Chemical control 18 Biological Control 13 Biological control 13 Natural enemies 12 Pesticides and Drugs; Control, (New March 2000) 11 Plant Pests, (New March 2000) 10 Horticultural Crops, (New March 2000) 9 Integrated Pest Management 9 Pest control 9 Plant pests 9 Cultural control 7 Environmental Pest Management 7 Integrated control 7 Insects 6 Plant diseases 6 Plant pathogens 6 Taxonomy 6 Taxonomy and Evolution 6 Fungi 5 Insect pests 5 Integrated pest management 5 Nematoda 5 Plant disease control 5 Plant parasitic nematodes 5 Behaviour (Wild Animals), (New March 2000) 4 Biological control agents 4 Field Crops, (New March 2000) 4 Fungal diseases 4 Insect control 4 Nematode control 4