Department of Soil Science and Agricultural Chemistry, Institute of Agricultural Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, 221005.
* Present address: National Research Centre for Citrus, Seminary Hills, Nagpur, Maharashtra, 440 006.
Studies on distribution of different forms of Mn, in air-dried and waterlogged sadie and salt affected soils (Natraqualfs) at varying levels of soil pH and response to Mn application by rice and wheat crop in gypsum-amended soils were undertaken. There was 2 times reduction in water soluble Mn, 6.4 fold reduction in exchangeable Mn and 2.6 fold increase in easily reducible Mn with increase in soil pH from 7.2 to 10.3, ECe from 1.46 to 20.82 dS m−1 and ESP from 8.3 to 70.0. Exchangeable Mn, easily reducible Mn and soil pH governed the availability of Mn. DTPA and IN neutral NH4OAc extractable Mn were reduced substantially with increasing pH, ECe, and ESP of salt affected soils. Waterlogging enhanced the availability of Mn in all the soils under investigation. Rice and wheat did not respond to Mn application in a gypsum amended saline sadie soil.
Forms of Mn, waterlogging, gypsum, response saline-sodic soil
