Dr.Swastiko: Rodents Threaten the Rice Self-Sufficiency Program

Rice is the most important food commodities, and also has a very important political value for Indonesia. Undeniably, the current Indonesian society has a very high dependence on rice commodities, therefore the government has to import rice annually. The statement was delivered by Dr.Ir.Swastiko Priyambodo, M.Sc. when he was invited as speaker at  the Expert Dialogue on Rural Press RRI Bogor recently.

Dr Swastiko the Lecturer of the Department of Plant Protection, Faculty of Agriculture said, the high demand of rice for Indonesian has caused the Indonesian to practice intensive rice cultivation. "One of the important biotic limiting factors in rice cultivation is the infestation of plant pests and diseases, including weeds," he said.

Based on the reality on the fields, he said, there are three important pests that attack rice in Indonesia, namely field mouse or Rattus argentiventer, Nilaparvata lugens or brown planthopper, and white and yellow rice stem borer or Scirpophaga innotata and S. incertulas.
    
In addition to attacking the rice plant, Dr. Swastiko asserted, field mouse also attack other food crops and palawija such as corn, soybeans, beans, peanuts, sweet potatoes, and cassava. According to him, field mouse also important pests on the plantation commodities such as oil palm, coconut, cocoa, and sugar cane. "The intensity on the rice fields attack by  rats generally ranging from 10 to 20 percent per year, and it will decrease the national rice production inot 10 percent," he said.

Furthermore, he said, a variety of techniques and methods on pest management have been developed to control the field mouse population and to reduce the damage they cause. Various techniques and methods include clean cultivation, cultivation methods which includes seedling systems, planting time, and spacing of cropping systems, the use of traps (trapping), utilization of natural enemies (natural enemies) in the form of predators and pathogens, as well as the use of chemicals (poison baiting and fumigants).

However, according to Dr.Swastiko, the damage caused by field mouse are still plenty. In fact, at certain times in certain areas of damage caused by field mouse even occur in high intensity and even to puso. Thus, integrated and consistent efforts to control such rodent pests are required to have an effective and efficient results.

Although the utilization of rat predators such as white owl (Tyto alba, Family Tytonidae, the Strigiformes of Aves) have been developed in oil palm plantations and they  are quite effective. However, the utilization of these predators in controlling rats in paddy fields still encountered many obstacles.

He emphasized, one example of the manual control to field mouse  is the technique commonly called Trap Barrier System (TBS) which is a combination of using traps, plastic fence, and trap crops such as rice plants were planted three weeks earlier.

Those non-chemicals technique, is considered quite effective to be applied to rice fields with high intensive attack by field mouse, and it proves capable to suppress the population of field mouse significantly. Always use extreme care when using any poison, particularly where pets, livestock or other non-targets (predators) can find it.

Chemical control is one of the most effective method to control rodents, both indoors or in the fields (outdoors), due to its practical application and the evaluation of its results.

Rodenticides are pest control chemicals intended to kill rodents. Generally they are consisted of basic rat bait (cereal), toxic materials, and additional materials or other carrier materials. Further Dr. Swastiko explained that commercially Rodenticides are divided into two major groups of: anticoagulants and other compounds. 

"The acute oral toxicity of the anticoagulant rodenticide works by disrupting the nervous system of mice and rats within 3 hours after they eat ing rat poison," he said. Instead, he said, chronic poison has a slow work, i.e. by inhibiting blood coagulation or clotting rats (anticoagulation) and coupled with a break capillaries in the organs, these baits are capable of producing death in mice within 3 days. "By considering the differences in the workings of both the active ingredient, the acute toxic recommended for use in the management of the mice at the time of high population, the reverse chronic poison is used when the rat population is low to moderate, as well as to keep the pest population levels remain below economic threshold, "he concluded. (Wied).