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Nutrient dynamic in cocoa leaves under different nitrogen sources: a reference tool for foliar analysis

Dinâmica nutricional em folhas de cacau sob diferentes fontes de nitrogênio: um instrumento de referência para a análise foliar

Abstract

Cocoa is a crop in increasing demand and cultivated worldwide. However, basic information concerning the movement of nutrients in leaves over time is still unknown, and methods to find an optimal time to collect a sample are still ambigu-ous. The present work focused on describing the movement of foliar nutrients (N, P, K, Ca and Mg) in productive 5-year-old cocoa clone CCN51 plants at the same dose of 114.8 kg ha-1 under different sources of nitrogen fertilization (Urea, calcium ni-trate, ammonium sulfate and a control without application). Samples were taken from the time the leaf reached 70% of its total expansion until 10 months of age. The results indicated that the contents of N, Ca and Mg increased as the leaf grew, remained stable between 116 and 158 days of shoot emergence (DSE) and then decreased at the beginning of the leaf senescence period. While the K and P con-tents decrease from the beginning of the trial until 158 DSE where they are stable until the final stage of leaf life. Around 110 to 120 DSE, the leaves of cocoa CCN51 show a more stable nutritional content, a period in which samples can be collected for leaf analysis.

Index terms
nitrogen fertilization; nutrient absorption; sampling; cocoa leaves; nutrition

Resumo

O cacau é uma cultura em demanda crescente que é cultivada em todo o mundo. No entanto, informações sobre os mecanismos de transporte de nutrientes nas folhas, em função do tempo, ainda continuam desconhecidas, e os métodos para encontrar um período ótimo para a amostragem permanecem ambíguos. O presente trabalho teve como objetivo descrever o transporte de nutrientes foliares (N, P, K, Ca e Mg) em plantas produtivas de 5 anos de cacau (clone CCN51), na mesma dose de 114,8 kg ha-1, sob diferentes fontes de fertilização nitrogenada (Ureia, Nitrato de Cálcio, Sulfato de Amônio e um controle negativo sem tratamento). A amostragem foi efetuada quando a folha alcançou 70% de sua expansão total até aos 10 meses de idade. Os resultados revelaram que os conteúdos de N, Ca e Mg aumentaram à medida que a folha crescia, mantendo-se estável entre 116 e 158 DSE e di-minuindo no início do período de senescência da folha. Entretanto, os conteúdos de K e P foram diminuindo desde o início do ensaio até 158 DSE, onde se mantiveram estáveis até à fase final da vida da folha. Nos valores entre 110 e 120 DSEs, as folhas de cacau CCN51 mostraram um conteúdo nutricional mais estável, período em que as amostras podem ser recolhidas para análise foliar.

Termos para indexação
fertilização com nitrogênio; absorção de nutrientes; amostragem; folhas de cacau; nutrição

Introduction

Cocoa (Theobroma cacao L.) is a major cash crop in many tropical countries (LÓPEZ et al., 2019 LÓPEZ, M.; CRIOLLO, J.; HERNÁNDEZ, M.; LOZANO, M. Physicochemical and microbiological dynamics of the fermentation of the CCN51 cocoa material in three maturity stages. Revista Brasileira de Fruticultura, Jaboticabal, v.4, n.3, p.1-13, 2019. ). In Ecuador, cocoa is one of the main export products, with a planted area of 601,954 ha, annual production of 283,680 t and a yield of 0.63 tha-1 (MÁRQUEZ; CUICHÁN, 2021 MÁRQUEZ, J.; CUICHÁN, M. Encuesta de superficie y producción agropecuaria continua 2020. 10.ed. INEC, 2021. p.1-55. Disponível em: https://www.n9.cl/xuhm9. Acesso em: 19 febr. 2022.
https://www.n9.cl/xuhm9...
), currently being the first producer in Latin Americaand the fifth in the world ranking of cocoa producing countries, contributing 5% of production (FAOSTAT, 2021 FAOSTAT - Food and Agriculture Organization Corporate Statistical. Crops and livestock products. 2021. Disponível em: https://www.bit.ly/3wsxjCw. Acesso em: 19 dec. 2021.
https:/www./bit.ly/3wsxjCw...
; HERRERA et al., 2022).

Nutrients are necessary for the plant in dif-ferent quantities, so their deficit or excess can affect the physiological functioning of the plant. Nutrients are generally taken from the soil, but also by the leaves and other or-gans (SORIA, 2008 SORIA, N. Nutrición foliar y defensa natural. In: CONGRESO ECUATORIANO DE LA CIENCIA DEL SUELO, 11., 29-31 oct. 2008, Quito. Proceedings […]. 2008. p.1-11. ).

