Improvement in Soil Productivity with Long-term Lantana (Lantana camara L.) Additions in Rice-wheat Cropping – II. Effect on Crop Yields and Zinc Uptake

Long-term lantana additions and N applications individually, increased significantly rice and wheat yields and Zn uptake. The continuous addition of lantana at the rate of 20 t ha⁻¹ (fresh weight) for seven years resulted in net savings of 50 per cent of the recommended dose of N in rice and wheat grown in sequence. Among various soil Zn fractions, first three viz. non-specifically adsorbed exchangeable (Zn I), specifically adsorbed exchangeable (Zn II) and organically bound (Zn III) emerged as the most important Zn fractions contributing to Zn nutrition of rice and wheat. The DTPA extractant was effective in extracting Zn from these three soil Zn fractions and thus significantly correlated with all the plant growth parameters of rice and wheat.