Journal of the Indian Society of Soil Science

Certain elements, which occur in traces in temperate or calcareous soils, are available in excess in humid tropics. Ultisols are low in cation exchange capacity, pH and bases and could be characteristically high in Fe, Mn and Cu that are sensitive to pH as well as variable redox potential. Much of agronomic research has centered on applied elements and the role of native elements in plant growth has not been studied in a comprehensive manner. Moreover, relationship between changing soil properties (as governed by climatic variables) and plant growth is a less known aspect. Hence, an investigation was undertaken to study the relationship between temporal changes in soil properties and plant growth. Changes in soil properties and plant volume of test crop i.e. rubber (during high rain fall period) were the inputs in the path analysis. The variables included in the path model explained 58% the variability. The direct and indirect effects of changes in soil properties on growth were distinct and different. Increase in Fe and Mn had significant negative effect on the plant volume (−0.584* and −0.654*, respectively). The path analysis also indicated the nature of interactions among the soil nutrients and organic matter and their ultimate influence on the growth of rubber plant.