The wheat (Triticum spp.) is an annual plant that belongs to the Poaceae family. Three species of the genus Triticum, T. aestivum L., T. monococcum L. and T. durum L., are cultivated, the first being the species of greatest economic importance. Wheat grain is processed into flour, which can be consumed in the form of bread, pasta, cakes and cookies (STEMPKOWSKI et al., 2022). When it does not reach the quality standard for human consumption, the grain can be used in the manufacture of animal feed. The plant can be used for grazing and production of silage for animals (BRAMMER et al. 2011; CUNHA et al. 2011; FONTANELI et al. 2011).
Wheat is among the most cultivated and produced cereals in the world, occupying the third position, behind only corn (Zea mays L.) and rice (Oryza spp.) (STEMPKOWSKI et al., 2022). Wheat cultivation is an important practice in the composition of sustainable agricultural production systems, being an important option for crop rotation and succession in grain production systems (DE MORI 2016). National production is around 5.4 million tons of grains in an area slightly larger than 2 million hectares, with an average yield of approximately 2,700 kg/ha–¹. The Southern Region is responsible for almost 90% of national production, with emphasis on the states of Paraná and Rio Grande do Sul, the main Brazilian producers (CONAB 2021). Brazil is not self-sufficient in wheat production, with less than 50% of domestic consumption being produced in the country, generating the need to import the cereal (CONAB 2021). National wheat production has the potential to supply the quantity necessary for supply, however, factors such as high production costs, adequacy of quality to end use, meteorological fluctuations, weaknesses in relationships and coordination in the agro-industrial complex, and aspects of international policy affect the competitiveness of Brazilian wheat (DE MORI 2015).
Sowing season
Wheat-growing regions are classified into four (Figure 1) as described by Stempkowski et al., 2022. Region 1 has a cool and wet winter (wheat growing season). Region 2, moderately warm and humid, has slightly higher average temperatures than region 1, but both have a good distribution of rainfall throughout the wheat crop cycle. In region 2, wheat is sown earlier than in region 1. The agricultural landscape of these two regions is similar and, after the summer harvest, consists mainly of soybeans (Glycine max (L.) Merr.) and corn, oats are sown first (Oatmeal spp.) and then wheat. In the state of Paraná (the northernmost of the three states in the Southern Region), off-season corn is usually grown, competing for area with winter wheat. However, the further south you go, the greater the risk of frost, reducing the area of off-season corn. Thus, the largest winter area is occupied by black oats (Avena strigosa Schreb.) is sown in the fall and around 20% of the arable land is cultivated with wheat (varying in the microregions). Region 3, hot and moderately dry, is a transition area between the subtropical climate of the south of the country and the tropical climate of most of Central Brazil. In this region, wheat is sown in late summer and fall (March-April). Second-crop corn and wheat compete for area during the winter. In central Brazil (region 4), in the Cerrado (the Brazilian equivalent of the African savannas), wheat is grown under a warm and dry winter. The climate has a smaller annual temperature variation compared to the south of the country. However, it is characterized by well-defined rainy seasons. In the fall and winter (April-September), rainfall is scarce. Crops in this region, depending on the sowing season, require irrigation. Thus, there are two cultivation systems: dryland cultivation when wheat is sown in February-March; or irrigated cultivation carried out from April onwards.
Figure 1. Wheat-growing regions and wheat production in Brazilian regions. Adapted from Embrapa by Stempkowski et al., 2022.
Disease management
For Lau et al., 2020, disease management first requires accurate diagnosis. Diagnosis can be visual, based on symptoms. Some fungal diseases may have similar symptoms and require laboratory analysis with the installation of humid chambers (to favor sporulation of the pathogen) or isolation in culture medium. Control methods for a given disease should be initiated even before planting the crop. Measures such as crop rotation and the use of healthy seeds aim to eliminate or reduce the initial inoculum. For some difficult-to-treat diseases, the only effective measure may be the selection of cultivars resistant to the pathogen (LAU et al., 2020).
Monitoring crops by direct inspection of plants, using traps and sensors, is essential to track the rate of progress and apply chemicals at the exact moment when the action thresholds (AT) recommended by historical studies are reached. This is the way to obtain the best ratio between control costs and grain yield protection (LAU et al., 2020).
Fertilization management
Wheat plants naturally prefer deep soils, good fertility, medium to heavy texture, water retention capacity, but well drained and pH around 5-5.5 without aluminum and manganese saturation. The availability of nutrients for the plant is decisive in production, with nitrogen being a limiting factor for crop development due to its importance in the formation of amino acids, proteins, chlorophyll and essential enzymes that stimulate plant growth and development (FUERTES-MENDIZABAL et al., 2010).
