IPM and agroecology

Potato (Solanum tuberosum L., Solanum sp.) is a staple diet in many developing countries; it has a high yield potential, but low yields are common and mostly attributed to a wide range of pests. Potato producing farmers in developing countries are faced by about 20 insect pests world-wide, with higher numbers of pest species in potato agroecosystems of the neotropics in regions of potato origin, which are the Andes in Peru and Bolivia. Depending on the potato agroecology a minimum of two to four pests require regular applications of control methods. Without control losses in potato easily can reach 50-80%, contributing to poverty and food insecurity of potato farmers. The potato tuber moth complex (Phthorimaea operculella, Symmetrischema tangolias, and Tecia solanivora), leafminer fly (Liriomyza huidobrensis) as well as Andean potato weevils (Premnotrypes sp.) are the most severe pests either regionally or globally. Although good examples for adopting Integrated Pest Management (IPM) exist, insecticide use is still the most common pest management strategy deployed by farmers. The unilateral use of highly toxic pesticides to protect the potato against pests greatly contributes to the production costs of potato. Moreover, insecticide sprayings pose tangible health risks to farm families, contribute to environmental contamination and secondary pest outbreaks. Safer and cheaper alternatives for pest management are a major contribution to poverty reduction and food security in potato production systems globally with less negative impacts of agriculture on the environment.

The development and adoption of IPM technologies are based on five major areas of basic and applied research:

Ecosystems research

This aims at understanding the interactions and relationships of pests and natural enemies in potato based agro-ecosystems. CIP makes an overall arthropod inventory and builds up reference material. CIP analyzes the effects of pests on crops and assesses the diversity and efficacy of natural antagonists (predators, parasitoids, entomopathogens) for pest control. These studies are related to landscape fragmentation and farmers’ practices, and their effects on insect diversity and the exchange of species among different habitats. This research contributes to understanding the stability and agro-ecosystems resilience to counteract pests (More information).

Pest population ecology and phenology modeling for pest risk assessments

Pests’ development and population dynamics are mainly driven by climatic (abiotic) factors influenced by biological (biotic) and other external factors such as cultural practices used by farmers. An overall understanding of those factors is fundamental for planning IPM. Practical outputs of this research include recommendations to farmers to plan cropping in periods with less risks of pest infestation and optimal harvest times to reduce tuber damage by pests. CIP is interested in developping modeling tools to predict pest population growth potentials under given agro-ecologies. In combination with Geographical Information Systems these models are employed to assess regional and world-wide distribution potentials of pests. Further, they are ideal tools for assessing possible effects of global warming on insect pest populations and their natural enemies. Recently, Insect Life Cycle Modeling (ILCYM) software has been released (www.cipotato.org/ilcym) (More information).

Natural regulation and biological control

This aims at manipulating the self-regulating capacity of agro-ecosystems through adequate cultural practices, as well as through releases of natural enemies for classical biocontrol (parasitoids) and the use of biopesticides (entomopathogens). CIP scientists are studying the natural enemy biology and ecology, including assessments of their efficacy, and developing systems for formulation and application. One important output of this research was the development of a granulovirus-based biopesticide to control the potato tuber moth in potato stores. The product is produced by national programs in Peru and Bolivia, and widely used by farmers. Recently, leafminer fly parasitoids have been introduced to Kenya and parasitoids for biocontrol of the potato tuber moth were introduced to Nepal (More information).

Communication and behavior of insects

This research, aimed at understanding the communication between insect species, studies pest migration and spatial dispersal of pests. This research is fundamental for developing innovative as well as simple systems for effective pest management that can be easily applied by resource-poor farmers. Outputs of this research are the detection of pheromones that can be used for monitoring pests in field and store, or can be formulated together with small amounts of insecticides to attract-and-kill pests. Highly effective attracticides have been developed for the two potato tuber moth species Phthorimaea operculella and Symmetrischema tangolias. Recently, simple plastic barriers proved effective at protecting potato fields from migrating Andean potato weevils (More information).

Participatory research and training

In participatory on-farm research new technologies are tested with farmers and adapted to local conditions. National programs are supported to scale-up new technologies. Development of IPM training materials and the performance of training courses are further important activities of CIP scientists (More information).