Effect of organic matter and bio-fertilizers on growth and yield of large cardamom (Amomum subulatum Roxb.) in Kalimpong district of West Bengal

To evaluate the effects of organic matters like farmyard manure and vermicompost either alone or in combination with one of the two bio-fertilizers consortium I and consortium - II, a field experiment was carried out from September 2019 to September 2022 on large cardamom variety Varlangey in farmer’s field at Lower Beong busty, Gitdubling in Kalimpong District, West Bengal, India. The experiment had eight treatments are T₁ Farmers practice (Farm Yard Manure (FYM) @ 15 t/ha/year), T₂ FYM @ 20 t/ha/year,T₃ Vermicompost @ 8 t/ha/year, T₄ Vermicompost @ 10 t/ha/year, T₅ FYM @ 15 t/ha/year + Bio-fertilizers-I (Azospirillium + Azotobacter + PSB + Trichoderma + Pseudomonas) @ 10 g each/clump, T₆ FYM @ 20t/ha/year + Bio-fertilizers-II (Azospirillium + Azotobacter + VAM + Trichoderma +Pseudomonas) @ 10 g each/clump,T₇ Vermicompost @ 8 t/ha/year + Bio-fertilizers-I (Azospirillium + Azotobacter + PSB + Trichoderma + Pseudomonas) @ 10 g each/clump, T₈ Vermicompost @ 10 t/ha/year + Bio-fertilizers-II (Azospirillium + Azotobacter + VAM + Trichoderma +Pseudomonas) @ 10 g each/clump.replicated thrice and laid out in randomized block design. Statistical analyses revealed that all the treatments had significant effects on the morphological characters observed up to 1080 days after planting. Treatment (T₈) with vermicompost @10t/ha/yr + bio-fertilizers consortium -II (Azospirillium +Azotobacter + VAM + Trichoderma + Pseudomonas @ 10 g each/clump resulted in highest plant height (202.20 cm), maximum number of leaves tiller clump^-1 (11.07), number of young tillers clump^-1 (11.60), spikes bunch^-1 (15.87), spikes plot^-1 (190.40), capsule spike^-1 (11.80), number of capsule Plot^-1 (2246.72), test weight fresh and dry (93.75 gm and 17.33 gm), yield of the fresh and dry weight of the seeds (2.72 kg plot^-1 and 1.44 kg plot^-1), fresh and dry yield attributes (705.19 kg ha^-1 and 373.33 kg ha^-1), cost of cultivation (Rs. 147434), gross return (Rs. 317595) net return (Rs. 170161) and benefit cost ratio was (2.16:1) followed by treatment (T₇) with vermicompost @8t/ha/yr + (Azospirillium +Azotobacter + PSB + Trichoderma + Pseudomonas) @ 10 g each/clump over other treatments. However, minimum was observed in farmers practice (farm yard manure @ 15 t/ha/yr).