The content of a mineral element in the leaf is a measure of the actual nutrient uptake of the plant, and can show a strong correlation with yields (FOSTER; PRABOWO, 2002 FOSTER, H.L.; PRABOWO, N.E. Overcoming the limitations of foliar diagnosis in oil palm. In: INTERNATIONAL OIL PALM CONFERENCE AND EXHIBITION, 2002, Bali. Proceedings […]. Medan; IOPRI, 2002. p.269– 281. ).

Due to the influence of environmental con-ditions and aging, some nutrient concentra-tions increase while others decrease under similar conditions, depending on their mo-bility in the plant and the effects of dilution; limiting the use of foliaranalysis for diagnos-tic purposes (WALWORTH; SUMNER, 1987 WALWORTH, J.; SUMNER, M. The diagnosis and recommendation integrated system (DRIS). Advances in Soil Science, New York, v.6, p.149-188, 1987. ).Therefore, leaf nutrient content depends on leaf age, new leaf development, fruiting, light intensity and seasonal effects. Stand-ardized sampling techniques foreach crop and experienced personnel are required, since the leaves sampled must be of the same age to derive nutrient standards (VAN VLIET; GILLER, 2017 VAN VLIET, J.A.; GILLER, K.E. Mineral nutrition of cocoa: a review. Advances in Agronomy, Amsterdam, v.141, p.185–270, 2017. ).

In addition, Wessel (1971) WESSEL, M. Fertilizer requirements of cacao (Theobroma cacao L.) in South-Western Nigeria. Amsterdam: Koninklijk Instituut voor de Tropen, 1971. p.1-106. (Communication, 61). suggested stand-ards for determining N and P content of co-coa leaves at different ages and times of the year. The young leaves sampled were the second and third fully green leaves of the last shoot below the apex of the fan-shaped branches; the older leaves were those di-rectly adjacent to these.

N is an essential nutrient for all plants and is a key participant in plant metabolism, and a prime constituent of amino acids, proteins, enzymes, nucleic acids, chlorophylls and hor-mones. For this reason, nitrogen deficiency rapidly inhibits plant growth (TAIZ et al., 2016 TAIZ, L.; ZEIGER, E.; MØLLER, I.M.; MURPHY, A. Fisiologia e desenvolvimento vegetal. 6.ed. Porto Alegre: Artmed, 2016. p.888. ). When N fertilizers are applied to the soil can follow different ways like, rapidly taken by the cacao trees or else leached and/or volatilized (DOGBATSE et al., 2021 DOGBATSE, J.; ARTHUR, A.; AWUDZI, G.; QUAYE, A.; KONLAN, S.; AMANING, A. Effects of organic and inorganic fertilizers on growth and nutrient uptake by young cacao (Theobroma cacao L.). International Journal of Agronomy, London, p.1-10, 2021. ). In addition, the chemical form of N taken up, whether inorganic (such as nitrate) or organic (such as amino acids), may significantly influ-ence plant shoot and root growth, and N use efficiency (FRANKLIN et al., 2017 FRANKLIN, O.; CAMBUI, CA.; GRUFFMAN, L.; PALMROTH, S.; OREN, R.; NÄSHOLM, T. The carbon bonus of organic nitrogen enhances nitrogen use efficiency of plants. Plant, Cell and Environment, Hoboken, v.40, n.1, p.25-35, 2017 ). N ‘drives’ uptake of P, K, S and possibly other nutrients; for this reason, the reliable interpretation of sufficiency levels of these nutrients in the leaf is possible only where N concentrations are non-limiting (MILES, 2010 MILES, N. Challenges and opportunities in leaf nutrient data interpretation. In: ANNUAL CONGRESS OF THE SOUTH AFRICAN SUGAR TECHNOLOGISTS’ ASSOCIATION, 83., 25-27 aug. 2010, Durban. Proceedings […]., 2010. p.205-215. ).

A main problem with using cocoa leaf analy-sis is that cocoa leaf nutrient content de-pends on many factors, like: leaf age, the de-velopment of new leaves, fruit bearing, light intensity, and seasonal effects (VAN VLIET;GILLER, 2017 VAN VLIET, J.A.; GILLER, K.E. Mineral nutrition of cocoa: a review. Advances in Agronomy, Amsterdam, v.141, p.185–270, 2017. ). Consequently, knowledge about the movement and evolution of nutri-ents content during leaf development using different N sources is essential to understand processes and changes at the physiological level on the nutritional status of source tis-sues to improve fertilizer use, management and cocoa production. The aim of this study was to evaluate the nutritional dynamics at the leaf level of cocoa (Theobroma cacao L.)clone CCN 51 under the effect of different nitrogen sources in fertilization.

