Leaf area index of potato (Solanum tuberosum L.) crop under three nitrogen fertilization treatments

Abstract

Nitrogen fertilization has considerable effects on growth and yield of potato crop. Leaf expansion is one of the most important growth parameters that can be used to optimize nitrogen fertilization management in agroecological practices. We evaluated the effect of nitrogen fertilization on the leaf area index (LAI) of potato crop during different phenological stages by two different methods. Experimental plots were established in a randomized block design with the following treatments: no nitrogen supply (0-N), 133 kg N ha-1 (133-N), and 400 kg N ha-1 (400-N), using the Granola variety, at the Andes region, Merida city, Venezuela. We measured leaf area at the main phenological stages of the crop using a plant canopy analyzer. LAI showed significant differences among treatments and phenological stages, except during the emergence stage. The maximum LAI values were obtained 55 days after emergence: 400-N (1.42±0.16) > 133-N (0.92±0.21) > 0-N (0.34±0.08). Nitrogen fertilization had a significant effect on the development of LAI in potato crop along its different phenological stages.