Influence of bio-digester liquid and farmyard manure on growth and yield of rice (Oryza sativa) in Cauvery Command Area of Karnataka

Abstract

A field experiment was conducted during the rainy seasons (kharif) of 2013 to 2016 at Mandya, Karnataka, to study the influence of bio-digester liquid (BDL) and farm yard manure (FYM) on growth and yield of rice (Oryza sa- tiva L.) in Cauvery Command Area of Karnataka. The experiment was laid out in randomized complete block de- sign with 3 replications. Ten treatments comprising different levels of farmyard manure (7.5, 10.0 and 12.5 t/ha) and bio-digester liquid manure equivalent (75, 100 and 125 kg N/ha) and their combinations were compared with the control (no manures). Application of farmyard manure 12.5 t/ha + bio-digester liquid manure equivalent to 125 kg N/ha in 2 splits recorded significantly higher grain yield and net return/rupee invested ( 4.90 t/ha and 1.52 re- spectively) compared to the other applications. However, it was at par with application of farmyard manure 12.5 t/ ha + bio-digester liquid equivalent to 100 kg N/ha in 2 splits (4.7 t/ha and 1.53 respectively). This increased yield in above treatments was mainly owing to increased availability of soil N (296.3 kg/ha), P O (37.8 kg/ha) and K O 2 5 2 (185.6 kg/ha). There was an increasing trend in the soil chemical properties, viz. soil pH (7.58), electrical conduc- tivity (0.401 dS/m) and organic carbon content (0.41%) at the end of the fourth crop cycles as compared to initial level (organic carbon content: 0.345%, soil pH 6.85, electrical conductivity: 0.338 dS/m).