Conservation Agriculture System Impact on Soil Nutrient Status in Eastern Dry Zone of Karnataka, India
Devappa *
Department of Soil and Water Engineering, College of Agricultural engineering, University of Agricultural Science, GKVK, Bengaluru-560065, Karnataka, India.
Rajashekarappa, K. S.
Department of Soil and Water Engineering, College of Agricultural engineering, University of Agricultural Science, GKVK, Bengaluru-560065, Karnataka, India.
Mudalagiriyappa
AICRP for Dry land Agriculture, University of Agricultural Science, GKVK, Bengaluru-560065, Karnataka, India.
Devaraj, K.
AICRP for Dry land Agriculture, University of Agricultural Science, GKVK, Bengaluru-560065, Karnataka, India.
Latha, H. S.
AICRP for Dry land Agriculture, University of Agricultural Science, GKVK, Bengaluru-560065, Karnataka, India.
*Author to whom correspondence should be addressed.
Abstract
Tillage is the physical manipulation of soil into optimum conditions, which enhance the soil health for better crop productivity. A field investigation was carried out to evaluate conservation agriculture effect on soil nutrient conservation and set up in spilt plot design. Zero tillage (M3) witnessed significantly (P<0.05) greater nitrogen availability (288.17, 251.39 and 239.70 kg ha-1), K2O (229.04, 209.80 and 193.73 kg ha-1) than conventional tillage (M1) at soil depths 0-7.5, 7.5-15 and 15-30 cm, respectively. In green manuring practices, horse gram (C3) recorded OC (0.53, 0.51 and 0.47 %), available sulphur (23.38, 20.61 and 18.10 mg kg-1) followed by sun hemp. The interaction combination of M3C3 recorded highest soil nutrient status. Significantly lowest microbial population were found in M1, was due to faster decomposition organic matter resulted in unfavourable condition for survival. Overall adopting M1 alone (1 Ploughing + 2 harrowing + 1 intercultural operation) adversely affect soil health.
Keywords: Conservation tillage, harrowing, green manuring, nitrogen, microbial population, soil health, pigeonpea