Material and Methods

The study was carried out in Piuntza sector, Zamora Chinchipe province in the southeast of Ecuador, at a latitude of 3º52`27.89`` S and a longitude of 78º53`8.87`` W. One of the main cocoa-producing areas and considered the possible center of origin of cocoa world-wide (MOTAMAYOR et al., 2002 MOTAMAYOR, J.C.; RISTERUCCI, A.M.; LOPEZ, P.A., ORTIZ, C.F.; MORENO, A.; LANAUD, C. Cacao domestication. I: the origin of the cacao cultivated by the Mayas. Heredity, Glasgow, v.89, p.380-386, 2002. ). The cli-matic classification of the study site is Af (equatorial or humid tropical climate) ac-cording to Köppen-Geiger (RUBEL; KOTTEK, 2010 RUBEL, F.; KOTTEK, M. Observed and projected climate shifts 1901-2100 depicted by world maps of the Köppen-Geiger climate classification. Meteorologische Zeistschrift, Stuttgart, v.19, p.135-141, 2010. ), at an altitude of 849 meters above sea level, with an average temperature of 22.4 ºC and annual rainfall of 1918 mm. The experi-ments were carried out in a 5-year-old cocoa crop, clone CCN51 in production.Forty trees were selected, homogenized in age, number of main branches, plant height,phenological stage and canopy cover. A completely ran-domized design (CRD) was used, with 4 treatments and 10 replications, with the fol-lowing treatments: T1 Control without Nitro-gen, T2: Urea as Ammoniacal source, T3: Cal-cium nitrate as Nitric source and T4: Ammo-nium sulfate as Ammoniacal source.

To avoid limitations or masking of the effect of the N sources, an initial soil analysis was performed (Table 1), in which fertility was evaluated and a base fertilization of the ele-ments P, K, Ca, and B was applied, with the exception of N and S (no sulfur deficiency), prior to the application of treatments. In ad-dition, 1 kg plant-1 of lime in the form of Ca (OH)2 was applied to raise the pH to 6.99 and promote the dynamic equilibrium of the ele-ments in the soil. For treatments, using co-coa nutrient extraction information (FURCAL-BERIGUETE, 2017 FURCAL-BERIGUETE, P .Extracción de nutrientes por los frutos de cacao en dos localidades en Costa Rica. Agronomía Mesoamericana, San José, v.28, n.1, p.113-129, 2017. ) and soil nutri-ents based on soil analysis (Table 1), a dose of 114.8 kg ha-1 of N was established, divided monthly during nine months (November 2018 to August 2019).

Table 1
Soil chemical parameters prior to base fertilization and treatment application.

During nine months, leaf samples were taken at 60, 88, 116, 158, 199, and 275 days after shoot emergence for nutrient content analy-sis. For this purpose, 10 or 15 leaves per rep-etition were labeled and collected from non-productive shoots of the last season, from the middle third of the canopy following a stand-ard protocol for foliar analysis as suggested by De Mello and Rozane (2020). The minerals analyzed were: N, P, K, Ca, and Mg, where N was analyzed by the Kjeldahl method, P by colorimetry, and the elements K, Ca, and Mg by atomic absorption were carried out ac-cording to the methodology of the Associa-tion of Official Analytical Chemistry – AC (2016). Analyses carried out at the soil and water management laboratory of the INIAP Santa Catalina Experimental Station.

Results and Discussion

Leaf nutritional dynamics (Figure 1) shows an increase in N content (x̄=2.19%) at 116 days of shoot emergence (DSE) that then gradu-ally decreases until the end of the observa-tion as mentioned by , in Santana and Igue (1979) SANTANA, M.; IGUE, K. Composição química das folhas do cacaueiro em função da idade e da época do ano. Revista Theobroma, Brasilia, v.9, n.2, p.63-76, 1979. mature leaves total N levels de-crease during new shoot development. Sig-nificant statistical differences and higher N contents are presented: at 88 DSE with the control and at 116 DSE with the application of N treatments. The curves of the ammo-nium sulfate and urea treatments showed stable concentrations during the evaluation period, while the curves with calcium nitrate and control showed greater variations.

Figure 1
Macronutrients at leaf level in cocoa CCN51 under application of different N sources. A) Nitrogen; B) Phosphorus; C) Potassium; D) Calcium, and E) Magnesium. Error bars are ± S.E.

Leaf nitrogen content between 88 to 199 DSE present values higher than 2 % that are considered a normal concentration in cocoa leaves according to Van Vliet and Giller (2017) VAN VLIET, J.A.; GILLER, K.E. Mineral nutrition of cocoa: a review. Advances in Agronomy, Amsterdam, v.141, p.185–270, 2017. , an indicating an increase of N as leaf grew and photoassimilate production increased.

