beetles, spiders, and red ants.

The International Rice Research Institute (IRRI) also said ducks and toads are considered effective natural enemies of the black bug as they eat the pest’s nymphs and adults.

“Black bugs grow in rain-fed and irrigated wetland environments, continuously cropped irrigated areas, densely and poorly drained fields,” the IRRI said.

Another contributing factor, the IRRI said, is the excessive use of nitrogen and the presence of alternative hosts or plants.

“Black bug flight patterns are also affected by the lunar cycle and on full moon nights, large numbers of adults swarm to light sources,” IRRI said.

“Staggered planting of the rice crop and excessive nitrogen favors the buildup of the pest.”

In controlling the pest, IRRI said, it is important that the rice field is rid of weeds and dry during the plowing phase.