Crop yields Congresses 14 Crops 14 Agricultural productivity 11 Mathematical models 10 Physiology 9 Crops and climate 7 plus ... Fertilizers 7 Agriculture 6 Rice 6 Crops and water 4 Field crops 4 Food crops 4 Agricultural estimating and reporting 3 Climatic changes 3 Cotton 3 Economic aspects 3 Farm management 3 Growth 3 Arid regions agriculture 2 Crops and soils 2 Farm produce 2 Fertilization of plants 2 Fertilizers and manures 2 Irrigation farming 2 Physiological effect 2 Plant physiology 2 Production planning 2 Soil productivity 2 Statistics 2 moins ...