Effect of organic fertilizer and microbial inoculants on soil biological properties and yield of scented rice (Oryza sativa L.)

Abstract

A field experiment was conducted at Research farm of Bihar Agricultural University, Sabour (longitude 87^o2’42”East and latitude 25^o15?40? North at an altitude of 46 meters above mean sea level) with Katarni rice cv Bhagalpur Katarni during kharif season of 2017. The experiment with ten treatments was laid out in Randomized  block design (RBD)  with three  replications. Results revealed that among all the applied organic treatments the maximum microbial population viz., Bacteria, Actinomycetes, Fungi, Azospirillum, PSB and KSB (71.66, 27.33,  57.66, 43.66, 63.00 and 47.66 cfu × 10⁵ g^-1 oven dry soil) were recorded with the application of treatment T₅ {(75 % N (FYM) basal + 25 % N (V/C) at 25 DAT + Azospirillum  @ 5 kg ha^-1  + PSB @ 5 kg ha^-1 + KSB @ 5 kg ha^-1)} at panicle initiation stage  and similar trend were obtained at harvesting stage. Application of the same treatment significantly increased dehydrogenase activity by 81.62%, 10.80%, 24.86%, 15.66%, 17.83% and 18.91% when compared with application of T₁ (RDF), T₃ {(100 % N FYM) as basal)}, T₇ {(100 % N (GM)}, T₈ {(50 % N (GM) + 50 % N (V/C) at 25 DAT)}, T₉ {(75 % N (GM) + 25 % N (V/C) at 25 DAT + Azospirillum @ 5 kg ha^-1 + PSB @ 5 kg ha^-1 + KSB @ 5 kg ha^-1)} and  T₁₀ {(75 % N (GM) + 25 % N (V/C) at 25 DAT + Panchagavya on foliar application )}, respectively. Among all organic treatments the maximum grain yield of paddy (27.39 q ha^-1) was recorded in treatment T₅ {(75 % N (FYM) basal + 25 % N (V/C) at 25 DAT + Azospirillum  @ 5 kg ha^-1  + PSB @ 5 kg ha^-1 + KSB @ 5 kg ha^-1)}. Among all the organic inputs and microbial inoculants, the combined application of 75 % N (FYM) basal + 25 % N (V/C) at 25 DAT + Azospirillum @ 5 kg ha^-1 + PSB @ 5 kg ha^-1 + KSB @ 5 kg ha^-1 was found to be effective in modifying the soil microbial population and microbial community structure and grain yield of scented rice.