N is a structural element of chlorophyll, where 75% of leaf N is directed to the chlo-roplast, consequently affecting leaf green-ness and chlorophyll accumulation (Yama-shita et al., 2020 YAMASHITA, H.; SONOBE, R.; HIRONO, Y.; MORITA, A.; IKKA, T. Dissection of hyperspectral reflectance to estimate nitrogen and chlorophyll contents in tea leaves based on machine learning algorithms. Scientific Reports, London, v.10, p.1-11, 2020. ). So, during leaf growth the process of cell division and expansion is con-tinuous, requiring an accumulation of N in the chloroplasts, resulting in a constant in-crease in leaf N content until the leaf stops growing and the senescence stage begins.

It is important to remember that, when an adequate supply of N is provided, vigorous vegetative growth and intense green color are observed; conversely, excessive amounts can prolong the growing season and delay maturity (TISDALE; NELSON, 1970 TISDALE, S.; NELSON, W. Fertilidad de los suelos y fertilizantes. Barcelona: Montaner and Simon Editorial, 1970. p.760. ).

Then, if inadequate soil N supply, N from the leaves is mobilized to younger plant organs (BALTA et al., 2015 BALTA, R.; RODRÍGUEZ, A.; GUERRERO, R.; CACHIQUE, D.; ALVA, E.; ARÉVALO, L.; LOLI, O. Absorción y concentración de nitrógeno, fósforo y potasio en Sacha Inchi (Plukenetia volubilis L.) en suelos ácidos, San Martín, Perú. Folia Amazónica, Iquitos, v.24. n.2, p.123–130, 2015. ). In the case of rice, N deficiency hinders the syn-thesis of chlorophyll and proteins, thus re-ducing photosynthesis andaffecting dry matter production (WANG et al., 2020 WANG, Y.; SHI, P.; JI, R.; MIN, J.; SHI, W.; WANG, D. Development of a model using the nitrogen nutrition index to estimate in-season rice nitrogen requirement. Field Crops Research, Amsterdam, v.245, p.1-10, 2020. ).

When analyzing the concentration of P and K, a decrease was observed as the leaves aged. This is probably due to the fact that the developing fruits serve as sinks for K and P, which mobilize these nutrients from the leaves (KANT; KAFKAFI, 2002 KANT, S.; KAFKAFI, U. Absorción de potasio por los cultivos en distintos estadios fisiológicos. Rehovot: The Hebrew University of Jerusalem, Faculty of Agricultural, Food and Environmental Quality Sciences, 2002. v.3 p.263-280. Disponível em: https://www.ipipotash.org/udocs/SesionV.pdf.
https://www.ipipotash.org/udocs/SesionV....
). Significant statistical differences were detected at 88 DSE and a higher P content with the use of ammonium sulfate. Meanwhile, the presence of urea at 116 DSE and the absence of N sources (control) at 275 DSE revealed higher K concentrations (Figure 1). The values re-ported by Hosseini et al. (2017) HOSSEINI, S.; TRUEMAN, S.; NEVENIMO, T.; HANNET, G.; BAPIWA, P.; POIENOU, M.; WALLACE, H. Effects of shade-tree species and spacing on soil and leaf nutrient concentrations in cocoa plantations at 8 years after establishment. Agriculture, Ecosystems and Environment, Amsterdam, v.246, n.1, p.134–143, 2017. for foliar P concentrations range from 0.10 to 0.15 %, similar to those found from 116 to 275 DSE.

In the case of K concentrations reported by Hosseini et al. (2017) HOSSEINI, S.; TRUEMAN, S.; NEVENIMO, T.; HANNET, G.; BAPIWA, P.; POIENOU, M.; WALLACE, H. Effects of shade-tree species and spacing on soil and leaf nutrient concentrations in cocoa plantations at 8 years after establishment. Agriculture, Ecosystems and Environment, Amsterdam, v.246, n.1, p.134–143, 2017. between 1.64 and 1.96 %, are higher than those presented in the present investigation.

P is a major component of nucleic acids, phospholipid membranes and phosphory-lated compounds, 22-26% of total leaf P is required for membranes and other cellular structures, suggesting a basic P cost for leaf "infrastructure". Another percentage of leaf P is used in metabolism, where it is rapidly cycled (CROUS; ELLSWORTH, 2020 CROUS, K.; ELLSWORTH, D. Probing the inner sanctum of leaf phosphorus: measuring the fractions of leaf P. Plant and Soil, New York, v.454, p.77–85, 2020. ). There-fore, as it is easily cycled the amount of P re-maining in the leaf is low, as shown by leaf analysis, in addition to the decrease in P con-tent as the leaf grows.

