By Julio P. Yap Jr.

Many have started advocating different organic farming methods. But with the incidence of plant pests and diseases, there is still the need to eradicate or control these problems to make organic farming sustainable.

In the field of biology, a pathogen in the oldest and broadest sense is anything which can cause disease. A pest is a plant or animal which is detrimental to humans or human concerns, such as agriculture or livestock production; thus, in its broadest sense, a pest is a competitor of humanity.

Close-up of an aphid — one of the most destructive insect pests on plants. Aphids can be found on a number of different nursery stock plants.

These pests and diseases include microscopic pathogens and submicroscopic pathogens and insects in the environment which can cause significant damage to plants.Managing these plant pests requires a multi-pronged approach like the use of pesticides and biopesticides.

Pesticides are substances meant for attracting then destroying any pest.The use of pesticides is so common that the term “pesticide” is often considered synonymous with “plant protection product.” Although pesticides have benefits, some also have drawbacks, such as potential toxicity to humans and other species.

To manage plant health problems, it is very important to identify the causal agents accurately, and to isolate the causal agent precisely. Thus, sufficient information from the grower is needed, like healthy versus unhealthy plants, the presence of possible agents responsible for the problem, growing conditions, and growing practices.

Research and Preventive Measures

In an effort to address the problem, researchers from the Central Luzon State University (CLSU) have found at least six plants possessing botanical pesticide or biopesticide properties, which can be an alternative to commercial pesticides. Botanical pesticides or biopesticide are substances derived from plants that are capable of protecting selected crops against certain diseases and pests.

The team of researchers, led by program leader Dr. Paz Alberto of the Institute of Climate Change and Environmental Management (ICCEM), has developed six biopesticides from plants collected in Region 3— Nueva Ecija, Bataan, and Aurora.

Samples of the six biopesticide products that were developed by a team of researchers from the Central Luzon State University.

However, these biopesticides have to be further studied, field-tested, and patented prior to its promotion to the farmers.

Initially, different plant samples were collected from the forests in identified sites. These samples were screened to determine whether they had potential as biopesticides and were later processed into liquid biopesticides.

Dr. Ronaldo Alberto, the focal person of the project, explained that the biopesticides extracted can be applied to crops as a preventive or curative measure. However, the preventive approach is more effective based on their microplot trials involving selected crops like tomato, pepper, bitter gourd, and onion.

The screening of indigenous plants as sources of biopesticides for vegetables, such as lettuce, cabbage, tomato, and sugarcane, is now being done in Region 10 .So far, 11 plant species with pesticidal properties have been collected and are undergoing tests to find out which can be used as biopesticides.

Experts have initially said that biopesticides have no harmful residues detected, can be cheaper than chemical pesticides when locally produced, can be more effective than chemical pesticides in the long-term, and are biodegradable.

Biopesticides have already started to receive more attention as possible substitutes for synthetic chemical plant protection products.

The biopesticides were developed under the Biodiversity Industry Strategic S&T Program (ISP) of the Philippine Council of Agriculture, Aquatic, and Natural Resources Research and Development of the Department of Science and Technology (PCAARRDDOST). It hopes to address the challenges in biodiversity through the assessment and conservation of critical biological diversity for ecosystem services and development of biodiversity based products such as biopesticides, nutraceuticals, food, and novel products.

This appeared in Agriculture Monthly’s September 2016 issue.