Coffee cultivation is important to the Brazilian agricultural economy. In addition to being one of the most consumed beverages in the world, it is the fifth most exported agricultural commodity in the country (MAPA, 2017). Brazil is the largest producer and exporter of coffee, with 36% of world production, equivalent to 1.98 T ha-1 (CONAB, 2018) and a total area planted with Arabica and Conilon species totaling 2,282,619 hectares (PERUZZOLO, DA CRUZ, RONQUI, 2019).
For greater crop responsiveness in relation to grain and plant quality, generating increased productivity, adequate management is necessary at all stages of production. In this text, we will discuss how fertilizer management can lead to increased coffee productivity.
When we think about productivity in coffee crops, a very important characteristic of its cycle must be taken into consideration: its biennial nature. Due to this characteristic, there is an oscillation in production in consecutive years, where in one year the crop produces a high load and in the following year the production is lower and biotic and abiotic stresses can further harm productivity rates (FIALHO et al., 2010). Many factors must be taken into consideration when managing coffee plants, such as: liming, fertilization, soil conservation, subsoiling, weed management, pest and disease control, planting density and pruning, thus increasing the plants' response capacity, that is, increasing their productive potential. Regarding fertilization, fertilizer use needs to be done with discretion, especially regarding the time of application (season), fractionation (number of applications), location of application (where to apply) and method of application (fertilizer distribution) (CHAVES, 2002). Remembering that soil analysis must be up to date for management to be successful, avoiding spending on unnecessary applications and quantities.
Chemical fertilization provides immediate crop productivity; however, successive fertilizer applications are necessary for management, due to the rapid depletion of nutrients available to plants. These fertilizers cause excessive costs, soil wear and tear, and limitations on crop production potential (RABELO, 2015). Furthermore, over time, depending on the dose applied, they can cause soil acidification, especially in the case of nitrogen (FRANCIOLI et al., 2016; REZENDE, 2022). In recent years, the use of fertilizers with slow or controlled release technology has increased significantly, such as organomineral and polymerized fertilizers, which are highly efficient compared to conventional fertilizers in coffee cultivation (SILVA, 2017).
Organomineral fertilizers, in addition to providing organic matter, are a way of reusing organic waste from various sectors of agribusiness (DE ALMEIDA & DE ALMEIDA, 2018). The organic matter provided by organomineral fertilizers helps soil quality, improving physical, physicochemical, chemical and biological properties, as the set of these attributes is fundamental for fertility (SOUZA et al., 2018).
NUTRITIONAL DIAGNOSIS OF THE CROP
In order for fertilization management to be carried out in a way that meets the nutritional needs of the crop, the diagnosis of its nutritional status becomes important. The interpretation of nutrient levels organized into fertility classes is insufficient for the assessment of their availability and level of sufficiency, because it does not consider differences in production systems, nutritional demand, genotype cycle and nutrient losses in the system, being generally recommended and should be adjusted with the aid of foliar analysis (GUARÇONI et al., 2019).
For leaf sampling (Table 1), the area must be divided into homogeneous plots, that is, subareas with the same slope (hilltop, mid-slope, lowland, etc.), the same noticeable soil characteristics (color, texture, drainage condition, etc.), the same management (use of correctives, fertilizers, etc.) and with plants of the same variety and age. In addition, the collection must be carried out in a zigzag pattern, aiming to represent the entire area of the homogeneous plot (GUARÇONI et al., 2019).
Table 1 – Sampled part and number of leaves per homogeneous plot for Arabica and Conilon coffees.
Source: Martinez, Carvalho and Souza (1999), adapted: Guarçoni et al. (2019).
The time of foliar sampling may vary according to the purpose of the nutritional assessment to be performed. It is important that the method by which the nutritional status of the plants will be assessed contains standards or reference values for the same sampling period. This is very important, as the standards or reference values change according to the phenological phase of the plant in which the foliar sampling is performed. Leaf samples should be avoided immediately after the application of fertilizers via soil or foliar application, as well as any pesticides. Approximately 30 days should be waited before sampling (GUARÇONI et al., 2019).
