It was a conflict that could not be buried in time as pests develop resistance, leading to a cycle of farmers working to overcome the highly adaptive insects that inch their way back to crop stands.

However, with science working double time and in the deepest recesses of genetic materials, improved crop varieties were produced using genes coming from sources other than those from the plant genome.

Dr. Candida Adalla, director of the Department of Agriculture (DA) Biotechnology Implementation Program, said this “truly revolutionized our crops’ improvement process and also challenges our way at looking into the strategies and techniques of managing pest problems.”

Adalla, a professor at the Crop Protection Cluster of the University of the Philippines in Los Baños (UPLB), Laguna, said crops have been bred to combat high-dose insect resistance, which means these crops are engineered to kill pests en masse.

She cited the current transgenic crops such as the Bacillus thuringiensis (Bt) corn and Bt cotton, which provide higher dose mechanisms that wipe out the pest population that attack genetically modified (GM) crops.

Alongside Bt corn technology is the requirement for farmers to ensure that resistance management recommendations were understood and fully complied with, Adalla added.

“This indicates that while the technology promises comparatively high yield advantage over traditionally bred varieties, the technology is very much knowledge-based, and this requires good level of education for the end-users to ensure that the ecological risks are minimized and they reap economic benefits,” she noted.

New technologies
New technologies are actually being developed to increase and stabilize production due to the current pressure for food growers to secure increased yield of high-quality crops.

Proper management techniques had not been observed in the past and experts believe it could be one reason infestation increased and became serious threats.

In her paper “Management of Pests: Principles, Concepts and Practices,” Adalla cited some of these technologies and situations that include:

• Expanded irrigation that allowed intensive cropping and provided continued food supply.

• Development and expansion of farms for high-yielding varieties that also required more inputs.

• Increase in fertilizer use that make possible the denser growth of crops, which rodents and hoppers particularly like.

• Pesticide use in response to more pest problems may lead to higher profits but this could only be realized with the proper use of farm inputs. (However, misuse can result in more problems and economic yield losses. An example is the reduction in efficacy of what originally was a very effective insecticide or technically referred to as insecticide resistance.)

• Expanded cultivation of farmlands, disturbing natural environments and allowing pests to increase in numbers and transfer from wild hosts to cultivate species.

Adalla said that pest problems brought about by new production technologies are not unique to specific environments.

In the past, the response to pest problems was the repeated use of pesticides.

Over the years, however, the concept of pest control has changed from dependence to highly toxic, broad-spectrum pesticides to the use of selective crop-protection products that are less disruptive of the environment.

The concept of eradication has also changed to management, bringing about the rational integration of two more control approaches with the goal of managing pests to reduce their impact on crop yields.

Adalla said that in integrating two or more control tactics to ensure effective pest management “the key is population management and not total eradication.”

Integrated pest management (IPM) would depend on multidisciplinary ecological strategies that allow agro ecosystem analysis to understand the effects of each tactic and decide on the basis of its long-term impact to the pest and crop environment.

Biotech crops and IPM
Although it takes time, examination of crops by walking through the field is an essential aspect of IPM.

“The most important consideration is that one should know what to look for, however frequently and over what part of the plant is normally colonized and damaged,” Adalla said.

The most important goal of pest management is also the selectivity of pest-control interventions that seek to curb the number of pests specified so that it would have minimal effects on all other components of the environment.

Procedures or pest-control tactics are also devised to suit current technology and be compatible with economic and environmental issues and eventual “economic and social acceptance.”

For example, she said that if the Bt corn, a GM technology, is an option against the dreaded corn borer, then the community should eventually accept it.

In the end, she said that it is the stakeholders who should make the decision because “it is their lives and welfare [that are] at stake.”

In keeping pests from becoming a problem, there is a need to use resistant varieties, whether they are traditional or GM.

Yet, how do GM crops affect IPM tactics and solve the problem of farmers unable to regularly monitor their crops?

According to Adalla, since technology promises a high mortality rate on pests, the concern has been on whether the technology also affects nontarget species, particularly the natural enemies of pests, and the environment, as well.

She said this is where the refuge crops come in, and they have yet to be fully understood and appreciated by farmers.

Adalla pointed out that recent studies have shown that farmers using Bt corn have difficulty accepting the idea of allocating a portion of their field for another variety of corn or crop to serve as a refuge, with the possibility of their being devastated by pests.

She said the current very high rate of adoption of Bt corn indicates a need to seriously ensure the refuge requirement is followed “if we are to sustain the gains of this important technological breakthrough.”

Adalla said the way forward is for IPM to become a “way of life” for Philippine agriculture.

“It’s a shift in how technocrats and farmers look at the farm and the pest situations and make decisions,” she noted.

When she had a lecture before members of the crop-protection industry, Adalla advised them that instead of just spending a lot in developing a product, they should spend “more time in understanding how to sustainably benefit from it.”

She said that IPM should be given a chance to flourish among farmers to make their ventures “truly profitable and sustainable.”