Chemical Properties of Soil and Yield of Sunflower as Influenced by Application of Saline Water and Gypsum.
J.R. Kadam, Mahatma Phule Krishi Vidyapeeth, Dept of Agri. Chem. & Soil Science, Rahuri, 413722, India and AM Deokar, Dept of Agri Chem & Soil Sciences, Mahatma Phule Krishi Vidyapeeth, Rahuri, 413 722, India.
A field experiments was conducted at MPKV., Rahuri to study the effect of saline water and gypsum on chemical properties of soil. The treatments S1, S1, S2 and S3 in which saline water and canal water used for irrigation to sunflower and gypsum was applied as an amendment. The salinity of all canal water was 0.39 dSm-1 (treatment S0) and that of all saline water the ECsw was 2.20 dSm-1 (treatment S1). The salinity levels of treatment S1 and S2 were made by conjuctive use of 1 saline water followed by 1 canal water and 2 saline water followed by 1 canal water respectively. Gypsum was applied @ 923 g/plot in S1 and S2 treatment. The soil pH, ECe, Na+, Mg2+ and SAR of saturation paste extract increased under saline water irrigation treatment while Ca2+ content decreased. The soil pH increased from 8.09 to 8.49, ECe 0.92 to 1.86 dSm-1, Na 17.93 to 20.2 meL-1, Mg 6.53 to 18.29 meL-1 and SAR 2.21 to 4.69 meL-1. The Ca2+ content decreased from 19.03 to 18.10 meL-1. Soil pH, ECe, Na+, Mg2+ and SAR of saturation paste extract decreased while Ca2+ content increased with application of gypsum. Soil pH decreased from 8.09 to 7.82, ECe 0.92 to 0.71 dSm-1, Na 7.93 to 7.25 meL-1, Mg 6.53 to 5.88 meL-1 and SAR 2.21 to 2.03 meL-1. The Ca2+ content increased from 19.03 to 19.49 meL-1. Soil crust strength was increased from 1.89 to 2.16 kg/cm2 with increase in the salinity of irrigation water from 0.39 to 2.20 dSm-1. Application of gypsum decreased the soil strength from 1.89 to 1.61 kg/cm2. The yield of sunflower was decreased significantly from 1028 kg to 723 kg ha-1 with increase in the salinity of irrigation water. The highest sunflower yield of 1437 kg ha-1 was observed under treatment S2 where gypsum was applied with saline irrigation water.