For Mesquita et al. (2016), the recommendation for macronutrient fertilization (nitrogen, phosphorus and potassium), and the calculation of the quantity to be applied is made based on soil analysis, production estimate and leaf analysis mainly for nitrogen application. The coffee plant, as a perennial plant with a biennial production cycle, also has different needs from one year to another.
If the expected productivity is less than half of that obtained in the previous year (high), the productivity range is determined, for the purpose of calculating fertilization, as being the average between the two. This procedure aims to avoid accentuating bienniality. If this is not the case, that is, if there was no production (crop in formation or pruned in the previous year), or if the expected production is 50% higher than that obtained, consider, for calculation purposes, the productivity as being that actually expected (MESQUITA et al., 2016).
Nutritional requirements of macronutrients
Phosphorus in coffee plants acts on the root system, the formation of the plant's wood and is also very important in the setting of fruits. Regarding phosphate fertilization, it is observed that the lack of this nutrient causes immediate disturbances in the metabolism and development of plants (LAWLOR; CORNIC, 2002). Furthermore, it should not be based exclusively on the production of grains in formation, since fertilizer applications should also aim at the growth of new branches and internodes for the future harvest (GUERRA et al., 2006).
Official fertilization recommendations for coffee plants (GUIMARÃES et al., 1999; RAIJ et al., 1997) suggest that the P requirement in adult coffee plants is low, mainly due to the low export of this element by the beans and that the maximum recommended doses of P2THE5 are around 100 kg.ha-1, considering the expected productivity and the amount of P available in the soil. Coffee trees normally produce on new branches, therefore, they need energy to grow and form new reproductive buds to produce adequately every year (VILELA, 2014).
Potassium requirements increase with age and, mainly, with fruiting, with K translocated from the leaves to the fruits due to the high mobility of the nutrient (GUIMARÃES; MENDES, 1997). The application of 250 – 450 kg/ha of potassium is recommended, with lower doses being used when potassium levels in the soil are high and higher doses when this element is in low or medium concentration in the soil. K absorption is similar to that of N, with greater emphasis in rainy seasons, when higher K levels are found in the leaves and, during drier seasons, lower leaf levels due to lower absorption and extraction of K by the fruits (VILELA, 2014). The leaf content considered adequate is 1.9 to 2.4 g kg-1 and the ideal P/K ratio to prevent imbalance is 16 to 18 (MALAVOLTA, 1993).
For coffee plants, potassium is the second most required nutrient and the third most accumulated in the plant, corresponding to 20% of the total macronutrients allocated in the various organs of the plant (PREZOTTI and LANI, 2013). According to these authors, the requirement of conilon coffee for K increases with the age of the plant, being essentially greater when it reaches the production phase. Its supplementation in deficient soils provides an improvement in crop yield (NASCIMENTO and LAPIDO-LOUREIRO, 2009). Potassium directly influences the productivity and quality of coffee beans by acting on enzymatic activity, synthesis and transport of carbohydrates, thus providing greater beverage quality for well-nourished plants (FRANÇA NETO, 2016). According to Clemente (2010), the absence of K can cause metabolic disorders affecting both plant development and the production and physical and chemical characterization of coffee beans. There is an increase in the percentage of shriveled fruits and a decrease in the size of the grains, resulting in a reduction in productivity and compromising the quality of the beverage (MANCUSO, 2012).
Nitrogen is the nutrient required in the greatest quantity by coffee crops (MALAVOLTA et al., 1993), as a result of its functions as a constituent of protein molecules, enzymes, coenzymes, nucleic acids and cytochromes, among others. When nitrogen fertilizer is applied, part of it is recovered by the root system and aerial part, part remains in the soil while another portion may be immobilized in the litter, which is the layer that is above the soil and is formed by remains of leaves, branches, fruits and other plant parts or may be lost from the soil-plant system (VILELA, 2014).
According to official recommendations, for coffee plants in production, N doses are based on expected production and the nutrient content in the leaf. Doses ranging up to 450 kg ha are recommended.-1 of N per agricultural year, supplied during the rainy season, from September to March, including the flowering, fruiting and vegetative development phases (RAIJ; CANTARELLA; QUAGGIO, 1997; RENA; MAESTRI, 1987; RIBEIRO; GUIMARÃES; ALVARES, 1999).
