Genetics and correct wheat management save up to R$400,00 per hectare

Study conducted by Embrapa Wheat (RS) and the Cooperative Technical Network (RTC/CCGL) in Rio Grande do Sul showed that the association between quality genetics and efficient management of wheat crops is capable of reducing production costs by approximately R$400,00/ha without harming the productive potential of the grains. The use of cultivars with a high genetic standard offers the producer the possibility of adjusting the volume of seeds during planting, while optimizing the use of fungicides, maintaining the profitability of the crop.

The research evaluated two lines of wheat management in the 2020 harvest: one aimed at reducing the plant population, and the other with the rational use of fungicides, taking advantage of cultivar genetic factors as allies. The saving of R$400,00 per hectare is the result of the sum of R$140,00/ha in seeds and R$275,00/ha in fungicides. Considering the price of a bag of wheat sold in 2020 (R$ 70,00/bag) and the CEPEA average of 10 years (R$ 40,00/sc), the cost reduction represents the value of 6 to 10 bags of wheat per hectare. 

If the calculation is expanded to the 900 thousand hectares of wheat cultivated in RS in 2020, the savings would reach R$ 360 million with seeds and fungicides, an amount that could be reinvested in technologies capable of promoting the productive potential of crops, such as the use of fertilizers, which in addition to increasing wheat productivity can also be used in subsequent crops, such as soybeans in the summer, improving profitability throughout the production system

Investment in seeds and fungicides has been essential to guarantee wheat productivity. However, both expenditures are profitable up to a limit, when in excess, the supposed benefits can only be transformed into production costs. “Excesses in the use of inputs in certain situations have led to a false image that wheat does not generate income. We want to demystify this belief, proving that it is possible to earn money from wheat cultivation, encouraging producers to invest in the crop assertively”, says the agronomist at Embrapa Trigo, Giovani Faé. 

“With the research, we showed that it is possible to generate income in winter with wheat cultivation, using good genetics, efficient management and the use of quality seed”, summarizes the agronomist at RTC/CCGL, Geomar Corassa.

Plant density does not guarantee greater grain yield

To demonstrate that it is possible to reduce the quantity of seeds per hectare without harming the final yield of the crop, plant population strips were installed in 20 exhibition areas, in 17 municipalities in Rio Grande do Sul (details in table). The cultivar used was BRS Belajoia, installed in areas with three sowing densities: 40, 60 and 80 plants per meter of row. In each location, the total area reached three hectares, allocating one hectare for each population group.

To evaluate the response of grain yield to plant density, the display crops were installed in warmer regions, which suffer more from environmental stress, and in regions with a milder climate, which allow for greater productivity in winter crops. Thus, the research covered the entire northern half of RS (look map), where much of the state's wheat production is concentrated. Sowing followed the calendar indicated by the agricultural zoning for each location, with operations carried out between May 25th and July 27th, at a time considered ideal for expressing the crop's productive potential.

The research showed that the increase in plant density did not represent significant gains in final grain yield, even in different production environments. Average yields ranged from 64 to 67 bags per hectare, but costs almost doubled, going from R$ 234,00/ha at a density of 43 pl/m to R$ 415,00/ha at a density of 76 pl/m . “These results demonstrate that the costs of increasing the volume of seeds did not translate into financial profit”, explains Faé.

Planting logic must be per linear meter, as in soybeans

“In general, the producer has adopted 150 kilos of wheat seeds per hectare, but in soybeans and corn the calculation is made in plants per linear meter. We want to show in this work that the implementation of wheat must also follow this logic of plants per linear meter, and not that of kilos per hectare”, explains the agronomist from CCGL, explaining that the adjustment takes into account the variation in PMS (Weight of a Thousand Seeds ) and germination in batches, which can impact seed volume and reduce production costs. “For the positioning to be assertive, it is important that the producer knows the quality of his seed”, he recommends.

For the Embrapa Trigo researcher, Eduardo Caierão, the producer needs to know the history of the area and the genetic potential of the cultivar he is using to define the sowing density: “The producer tends to invest in a higher density for safety reasons, considering the risks of an unfavorable environment for the crop. Based on the history of the area, such as soil quality, the most recurrent pest and disease problems, associated with climate forecasts, it is possible to define how much risk can be taken by reducing the plant population, adjusting costs both in high productivity scenarios and in a less favorable environment for wheat”, he points out. 

According to the researcher, a very safe average is in the range of 250 suitable seeds per square meter. “It is important to highlight that we are talking about quality seed. We have seen that producers increase the volume of seeds because they do not guarantee quality”, adds Caierão, remembering that the rate of use of certified wheat seed in RS is still low, close to 60%.

The cost of wheat seed in RS was on average R$2,20/kg in the 2020 harvest. Considering the recommended population of 43 pl/m (or 250 seeds/m², around 86 kg/ha), when compared to 150 kg of seeds/ha traditionally used in Rio Grande do Sul crops, the cost reduction reaches R$140,00/ha. In addition to reducing costs, adjusting seed density also reduces the risk of lodging in taller cultivars, allowing for increased doses of nitrogen fertilizers that enhance crop yields.