Low P content severely limits leaf growth, due to reduction of compounds such as adenosine triphosphate (ATP) that photosynthetic limita-tions for carbohydrate production (TIMLIN et al., 2017 TIMLIN, D.J.; NAIDU, T.C.M.; FLEISHER, D.H.; REDDY, V.R. Quantitative effects of phosphorus on maize canopy photosynthesis and biomass. Crop Science, Madison, v.56. n.6, p.3156-3169, 2017. ).

K is important in plant metabolism because it favors the synthesis of lipids, carbohyrates and proteins; it also regulates sto-matal aperture, reduces water loss and opti-mizes plant photosynthesis processes (MELO et al., 2021 MELO, E. de; SOUTO, A.G.; FERREIRA, L.; MOREIRA, B.L.; LUCENA, I.H.; MONTEIRO, R.; SILVA, R.M.; ANDRADE, C.J.; FERNANDES, P.A. Leaf mineral composition and noni fruit production under vegetal mulching and potassium fertilization. Scientia Horticulturae, Amsterdam, v.281, p: 1-11, 2021. ). K is necessary for assimilatde translocation from leaves to fruits and other sinks (PATRICK et al., 2001 PATRICK, J.W.; ZHANG, W.; TYERMAN, S.D.; OFFLER, C.E.; WALKER, N.A. Role of membrane transport in phloem translocation of assimilates and water. Functional Plant Biology, Chippendale, v.28, p.697-709, 2001. ). As the leaf grows its photosynthetic activity decreases, therefore the amount of K required to transport photoassimilates will be less, re-flecting a low foliar K content. Due to K is required for sucrose loading in the phloem (ARIAS et al., 2018 ARIAS, L.M.; GUTIÉRREZ-BOEM, F.H.; SALVAGIOTTI, F. Contrasting effects of phosphorus and potassium deficiencies on leaf area development in maize. Crop Science, Washington, v.58, n.5, p.2099-2109, 2018. ). A minimum concentra-tion of tissue K is therefore essential to support metabolic processes, and uptake and transport mechanisms, and to maintain cellular turgidity (SINGH; REDDY, 2017 SINGH, K.; REDDY, R. Potassium starvation limits soybean growth More than the Photosynthetic processes across CO2 levels. Frontiers in Plant Science, Lausanne, v.8, p.1-16, 2017. ).

In the case of Ca and Mg, their concentrations increased until 158 DSE, and then began to decrease until the end of the obser-vation (Figure 2). Significant statistical differ-ences were observed at 88 DSE when the presence of urea revealed the lowest Ca concentrations and at 199 DSE the absence of N sources (control) showed a higher Ca con-tent. In the case of Mg, the presence of urea at 60 DSE and the control at 275 DSE reveals an increase in its content (Figure 1).

Figure 2
General movement of elements at the leaf level in CCN51 cocoa in days after shoot emergence. Dashed line indicates the ideal initial time to take samples for leaf analysis, approximately at the fourth month after shoot emergence. Error bars are ± S.E.

Ca exhibits a dual function, both as a struc-tural component of cell walls and mem-branes and as intracellular second messen-ger. Thus, Ca concentration in the cytosol is found low level and increased to generate a signal when the plant required (THOR, 2019 THOR, K. Calcium-nutrient and messenger. Frontiers in Plant Science, Lausanne, v.10, p.440, 2019. ).

This indicates that when the leaf arrives at the senescence stage, the leaf Ca content will be higher than at the beginning of leaf growth, due to its accumulation in the cell walls and a small portion in the cytosol.

The calcium content in the leaf increased with leaf growth from 116 to 199 DSE, show-ing values higher than those reported by Hosseini et al. (2017) HOSSEINI, S.; TRUEMAN, S.; NEVENIMO, T.; HANNET, G.; BAPIWA, P.; POIENOU, M.; WALLACE, H. Effects of shade-tree species and spacing on soil and leaf nutrient concentrations in cocoa plantations at 8 years after establishment. Agriculture, Ecosystems and Environment, Amsterdam, v.246, n.1, p.134–143, 2017. between 1.70 and 1.43 %, and then the content decreased to 1.10 % until the end of the observation.

During the light-dependent reactions and the Calvin-cycle stages of photosynthesis, Mg is involved in three key biochemical pro-cesses: 1) in the light-dependent reaction, the chlorophyll molecule is composed of a central Mg ion surrounded by a group of at-oms, 2) Mg can also promote the synthesis of adenosine triphosphate (ATP), 3) Mg is a cofactor and allosteric modulator for en-zymes, and regulates the Calvin cycle by ac-tivating many enzymes (WANG et al., 2018 WANG, J.; WEN, X.; ZHANG, X.; LI, S.; ZHANG, D. Co-regulation of photosynthetic capacity by nitrogen, phosphorus and magnesium in a subtropical Karst Forest in China. Scientific Reports, London, v.8, p.1-9, 2018. ).

