agriculture forestry 80 agrochemistry 68 soil science 54 chemistry 43 permanently sustainable development 39 economy 37 more ... fertilizers 32 plant production 32 agricultural engineering 32 animal husbandry 30 history 30 hydromeliorations 28 agricultural economics 27 environment 27 feeds 24 plant breeding 24 plants 23 botany 22 statistics 21 biotechnologies 20 plant physiology 20 land 20 soil protection 19 yields 19 agricultural machinery and equipment 19 animal production 19 fertilization 18 economizing 18 microbiology 16 less ...