Disease pressure eases in Brazil’s winter tomato season

Tomato fields in southern Minas Gerais, Brazil, face elevated bacterial disease pressure during the first phase of the 2026 winter season, after above-average rainfall hits the region between mid-January and the first half of March, according to a report by Bruna Odebrecht and João Paulo B. Deleo for hfbrasil.org.br.

The wet conditions drive outbreaks of bacterial speck (Pseudomonas syringae) and bacterial spot (Xanthomonas) across the area. To limit the damage, many growers delay transplanting operations originally planned for the first week of March, pushing them back to the second week of the month. Despite those difficulties, the first harvests in March, from fields transplanted in January, produce yields of between 350 and 400 boxes per 1,000 plants.

From April through June, cooler temperatures and reduced rainfall bring bacterial disease pressure down considerably. Isolated cases of late blight (Phytophthora) appear due to the cooler weather, but the disease stays under control and causes no significant production losses. Fields transplanted between February and March, whose harvests begin in April, average around 400 boxes per 1,000 plants as a result.

For July, yields are projected to climb further, reaching between 400 and 450 boxes per 1,000 plants. The report attributes the improvement primarily to the lower incidence of bacterial diseases in fields transplanted later in the season, between the second half of March and April, which are now approaching the end of their production cycle.