Mechanized harvesting of conilon coffee

Studies show that the mechanized harvesting of conilon coffee can have similar efficiency to the operation carried out on Arabica coffee, as long as the harvesters have working frequencies and operating speeds correctly regulated and appropriate for each type of genetic material..

The lack of labor in the field has worried conilon coffee producers. It affects the harvest, increases production costs and makes the product less competitive on the national and international market. There are better working conditions and wages in urban centers and this becomes even more critical during the harvest period, when the demand for workers increases. 

As a consequence, many producers are unable to harvest in the recommended condition, with at least 80% fruit maturity, and need to anticipate to ensure a complete harvest, without major losses. But with a large quantity of grains still green, loss of quality and yield is inevitable. 

To overcome this scenario, conilon coffee producers are looking for alternatives for a more productive harvest and one of them is mechanization. In Arabica coffee harvests – similar crops –, for example, mechanized harvesting has been carried out in an efficient and economically viable way and, despite divergences between plants and management, it is possible to use this same machinery in conilon crops.

Conilon coffee has particularities such as multiple stems, ranging from three to five orthotropic branches, less erect plants, planting of clones in a row, cross pollination, more superficial root system, absence of fruit falling after physiological maturation, crops cultivated in more hot and with an altitude of less than 500 meters. All these morphological characteristics, added to the current management adopted, make it difficult to use mechanized systems, frequently applied in the harvesting of Arabica coffee. However, solutions and opportunities came from management adaptation studies and technical and economic feasibility.

In agricultural production, harvesting is a stage that stands out due to the high investment involved and the financial returns obtained through the commercialization of crops. Currently, it is one of the most important stages of the harvest, and year after year it depends on technology to be competitive. The main benefits of mechanized harvesting are better quality products, reduced losses during harvest and the possibility of increased profits. 

In Arabica coffee plantations, a reduction in the total cost of mechanized harvesting is estimated to be up to 60% compared to manual harvesting. These levels of cost reduction were only possible because of adaptations made to machines and crops in recent years to increase efficiency and minimize losses.

Aware of the need to generate positive results also in conilon coffee harvests, the first field trials were started with a Case IH self-propelled harvester in commercial crops in traditional planting and planting prepared for mechanized harvesting, between 2013 and 2016, in the north of the state of Holy Spirit. The objective was to evaluate technical indices of mechanized harvesting under different management conditions. 

The first tests were carried out in traditional planting crops, with three to four stems (orthotropic branches) per plant and spacing 3-3,5 x 1m (Table 1). The machine showed stripping and harvesting efficiency ranging from 85% to 93% and 70% to 78%, respectively – levels slightly lower than those achieved when harvesting Arabica coffee. The loss of ground ranged from 10% to 21%, due to the fact that the crop has multi-stemmed plants (with three to five stems) and arched, reducing the sealing of the reception system, creating spaces for fruit to fall to the ground. In general, the conilon coffee tree does not show a natural fall of ripe fruits to the ground, as occurs with arabica, which favors harvesting and harvesting efficiency and, consequently, minimizes crop losses.

In some situations, collecting the volume of fruits from the ground is considered viable for the Arabica coffee tree, depending on the volume and operational cost. Studies indicate that the efficiency of collection systems can vary from 50% to 85% for Arabica coffee, depending on the systematization of the land. Thus, because the productivity of conilon coffee is higher than that of arabica, the use of floor collectors can be an alternative to increase the efficiency of the mechanized system.

These results in traditional crops were promising, although lower than those normally obtained in Arabica coffee crops. It is worth noting that the crops were not prepared for the harvesters, with the presence of irregularities in the terrain, plants with uneven growth and falling over, and, in some cases, there was no uniformity of fruit maturation in the row. In these tests, the configuration of the machines, the number of passes of the machine on the line, the harvesting speed, the frequency of shaking, the degree of ripeness of the fruits and the architecture of the plants changed the stripping and harvesting process, requiring adjustments. specific to each crop condition.

In a second step, evaluations were carried out on crops suitable for mechanized harvesting (according to Table 2), aiming to improve technical indices. Selected clones with characteristics of interest for mechanized harvesting were planted in alternating rows with a spacing of 3,2-3,5 x 0,5m and two stems per plant. 

In tests carried out on prepared crops, stripping and harvesting efficiency was found to vary from 85% to 97% and from 75% to 87%, respectively, with an average higher than tests carried out on traditional crops (Table 1). Floor losses in prepared crops were 10% to 14%, that is, they were reduced in relation to tests previously carried out in traditional crops. The results were positive and similar to those achieved in the harvesting of Arabica coffee, which indicates the feasibility of using these harvesters also to harvest conilon coffee.  

Currently, loss levels in the Arabica coffee tree are 6% to 8% due to the improvements that were implemented in the collection system of the Case IH harvester year/model 2018. It is estimated to obtain the same for conilon in crops systematized for harvesting mechanized. Even with the reduction of losses to the ground, soil collection may be viable for the conilon coffee tree, which requires further operational and economic studies. 

Studies on the mechanized harvesting of conilon coffee indicate the efficiency of the operation is similar to the operation carried out on Arabica coffee, as long as the harvesters have working frequencies and operating speeds correctly regulated and appropriate for each type of genetic material. Therefore, it is essential for the success of mechanized operations to adjust these settings, as well as technically define the characteristics of the crop and the ways of managing the conilon coffee tree.

The results indicated technical feasibility for the use of self-propelled harvesters in conilon coffee plantations, with potential for application in commercial areas. However, changes in plant management are necessary, such as the one proposed in Table 2, in relation to traditional management, for greater harvest efficiency and reduction of fruit losses in the soil. Likewise, future studies are also necessary to improve technical indices, in addition to monitoring possible seasonalities in plant productivity, ensuring the longevity of crops and the sustainability of production.

Gustavo Soares de Souza, José Antônio Lani, Incaper; Mauricio Blanco Infantini, CNH Industrial

Article published in issue 184 of Cultivar Máquinas, May, 2018.