Soil acidity correction is carried out through liming. This aims to reduce the soil acidity index through the application of limestone, composed of the neutralizing agents calcium carbonate (CaCO3) and magnesium (MgCO3).
Fertilization recommendations for nitrogen (N) vary according to the soil organic matter content, with doses of up to 60 to 80 kg of N/ha. Apply 15 to 20 kg of N/ha at sowing and the remainder as topdressing between the tillering and stalk elongation stages (a period that includes approximately 30 to 45 days after emergence). For higher doses of N, it is recommended to divide nitrogen fertilization into two topdressing applications, the first application at the beginning of tillering; and the second, at the beginning of elongation. The application of N after earing or booting generally does not affect grain yield, but it can increase the protein content of this part of the plant. In general, this increase in protein does not necessarily imply that the gluten strength (W) value is altered to the point of modifying the commercial classification of wheat (DE QUÍMICA, 2016).
Nitrogen topdressing in dual-purpose wheat should be carried out immediately after the first cut or grazing by animals, whose phenological stage coincides with the period close to the beginning of stem elongation (approximately 42 to 70 days after crop emergence), in plants with a height greater than 20 cm. The subsequent cut or grazing can be carried out 28 to 35 days after the first (DE QUÍMICA, 2016).
The application of P and K to the soil is based on the concept of productivity. These nutrients should be applied at the time of sowing, using a formula containing NPK, and placed 2.5 cm next to and below the seed, in order to form a soil barrier between the seed and the fertilizer (DE BONA; DE MORI; WIETHÖLTER, 2016). The values of nutrient extraction and export (Table 1) by the wheat crop are also important parameters to be considered in the nutritional management of the crop. The nutritional needs of a crop are determined by the total amounts of nutrients absorbed and accumulated in the different parts of the plant. The amounts extracted vary according to the production and the factors that alter it, such as variety, soil fertility, climatic conditions, etc. The amounts exported, which are the amounts that leave the property through production, depend on the destination of this production (VASCONCELLOS, et al., 2000).
Table 1. Nutrient extraction and export values by wheat crops, obtained by different authors.
Source: Adapted, Martins (2019).
K is the second element that is in the highest concentration in the vegetative tissue and in the wheat grains. This justifies the high demand for K by the wheat crop and, consequently, the care that must be taken with the management of potassium fertilization. In addition to acting in osmoregulation (control of salt concentrations in the tissues or cells) and in the resistance of the wheat plant to drought, K also acts in important functions, such as grain filling and final product quality (BARKER; PILBEAM, 2015). For De Bona; De Mori; Wiethölter, 2016, in wheat plants, K deficiency is initially expressed in the older leaves, which become yellowish in the apex region and then present necrosis or drying of the apical region of the leaf in an inverted “V” shape. Thus, when the doses are very high (> 100 kg/ha-1 of K2O), it is recommended to apply part of the K before sowing or as top dressing in the initial stages of crop growth and development.
The use of organomineral fertilizers can be recommended for wheat crops. However, the quality of the organomineral fertilizer, represented by the type and origin of the material used, stability, homogeneity and concentration of nutrients must be criteria to be considered. Normally, the recommendation should take into account the macronutrient in the highest concentration in the organomineral fertilizer to be used.
How can ILSA products help produce a high-yield crop?
ILSA has a complete line of solid, liquid and water-soluble fertilizers obtained from the AZOGEL and GELAMIN matrices that provide nutrients, enhance the biological activity of the soil and contribute to increasing the productivity of wheat crops.
ILSA FERTILIZATION RECOMMENDATION FOR WHEAT CROPS
THE AZOGEL presents a gradual release of nitrogen and allows adequate nutrition throughout the production cycle of plants, reducing losses due to volatilization and leaching generally present in other nitrogen fertilizers. In this way, it is possible to reduce the number of applications and increase agricultural productivity while respecting the environment. Therefore, AZOGEL ensures balanced plant nutrition, in accordance with the nutritional requirements of crops in their various phenological phases.
The value of an organic fertilizer goes beyond the simple supply of nutrients, as its use provides many beneficial effects to the soil. Organic matter acts as an energy source for beneficial microorganisms (which fix nitrogen from the air in the rhizosphere and fungi that associate with the roots), improves structure and aeration, and has the ability to store moisture. It has a regulating effect on soil temperature, slows down the fixation of phosphorus and increases the cation exchange capacity (CEC), and helps to hold potassium, calcium, magnesium, and other nutrients in forms available to the roots, protecting them from leaching by rainwater or irrigation practices.