Another point to note is that, as there are losses of some nutrients mainly through volatilization (N) and leaching (N and K), it is recommended that the fertilizer be applied to the soil in installments, for better utilization. Thus, for these two macroelements, it is usual to divide the recommended amount into 3 or 4 applications, during the rainy season (MESQUITA et al., 2016).
Table 2 shows the fertilization recommendations for coffee crops from the third year of cultivation, the period in which grain production effectively begins.
Table 2. For N, the dose will be defined based on the expected production and leaf analysis. For P and K, what defines it is the soil analysis and the expected production.
Source: Aegro, 2023.
Sulfur
For Paiva (2008), sulfur is important in the nutrition and production of coffee plants, since sulfur in plants forms substances that determine the quality of the product, playing important roles, especially in the metabolism of albumins and in enzymatic reactions. Sulfur predominates in the plant in organic form, mainly in proteins, since all plant proteins contain the element. The SO remains as SO4 -2 in the tissue is relatively low. As it is a nutrient that is not very mobile in the plant, deficiency symptoms occur in the youngest leaves, which in turn turn yellow (citrine yellow) due to the lack of chlorophyll in the chloroplasts, as the nutrient is a component of proteins and participates in the synthesis of chlorophyll. The shortening of the internodes and the defoliation of the plant may also occur (GUIMARAES; MENDES, 1997). In addition, they present brittle, woody stems with stunted growth, reduced flower set, and the fruits are discolored, slightly greenish, with late yellowing (NOGUEIRA, 2001). The sulfur requirement aiming for a productivity of 40 bags per hectare is 12 kg/ha.
Nutritional requirements of micronutrients
The main micronutrients required by the coffee plant are B, Cu, Fe, Mn and Zn, which, although required in small quantities, are of great importance for the growth, development and production of the coffee plant (MIGUEL et al., 2002). The micronutrients B, Zn and Cu are considered the most important for the growth and production of the coffee plant, and are also the most studied (MARTINEZ et al., 2014).
Boron is a micronutrient that contributes to flower fertilization, as it acts in cell division. Therefore, its scarcity directly affects the productivity of Brazilian coffee plants. Boron absorption occurs through mass flow, with periods of water deficit presenting lower levels. Fertilization via soil and foliar application are alternatives for supplementing this nutrient in coffee crops (BORGES et al., 2017).
Under B deficiency, phenol accumulation occurs, which is related to the role of boron in the formation of cis-diol complexes with certain sugars and phenols. Under these conditions, the substrate flow is shifted to the pentose phosphate cycle, thus increasing phenol biosynthesis (MARTINEZ et al., 2014). In response to phenol accumulation, polyphenol oxidase activity increases in B-deficient tissues (LEWIS, 1980; LOOMIS & DURST, 1991; MARSCHNER, 2012), which, together with excess phenols, causes destruction of the cell membrane and, consequently, death of plant tissue (MARSCHNER, 2012).
Copper benefits plants through its effect as a micronutrient, fungistatic and tonic. This micronutrient is essential for plants because it is a component of many enzymes and proteins and is involved in numerous metabolic pathways (MARTINEZ et al., 2014). Several enzymes that contain or are activated by Cu catalyze oxidation-reduction reactions (MARSCHNER, 2012). In addition, Cu can exert direct or indirect effects on fungi. As a direct effect, the influence of this micronutrient is related to its fungistatic capacity, denaturing pathogen proteins (MARTINEZ et al., 2014). The nutritional requirement for boron by coffee plants is 200–500 g/ha/year, and the recommended application is 3 kg/ha/year.
As for Zn, low levels of this element in coffee plants can affect reproductive development more than vegetative development (FAVARO, 1992). Zn deficiency can cause a decrease in seed production (MALAVOLTA et al., 1997; MENGEL & KIRKBY, 1987), which may be related to the reduced development of anthers and the inviability of pollen grains when the plant is deficient in this element (SHARMA et al., 1987; SHARMA et al., 1990).
Neves et al. (2011) observed that the supply of Zn positively influenced the production and quality of coffee beans, characterized by their size, percentage of bored beans, electrical conductivity and potassium leached from the beans. The results of Martinez et al. (2013) corroborated the previous ones and also indicated that the beans of coffee plants supplied with Zn presented higher levels of chlorogenic acids and greater antioxidant activity. The nutritional requirement of zinc by the coffee plant is 200–500 g/ha/year and the application of 6 kg/ha/year is recommended.
