Maize dry matter production and macronutrient extraction model as a new approach for fertilizer rate estimation

Abstract

Decision support for nutrient application remains an enigma if based on soil nutrient analysis. If the crop could be used as an auxiliary indicator, the plant nutrient status during different growth stages could complement the soil test, improving the fertilizer recommendation. Nutrient absorption and partitioning in the plant are here studied and described with mathematical models. The objective of this study considers the temporal variation of the nutrient uptake rate, which should define crop needs as compared to the critical content in soil solution. A uniform maize crop was grown to observe dry matter accumulation and nutrient content in the plant. The dry matter accumulation followed a sigmoidal model and the macronutrient content a power model. The maximum nutrient absorption occurred at the R 4 growth stage, for which the sap concentration was successfully calculated. It is hoped that this new approach of evaluating nutrient sap concentration will help to develop more rational ways to estimate crop fertilizer needs. This new approach has great potential for on-the-go crop sensor-based nutrient application methods and its sensitivity to soil tillage and management systems need to be examined in following studies. If mathematical model reflects management impact adequately, resources for experiments can be saved.

Effect of maturity stage at harvest on the ensilability of maize hybrids in the early and late FAO classes, grown in areas differing in yield potential

“…The whole maize plant content of DM and WSC at harvest was in agreement with data reported in the literature (Ferraretto et al, ; Hatew, Bannink, van Laar, de Jonge, & Dijkstra, ; Lynch, O'Kiely, & Doyle, ) for whole maize crops intended for the production of maize silage. The highest DM and WSC content of hybrids belonging to class 200 was likely due to their higher radiation use efficiency that led to a higher speed of the carbohydrate synthesis before flowering (Andrieu et al, ) and in the starch deposition during the period of grain filling (Martins et al, ), as was also reported by Millner, Vill Aver, and Hardacre () and Lynch et al () who found higher percentages of grain in the early‐maturing hybrids, compared with the late‐maturing hybrids.…”

“…The higher DM and the lowest WSC content of plants grown in the low yield area was expected because the non‐optimal conditions of soil texture, hydration and presence of nutrients, led to a slower maturation of plants, affecting the content of cell walls, carbohydrate synthesis and grain development (Andrieu et al, ). As the plant grows, it increases its DM (Hatew et al, ; Martins et al, ), along with its crude protein, lignin (Ferraretto et al, ) and starch content. Starch deposition during grain filling results from the conversion of WSC, which includes the glucose synthesised during photosynthesis (Lynch et al, ).…”

“…The whole maize plant content of DM and WSC at harvest was in agreement with data reported in the literature (Ferraretto et al, 2015;Hatew, Bannink, van Laar, de Jonge, & Dijkstra, 2016;Lynch, O'Kiely, & Doyle, 2013) for whole maize crops intended for the production of maize silage. The highest DM and WSC content of hybrids belonging to class 200 was likely due to their higher radiation use efficiency that led to a higher speed of the carbohydrate synthesis before flowering (Andrieu et al, 1993) and in the starch deposition during the period of grain filling (Martins et al, 2017), as was also reported by Millner, Vill Aver, and Hardacre (2005) The higher DM and the lowest WSC content of plants grown in the low yield area was expected because the non-optimal conditions of soil texture, hydration and presence of nutrients, led to a slower maturation of plants, affecting the content of cell walls, carbohydrate synthesis and grain development (Andrieu et al, 1993). As the plant grows, it increases its DM (Hatew et al, 2016;Martins et al, 2017), along with its crude protein, lignin (Ferraretto et al, 2015) and starch content.…”

“…The highest DM and WSC content of hybrids belonging to class 200 was likely due to their higher radiation use efficiency that led to a higher speed of the carbohydrate synthesis before flowering (Andrieu et al, 1993) and in the starch deposition during the period of grain filling (Martins et al, 2017), as was also reported by Millner, Vill Aver, and Hardacre (2005) The higher DM and the lowest WSC content of plants grown in the low yield area was expected because the non-optimal conditions of soil texture, hydration and presence of nutrients, led to a slower maturation of plants, affecting the content of cell walls, carbohydrate synthesis and grain development (Andrieu et al, 1993). As the plant grows, it increases its DM (Hatew et al, 2016;Martins et al, 2017), along with its crude protein, lignin (Ferraretto et al, 2015) and starch content. Starch deposition during grain filling results from the conversion of WSC, which includes the glucose synthesised during photosynthesis (Lynch et al, 2013).…”

Macronutrients Absorption and Dry Matter Accumulation in Grain Sorghum

“…Due to the maximum absorption point in the plants, the crop requirement for nutrients cannot be inferred only from the total extraction. It is necessary to study the nutrient uptake in function of time, to predict how, when and what amount of fertilizer should be applied (Martins et al, 2017).…”