Tuber yield prognosis model and agronomic nitrogen use efficiency of potato cultivars

Abstract

Adjusting nitrogen (N) fertilization rates to crop requirements optimizes N efficiency and reduces environmental pollution. In accordance with such precision agriculture, methods facilitating rapid and simple real-time crop yield prognostication are desirable. The aims of this study are to establish a prognostic model for tuber yield; early characterization of a properly N-nourished plant and to determine the N use efficiency by the Asterix and Atlantic potato cultivars. In two separate experiments, on for each cultivar, five pre-planting N fertilization rates (0, 50, 100, 200, and 300 kg ha-1) were evaluated. A randomized complete block design with four replicates per experiment was utilized. Variable chosen for early evaluation, 21 days after emergence, were categorized into four named groups. Group one, linked to chlorophyll (SPAD index and total fourth leaf chlorophyll concentration). Group two, concerning with physiological indexes (leaf, fourth leaf, stem, and shoot dry matter; fourth-and whole-plant leaf area; fourth leaf and plant specific leaf area; and leaf area ratio). The third group linked to fourth leaf N indexes (N concentration per unit dry matter and per unit leaf area, and total N content). The fourth group referring to N use efficiency (fourth leaf N use efficiency and agronomic N use efficiency). For both cultivars, there are a significant positive correlation between tuber yield and physiologic and N indexes, while there is a significant negative correlation between tuber yield and N use efficiency. Regression models utilising the SPAD index as an independent variable are effective in predicting the marketable tuber yield of potato plants, and have the added advantage of real-time determination of the SPAD index in relationship a another methods.

Response of Potato (Solanum tuberosum L.) Cultivars to Different Levels of Nitrogen

“…According to increase in nitrogen dose, the yield of tubers also increases but the rate of difference in yield per dose increases with less pace as nitrogen dose advances. Same pattern was also observed by Fontes et al, (2016). Plant metabolic factors for nitrogen use efficiency maximization differ at high and low nitrogen availability, indicating great potential for nitrogen use efficiency improvement (Xu et al, 2012).…”

Índices de nitrogênio e modelo para prognosticar a produção de tubérculos de batata

“…Tabela 2: Coeficientes de correlação linear entre os índices SPAD, clorofila (CHL), índice balanço de N (NBI) e flavonoides (FLV) e as características representativas do estado de N da planta, teor de N na seiva do pecíolo (TNSP), teor de N da matéria seca (TNMS) e quantidade de N acumulada da matéria seca (QNA) da quarta folha da batata, determinados aos 10 e 21 dias após a emergência (DAE), para os cultivares Ágata e Asterix Em outra situação experimental, com base na leitura SPAD, o modelo proposto para estimar a produtividade comercial de tubérculos (PC) do cultivar Asterix, em t/ha, foi PC = 13,74 + 0,53 SPAD (Fontes et al, 2016). Modelos para estimar a produtividade das culturas, com base na leitura SPAD, têm sido propostos (Le Bail et al, 2005;Yildirim et al, 2010;Islam et al, 2014).…”

The Impact of Fertilization Regime on the Crop Performance and Chemical Composition of Potato (Solanum tuberosum L.) Cultivated in Central Greece

“…Lately, there is an increased interest from potato growers in defining the optimal fertilization regimes in order to maximize total yield, while at the same time minimizing the production cost and maintaining high quality [3,4]. Optimizing the efficiency of nitrogen use has been suggested through various methods with the most common practice being the replacement of the single rate nitrogen fertilization through base dressing by multiple rates during the cultivation period through side dressings, depending on plant requirements and growth stage [5,6].…”