The supply of micronutrients to the coffee plant, whether via soil or leaves (GUIMARÃES et al., 1999; RENA & FAVARO, 2000), should begin before the rapid expansion stage of the fruit. If micronutrients are applied via soil, it should be done after flowering, since micronutrient sources generally have a low release rate.
If the micronutrients are supplied via the leaves (Table 3), this can be done around 30 days after anthesis, since absorption via the leaves and the distribution of micronutrients in the plants are faster processes (RENA & FAVARO, 2000).
Table 3. The nutritional status of the plant in coffee crops is indicated by leaf analysis of the 3rd or 4th pair of fully expanded leaves.
Source: Aegro, 2023.
ILSA solutions for coffee fertilization management
ILSA Brasil has a complete portfolio of organic and organomineral fertilizers that meet all the nutritional requirements of the coffee plant (Figure 1).
Figure. ILSA fertilization plan for coffee crops. Source: ILSA BRASIL
As discussed in the text, organic and organomineral fertilizers allow plants to make greater use of nutrients, help increase organic matter in the soil and promote balanced vegetative growth, which provides greater productivity and expression of genetic potential.
FERTIL is an organic fertilizer obtained from the AZOGEL matrix rich in organic nitrogen, which will be gradually made available, organic carbon and amino acids. The presence of carbon in the fertilizer enhances the activity of soil microorganisms, which use carbon as an energy source for their metabolic processes. The application of FERTIL is indicated at the beginning of a new sprouting, in order to standardize the sprouting of the branches and in the post-harvest period, where the nutrients and amino acids present in the fertilizer will be stored by the plants during the dormant period. With the application of FERTIL, the leaves remain green for longer, which increases the photosynthetic rate and consequently the accumulation of reserves by the plants.
GRADUAL MIX is a line of organomineral fertilizers that combines the AZOGEL matrix with mineral nutrient raw materials. The GADUAL MIX line provides the macronutrients nitrogen, phosphorus and potassium more efficiently due to the complexation of these nutrients by the amino acids contained in the AZOGEL matrix, where losses due to volatilization and leaching are lower. In addition, the presence of the AZOGEL matrix in the fertilizer promotes increased biological activity of the soil, increased CTC around the fertilizer and balanced vegetative growth due to the presence of organic nitrogen.
ILSAMIN POTENTE is a fluid organic fertilizer for soil application (via drench at the base of the plant) obtained from the GELAMIN matrix rich in organic nitrogen, amino acids and organic carbon combined with humic substances that promote greater activation of the plant root system and enhance the absorption of water and nutrients.
ILSAMIN BORO is an organomineral fertilizer that combines the GELAMIN matrix with the nutrient boron, which, as discussed in the text, is one of the micronutrients most required by coffee crops. The GELAMIN matrix promotes the complexation of boron, which provides a faster absorption of this element by the plant. ILSAMIN BORO is indicated during the flowering period and has the ability to increase flower fertilization and consequently promote gains in productivity.
ETIXAMIN KALLY is an organomineral fertilizer obtained by combining the GELAMIN matrix with nutrients S and K, two essential nutrients to promote greater filling and uniformity of grain maturation. The presence of the GELAMIN matrix promotes greater absorption speed of these nutrients and greater efficiency in the translocation process of photoassimilates.
Bibliographic references
AEGRO BLOG. Available https://blog.aegro.com.br/adubacao-para-cafe/, consulted July 2023.
BORGES, RP et al. Boron sources via soil and foliar fertilization in coffee plants. 2017.
CARMO, Davi Lopes do et al. Micronutrients in soil and coffee leaves under agroforestry system in southern Minas Gerais. Revista Ceres, Viçosa, v. 61, Suplemento, p. 838-848, 2012.
CHAVES, Júlio César Dias. Soil management: fertilization and liming, before and after the establishment of coffee plantations. Agronomic Institute of Paraná, 2002.
CLEMENTE, JM. Nitrogen and potassium nutrition affecting growth, production, chemical composition and beverage quality of Coffea arabica L.. Dissertation (Master's) – Universidade Federal de Viçosa, Postgraduate Program in Phytopathology, Viçosa, MG, 2010.
