Statistics 18 Genetics 15 Plant breeding 13 Soil science 13 Entomology 9 Microbiology 9 Mycology 9 Probability 9 Fungi 8 Irrigation 7 Sampling 7 Experimental design 6 Insects 5 Soil microbiology 5 genetics 5 Correlation 4 Dairy cattle 4 Enzymology 4 Heredity 4 Metabolism 4 Mutation 4 Organic chemistry 4 Regression 4 Variance 4 fungi 4 hatchability - chicken and turkey eggs 4 mycology 4 plant breeding 4 soil science 4 statistics 4