Climate in Brazil and conflict in Iran change the grain scenario

The escalation of the conflict between the United States and Iran, with the blockade of the Strait of Hormuz and the rise in oil prices, has brought volatility to the agricultural commodities market. According to the Grão Direto Expert Analysis released this Monday (23/6), soybeans are impacted by oil and fertilizers, while corn is affected by ethanol plants. In Brazil, the favorable climate for soybeans contrasts with the delay in the second-crop harvest, increasing pressure on logistics and prices. Check out the full analysis:

How did the soybean market behave?

Harvest and weather remain favorable: In the United States, the weather continues to help crops develop well, despite some regions experiencing excessive rainfall. In Brazil, the harvest continues to progress, with stable weather in most producing regions, especially in the center-north.

US attack on Iran: Last week the US attacked Iranian nuclear facilities, opening the way for oil volatility, considering that Iran has control over the Strait of Hormuz, through which a significant portion of the world's oil passes.

Economy: the increase in the Selic rate to 15% by Copom last Wednesday (18) pushed the dollar to the lowest levels in the last 10 months. The more favorable exchange rate helped to contain soybean prices in the domestic market.

In Chicago, the July 2025 soybean contract closed at US$ 10,67 per bushel, down slightly by 0,09% on the week. The March 2026 contract rose by 0,84%, closing at US$ 10,85 per bushel. The dollar fell by 0,36%, closing the week at R$ 5,52. In the physical market, prices continued the downward trend, with declines recorded in most regions.

What to expect from the soybean market?

The conflict and oil: After the United States attacked Iranian nuclear facilities, hitting three of the country's major uranium enrichment centers: Fordow, Natanz and Isfahan, Iran announced the blockade of the Strait of Hormuz, one of the most sensitive points in global energy trade. Around 20% of the world's oil and 25% of its liquefied natural gas flow through this maritime corridor, located between the Persian Gulf and the Gulf of Oman. The military offensive and the blockade of the strait caused a sharp increase in oil volatility, which should have a direct impact on soybean oil prices at the opening of this week, given the correlation between the markets.

The conflict and fertilizers: In addition to being one of the largest oil producers, Iran is also one of the world's leading exporters of nitrogen fertilizers, with an annual production of nearly 7 million tons and estimated exports of 5 million. These fertilizers are widely used in Brazilian agriculture. With the escalation of the conflict, the risk of an increase in international fertilizer prices and logistical difficulties on export routes increases, which could further pressure production costs for rural producers in Brazil. The biggest concern is the effect on nitrogen prices, which had already been on a recovery trajectory since the beginning of May.

Exchange rate and uncertainties: with the increase in the Selic rate to 15%, there was an increase of 0,25 percentage points. Under normal conditions, this would tend to strengthen the real against the dollar, by attracting foreign capital. However, the movement was overshadowed by global uncertainties caused by the conflict in the Middle East. International investors are prioritizing assets considered safer — such as US Treasury bonds — which leads to the appreciation of the dollar, even with high interest rates in Brazil.

Given this scenario, soybeans tend to start the week with an upward trend on the international market, driven by Chicago. In Brazil, however, producers should be cautious: rising costs could offset any possible price gains. The focus, therefore, should be on the exchange rate and oil movements, which should dictate the pace of the market in the coming days.

How did the corn market behave?

2025 Second Harvest: The harvest of the second corn crop continues at a slow pace in Brazil, but Conab technicians have indicated higher productivity than initial estimates in some areas of Mato Grosso, which could impact the final production expectation.

Demand from ethanol plants: The recent rise in fuel prices has improved the margins of corn-based ethanol plants, strengthening their competitiveness in purchasing the grain. This movement contributed to more active demand from the industry, offering support to corn prices throughout the week.

American harvest: In the United States, the weather remains favorable, with an increase in the corn area classified as good or excellent. Crops continue to develop as expected, which limits more significant gains in prices, even with the external environment of pressured costs.

In Chicago, the July 2025 corn contract closed at US$4,29 per bushel, down 3,6% on the week. On the B3, the July 2025 contract also fell, closing at R$63,07 per bag, down 0,44%. In the physical market, prices followed suit and also fell.

What to expect from the corn market?

Oil price hike: The escalation of the conflict in the Middle East caused an immediate rise in international oil prices. This movement directly benefits corn-based ethanol plants, which now operate with more favorable margins. In periods of rising fossil fuel prices, as is the case now, ethanol consumption tends to increase, favoring the competitiveness of biofuels compared to gasoline. With better margins, plants can increase their purchases in the domestic market, acting as a restraining factor on the volumes available for export. This stronger domestic demand, albeit occasional, can help to mitigate the downward pressure on corn prices caused by the arrival of the harvest on the market. It is worth remembering that corn ethanol has been gaining representation in the Brazilian consumption matrix.

Late harvest: The harvest of the second crop continues at a slow pace. As of June 20, only 14,08% of the total area had been harvested — well below the level at the same time last year (37,57%) and also the average of the last 5 years (26,76%). The data indicate that this is the harvest with one of the lowest advances ever recorded for this period, setting off a warning sign.

Rainfall on the radar: Weather forecasts indicate rain for June 23 and 24 in key regions such as Mato Grosso, Goiás, Paraná, São Paulo, Minas Gerais and Mato Grosso do Sul, which together account for around 90% of the second crop production. Since 61,2% of the crops are currently in the maturation phase, this rain could increase grain moisture, making harvesting difficult and affecting product quality. The delayed harvest combined with high production expectations puts pressure on storage capacity in several regions. This situation could lead to overlapping harvests, making it difficult to transport corn and increasing drying and storage costs. Logistics will be a key factor in the coming weeks, especially to avoid conflicts with other products, such as remaining soybeans.

The possible recovery of ethanol plants, stimulated by the rise in oil prices, could provide some additional support to prices in the short term. Even so, the market should remain volatile, with regional fluctuations marked mainly by the evolution of the harvest and the pace of domestic purchases.