CONAB: National Supply Company. Monitoring of the Brazilian coffee harvest – 2018 Harvest. Brasília, Brazil. 2018.
DE ALMEIDA, AMANDA APARECIDA DE; DE ALMEIDA, FERNANDA FERRANTE. Production of organomineral fertilizer from organic waste. University of Uberaba- UNIUBE 2018.
FAVARO, Jose Romeu Aith. Growth and production of Coffea arabica L. in response to zinc foliar nutrition in the presence of potassium chloride. 1992.
FRANCIOLI, Davide et al. Mineral vs. organic amendments: microbial community structure, activity and abundance of agriculturally relevant microbes are driven by long-term fertilization strategies. Frontiers in microbiology, vol. 7, p. 1446, 2016.
FIALHO, CMT et al. Weed competition with coffee crops in two infestation seasons. Planta Daninha, Viçosa (MG), v. 28, p. 969-978, 2010.
FRANÇA NETO, AC Fertigation of conilon coffee (Coffea canephora) in the Zona da Mata region of Rondônia. Thesis (Doctorate) – São Paulo State University, Faculty of Agricultural Sciences. 2016. 101 p.
GUARÇONI M, A. et al. Fertilization and liming recommendations. 2019.
GUERRA, AF et al. Coffee irrigation management, with controlled water stress, for flowering uniformity. Good agricultural practices in coffee production. Viçosa, p. 83-115, 2006.
GUIMARÃES, RJ; MENDES, ANG Mineral nutrition of coffee plants. Lavras, UFLA/FAEPE, 70p, 1997.
GUIMARÃES, PTG et al. Recommendations for the use of soil amendments and fertilizers in Minas Gerais, 5th Approximation. Soil Fertility Commission of the State of Minas Gerais, Viçosa, BRA, 1999.
LAWLOR, D. Wꎬ; CORNIC, G. Photosynthetic carbon assimilation and associated metabolism in relation to water deficits in higher plants. Plant, cell & environment, v. 25, no. 2, p. 275-294, 2002.
LEWIS, DH Boron, lignification and the origin of vascular plants‐a unified hypothesis. New Phytologist, vol. 84, no. 2, p. 209-229, 1980.
LOOMIS, W.D.; DURST, Robert W. Boron and cell walls. In: Current topics in plant biochemistry and physiology: Proceedings of the… Plant Biochemistry and Physiology Symposium held at the University of Missouri, Columbia (USA). 1991.
MALAVOLTA, E. Mineral nutrition and fertilization of coffee plants: maximum economic harvests. São Paulo: Agronômica Ceres, 43 p. 1993.
MALAVOLTA, E. et al. Be the doctor of your coffee plantation. Piracicaba: Informações Agronômicas, 1993. Insert.
MALAVOLTA, Euripides; VITTI, Godofredo César; OLIVEIRA, Sebastião Alberto de. Assessment of the nutritional status of plants: principles and applications. 1997.
MANCUSO, MAC Sources and doses of potassium in coffee crops (Coffea arabica L.). Dissertation (Master in Agronomy (Agriculture)) – Faculty of Agronomic Sciences, São Paulo State University “Júlio de Mesquita Filho”. 2012. 71f
MARSCHNER P. Marschner's mineral nutrition of higher plants. 3rd ed. New York, Academic Press. 651p, 2012.
MARTINEZ, Herminia Emilia Prieto et al. Zinc supplementation, production and quality of coffee beans. Ceres Magazine, v. 60, p. 293-299, 2013.
MARTINEZ, Herminia Emilia Prieto et al. Mineral nutrition of coffee plants and beverage quality. Ceres Journal, v. 61, p. 838-848, 2014.
MENGEL, K.; KIRKBY, EA Principles of plant nutrition. Bern. International Potash Institute, p. 687-695, 1987.
MESQUITA, Carlos Magno de et al. Coffee manual: management of coffee plantations in production. Belo Horizonte: Emater-MG, p. 1-52, 2016.
MIGUEL, AE et al. Micronutrient contents in soil samples analyzed by the MAPA laboratory in Varginha, Southern Minas Gerais. In: BRAZILIAN CONGRESS OF COFFEE RESEARCH, 28th, 2002, Caxambu. Rio de Janeiro: MAPA/PROCAFÉ, p. 76-77. 2002.
