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Revista Ciencias Técnicas Agropecuarias

On-line version ISSN 2071-0054

Rev Cie Téc Agr vol.30 no.3 San José de las Lajas July.-Sept. 2021  Epub July 01, 2021

 

ORIGINAL ARTICLE

Operation Indicators of the Unit Tractor MF 275-KUHN MC 90S TWIN Forage Corn Harvester

Dr. C. Pedro Antonio Valdés Hernández*  I 
http://orcid.org/0000-0002-8570-0895

MSc. Pascual Daniel Crespo TorresII 
http://orcid.org/0000-0002-9894-9032

MSc. María Victoria Gómez ÁguilaIII 
http://orcid.org/0000-0001-9603-2856

IUniversidad Agraria de La Habana, Facultad de Ciencias Técnicas, San José de las Lajas, Mayabeque, Cuba.

IIUniversidad Politécnica Tecnológica del Estado de Trujillo, Estado Trujillo, Venezuela.

IIIUniversidad Autónoma Chapingo, Departamento de Ingeniería Mecánica Agrícola, Texcoco de Mora, México.

ABSTRACT

The objective of the research carried out was to determine the operating indicators of the unit MF 275 tractor, UHN MC 90S TWIN corn (Zea mayz) forage harvester and the trailer, belonging to “La Ceibana” Farm in Trujillo State. In this work it was obtained that the operating time of the trial corresponds to 82 h and the clean time 17.77 h representing 21.7%, which means a consumption of unproductive time of 78% and a coefficient of use of the time of exploitation of 22%, so there is a reserve for improving the efficiency of the forage corn harvesting process. A productivity per hour of clean time of 5 868.84 kg / h was obtained and a productivity per hour of exploitation time of 1 271.42 kg / h, which is in accordance with the technical characteristics of the machine. Average values are obtained for each control shift, in the case of the mass of 5 487.37 kg, a speed of 3.13 km / h and a fuel consumption of 50.24 L, which yields a value of 12.56 L / h of operation, which is within the working range for this type of agricultural set, with coefficients of variation below of 15.7%, which means a low dispersion of the data obtained and there was a normal distribution of the data obtained.

Keywords: Operation Times; Productivity; Coefficients

INTRODUCTION

Grasses and legumes are the most economical source of animal feed available to a producer to keep his animals healthy, with acceptable levels of productivity and among the varieties par excellence, forage corn (FAO, 2005). Corn production worldwide is greater than any other cereal. Annually, 850,000,000 t of grain are obtained in an area of 162,000,000 ha, with an average production of 5.2 t/ha. The largest producers are the USA and China with 37 and 21% of the total, respectively, with the USA also being the main producer of forage maize with 2.6 million cultivated ha, that is, less than 10% of the area destined for grain maize. followed by Germany and France from the EU. The production of the major grain maize producing countries amounts to: The United States with a production of 365,659,000 t, followed by China (217,000,000 t), Brazil (75,000,000 t), the European Union (68,346,000 t), Ukraine (26,000,000 t), and Argentina (23,000,000 t). The three main exporters are the US, Argentina and Brazil, according to Yara Argentina (2019).

In tropical Latin America, milk was traditionally produced mainly in specialized, dual-purpose systems. The latter has often been viewed as inefficient, of low productivity, and unprofitable system. However, it has persisted over time and substantially increased its importance as a supplier of milk and meat due to its comparative advantages to produce at low cost and generate jobs. The contribution of this system to milk production in the American tropics exceeds 50% (Seré, 1986). In Brazil and Colombia, it is estimated that 35% and 51% of the milk, respectively, come from this system, while, in Venezuela, the contribution is currently calculated to be greater than 90% due to the almost total disappearance of milk. specialized dairy farms (Soto, 2005).

In many farms, a deficient management and use of pastures is observed, in particular with regard to the control of the animal load, over or under grazing, weeding and decreasing in the persistence of the grassland resource with losses in production and economic benefit. It is estimated that no less than 50% of these pastures are in advanced stages of degradation, with a considerable decrease in their potential productivity (Faria, 2006).

The state of Trujillo is located in the western zone of Venezuela and covers 740,000 hectares, of which only 130,000 hectares are used in exploitation with ruminants. In most cases the grazing areas are made up of native grasses of low nutritional quality, they are poorly managed and there is little presence of trees and shrubs in the pastures. This situation, together with other psychosocial and technological factors, has generated a 60% deficit in the milk and meat sectors in the last decade (Torres, 2007).