Furthermore, due to the thermal hydrolysis process to obtain the matrix AZOGEL ILSA products are free of possible pathogens that could be incorporated into the soil using common organic fertilizers, also helping to control diseases. Regarding the ILSA products recommended for the management of wheat crop fertilization, the Gradual Mix and Azoslow products are obtained from the AZOGEL matrix.
The line GRADUAL MIX® characterized by the presence of high levels of organic nitrogen and amino acids from hydrolyzed proteins associated with other sources of mineral fertilizers. It is a line of organomineral fertilizers for planting, that is, supplying NPK, but the great benefit of this line is that the mineral raw materials are combined with the AZOGEL matrix that promotes better use of mineral elements. Phosphorus (P), like the nutrients nitrogen (N), potassium (K), calcium (Ca), sulfur (S) and magnesium (Mg), is classified as a macronutrient for plants. The P content in plants is always lower than that of N and K, and although soils contain large amounts of total P, its availability to plants is very low due to the tendency to form compounds with very low solubility in the soil (BERTONCELLO, 2010). K is a macronutrient present in plants in quantities similar to N. It has high mobility in the plant, both between cells and between tissues and between different parts of the plant, via xylem and phloem. K is commonly redistributed from old leaves to new leaves. It is the most abundant cation in the cytoplasm, also occurring in high concentration in the chloroplast (BERTONCELLO, 2010). Although it is not part of the chemical structure of plant compounds, it performs very important regulatory functions, being necessary to activate at least 50 enzymes. The need for potassium for protein synthesis in higher plants is currently well known. It is also linked to the photosynthetic process at various levels, participates in ATP synthesis, and affects the rate of CO assimilation.2 and maintaining the turgor of guard cells, which control the opening and closing of stomata to regulate the rate of plant transpiration and the diffusion of CO2 atmospheric (ANGHINONI & BISSANI, 2004).
THE AZOSLOW® belongs to the ILSA FERT line and is a nitrogen coverage option that combines the AZOGEL matrix with mineral raw materials (urea) and that increases the use of N when compared to urea, for example, which has a high potential for losses. Nitrogen (N) is the element that presents the greatest difficulties in management in agricultural production, due to its high solubility, even in technically oriented properties. Due to its condition as a constituent of proteins, N deficiency affects all vital processes of the plant, photosynthetic capacity decreases, growth is delayed and reproduction is impaired (CAMARGO & SÁ, 2004). The application of N to the soil, in wheat cultivation, is certainly one of the safest crop management practices in relation to economic return, as research has shown that the efficiency of N use varies depending on the dose applied, and its value ranges between 12 (RAMOS, 1981) and 21 (WIETHöLTER et al., 2007) kg of grains per kg of N added.
Already the GELAMIN is obtained from the enzymatic hydrolysis of collagen. From the matrix GELAMIN ILSA produces liquid and water-soluble fertilizers for foliar application and/or fertigation. Containing 16 amino acids in their composition that are essential for plant development, these compounds participate in the activation and stimulation of primary (photosynthesis) and secondary (stress) metabolism of plants. For wheat crops, ILSA's indications for foliar applications, derived from the matrix GELAMIN are: ILSAMIN Potente, ILSAMIN Ágile and ETIXAMIN Kally.
For ILSAMIN Potente®, the time to apply this product is in the planting furrow. The product combines the GELAMIN matrix with humic substances, which enhances the plant's rooting process. In addition, it promotes the complexation of Fe and Al oxides and the consequent release of P into the system, increasing the CEC (cation exchange capacity) and the complexation of chemical elements.
ILSAMIN ÁGILE® can be used at any time during the cycle. Its composition contains more than 95% of GELAMIN matrix, which makes it highly concentrated in amino acids and can be placed in the crop during periods of climatic stress or at times during the cycle when the plant's energy demand is higher. The application of amino acids results in greater productivity, as they act on the physiological processes of plants, stimulating the formation of proteins and derivatives and also reducing the freezing point of the cell, which protects the plant against the effects of low temperatures (TAIZ et al., 2013).
ETIXAMIN KALLY® is an end-of-cycle product, that is, it enhances the grain filling process. It is an organomineral fertilizer that contains nitrogen, potassium and sulfur. Satisfactory levels of sulfur (S) in the soil are important for the success of wheat crops because the adequate availability of this nutrient increases the efficiency of N use (protein synthesis), the elasticity necessary for the development and formation of a bread dough with good capacity to withstand fermentation (carbon dioxide retention) and kneading, and are therefore determinants of the rheological quality of gluten, and have a direct relationship with the quality of baking (SGARBIERI, 1996). Both gliadin and glutenin have their biosynthesis dependent on S because they are composed of amino acids, such as cystine, cysteine and methionine, and have inter and intramolecular disulfide bonds, in addition to free sulfhydryl groups, in the composition of the gluten network (WIESER, 2007). Thus, wheat plants deficient in S produce flour with low technological quality for baking purposes (DE BONA; DE MORI; WIETHÖLTER, 2016). The application of kally aims to complement the supply of these nutrients by the soil and is carried out via foliar application. Its nutritional elements are 100% available to plants and allow a rapid response of crops.
