In some areas, weather conditions may impact crop yields
01/15/2025
Prolonged dry spells in key soybean producing regions of southern Brazil are raising concerns among farmers about the performance of the 2024/25 harvest. While crops in Paraná are in their developmental stages, planting in Rio Grande do Sul is nearing completion amid rising temperatures that could surpass 40°C in the coming days.
In a crop monitoring bulletin released earlier this week, Brazil’s National Supply Company (CONAB) reported that soybean fields in Rio Grande do Sul are already feeling the impact of a drought lasting up to 40 days in some areas. In Paraná, dry conditions are affecting crops in their reproductive phase. Nevertheless, CONAB has so far maintained its forecast for the country’s total soybean harvest.
In Campo Mourão, northwest of Paraná state, farmer Wallace Lopes told Valor that his soybean fields have seen no rain for 20 days. “My average yield is 90 sacks per hectare, but I’m forecasting just 60 sacks this season. If it doesn’t rain soon, I think yields will drop to 30 sacks. The plants are stunted due to the heat and will likely lose productivity,” he said.
In Cascavel, western Paraná, where soybean cultivation covers nearly 100,000 hectares, the drought has already taken a toll, according to Paulo Cezar Vallini, director of the local rural union. He estimates a 10% drop in the harvest, which could reach up to 15% in some areas of the municipality. Initial projections put average productivity at 63 sacks per hectare.
Further west in Palotina, the lack of rain is also expected to impact yields, said Edmilson Zabott, president of the city’s rural union. “We’re facing a worrying situation with soybean crops. Farmers here initially expected yields of 70 to 75 sacks per hectare, but now we’ve adjusted that down to 50 to 55 sacks,” Mr. Zabott said.
He noted that rainfall stopped just before Christmas, a critical period for soybean crops requiring water for grain filling. “We didn’t get the regular rainfall we needed, and the heat has been unusually intense,” he said.
Despite farmers’ concerns, Carlos Hugo Godinho, an agronomist with Paraná’s Department of Rural Economics (DERAL), said it is still too early to assess potential losses in the state’s soybean production.
“The current conditions are considered very good overall. The drought’s effects don’t seem alarming for now, as crop maturation is generally uniform,” Mr. Godinho said. However, he acknowledged the situation could change, as widespread rainfall in the state is not expected until January 17.
The northern and western regions of Paraná, where temperatures are higher and rainfall scarce, remain the most concerning. “We’ll have a clearer picture later this week, and it’s possible the conditions recorded initially could worsen,” Mr. Godinho added.
In Rio Grande do Sul, insufficient soil moisture is delaying soybean planting. Rising temperatures are exacerbating the situation.
In areas such as the Western Border, northwest, and northern regions of the state, the lack of rain has stalled planting, which has reached 98% of the planned area. The state’s Technical Assistance and Rural Extension Company (EMATER/RS) has already noted losses in potential productivity.
“I’ve visited some parts of the state, and losses are evident in microregions, expanding with each rainless day. The combination of dry weather and high temperatures is affecting soil moisture, creating challenges even for irrigated areas,” said Alencar Rugeri, technical director of EMATER/RS.
However, Mr. Rugeri emphasized that these conditions are not uniform across the state. “In the Western border, some fields still show good potential. While some areas haven’t seen rain for 40 days, others received significant rainfall,” he said.
In Dom Pedrito, in the far south of the state, the lack of rain has not yet led to soybean losses, according to José Roberto Pires Weber, president of the local rural union. “We haven’t had rain for over 30 days. This could lead to productivity losses, but it’s premature to say for sure. There’s still time for recovery if it rains soon,” Mr. Weber noted.
Mr. Rugeri added that high temperatures are particularly detrimental to crops in the grain-filling stage, which accounts for 25% of the state’s soybean plantings. The productivity of the remaining 75% is still undetermined.
While weather forecasts predict continued heat, Mr. Rugeri urged caution before concluding whether the state’s projected harvest of 21.65 million tonnes will be achieved.
“We’re at a critical point for crop development. It’s impossible to determine the final size of the harvest now. While the outlook is challenging, there’s still room for improvement,” he said.
*By Paulo Santos e Carolina Mainardes — Campina Grande (PB), Ponta Grossa (PR)
(Marcos Fantin contributed reporting)
Source: Valor International