In most of the ruminant production systems of the state, the use of tree foliage as a source of nutrients for livestock is scarce, and in many cases the biomass of trees and shrubs is occasionally used by animals in grasslands or in secondary forest areas, since most producers only recognize the potential of these species for the delimitation of boundaries and/or as trees that provide shade and wood. Even though there are numerous plant species of wide geographic distribution that are representative of the Zona Trujillana Baja, the nutritional potential and the feasibility of use as forage of most of them for bovines has not been documented in the conditions of the Pie de Monte Andino (Garcia & Medina, 2006).

For this reason, it is necessary to apply new technologies for feeding animals, fundamentally for the dry seasons. It is necessary to create forage areas basically of sugar cane grasses, king grass, corn, pastures and legume species, among others, which generates a high demand of mechanized technologies for the processing of these new food sources in livestock production units.

Harvesting machines and forage mincers adapted to the production conditions of the farm are necessary to harvest and process these crops in the livestock units. These equipment have an important role within the units, since shredding makes the physical breakdown of these plants with high fiber content which facilitates a faster digestion and contributes to a greater contribution of nutrients to the ruminant. That favors higher consumption, so it is necessary to guarantee the quality of the work, with particles smaller than 15-20 mm for fresh consumption and below 5 mm for the manufacture of feed (Delgado, 2005 & Valdés et al., 2012), aspect to take into account for the acquisition of those machines. Therefore, it is necessary to develop mechanized technologies for processing the forage of the different crops, to obtain it in the most appropriate way during for cattle feeding. The determination of the technological and operation indicators of these machines is fundamental for an adequate and more efficient production process (Valdés et al., 2015; De las Cuevas Milán et al., 2015).

On the other hand, investigations have been carried out related to the evaluation of operation parameters of the different agricultural groups, which allow an increase in the organizational efficiency of the technological process of agricultural activities. In Cuba, several authors have carried out studies in this direction, such as Miranda et al. (2002); Morejón et al. (2012) and Miranda et al. (2013), which evaluate the operation indicators of the New Holland L-520, CLAAS DOMINATOR rice harvesters and the means of transport used in the harvest-transport process of rice in the Agroindustrial Complex "Los Palacios", respectively. Similarly, Matos et al. (2010); Matos & García (2012) and De las Cuevas et al. (2014) carry out similar studies, but for the Case-7000 and CAMECO cane harvesters and for the trucks in the transportation of cane, respectively. On the other hand, Ortiz et al. (2011) and Olivet et al. (2012), carry out the technological and operation evaluation for sets of machines in the work of breaking and furrowing for the cultivation of sweet potato, respectively.

The aforementioned studies have been directed to other types of machines within which the forage maize harvesting machine under study is not found, which is used in the processing of forage for the production of animal feed.

Based on these antecedents, the present investigation is developed, whose objective is to determine the operating indicators of the unit MF 275 tractor, KUHN MC 90S TWIN corn (Zea mayz) forage harvester and trailer, for feeding the cattle in the agricultural farm "La Ceibana", Trujillo State, Venezuela.

MATERIALS AND METHODS

Characterization of the Experimental Conditions of the Plot and Group under Study

The research was carried out at “La Ceibana” Farm, in La Ceiba Municipality, Trujillo State, with facilities for feeding and raising cattle. The unit MF 275 tractor and KUHN MC 90S TWIN forage harvester machine was used, with power take-off shaft drive, according to Figure 1. The variety of forage corn was identified for its harvest and transport. The average values of temperature and rainfall of that municipality were obtained, according to INAMEH-Venezuela (2015). The characterization of the natural conditions of the plot was carried out according to the standard NC 34-47: 03 (2003), adapted to the characteristics of the investigation developed.

The harvested area had dimensions of 120 m x 80 m (9,600 m²) and a total of approximately 5 ha for the combine test, with an average of 80 cm between rows and 30 cm between plants, which allowed densities of 6 plants/m² reaching around more than 50,000 plants/ha, of seed maize variety MB 258-CG, from Colombia.

FIGURE 1 Unit consisting of the MF 275 tractor and the KUHN MC 90S TWIN combine harvester. 

La Ceiba Municipality is one of the twenty municipalities that are part of the Trujillo State, in the Andes of Venezuela, its capital is the town of Santa Apolonia. La Ceiba Municipality is located in the lower zone, to the west of the Trujillo State and to the east of Lake Maracaibo. The most important characteristics of the area are referred in Table 1 and in Figure 2 the territorial division can be observed.

