Hortifrútis: como controlar pinta-preta? | Impulso Negócios EP. 156

Summary

The video discusses the challenges faced by fruit and vegetable producers, particularly the impact of Black Spot disease, caused by the Alternaria fungus. This disease, common in open-field tomatoes, thrives in warm, humid conditions and can severely affect production. Key factors include plant stress, poor soil, and improper cultivation practices. The video provides preventive measures such as selecting healthy seeds, using fungicides, crop rotation, and soil coverage. It also highlights the importance of controlling the spread through proper farm management and using modern fungicides like bixafen to ensure long-term crop health and productivity.

Takeaways

• 😀 The black spot disease, caused by the Alternaria fungus, affects several fruits and vegetables and is a major challenge for horticultural producers.
• 😀 Black spot is especially common in open-field tomato cultivation and less common in protected environments.
• 😀 The disease thrives in temperatures between 22 and 32°C, with high humidity and alternating dry and wet periods.
• 😀 It is more severe during rainy summers but can also occur in winter in many regions.
• 😀 Plants facing nutritional imbalances, stress from viruses, nematodes, pests, or poor soil are more vulnerable to the disease.
• 😀 Alternaria fungi can survive between crop cycles on leftover crops or in soil, potentially infecting other vegetables like potatoes and eggplants.
• 😀 These fungi can remain viable for up to two years in low humidity, and they spread when environmental conditions are favorable for germination and infection.
• 😀 Infected plants show symptoms 6 to 7 days after infection, with initial signs appearing on the leaves.
• 😀 The black spot disease spreads primarily through contaminated seeds, seedlings, rainwater, irrigation, and human activity.
• 😀 Effective prevention measures include selecting appropriate planting areas, using healthy seeds and seedlings, crop rotation, and applying fungicides.
• 😀 Fungicides like Bixafen, from the carboxamide group, are highly efficient and offer long-term control against the disease, helping optimize tomato, potato, grape, and apple production.

Q & A

What is 'pinta preta' (black spot) and what causes it?

Pinta preta is a disease caused by the fungus *Alternaria*, commonly affecting fruits and vegetables, especially tomatoes, in open-field cultivation.

Why is 'pinta preta' most common in open-field tomato cultivation?

The disease thrives in open fields because of environmental factors such as high humidity and temperatures between 22-32ºC, which create ideal conditions for the fungus to spread.

How do temperature and humidity affect the spread of 'pinta preta'?

The fungus causing 'pinta preta' spreads most effectively in conditions of high humidity and temperatures ranging from 22 to 32ºC, and it can also spread between dry and wet periods.

Can 'pinta preta' occur during the winter?

Yes, although more common in the summer during rainy periods, 'pinta preta' can also occur in the winter in certain regions, especially in plants under stress.

What makes plants more vulnerable to 'pinta preta'?

Plants that suffer from nutritional imbalances, pest infestations, or are grown in poor soil with low organic matter are more susceptible to 'pinta preta'.

How does the fungus *Alternaria* spread?

The fungus spreads through contaminated seeds, seedlings, wind, rainwater, irrigation, and farming equipment, as well as through crop residues between cultivation cycles.

What are the primary preventive measures for 'pinta preta'?

Primary preventive measures include choosing suitable planting areas with good air circulation, using healthy and treated seeds, rotating crops, and using resistant plant varieties.

What role does crop rotation play in controlling 'pinta preta'?

Crop rotation, particularly with non-host plants such as grasses or legumes, helps break the cycle of infection and reduces the spread of *Alternaria*.

Why is the fungicide bixafen important for controlling 'pinta preta'?

Bixafen is an effective fungicide with a new mode of action, offering long-lasting control against *Alternaria* and optimizing crop productivity in affected plants like tomatoes, potatoes, grapes, and apples.

What is the significance of soil management in preventing 'pinta preta'?

Incorporating crop residues into the soil and using soil mulch helps reduce the presence of alternative hosts for *Alternaria*, thus preventing the disease from spreading.