Speaker
Description
Introduction:
Oil palm (Elaeis guineensis Jacq.) stands as the leading global oil-producing crop, representing a production of approximately 75 Mt y-1 (FAOSTAT). However, the present challenge of oil palm cultivation is to meet global food demands while respecting the environment. To achieve this, it is crucial to control the use of fertilizers, in particular potassium (K). Potassium is the most critical nutrient in palm oil production since oil palm growth and yield are highly dependent on K fertilization (1,2). In fact, oil palm is a highly K-demanding species, not only due to nutrient requirements for bunch production but also because it is typically cultivated in naturally K-deficient regions. Additionally, substantial amounts of K are removed during fruit bunch harvesting, leading to a loss of up to 75% of the K fertilization input (2). As a result, heavy K fertilization is employed, costing about $1 billion globally.
Quite understandably, intense efforts have been devoted to enhancing fertilization strategies and exploring precision agriculture to accurately monitor K needs.
Presently, K fertilization decisions are based on leaflet K content using the LD (leaf diagnosis) method (3), but its technical limitations have led to a search for better monitoring methods. Metabolomics and machine learning of metabolic signatures emerge as promising tools, opening avenues for precision agriculture in oil palm industry. Our recent studies utilizing potassium chloride (KCl) as a potassium source reveal metabolic traits linked to K availability (1,4,5). However, monitoring K fertilization stays challenging due to its interdependence on other nutrients (6)
Here, we are conducting an analysis of leaf metabolism coupled to elemental analyses, using oil palm trees of two commercial varieties, Eka1 and Eka2, grown in the field in North Sumatra (Indonesia). Our specific objective is to apply different K sources with varied concentrations to explore metabolic markers and study nutrient interactions related to different K sources, which will allow us to monitor K fertilization with higher accuracy. Also, it will allow us to assess the robustness of metabolic traits associated with K availability.
Materials and Methods:
The field is located at the SMARTRI station (North Sumatra, Indonesia) and sampling will be carried out in June 2024 and January 2025. Overall, 126 oil palm trees will be studied. They belong to two varieties: Eka1 and Eka2. Eka1 and Eka2 have been chosen here since they are two very common varieties used in oil palm agroforestry. Oil palm trees will be subjected to four levels of potassium fertilization with 7 K sources applied proportionally with growth (Fig1.B, D). Leaflets will be used for analyses and sampled at B point (Fig1.C).
Gas chromatography coupled to mass spectrometry (GC–MS) analyses will be carried out as in (1). 1H-NMR analysis will be performed on a Bruker Advance 600 MHz spectrometer. Mineral content analysis will be done as well. Then multivariate analysis of metabolomics data will be carried out.
Results and Discussion:
The study aims to explore the metabolomic response of palm trees to various potassium sources and examine the antagonistic and synergistic effects between nutrients. Additionally, it seeks to evaluate how different potassium (K) sources influence the precision of leaf potassium status assessment. Furthermore, we aim to identify potential metabolomic markers that could serve as universal indicators of potassium levels, with the ultimate goal of optimizing LD technique or substituting it with more efficient metabolic tools.
References:
- Cathleen Mirande-Ney. Effects of Potassium Fertilization on Oil Palm Fruit Metabolism and Mesocarp Lipid Accumulation. 2019;
- R.H.V. Corley, P.B. Tinker. The Oil Palm. 2003.
- Chapman GW, Gray HM. Leaf Analysis and the Nutrition of the Oil Palm (Elaeis guineensis Jacq.). Annals of Botany. oct 1949;13(4):415‑33.
- Mirande-Ney C, Tcherkez G, Balliau T, Zivy M, Gilard F, Cui J, et al. Metabolic leaf responses to potassium availability in oil palm (Elaeis guineensis Jacq.) trees grown in the field. Environmental and Experimental Botany. juill 2020;175:104062.
- Cui J, Chao De La Barca JM, Lamade E, Tcherkez G. Potassium nutrition in oil palm: The potential of metabolomics as a tool for precision agriculture. Plants People Planet. juill 2021;3(4):350‑4.
- Dubos B, Bonneau X, Flori A. Piloter la fertilisation du palmier à huile [Internet]. éditions Quae; 2020 [cité 22 févr 2024]. Disponible sur: https://www.quae-open.com/produit/154/9782759232628/piloter-la-fertilisation-du-palmier-a-huile
| Keywords | Potassium; Deficiency; Oil palm; Metabolomics |
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