History 306 Imperialism 241 Crop improvement 147 Philosophy 99 History and criticism 91 Imperialism in literature 75 Plant Propagation 71 India 69 Economics 62 Women 61 English literature 58 Social aspects 58 Politics and government 57 Colonies in literature 53 Social conditions 51 Management 50 Agriculture 49 Biotechnology 49 Education 48 Plant Biotechnology 47 Plant breeding 46 Agronomy 45 Capitalism 43 Postcolonialism 43 Globalization 41 Research 41 Colonies 39 Mathematics 39 Plant Breeding and Genetics 39 Economic development 38