NASCIMENTO, M.; LOUREIRO, FEL Potassium in Brazilian agriculture: alternative sources and routes. Fertilizers: agroindustry and sustainability. Rio de Janeiro, CETEM, p. 305-335, 2009.
NEVES YP et al. Effect of zinc and its form of supply on production and quality of coffee beans. Journal of the Science of Food and Agriculture, 91:2431-2436. 2011.
NOGUEIRA, F ,D.; SILVA, EB; GUIMARÃES, PTG Potassium Fertilization of Coffee Plants: potassium sulfate. Washington: SOPID, 2001. 81p.
PAIVA, BRUNO DE OLIVEIRA. PHOSPHORUS AND SULFUR CONTENT IN COFFEE RECEIVED IN DIFFERENT DOSES AND P SOURCES2THE5. 2008.
PERUZZOLO, Marina Carvalho; DA CRUZ, Bruna Costa Ferreira; RONQUI, Ludimilla. Pollination and coffee productivity in Brazil. Pubvet, v. 13, p. 152, 2019.
PREZOTTI, LC; LANI, JA Nutrition of Conilon Coffee. In: FERRÃO, RG; FONSECA, AFA; FERRÃO, MAG; VERDIN FILHO, AC; V.; VOLPI, PS; DE MUNER, LH; LANI, JA; PREZOTTI, LC; VENTURA, JA; MARTINS, DS; MAURI, AL; MARQUES, EMG; ZUCATELI, F. Conilon coffee: production techniques with improved varieties. 4th ed. Vitória, ES: Incaper, Chap 11, p. 296 – 327, 2012.
RABELO, KCC Organomineral and mineral fertilizers: phytotechnical aspects in industrial tomato cultivation. 2015. 70 p. Dissertation (Master's in Agronomy) - Federal University of Goiás, Goiânia, 2015.
RAIJ, B. van et al. Fertilization and liming recommendations for the State of São Paulo. 2nd ed. Campinas: Agronomic Institute/FUNDAG (Technical Bulletin, 100). 285 p. 1997.
RAIJ, B. van; CANTARELLA, H.; QUAGGIO, JA Stimulants. Raij, B. Van; Cantarella, H.; Quaggio, JA, p. 97-101, 1997.
RENA, AB; FÁVARO, JRA Nutrition of the coffee plant via leaves. Coffee: Productivity, quality and sustainability. Viçosa, MG, Federal University of Viçosa, p. 149-208, 2000.
RENA, AB; MAESTRI, M. Ecophysiology of the coffee plant. Ecophysiology of the coffee plant. Piracicaba: Brazilian Association for Potash and Phosphate Research, p. 119-147, 1987.
REZENDE, Camila Isabel Pereira. Multispectral images to discriminate fertilizer sources in coffee plants. 2022.
RIBEIRO, AC; GUIMARÃES, PTG; ALVARES, VHV Recommendations for the use of correctives and fertilizers in Minas Gerais: 5th approach. Viçosa, MG: UFV, 359 p. 1999.
SHARMA PN, et al. Zinc deficiency and earlier development in maize. Plant and Cell Physiology, 28:11-18. 1987.
SHARMA PN, et al. Zinc deficiency and pollen fertility in maize (Zea mays). Plant and Soil, 124:221-225. 1990.
SILVA, ECC Influence of organomineral and slow-release fertilizer sources on coffee quality. 2017. 25 p. TCC (Graduation) – Agronomy Course, Cerrado Patrocínio University Center, Patrocínio, 2017.
SOUZA, Lucas Andrade et al. Qualitative and quantitative analysis of soil aggregates under plastic film associated with organomineral fertilization in a coffee area. Scientia agraria, v. 19, n. 2, p. 142-153, 2018.
VILELA, Diego Júnior Martins. Initial growth of coffee cultivars with different doses of nitrogen, phosphorus and potassium. 2014.
Authors
- Agr Eng. Dr. Angélica Schmitz Heinzen
- Agricultural Eng. Msc. Carolina Custodio Pinto
- Agricultural Eng. Msc. Thiago Stella de Freitas
