Effect of inorganic fertilizer and biofertilizer (Azotobacter sp.) on the growth attributes of Sesamum indicum L. under old alluvial soil, West Bengal

A field experiment was conducted to determine the combined effects of biofertilizer and inorganic fertilizer on sesame (Sesamum indicum) under old alluvial soils of West Bengal. Five recommended dose of fertilizer treatments (T₁ - full inorganic fertilizer; T₂ - ¾ inorganic and ¼ biofertilizer; T₃ - ½ inorganic and ½ biofertilizer; T₄ - ¼ inorganic and ¾ biofertilizer; T₅ biofertilizer only) were used for field study in randomized block design with three replicates. Plant morphological traits (root and shoot length, fresh and dry weight, leaf area), chlorophyll, sugar, crop growth rate (CGR) and net assimilation rate (NAR) were measured. Results showed that higher percentage of biofertilizers considerably enhanced the plant height, biomass, leaf area index and plant yield. The morphological attributes revealed that the treatments (T₄ and T₅) exhibited greater root length compared to the other treatments for both 50 days and 74 days after sowing. The treatments T₃ and T₅ showed higher root dry weight after 74 and 50 days of sowing, respectively. In addition, T₂ and T₅ treatments exhibited higher biomass for 74 and 50 days, respectively. The combined use of inorganic and biofertilizers promoted growth, buildup of dry matter and improved the physical state of the soil by increasing the soil fertility. Therefore, both inorganic and biofertilizers can be used in combination for growing sesame in West Bengal's old alluvial soils.