Influence of nitrogen fertilizer and cattle manure on the vegetative growth and tuber production of potato

ABSTRACT: In order to study the Influence of nitrogen (N) fertilizer and cattle manure on the vegetative growth and tuber production of potato, a field experiment was conducted in April 2008 in Iran, with factorial arrangement based on randomized complete block design (RCBD) with three replications. Treatment groups consisted of the administration of nitrogen fertilizer at three concentration levels (50, 100 and 150 Kg h-1) and cattle manure at four levels (5, 10, 15 and 20 tons h-1). From 45th to 105th day after emergence (DAE), plant height and Leaf Area Index (LAI) were measured every 15 days.Furthermore, at the end of the growth season, tuber yield was calculated. Results showed that, in all sampling times, plant height and LAI were increased significantly by increasing N fertilizer. In addition, the LAI showed significant differences in relation to different concentrations of cattle manure. In the same way, the plant heights showed a significant rise with the increasing concentrations of cattle manure at the 45th, 60th, 75th and 90th DAE. The integrated use of nitrogen fertilizer and cattle manure increased LAI significantly (at the 45th, 75th and 90th DAE).Also, the combined effects of cattle manure and N fertilizer on plant heights were significant at the 60th, 75th, 90th and 105th DAE. Furthermore, results of tuber yield showed that, Nitrogen fertilizer, Cattle manure and their combination had a highly significant effect on tuber yield. In this experiment maximum amount of tuber yield (36.8 tons ha-1) was obtained by 20 tons ha-1 Cattle manure+150 kg N ha-1