So, when the leaf begins to grow and in-crease its photosynthetic activity, the leaf Mg content increases as it is required in the pho-tosynthetic process; when the senescence stage begins, the content of this element de-creases.

In addition, the Mg content from 116 to 199 DSE was greater than 0.60 %; this these val-ues are higher than those reported by Hosseini et al. (2017) HOSSEINI, S.; TRUEMAN, S.; NEVENIMO, T.; HANNET, G.; BAPIWA, P.; POIENOU, M.; WALLACE, H. Effects of shade-tree species and spacing on soil and leaf nutrient concentrations in cocoa plantations at 8 years after establishment. Agriculture, Ecosystems and Environment, Amsterdam, v.246, n.1, p.134–143, 2017. where the concentrations were between 0.57 and 0.37 %.

It is important to take into account that the nutritional demand of the leaves changes during their life cycle, having a close relationship with the rhythm and characteristics of vegetative growth and the phenological state. Because the longevity of the leaves is determined by the physiological state of the plants at the time of production (VINICIO, 2002 VINICIO, F. Mecanismos de absorción de nutrimentos por el follaje. In: MELÉNDEZ, G; MOLINA, E. (ed.). Memoria fertilización foliar: principios y aplicaciones. San Jose: University of Costa Rica, 2002. p.1-6. ). Not only the demand for nutrients determines the movement of elements in the plant, but also the absorption capacity of the plant.

The movement of nutrients at leaf level ex-pressed as a percentage of dry weight is equal to the mobility reported by Van Vliet and Giller (2017) VAN VLIET, J.A.; GILLER, K.E. Mineral nutrition of cocoa: a review. Advances in Agronomy, Amsterdam, v.141, p.185–270, 2017. , where N and Ca increase with age, while P and K are more or less con-stant with decreasingconcentration. Such movement may be due to retranslocation of nutrients to other sink organs as they are re-quired, as well as the age of the leaf due to the fact that during leaf senescence there is a synthesis of proteolytic enzymes that hy-drolyze nutrients, inducing the retransloca-tion of breakdown products, to storage tis-sues (RALHAN; SINGH, 1987 RALHAN, P.; SINGH, S. Dynamics of nutrients and leaf mass in central Himalayan forest trees and shrubs. Ecology, Washington, v.68, n.6, p.1974-1983, 1987. ; COVELO; GALLARDO, 2002 COVELO, F.; GALLARDO, A. Effect of pine harvesting on leaf nutrient dynamics in young oak trees at NW Spain. Forest Ecology and Management, Amsterdam, v.163, n.1/3, p.161-172, 2002. ). In the case of P it is po-tentially more subtle to analyses chemically than N, as it is commonly maintained at a concentration of about an order of magni-tude lower in plants compared to leaf N (CROUS; ELLSWORTH, 2020 CROUS, K.; ELLSWORTH, D. Probing the inner sanctum of leaf phosphorus: measuring the fractions of leaf P. Plant and Soil, New York, v.454, p.77–85, 2020. ).

It is important to remember that as men-tioned by Wessel (1971) WESSEL, M. Fertilizer requirements of cacao (Theobroma cacao L.) in South-Western Nigeria. Amsterdam: Koninklijk Instituut voor de Tropen, 1971. p.1-106. (Communication, 61). , foliar analysis is mainly a useful tool to detect and identify pronounced nutrient deficiencies; it is diffi-cult to use foliar analysis to establish a quan-titative fertilizer recommendation without considering soil analysis.

Conclusions

Results indicate that leaf nutrient movement of N, P, K, Ca and Mg, did not show major dif-ferences when subjected to different sources of nitrogen nutrition or in the absence of fer-tilization over time, indicating that the plant regulates its own internal processes of nutri-ent uptake and mobilization in the leaf.

There is a great variation in nutritional con-tent over time depending mainly on the age of the leaf regardless of the N fertilization supplied, so collecting samples for foliar anal-ysis too early or too late may result in misin-terpretations of results.

In this situation, it is possible to determine a period in which elements N, P, K, Ca and Mg, depending on their age, are more stable in their contents being an ideal moment to take a sample for foliar analysis, which is located around the fourth month after the sprout emission.

Acknowledgments

We would like to thank Augusto Carrión for his openness to carrying out the study on his farm. The present study was supported by Project 09-DI-FARNR-2021 (Universidad Nacional de Loja) competitive grant.