Soil chemical analysis is the main tool for diagnosing and monitoring the degree of P and K availability in the soil, as well as for deciding whether to apply fertilizers containing these nutrients to wheat crops. Similar to N fertilization, the supply of P and K is based on the concept of variable productivity, so that the amount to be applied is proportional to the expected yield of the wheat crop (DE BONA; DE MORI; WIETHÖLTER, 2016).
Bibliographic references
ANGHINONI, I.; BISSANI, CA Phosphorus and phosphate fertilizers. Soil fertility and crop fertilization management, v. 1, p. 117-137, 2004.
BARKER, Allen V.; PILBEAM, David J. (Ed.). Handbook of plant nutrition. CRC press, 2015.
BERTONCELLO, Mirela Rossetto. Evaluation of the physiological quality of wheat seeds produced in soil with different levels of phosphorus. 2010. Master's Dissertation. Federal University of Pelotas.
BRAMMER, Sandra Patussi et al. Biotechnology applied to wheat cultivation. 2011.
CAMARGO, FAO; SÁ, ELS Nitrogen and nitrogen fertilizers. Soil fertility and crop fertilization management. Porto Alegre: Genesis, p. 93-116, 2004.
CONAB (2021). Conab – Historical Series of Harvests. https://www.conab.gov.br/info-agro/safras/serie-historica-das-safras. Accessed 26 Aug 2021.
CUNHA GR DA, PIRES JLF, VARGAS L. Basis for competitive and sustainable wheat production in Brazil. In: Pires JLF, Vargas L, Cunha GR da (Eds.) Wheat in Brazil: bases for competitive and sustainable production. Passo Fundo, Embrapa Trigo. pp. 19-26, 2011.
DE BONA, FD; DE MORI, C.; WIETHÖLTER, S. Nutritional management of wheat crops. 2016. Available at: http://www.ipni.net/publication/ia-brasil.nsf/0/47520FE3CAA3AEF183257FE70048CC16/$FILE/Page1-16-154.pdf
CHEMISTRY, CQFS-Commission; SOIL, Fertility. Liming and fertilization manual for the states of Rio Grande do Sul and Santa Catarina. Viçosa, Brazilian Society of Soil Science. 376p, 2016.
DE MORI, C. Economic aspects of production and use. 2015.
FONTANELI, Renato Serena et al. Dual purpose wheat. 2011.
FUERTES-MENDIZÁBAL, T. et al. Improving wheat breadmaking quality by splitting the N fertilizer rate. European journal of agronomy, v. 33, no. 1, p. 52-61, 2010.
LAU, Douglas et al. Major wheat diseases in southern Brazil: diagnosis and management. Passo Fundo, RS, Embrapa Trigo. Online Technical Communication, v. 375, 2020.
MARTINS, G. TABLE OF NUTRIENT EXTRACTION AND EXPORT IN WHEAT CROP. Crop Nutrition, 2019.
RAMOS, M. Characterization of the wheat response curve to nitrogen application. Brazilian Agricultural Research, v. 16, p. 611-615, 1981.
SGARBIERI, VC Proteins in protein foods. São Paulo: Livraria Varela, p. 517, 1996.
STEMPKOWSKI, Lucas Antonio et al. Wheat viruses in Brazil: a historical overview. 2022.
TAIZ et al. Plant physiology and development. Porto Alegre: Artmed, p. 719, 2004.
VASCONCELLOS, CA, et al. Extraction and export of nutrients by forage sorghum crops. In: NATIONAL CONGRESS OF CORN AND SORGHUM, Uberlândia, MG. 23., 2000: ABMS: Embrapa Corn and Sorghum; Uberlândia: Federal University of Uberlândia, 2000.
WIETHÖLTER, S., et al.,2007. Effect of nitrogen application to the soil on grain quality and yield of wheat cultivars. In: BRAZILIAN CONGRESS OF SOIL SCIENCE, 31st, 2007, Gramado. Book of abstracts… Porto Alegre: SBCS, Núcleo Regional Sul, 2007.
WIESER, H. Chemistry of gluten proteins. Food Microbiology, vol. 24, p. 115-119, 2007.
Authors
- Agr Eng. Dr. Angélica Schmitz Heinzen
- Agricultural Eng. Msc. Carolina Custodio Pinto
- Agricultural Eng. Msc. Thiago Stella de Freitas