TABLE 1 Most important characteristics of Agropecuaria La Ceibana 

Unit evaluation date April-May 2015
Soil type Entisols
Texture Clayey-silty
Relief Plain
Altitude 2 m.a.s.l.
Average annual rainfall 600 to 1000 mm / year
Average annual temperature 30 ºC

Source: INAMEH-Venezuela (2015) & TURITRUJILLO (2015).

Characteristics of the Unit Tractor-Forage Harvester Machine

The fundamental technical characteristics of the MF 275 tractor consist of a power at nominal speed of 62.25 kW and a nominal rotation frequency in the power take-off shaft (PTO) of 540 min-1, used during the evaluation of the performance indicators. Table 2 shows the technical characteristics of the KUHN MC 90S TWIN corn harvester used during the evaluation of the operation indicators.

FIGURE 2 La Ceiba Municipality of Trujillo State-Venezuela. 

TABLE 2 Specifications of the KUHN MC 90S TWIN Forage Harvester 

CHARACTERISTICS KUHN MC 90S TWIN
Number of rows to harvest 2
Height (cm) 325
Width (cm) 295
Mass (kg) 550
Number of mincer blades 10
Number of blades 5
Frequency of rotation at the entrance of the machine / Frequency of rotation of the working element (output) 540/1000
Crushing length (mm) 4 y 6
Row spacing from center to center (cm) of the furrows 68/75/80

Source: Agroterra (2015).

Table 3 shows the technical characteristics of the trailer used.

TABLE 3 Technical characteristics of the trailer 

Tractor power consumption 22,35 kW
Maximum authorized load 15 000 kg
Unloaden Weight (Tare) 4 600 kg
External dimensions 4 600 x 2 400 mm
Interior dimensions 4 590 x 4 300 mm
Side 800 mm
Overlateral 500 mm
Drawer manufactured with F-142 structural steel chassis

Source: Agroterra (2015).

Determination of the Operation Indicators of the Unit

To collect and elaborate the timing data, the standard NC: 34-37: 03 (2003) was used. The duration of each operation was determined by the time difference between the beginning of the operation (end of the previous operation) and the end time of the operation. The difference obtained is noted in the column "time spent", compared to the operation in the column "Designation of operations and interruptions". For the determination of the operation and technological indices, the times of the timing model were classified, as established in NC: 34-37: 03 (2003).

For the determination of the productivity in clean time W1, the harvesting machine was put into operation doing its useful work during its movement through the field, and the amount of harvested mass processed (Q), was measured with a 1 kg precision scale, as seen in Figure 3.

FIGURE 3 Scale used to obtain the amount of mass harvested. 

The time of the beginning and end of the harvesting process of the corn stalks in the field (T1- clean time), as well as the other established times, were done using a precision 1s digital stopwatch.

For the evaluation and determination of the different operation times, productivity and the coefficients, the computer program “Technological Exploitation Evaluation” (TECEXP) designed to determine the technological and exploitation indices of agricultural and forestry machines was used (De las Cuevas et al., 2008).

The evaluation was carried out for an area of 5 ha, where 4 control shifts were carried out, with a minimum of 15 h of clean working time of the unit and the following parameters were also measured:

Length (L) and width of the field, with measuring tapes of 50 m in length and a precision of 5 mm.

Working speed (V) through the expression:

V=L/t, m/s, (1)

Where:

L -

field length, m;

t -

time to travel the length L, s.

RESULTS AND DISCUSSION

Results of the Operation Indicators of the Unit Tractor MF 275, KUHN MC 90S TWIN Forage Harvester and the Trailer

Table 4 shows the results obtained from the technological indicators of operation of the unit during the evaluation carried out in the harvest of the forage corn, in the facilities of La Ceibana Agricultural Farm, Trujillo State, with the use of the "TECEXP" program, according to De las Cuevas et al. (2008).

The total mass of forage harvested amounted to a value of 104.26 t during the entire timing carried out to the unit. A clean time of 17.77 h (21.7%) of a total of 82 hours of operation representing 78.3% of unproductive time. At an average speed of 3.13 km/h, the forward gear of the tractor was located in the fifth reduced speed and the active 4-wheel drive at 2 000 rpm, the investigated set, presented a low operating time utilization coefficient of 22%, characteristic of this type of implement, as a result of the consumption of unproductive time when unloading the material (T22). The rest of the time was used in technological stops (T31), (T33) and (T42) with a total of 11 cases, product of the replacement of belts, oil leaks in the hydraulic system and punctures in the wheels system. The transfer from the workshop to the field and vice versa (T61), where the process was only stopped due to the occurrence of technical failures at the end of the day as a result of the technical expertise.

