Potatoes - Acrobat

Potatoes

The potato is the world’s fourth most important food crop, behind wheat, rice and corn. Potatoes are susceptible to many diseases. The causal agents for these diseases include bacteria, fungi, mycoplasmas, viruses, viroids and nematodes.

Late blight

Late blight (Phytophthora infestans), also known as Irish blight, is one of the most devastating potato diseases – if not controlled, it destroys the crop.

Conditions of high moisture and moderate temperatures over several hours encourage development of the disease. Night temperatures of 10ºC to 16ºC and day temperatures of 16ºC to 22ºC are ideal.

Rain, dew, overheard irrigation and high humidity (greater than 90%) can create an environment where disease development is favoured.

Lesions on the leaves and stem become visible as small flecks within a few days of the infection period. These expand to watersoaked, grey-green areas on the leaf. The affected tissue becomes gray to tan in colour and is dry and dead within a few days. Lesions are often surrounded by a halo of lighter green tissue. The disease may also develop on leaf petioles and stem tissue.

Application timing

Acrobat SC should be applied with Polyram 750DF (mancozeb) or Polyram DF as a protectant treatment 7 to 10 day intervals when conditions favour late blight disease development, before the disease is evident.

This information is also available in the Acrobat SC Technical Manual.

Download pages here.

JAMIE WEATHERALD
Agronomist, Jolpac Rural Supplies

Jamie provides advice and services to most of this region’s vegetable growers. Many of his onion and potato growers use Acrobat for the strategic treatment of downy mildew.

"We develop seasonal control strategies with our guys to help them manage downy mildew. It’s so they can be prepared, but also so we can protect the chemistries we have available and avoid the development of resistance," Jamie said.

"Acrobat is one of the key strategic products. We may not use it every year, but when we have high disease pressure it is our number one choice. It has sensational results.

"Because it is so good, and we want to continue using it for the next 20 years, we need to protect it from resistance development. That’s why we take a very tactical approach to its use.

"Having said that, when things are getting hot with downy mildew we know it will work every time. It’s the one product to fall back and rely on."