Rainfed rice - IRRI books - International Rice Research Institute

Dealing with Decline in Soil Fertility and Land Productivity
Alleviate soil acidity Yield trend with different levels of lime application
Soil acidity and sometimes
(with recommended dose of NPK) in farmers’ fields in
trials conducted by CRRI, Cuttack
aluminum (Al) toxicity occur in
rainfed uplands. To overcome these
problems, apply half of the lime
requirement (LR) recommended to
the soil, two to three weeks before
sowing/transplanting in alternate
years. Deep plowing up to 15 cm
depth helps in thorough mixing of
lime in the soil and also inactivates
Al.
Zinc application
With intensive rice cultivation, soil fertility is declining and Zn deficiency
has been widely reported. In Zn-deficient soils, apply 20-25 kg zinc
sulphate (ZnSO 4 ) or 5 kg Zn-EDTA/ha before seeding or transplanting.
Alternatively, dip the roots of rice seedlings in 0.5% ZnSO 4 or zinc oxide
(ZnO) solution overnight before planting. Do not mix Zn with phosphatic
fertiliser.
Land management practices
The land should be levelled properly before sowing/planting rice to avoid
soil erosion and runoff.
In sloping uplands, soil and water conservation methods such as contour
bunding, contour cultivation and planting and deep tillage should
be adopted.
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