The technical safety coefficient (K42) was 77%, acceptable since the equipment presents adequate technical conditions for the production process. Similar results obtained González & Lora (2013) when evaluating the operation and economic parameters in forage cutting with different harvesting machines (67%).

A productivity per hour of clean time of 5.87 t/h and an average fuel consumption of 50.54 L/day, approximately 12.56 L/h of operation which is within the working range for this type of set agricultural.

TABLE 4 Operation indicators of the unit consisting of the Massey Ferguson MF 275 tractor, the KUHN MC 90S TWIN combine and the trailer 

No Indices Denomination Unit Index
1 Volume of work done kg 104 260,0
2 Duration of chronometric observation h
Clean time (T1) 17,770
Operating time (T02 = T1 + T2) 65,750
Productive time (T04 = T1 + T2 + T3 + T4) 79,310
Shift time without failures (Tt = T1 + T2 + T3 + T5 + T6 + T7) 75,080
Operating time (T07 = T1 + T2 + T3 + T4 + T5 + T6 + T7) 82,000
3 Hourly productivity: kg/h
Clean time 5 868,84
Operating time 1 585,62
Productive time 1 314,62
Shift time without failures 1 388,67
Of exploitative time 1 271,42
4 8 hour productivity kg/h
In shift time without failures (Wt) 10 593,36
In operation time (W07) 9 741,56
5 Technological safety coefficient (K41) 1,000
6 Technical damage elimination time h 1,73
Number of cases 11
Volume of work done for each failure kg 4 631,14
7 Technical safety factor (K42) 0,77
8 Productive time utilization coefficient (K04) 0,23
9 Coefficient of utilization of the operation time (K07) 0,22

The results obtained from the field test of the operation times, as well as the productivity obtained for each time, are also shown graphically in Figures 4 and 5. The productivity in clean time amounted to 5 868.84 kg/h, which is in accordance with the technical characteristics of the machine.

Table 5 shows the results of the descriptive statistical analysis carried out on the mass of forage harvested in each control shift, the speed and the fuel consumption of the Tractor-Harvester-Trailer set. Average values are seen for each control shift in the case of the mass of 5 487.37 kg, speed 3.13 km/h and a fuel consumption for each working day of 50.24 L, with variation coefficients below 15.7%, which means a low dispersion of the data obtained and a normal distribution of the data obtained was appreciated.

FIGURE 4 Duration of observation of the different operation times. 

FIGURE 5 Productivity per hour of the unit. 

TABLE 5 Statistics of the tractor-harvester-trailer unit 

Indicator) Mass (kg) Speed (km/h) Fuel consumption. (L)
Mean 5487,37 3,13 50,24
Typical deviation 705,14 0,10 4,25
Coefficient of variation 15,7% 3,24% 8,46%

CONCLUSIONS

  • The operating time of the test corresponds to 82 h and the clean time 17.77 h representing 21.7%, which means a consumption of unproductive time of 78% and a coefficient of utilization of the operating time of 22%. Therefore, there is a reserve for improving the efficiency of the forage corn harvesting process.

  • A productivity per hour of clean time of 5,868.84 kg/h and a productivity per hour of operating time of 1,271.42 kg/h was obtained, which is in accordance with the technical characteristics of the machine.

  • Average values ​​are obtained for each control shift, in the case of the mass of 5487.37 kg, a speed of 3.13 km/h and a fuel consumption of 50.24 L, which yields a value of 12, 56 L/h of operation, which is within the working range for this type of agricultural unit, with variation coefficients below 15.7%, which means a low dispersion of the data obtained and a normal distribution of the data obtained.

ACKNOWLEDGMENT

We thank the Cuba-Venezuela agreement and the Universidad Politécnica Territorial del Estado Trujillo, of Venezuela for serving as the headquarters for the teaching of the master's degree in Agricultural Machinery, which made it possible to carry out this research in the area under study.

