méthode biologique de lutte contre les nuisibles (1) lutte antiparasitaire (1) papier (1) innovation (1) pièce d'exposition (1) conseil (1) prélèvement (1) Lettonie (1) Development (1) Specimens (1) Interviews (1) Forms (1) Balances (Weighing instruments) (1) Specialists (1) Teaching (1) Social sciences (1) Pests--Control (1) Pests--Biological control (1) Paper (1) Non-formal education (1) New and old (1) Learning (1) Interviews (1) Instruction (1) Farmers (1) Exchange (1) Equilibrium (1) Education (1) Driving of horse-drawn vehicles (1) Drawing (1)