EVALUATION OF ORGANIC AMENDMENTS IN ALLEVIATING THE ADVERSE EFFECT OF WATER DEFICIT STRESS ON SOYBEAN

To assess the impact of different soil amendments in alleviating the adverse effects of water deficit stress on soybean, a field experiment was conducted at the Crop Physiology and Ecology research field of Hajee Mohammad Danesh Science and Technology University, Dinajpur during November 2020 to June 2021. The experiment was laid out in a randomized complete block design (RCBD) with three replications. The treatments were, T₁- Recommended dose of fertilizer (RDF) in well water condition, T₂- RDF in water stress condition, T₃- Biochar (10 t ha^-1) + RDF in water stress condition, T₄- Biochar (20 t ha^-1) + RDF in water stress condition, T₅- Poultry litter based compost (5 t ha^-1) + RDF in water stress condition, T₆- Poultry litter based compost (10 t ha^-1) + RDF in water stress condition, T₇- Cattle manure ( 25 t ha^-1) + RDF in water stress condition, T₈-  Cattle manure ( 50 t ha^-1) + RDF in water stress condition, T₉- Vermicompost (2.5 t ha^-1) + RDF in water stress condition, T₁₀- Vermicompost (5.0 t ha^-1) + RDF in water stress condition,  T₁₁- Humic acid (2.5 kg ha^-1) + RDF in water stress condition and T₁₂- Humic acid (5.0 kg ha^-1) + RDF in water stress condition. Additional application of biochar, poultry litter based composed, cattle manure, vermicompost and humic acid improved plant height and leaves plant^-1, increased the greenness of leaf, improved leaf water status and relative leaf water content, increased leaf proline content and total plant dry weight, improved seed yield in different magnitude under water stress condition compared to application of recommended inorganic fertilizer alone. Additional application of biochar @ 20 t ha^-1, poultry litter based compost @ 10 t ha^-1, cattle manure @ 50 t ha^-1 and humic acid @ 2.5 kg ha^-1 performed better in alleviating the adverse effect of water deficit stress on soybean.