  • ARIAS, L.M.; GUTIÉRREZ-BOEM, F.H.; SALVAGIOTTI, F. Contrasting effects of phosphorus and potassium deficiencies on leaf area development in maize. Crop Science, Washington, v.58, n.5, p.2099-2109, 2018.
  • AOAC - Association Of Official Analytical Chemist. Official methods of analysis of the association of official chemistry. 20.ed. Gaithersburg, 2016. p.700.
  • BALTA, R.; RODRÍGUEZ, A.; GUERRERO, R.; CACHIQUE, D.; ALVA, E.; ARÉVALO, L.; LOLI, O. Absorción y concentración de nitrógeno, fósforo y potasio en Sacha Inchi (Plukenetia volubilis L.) en suelos ácidos, San Martín, Perú. Folia Amazónica, Iquitos, v.24. n.2, p.123–130, 2015.
  • COVELO, F.; GALLARDO, A. Effect of pine harvesting on leaf nutrient dynamics in young oak trees at NW Spain. Forest Ecology and Management, Amsterdam, v.163, n.1/3, p.161-172, 2002.
  • CROUS, K.; ELLSWORTH, D. Probing the inner sanctum of leaf phosphorus: measuring the fractions of leaf P. Plant and Soil, New York, v.454, p.77–85, 2020.
  • DOGBATSE, J.; ARTHUR, A.; AWUDZI, G.; QUAYE, A.; KONLAN, S.; AMANING, A. Effects of organic and inorganic fertilizers on growth and nutrient uptake by young cacao (Theobroma cacao L.). International Journal of Agronomy, London, p.1-10, 2021.
  • FAOSTAT - Food and Agriculture Organization Corporate Statistical. Crops and livestock products. 2021. Disponível em: https://www.bit.ly/3wsxjCw. Acesso em: 19 dec. 2021.
    » https:/www./bit.ly/3wsxjCw
  • FOSTER, H.L.; PRABOWO, N.E. Overcoming the limitations of foliar diagnosis in oil palm. In: INTERNATIONAL OIL PALM CONFERENCE AND EXHIBITION, 2002, Bali. Proceedings […]. Medan; IOPRI, 2002. p.269– 281.
  • FRANKLIN, O.; CAMBUI, CA.; GRUFFMAN, L.; PALMROTH, S.; OREN, R.; NÄSHOLM, T. The carbon bonus of organic nitrogen enhances nitrogen use efficiency of plants. Plant, Cell and Environment, Hoboken, v.40, n.1, p.25-35, 2017
  • FURCAL-BERIGUETE, P .Extracción de nutrientes por los frutos de cacao en dos localidades en Costa Rica. Agronomía Mesoamericana, San José, v.28, n.1, p.113-129, 2017.
  • HOSSEINI, S.; TRUEMAN, S.; NEVENIMO, T.; HANNET, G.; BAPIWA, P.; POIENOU, M.; WALLACE, H. Effects of shade-tree species and spacing on soil and leaf nutrient concentrations in cocoa plantations at 8 years after establishment. Agriculture, Ecosystems and Environment, Amsterdam, v.246, n.1, p.134–143, 2017.
  • KANT, S.; KAFKAFI, U. Absorción de potasio por los cultivos en distintos estadios fisiológicos. Rehovot: The Hebrew University of Jerusalem, Faculty of Agricultural, Food and Environmental Quality Sciences, 2002. v.3 p.263-280. Disponível em: https://www.ipipotash.org/udocs/SesionV.pdf.
    » https://www.ipipotash.org/udocs/SesionV.pdf.
  • LÓPEZ, M.; CRIOLLO, J.; HERNÁNDEZ, M.; LOZANO, M. Physicochemical and microbiological dynamics of the fermentation of the CCN51 cocoa material in three maturity stages. Revista Brasileira de Fruticultura, Jaboticabal, v.4, n.3, p.1-13, 2019.
  • MÁRQUEZ, J.; CUICHÁN, M. Encuesta de superficie y producción agropecuaria continua 2020. 10.ed. INEC, 2021. p.1-55. Disponível em: https://www.n9.cl/xuhm9 Acesso em: 19 febr. 2022.
    » https://www.n9.cl/xuhm9
  • MELLO, R. de; ROZANE, D. Leaf analysis as diagnosis tool for balanced fertilization in tropical fruits. In: SRIVASTAVA, A.K.; CHENGXIAO, H. Fruit crops: diagnosis and management of nutrient constraints. Amsterdam: Elsevier, 2020. p.131-143.
  • MELO, E. de; SOUTO, A.G.; FERREIRA, L.; MOREIRA, B.L.; LUCENA, I.H.; MONTEIRO, R.; SILVA, R.M.; ANDRADE, C.J.; FERNANDES, P.A. Leaf mineral composition and noni fruit production under vegetal mulching and potassium fertilization. Scientia Horticulturae, Amsterdam, v.281, p: 1-11, 2021.
