Skip to main content Skip to navigation

Ecologically-Based Participatory IPM For Southeast Asia

USAID/IPM CRSP Annual Report Year 3 (2008)

Strawberry IPM utilizing native predatory mites for biological control of spider mites in La Trinidad, province of Benguet

Prinicpal Investigators: Beverly S. Gerdeman and Lynell K. Tanigoshi


Develop an understanding of the pest complex in La Trinidad strawberry fields with an emphasis on spider mites.


Continued intensive sampling of mites from all strawberry producing barangays in La Trinidad Municipality. The purpose of this activity is to develop a reference of both pest and beneficial mite species found on strawberry. Following identifications and curation, this reference collection will serve as a useful guide for students and researchers who would benefit from a taxonomic voucher collection and is currently the Philippines’ most comprehensive collection of pest and beneficial mite species inhabiting strawberry.

This survey could help clarify the phenology, between spider mites, host plant and the beneficial predatory mites. Efforts will continue to develop a predictive calendar to alert farmers to monitor, increasing the chances of utilizing control methods such as predatory mites, earlier in the season when they are most effective. Information from the survey could elucidate effects of climate, individual management techniques such as nutrient management and cultural practices, on the pests and beneficial species found on strawberry.

Research methods and outputs

The final survey was completed from April-June of 2008. The methods were the same as in 2007 with strawberry plants selected from farmer’s fields representing all the strawberry producing barangays. In the field, the strawberry plant canopy was separated from the crown and roots and each portion bagged separately and transported back to the laboratory. Samples were placed in a Berlese’ funnel, for extraction of acarine and insect species. Resulting samples were sorted, mounted and dried. Slides were tentatively identified, and then transported to Isabela province for final verification by Dr. Leonila Raros, acarology professor emeritus, UPLB. The reference collection now totals over 400 slides and includes three pest families collected from the canopy and eleven families of predatory mites located in the canopy and crown and soil interface (Table 1). The collection will be housed in an air-conditioned room at the La Trinidad Office of the Municipal Agriculturist.

Table 1a. Pests.
Pests Genera Species
Tetranychidae 3 6
Tarsonemidae 1 1
Eriophyidae 1 1
Tenuipalpidae 1 1
Table 1b. Beneficials.
Beneficials Genera Species
Ascidae 2 2
Bdellidae 1 1
Cheyletidae 1 1
Cunaxidae 2 2
Eupodidae 1 1
Laelapidae 2 2
Macrochelidae 1 1
Parasitidae 1 1
Phytoseiidae 7 12
Rhodacaridae 1 1
Stigmaeidae 2 2


Understanding the guava mite complex.


Guava leaves from the Municipality Bahong nursery where placed on cyclamen infested strawberry plants. Within two weeks normal leaves appeared. The predatory mite complex inhabiting the guava leaves effectively controlled the cyclamen causing damage to strawberry plants.

Research methods and outputs

Monthly leaf samples were collected for 1 year. Identifications were made of predatory mites inhabiting the guava (Table 2). Six primary predatory species inhabiting guava were identified: Amblyseius herbicolus, Paraphytoseius orientalis, Typhlodromips yandala, Neoseiulus longispinosus, Laseoseius sp. and Euseius ovalis. The feeding preference tests for each species are in progress.

Table 2.
Family Genera Species
Phytoseiidae 6 5
Ascidae 1 1
Cunaxidae 1 1
Stigmeidae 1 1
Cheyletidae 1 1


Mass rearing of Neoseiulus longispinosus, a native predatory, phytoseiid mite.


The primary objective of this project is the mass production of the native predatory mite Neoseiulus longispinosus. Three methods for mass-production were developed including the identifying of an alternative emergency host plant for use during the rainy season and as a back-up.

Research methods and outputs

  • An effective cultural method for the control of fungal pathogens of spider mites in laboratory conditions was developed.
  • An alternative host plant was tested as an emergency method for mass rearing spider mites, serving as food for the predatory mites, during the rainy season.

Small-scale production

As an alternative to mass-production, a pilot project was undertaken with the Long long strawberry grower’s association to determine the feasibility of a small-scale, on-farm production method of the beneficial mites. Training and results were presented to the association and interested farmers. Participants included both men and women farmers and laborers. Two meetings were held and results discussed. The demo plot results of a female cooperator, Juana’s, further supported those of similar cooperative projects in the previous two years. The rearing requirements in the highland areas of La Trinidad were found to be different than those for the lowlands, underscoring the complexity of the region.

Large-scale production

During year 3, regionally suitable mass-production methods for N. longispinosus were developed and implemented in the laboratory and field. A field insectary was developed to test if spider mites (as food for predatory mites) could be mass-produced in a bean field located in the warmest location of the La Trinidad municipality, Alno. A farmer cooperator was paid to plant and maintain bush beans. The beans were inoculated with spider mites. The results were not as good as expected, primarily due to late season planting. The increasing rainy periods promoted rust on the beans, deterring spider mites. Beans will be planted under a tunnel to test if protection from rain deters rust and increases the chance of spider mites.


Technology transfer.


Technology transfer occurs everyday on many levels. Phin is actively training staff of OPAG and OMAG in the rearing and maintenance of predatory mite cultures. Workshops and trainings were conducted which included interested farmers, laborers, students and academics. A handbook on small-scale rearing was developed and awaits publication. A strawberry IPM manual is currently being produced as a joint project between WSU/USAID and the Office of the Municipal Agriculturist.

