Modeling rice seedling emergence and growth under tillage and residue management in a rice-wheat system on a Vertisol in Central India

Tillage and residue management practices are known to affect seedling emergence and growth. However, information on direct seeded rice (Oryza sativa L.) in rice-wheat (Triticum spp.) cropping system is lacking. Thus a study was undertaken under different tillage (conventional and zero tillage) and residue (residue-retained and removed) management options on rice seedling emergence and growth in rice-wheat system on a Vertisol of Central India. Seedling emergence was greater in residue removed plots compared to residue-retained one. Prediction of rice seedling emergence with the France and Thornley [Mathematical Models in Agriculture and Related Sciences, Butterworths, London, 1984] model and growth by the Logistic and Gompertz model, and Monomolecular model were also attempted. Emergence indicators showed that seedling emergence of rice was favored more by conventional tillage than zero tillage in wheat. Of the three models tested, the Gompertz model gave the best fit. The effect of tillage and residue of wheat on the estimated parameters of the models were also studied. (C) 2003 Elsevier B.V. All rights reserved.