REFERECES

AGROTERRA: Especificaciones de remolque o tara de pequeño tonelaje, [en línea] 2015, Disponible en: http://www.agroterra.com/ [Consulta: 17 de mayo de 2015]. [ Links ]

DE LAS CUEVAS, M.H.R.; RAVELO, I.; DÍAZ, A.; PANEQUE, R.P.: ¨Evaluación tecnológica y de explotación de la combinada de caña CAMECO¨, Revista Ingeniería Agrícola, ISSN-2306-1545, e-ISSN: 2227-8761, 4(4): 9-15, 2014. [ Links ]

DE LAS CUEVAS, M.H.R.; RODRÍGUEZ, H.T.; HERRERA, P.M.I.; PANEQUE, R.P.: ¨Software para la evaluación tecnológica de las máquinas agrícolas¨, Revista Ciencias Técnicas Agropecuarias, ISSN-1010-2760, e-ISSN: 2071-0054, 17(2): 24-28, 2008. [ Links ]

DE LAS CUEVAS MILÁN, M.H.R.; VALDÉS, H.P.A.; RODRÍGUEZ, A.D.; SUÁREZ, L.R.; DELGADO, R.R.; QUINTANA, V.J.L.: ¨Índices de explotación del tractor BELARUS 510 y la picadora de forraje JF 50¨, Revista Ingeniería Agrícola, ISSN-2306-1545, 5(2): 44-48, 2015. [ Links ]

DELGADO, J.: ¨Experiencias en el uso de forrajes de calidad en un sistema intensivo de producción lechera¨, En: XI Seminario Manejo y Utilización de Pastos y Forrajes en Sistemas de Producción Animal, Barinas, Venezuela, 2005. [ Links ]

FAO: Principales productores de maíz en el mundo, [en línea] 2005, Disponible en: http://www.fao.org [Consulta: 15 de septiembre de 2014]. [ Links ]

FARIA, M.J.: ¨Manejo de pastos y forrajes en la ganadería de doble propósito¨, X Seminario de Pastos y Forrajes. Universidad de Zulia, Venezuela, 1, 2006. [ Links ]

GARCÍA, E.D.; MEDINA, G.M.: ¨Composición química, metabolitos secundarios, valor nutritivo y aceptabilidad relativa de diez árboles forrajeros¨, Zootecnia Tropical, ISSN-0798-7269, 24(3): 233-250, 2006. [ Links ]

GONZÁLEZ, R.R.; LORA, D.: ¨Determinación de parámetros de explotación y económicos en el corte de forraje con diferentes máquinas cosechadoras¨, Revista Ingeniería Agrícola, ISSN-2306-1545, e-ISSN: 2227-8761, 3(2): 31-38, 2013. [ Links ]

INAMEH-VENEZUELA: Climatología del Puerto La Ceiba, [en línea] 2015, Disponible en: http://www.inameh.gob.ve/ [Consulta: 15 de mayo de 2015]. [ Links ]

MATOS, R.N.; GARCÍA, C.E.: ¨Evaluación técnica y de explotación de los camiones en la transportación de la caña¨, Revista Ciencias Técnicas Agropecuarias, ISSN-1010-2760, e-ISSN: 2071-0054, 21(2): 30-33, 2012. [ Links ]

MATOS, R.N.; GARCÍA, C.E.; GONZÁLEZ, G.J.R.: ¨Evaluación técnica y de explotación de las cosechadoras de caña Case-7 000¨, Revista Ciencias Técnicas Agropecuarias, ISSN-1010-2760, e-ISSN: 2071-0054, 19(4): 06-09, 2010. [ Links ]

MIRANDA, C.A.; CASTELLS, H.S.; ÁLVAREZ, A.O.; SANTOS, G.F.; IGLESIAS, C.C.: ¨Análisis de la utilización del tiempo de turno por las cosechadoras arroz CLAAS DOMINATOR¨, Revista Ciencias Técnicas Agropecuarias, ISSN-1010-2760, e-ISSN: 2071-0054, 22(4): 27-31, 2013. [ Links ]

MIRANDA, C.A.M.; IGLESIAS, C.C.; ANILLO, J.; FALCÓN, L.; FIGUEROA, R.R.; RIVERO, R.M.; LARA, R.M.; BECERA, C.A.: ¨Evaluación tecnológica y explotación de las cosechadoras de arroz New Holland L-520¨, Revista Ciencias Técnicas Agropecuarias, ISSN-1010-2760, e-ISSN: 2071-0054, 11(4): 13-15, 2002. [ Links ]

MOREJÓN, M.Y.; IGLESIAS, C.C.E.; DOMÍNGUEZ, C.G.: ¨Evaluación de los medios de transporte utilizados en el proceso cosecha-transporte del arroz en el Complejo Agroindustrial “Los Palacios”¨, Revista Ciencias Técnicas Agropecuarias, ISSN-1010-2760, e-ISSN: 2071-0054, 21(3): 45-48, 2012. [ Links ]