  • MILES, N. Challenges and opportunities in leaf nutrient data interpretation. In: ANNUAL CONGRESS OF THE SOUTH AFRICAN SUGAR TECHNOLOGISTS’ ASSOCIATION, 83., 25-27 aug. 2010, Durban. Proceedings […]., 2010. p.205-215.
  • MOTAMAYOR, J.C.; RISTERUCCI, A.M.; LOPEZ, P.A., ORTIZ, C.F.; MORENO, A.; LANAUD, C. Cacao domestication. I: the origin of the cacao cultivated by the Mayas. Heredity, Glasgow, v.89, p.380-386, 2002.
  • PATRICK, J.W.; ZHANG, W.; TYERMAN, S.D.; OFFLER, C.E.; WALKER, N.A. Role of membrane transport in phloem translocation of assimilates and water. Functional Plant Biology, Chippendale, v.28, p.697-709, 2001.
  • RALHAN, P.; SINGH, S. Dynamics of nutrients and leaf mass in central Himalayan forest trees and shrubs. Ecology, Washington, v.68, n.6, p.1974-1983, 1987.
  • RUBEL, F.; KOTTEK, M. Observed and projected climate shifts 1901-2100 depicted by world maps of the Köppen-Geiger climate classification. Meteorologische Zeistschrift, Stuttgart, v.19, p.135-141, 2010.
  • SANTANA, M.; IGUE, K. Composição química das folhas do cacaueiro em função da idade e da época do ano. Revista Theobroma, Brasilia, v.9, n.2, p.63-76, 1979.
  • SINGH, K.; REDDY, R. Potassium starvation limits soybean growth More than the Photosynthetic processes across CO2 levels. Frontiers in Plant Science, Lausanne, v.8, p.1-16, 2017.
  • SORIA, N. Nutrición foliar y defensa natural. In: CONGRESO ECUATORIANO DE LA CIENCIA DEL SUELO, 11., 29-31 oct. 2008, Quito. Proceedings […]. 2008. p.1-11.
  • TAIZ, L.; ZEIGER, E.; MØLLER, I.M.; MURPHY, A. Fisiologia e desenvolvimento vegetal. 6.ed. Porto Alegre: Artmed, 2016. p.888.
  • THOR, K. Calcium-nutrient and messenger. Frontiers in Plant Science, Lausanne, v.10, p.440, 2019.
  • TIMLIN, D.J.; NAIDU, T.C.M.; FLEISHER, D.H.; REDDY, V.R. Quantitative effects of phosphorus on maize canopy photosynthesis and biomass. Crop Science, Madison, v.56. n.6, p.3156-3169, 2017.
  • TISDALE, S.; NELSON, W. Fertilidad de los suelos y fertilizantes. Barcelona: Montaner and Simon Editorial, 1970. p.760.
  • VAN VLIET, J.A.; GILLER, K.E. Mineral nutrition of cocoa: a review. Advances in Agronomy, Amsterdam, v.141, p.185–270, 2017.
  • VINICIO, F. Mecanismos de absorción de nutrimentos por el follaje. In: MELÉNDEZ, G; MOLINA, E. (ed.). Memoria fertilización foliar: principios y aplicaciones. San Jose: University of Costa Rica, 2002. p.1-6.
  • WALWORTH, J.; SUMNER, M. The diagnosis and recommendation integrated system (DRIS). Advances in Soil Science, New York, v.6, p.149-188, 1987.
  • WANG, J.; WEN, X.; ZHANG, X.; LI, S.; ZHANG, D. Co-regulation of photosynthetic capacity by nitrogen, phosphorus and magnesium in a subtropical Karst Forest in China. Scientific Reports, London, v.8, p.1-9, 2018.
  • WANG, Y.; SHI, P.; JI, R.; MIN, J.; SHI, W.; WANG, D. Development of a model using the nitrogen nutrition index to estimate in-season rice nitrogen requirement. Field Crops Research, Amsterdam, v.245, p.1-10, 2020.
  • WESSEL, M. Fertilizer requirements of cacao (Theobroma cacao L.) in South-Western Nigeria. Amsterdam: Koninklijk Instituut voor de Tropen, 1971. p.1-106. (Communication, 61).
  • YAMASHITA, H.; SONOBE, R.; HIRONO, Y.; MORITA, A.; IKKA, T. Dissection of hyperspectral reflectance to estimate nitrogen and chlorophyll contents in tea leaves based on machine learning algorithms. Scientific Reports, London, v.10, p.1-11, 2020.

Publication Dates

  • Publication in this collection
    07 Nov 2022
  • Date of issue
    2022

History

  • Received
    18 Feb 2022
  • Accepted
    15 July 2022
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