Abstract

Proper crop rotation might help to conserve soil fertility among small scale potato farmers in Kenya. A study was carried out at KARI Tigoni station between April 2007 and May 2010 to evaluate the effect of crop rotation on soil pH and macro nutrient levels. Rotations involved maize, potatoes and cabbages. Results showed that, soils at KARI Tigoni station are generally acidic with pH ranging from 4.3 (extreme acidity) to 5.59 (medium acidity). Cultivation reduced pH further probably due to increased organic matter decomposition. Percent organic carbon was low and was significantly (P = 0.05) increased by the rotation. Percent total nitrogen was adequate for potato production. Phosphorus was generally low. Proper crop rotation should be employed which should include a legume. This study should be carried out over a longer period of time to get more comprehensive results.

Key words: Crop rotation, soil pH, soil macronutrients, potato production, KARI Tigoni.