National Academy of Agricultural Sciences (NAAS)
|
PRINT ISSN : 2319-7692
Online ISSN : 2319-7706 Issues : 12 per year Publisher : Excellent Publishers Email : editorijcmas@gmail.com / submit@ijcmas.com Editor-in-chief: Dr.M.Prakash Index Copernicus ICV 2018: 95.39 NAAS RATING 2020: 5.38 |
Iron toxicity and acidity are the major constraints in the laterite derived paddy soils of Kerala. More than 90 % of the midland lateritic rice soils in the northern part of Kerala are strongly acidic in reaction with pH values in the range of 4.5 to 5.5. The content of 0.1 N HCl extractable Fe in soil varied from 52.21 – 414.9 mg kg-1 and more than 50 % of the rice soils showed iron toxicity problem (> 250 mg kg-1 of available iron). A field experiment conducted to evaluate the effectiveness of non conventional liming materials like phosphogypsum, limestone powder and their blends in managing iron toxicity and soil acidity for enhancing the yield of rice in comparison to conventional shell lime revealed that all the liming treatments significantly reduced the soil acidity and iron toxicity problem. The highest pH of 5.33 was recorded in the treatment receiving shell lime@ 600 kg / ha. The exchangeable calcium content in soil increased from 749 mg kg-1 in control to 909 mg kg -1 in phosphogypsum applied treatment. The 0.1 N HCl extractable iron content in soil was reduced from 511 mg kg -1 in control to 353 mg kg-1 in lime stone powder 300 kg ha-1 + phosphogypsum 300 kg ha -1 applied treatment. The availability of nutrients were the highest in treatment receiving lime stone powder 300 kg ha-1 + phosphogypsum 300 kg ha-1. The available Mn and exchangeable Al were found to decrease with the application of liming materials. The highest grain yield of rice (5.73 t ha-1) was obtained in the combined application of lime stone powder 300 kg ha -1 + phosphogypsum 300 kg ha -1.
Citations |
 |
 |
 |
 |