The reduction in disbursement on inputs may, at first, cause concern for companies and professionals who have historically invested in wheat cultivation. Therefore, before publishing the research, Embrapa Trigo invited seed growers who work in the Gaucho wheat market to discuss the results of the work. For the administrative director of the Association of Producers and Traders of Seeds and Seedlings of Rio Grande do Sul. (Apassul), Jean Carlos Cirino, the topic requires a lot of study and discussion: “It is necessary to make it clear that the plant population recommendation, as well as the complete positioning of the cultivar, is up to the plant breeder. There are several factors and technical implications to arrive at the positioning of a wheat cultivar and its developer is the most interested in being assertive”. 

Embrapa Trigo's expectation is that the reduction in production costs may serve as an incentive to increase the area with wheat in the South Region, also boosting the commercialization of certified seed.

Phytosanitary management

To validate the thesis that it is possible to reduce the number of fungicide applications without losing grain production potential, the research group conducted a trial in five locations in Rio Grande do Sul (Passo Fundo, Cruz Alta, Sarandi, Santa Maria and Campo New), aiming to evaluate the genetic response to phytosanitary management in wheat. This study was carried out with the application of fungicides in subdivided plots with three replications and three treatments: no fungicide, fungicide application focused on ear protection, and four scheduled applications (tillering to flowering). Eight wheat cultivars with representation in commercial areas were used, showing great variation in genetic resistance to the main diseases.

Management in the application of fungicides in experiments:

When evaluating phytosanitary management, variations were observed in relation to genetic health in some cultivars. For example, in Passo Fundo, RS, the best performance was from the Embrapa cultivar, BRS Belajoia, which produced 71 sc/ha even without any fungicide application. In Cruz Alta, RS, there was a response of up to eight sc/ha in productivity when four fungicide applications were used, especially in cultivars more susceptible to powdery mildew. 

In this sense, CCGL phytopathologist Caroline Guterres explains that the result is due to the drier year, under the influence of La Nina, when the predominant disease in the 2020 winter harvest was powdery mildew. When deciding on the number and timing of fungicide applications on wheat, she highlights three points: knowing the cultivar being used and its reaction to the main diseases; understand which diseases can occur depending on environmental conditions; and monitor the crop in order to identify early outbreaks of disease. “By combining these three factors, disease management becomes more assertive and, consequently, more economical”, concludes Caroline.

The trial, which included four fungicide applications throughout the harvest, represented an expenditure of R$390,00/ha – based on pesticide prices in 2020, at a cost of R$25,00/ha for each application. By monitoring the crop, it was possible to make a single application of fungicide, aiming to prevent Fusarium head blight in the head, at a cost of R$ 115,00/ha.

Geomar Corassa, from CCGL, draws attention to the results of the fungicide trial: “It is important to consider that knowledge about the cultivar is fundamental to allow this type of practice. Currently, to obtain high production ceilings, some cultivars require robust phytosanitary packages, while others allow savings. This result was confirmed in the study,” he explains.

“We have to consider that 2020 was a dry year, which did not favor the incidence of fungal diseases. In any case, crop monitoring allows for cost reduction in dry years or more efficient control in wet years”, explains the phytopathologist at Embrapa Trigo, Cheila Sbalcheiro.

Perceptions of the productive sector

To generate the results of the research on cost reduction in wheat, Embrapa Trigo and RTC/CCGL counted on the support of partners from the installation of the crops to the conduct of the experiments and data recording. There were several cooperatives, researchers, producers and technical assistants working in 20 exhibition areas in 17 municipalities in Rio Grande do Sul. See some of the participants' perceptions:

In Sarandi, Rio Grande do Sul (RS), agronomist Nazaré Piran conducted the evaluation in the research area of Cotrisal. “We have been working with producers for 18 years and the recommendation for wheat has always been 150 kg of seeds per hectare, around 400 plants per square meter. But we see that productivity is not increasing. In the same way that in soybeans we had to reduce the population to reach a greater productive potential, I believe that in wheat this adjustment is also necessary”, says Piran, explaining that the reduction in the number of plants can favor photosynthesis, avoiding the competition for light. “Adjustment in the population can reduce production costs or even allocate resources to fertilization”, advises the agronomist. 

Na ZT Seeds, from Cruz Alta, RS, producer Zeca Scapin seeks to restore the economic profitability of wheat using technologies that reduce production costs and crop risks: “Invest in a cultivar with high productive potential, but low resistance to diseases it will not bring profit in wheat, especially in a spring year with severe weather”, warns Scapini, remembering that productivity and production costs cannot rise together, otherwise the final yield will not translate into profit.

In Espumoso, RS, the experiment was conducted by Planeja Agrícola and surprised technical consultant Jeferson Moras: “We were afraid of reducing the population because we always increase the density of winter crops to control the ryegrass infestation in the areas. But we accepted the challenge and were surprised by the result. The BRS Belajoia wheat cultivar allowed a saving of 70 kg of seeds per hectare and presented the same yield as the largest population, in addition to promoting better tillering that quickly closed the space in the crop and helped control weeds”. He also highlights that the positioning of cultivars with a view to adjusting the plant population is essential in the current scenario of rising production costs: “The producer needs to adjust the quantity of seeds for good production within the expectations of each cultivar. This needs to be evaluated on site, within each reality”, he concludes.