Research methods and outputs

The proposed interagency project on the provincial level is now underway. For the first time, cooperating farmers in the “swamp” area (agriculture land leased to farmers by Benguet State University in the lowland area of the Municipality) will have the opportunity to plant strawberries in land protected from pesticide drift and have access to clean water for irrigation. In the current system, farmers are trapped in a land-lease system, whose short-term leases fail to encourage soil amendments and whose close proximity to other farmers promotes overuse of pesticides. These farmers represent a large portion of small farmers in La Trinidad. This opportunity provides participatory training in good agricultural practices including IPM and the use of predatory mites to produce safe strawberries. The proposed demonstration area is a 1-hectare demonstration farm composed of 13 farmer plots in a popular tourist area located in the “swamp” (Fig. 1). The goals of this objective are:

  • Provide a highly visible demonstration plot at the heart of the tourist area, promoting interaction between farmer and consumer. The interaction results in mutual benefit by influencing each other’s practices to produce a healthy berry through IPM and “organic-based” practices. Pesticides are greatly reduced due to judicial oversight as part of the demo protocol and increasing the chances of an industry-wide change.
  • Promote sustainability of the project through inter-agency cooperation in the municipality, representing a sort of “agrarian parliament” binding one another by a system of checks and balances.
  • Provide a roadmap for change to other communities/municipalities.
  • Provide a model for other crops.

A note on gender

The elevations of the Cordillera region of Luzon are approximately 1500m and in some places over a mile high. This rare setting has allowed the production of temperate crops, many commanding much higher prices than similar sized plots of lowland crops. This may have resulted in a different socio-economic pattern affecting traditional gender roles as exhibited by lowland populations. The following points make an interesting argument:

  • High-cash value crops may affect gender roles.
  • The educated “trainers” are primarily women.
  • The climate may have resulted in a “farming elite” not representative of the lowlands.

Women farmers attending the meetings/trainings/workshops are either the successful ones who can afford to pay for labor, allowing time for personal training or older without young families. In the case of our Long long pilot project, I became friends with two of the women farmers, both were older women. One was very successful and the other was married but played the major role in the decision-making and always attended the meetings. In this case socio-economic conditions can affect attendance as well as other traditional gender issues. Employees of OMAG and OPAG in positions responsible for workshop training are primarily women. In addition, I have developed a good repoire with women who are both farmers and laborers and feel my presence encourages them to come to trainings. The final point is that the climate in the Cordilleran region is significantly different than the lowlands and temperate vegetables and fruits are high-cash value crops compared with the traditional tropical crops found in the lowlands. These factors might allow women the luxury of attending meetings and trainings, which could also increase their livelihood. If gender issues can be found to be less of a hindrance careful surveys might reveal this phenomenon and provide important lessons applicable in other regions. Gender issues of these “temperate” peoples should be compared with that of their tropical lowland relatives.

Figure 1. Establishment of a 1-Hectare Demonstration Farm on Organic Based Strawberry Production and Utilization Of Local, Predatory Mites in the Control of Twospotted Spider Mites of Strawberry
Training/Workshops/Meetings Date Activities Agency Cooperators
  • BPI (Bureau of Plant Industry)
  • BSU (Benguet State University)
  • DA (Department of Agriculture)
  • DTI (Department of Trade & Industry)
  • FPA (Fertilizer and Pesticide Authority)
  • JAEC (Japan Agricultural Exchange Council)
  • MOA (Memorandum of Agreement)
  • OMAG (Office of the Municipal Agriculturist)
  • OPAG (Office of the Provincial Agriculturist)
  • OTOP (One Town, One Product. A promotion)
  • WSU (Washington State University)
Proposal of a demonstration plot in the “swamp” area to provide a safe area for farmers to try good farming practices overseen by experts from all cooperating agencies. April 2008 Introduce the cooperative idea to all agencies and Governor Fongwan WSU/USAID, OMAG, OPAG, DA, BPI, FPA, BSU
(40 attendees, 15 female)
Interagency meeting to establish demo farm 21 August 2008 Site identification OPAG, OMAG, DA, BSU, WSU/USAID
(8 attendees, 2 female)
Pre-orientation meeting on organic based strawberry production. 27 August 2008 Project objectives explained to farmers. 13 cooperator farmers agreed to terms and conditions of the project. BSU, WSU/USAID, OMAG, OPAG, 11 farmer cooperators
(17 attendees, 3 female)
Technical briefing and workshop on organic based strawberry production. 5 September 2008
  • Explanation of organic based strawberry production.
  • OMAG and OPAG will provide soft loan to farmers to augment start-up capital.
  • BSU will help in marketing of fresh strawberries to high-end markets.
  • Irrigation water will be purified using carbonized rice hulls.
  • DA will provide clean planting materials for nursery propagation.
  • WSU/USAID, OPAG, OMAG will spearhead mass rearing and field releases of predatory mites.
OMAG, OPAG, BSU, WSU and 14 farmers, JAEC.
(29 attendees, 6 female).
Inter-agency pilot project on organic based strawberry production 16 September 2008
  • Distinction made between approaches: organic production or organic based production.
  • Farmers prefer organic based production and positive response on the use of predatory mites.
BSU, WSU/USAID, OMAG, OPAG, BPI, DA and 13 farmer cooperators.
(31 attendees, 5 female)
Workshop on the upgrading of OTOP products coming from the proposed
inter-agency demo.
3 October 2008
  • Processors demand god quality fresh strawberries to be processed into wines, jams, cakes and cosmetics.
  • Farmer leader assured processors they will follow GAP to meet their demands.
OMAG, farmer leader, DTI, 20 processors headed by Mrs. Maria Que.
(27 attendees, 25 female)
Meeting with farmer cooperators 4 October 2008
  • Documentation of farming activities.
  • Hauling and distribution of compost.
  • Signing of MOA regarding capital augmentation to be provided by the LGU of La Trinidad.
OMAG, 13 farmer cooperators
(15 attendees, 1 female)