Evaluation of potato nitrogen status based on polyphenol and chlorophyll leaf content

• Autor(a) principal: Coelho, Fabrício Silva
• Data de Publicação: 2012
• Outros Autores: Fontes, Paulo Cezar Rezende, Finger, Fernando Luiz, Cecon, Paulo Roberto
• Tipo de documento: Artigo
• Idioma: por
• Título da fonte: Pesquisa Agropecuária Brasileira (Online)
• Texto Completo: https://seer.sct.embrapa.br/index.php/pab/article/view/11925
• topic: Solanum tuberosum; avaliação em tempo real; balanço nutricional; clorofila; compostos fenólicos; flavonóis; Solanum tuberosum; real‑time evaluation; nutritional balance; chlorophyll; phenolic compounds; flavonols

The objective of this work was to evaluate the effect of N rates on physiological indexes related to nitrogen nutrition in potato, and to verify the possibility of indirectly estimating leaf N contents. Flavonol (FLVI), chlorophyll (CHLI), and the nitrogen balance (NBI) indexes were evaluated, and estimations of leaf N contents were made at 21 and 42 days after emergence using the Dualex leaf‑clip instrument. The experiment was carried out from November 2010 to February 2011, in a randomized complete block design, with five N rates (0, 50, 100, 200, and 300 kg ha-1 of N, applied as urea) at pre‑planting, and four replicates. There was an increase in CHLI and NBI and a decrease in FLVI with the increasing N doses. The indexes determined with Dualex were correlated with N and extractable chlorophyll content in the fourth leaf and with potato tuber yields. Dualex can be used to evaluate N nutritional status in potato plants, and for the prognosis of final tuber yield with readings.