MCQs Soil Science-58 Posted on November 30, 2025November 30, 2025Author agropublishers 0 MCQs Soil Science-58 1. A higher C:N ratio in residues leads to ———- Increased humus decay Nitrogen immobilization Nitrogen mineralization Faster decomposition 2. Root exudates promote microbial growth in the rhizosphere True False 3. Rhizobia, bacteria live in the roots of leguminous plants, play a crucial role in _________ Nitrogen fixation Nutrient uptake Pathogen defense Water absorption 4. Nitrogen is usually the most limiting nutrient in crop production False True 5. Which fraction of soil organic matter decomposes fastest? Humus Fresh residues Humic acid Humin 6. ————– are the most efficient and dominant organisms in decomposing lignin-rich materials like wood Actinomycetes Fungi Bacteria Algae 7. Humus increases soil fertility by improving ————- Drainage Cation Exchange Capacity Soil aeration All of these 8. Clay soils generally have higher fertility than sandy soils True False 9. A productive soil under one crop may ———- Be unproductive for another Be always equally productive for all crops Never change in productivity Lose fertility instantly 10. Soil enzyme activity decreases with heavy metal pollution False True Loading … Question 1 of 10