NC: 34-37: 2003: “Máquinas Agrícolas y Forestales, Metodología para la evaluación Tecnológica y de explotación”, Oficina Nacional de Normalización (NC), La Habana, Cuba, 2003. [ Links ]

NC 34-47: 2003: Máquinas agropecuarias y forestales. Metodología para la determinación de las condiciones de pruebas, Oficina Nacional de Normalización, No. 2da Edición, La Habana, Cuba, 2003. [ Links ]

OLIVET, R.Y.E.; ORTIZ, R.A.; COBAS, H.D.; BLANCO, B.A.; HERRERA, G.E.: ¨Evaluación de la labor de rotura con dos aperos de labranza para el cultivo del boniato (Ipomoea batatas Lam) en un Fluvisol¨, Revista Ciencias Técnicas Agropecuarias, ISSN-1010-2760, e-ISSN: 2071-0054, 21(4): 24-29, 2012. [ Links ]

ORTIZ, A.; GASKINS, B.; PARRA, L.; VÁZQUEZ, H.: ¨Evaluación tecnológica y de explotación de conjuntosde máquinas en la labor de surcado para el cultivo del boniato (Ipomoea batatas, Lam Poir)¨, Revista Ciencias Técnicas Agropecuarias, ISSN-1010-2760, e-ISSN: 2071-0054, 20(2): 11-14, 2011. [ Links ]

SERÉ, C.: ¨Socioeconómica de los sistemas de producción de doble propósito¨, Panorama de la ganadería de doble propósito de la América tropical, Arango, L., Charry, A. y Vera, R. ed. , pp. 13-28, Ed. ICA, Bogotá, Colombia, 1986. [ Links ]

SOTO, E.: ¨La ganadería de doble propósito en Venezuela¨, En: Congreso Venezolano Producción e Industria Animal. AVPA, INIA, UCV, pp. 221-229, Maracay, Venezuela, 2005. [ Links ]

TORRES, A.: ¨Perspectivas de la producción bovina en el estado Trujillo. ¨, Mundo Pecuario, ISSN-1856-111X, 3(1): 14, 2007. [ Links ]

TURITRUJILLO: municipio la Ceiba, [en línea] 2015, Disponible en: https://turitrujillo.wordpress.com/municipio-la-ceiba/ [Consulta: 2 de mayo de 2015]. [ Links ]

VALDÉS, H.P.A.; DE LAS CUEVAS, M.H.R.; RODRÍGUEZ, A.D.; SUÁREZ, L.R.; GÓMEZ, A.M.V.; DELGADO, R.R.: ¨Determinación de los indicadores tecnológicos y de explotación de la máquina picadora de forraje MF IIMA modelo EM-01 modificada¨, Revista Ciencias Técnicas Agropecuarias, ISSN-1010-2760, e-ISSN: 2071-0054, 24(3): 28-34, 2015. [ Links ]

VALDÉS, H.P.A.; MARTÍNEZ, R.A.; PÉREZ, P.: ¨Análisis de la caña de azúcar como alimento para el ganado Sugar cane analysis as livestock food¨, Revista Pre-Til de la Universidad Piloto de Colombia, 10(26): 59-74, 2012. [ Links ]

YARA ARGENTINA: Producción mundial de maíz., [en línea] 2019, Disponible en: https://www.yara.com.ar/nutricion-vegetal/maiz/produccion-mundial/ [Consulta: 17 de agosto de 2019]. [ Links ]

The mention of trademarks of specific equipment, instruments or materials is for identification purposes, there being no promotional commitment in relation to them, neither by the authors nor by the publisher.

Received: December 12, 2020; Accepted: June 18, 2021

*Author for correspondence: Pedro Antonio Valdés Hernández, e-mail: pvaldes@unah.edu.cu

Pedro Antonio Valdés-Hernández, Profesor Titular, Universidad Agraria de La Habana, Facultad de Ciencias Técnicas, Autopista Nacional km 23 ½, Carretera de Tapaste, San José de las Lajas, Mayabeque, Cuba, e-mail: pvaldes@unah.edu.cu

Pascual Daniel Crespo-Torres, Egresado de maestría, Universidad Politécnica Tecnológica del Estado de Trujillo, Estado Trujillo, Venezuela. e-mail: pascual_crespo@yahoo.es

María Victoria Gómez-Águila, Profesora, Universidad Autónoma Chapingo, Departamento de Ingeniería Mecánica Agrícola, Texcoco de Mora, México. E-mail: mvaguila@hotmail.com

The authors of this work declare no conflict of interests.

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