Dactylonectria estremocensis

Dactylonectria estremocensis is a pathogenic fungus that belongs to the Nectriaceae family. It is a significant agent associated with the complex of diseases often referred to as "black foot" disease or vine decline in vineyards. This pathogen is increasingly recognized as a major limiting factor in the establishment and longevity of new grapevine plantations worldwide.

The primary host for this fungus is the Vitis vinifera grapevine. The pathogen targets the roots and the basal parts of the vine. It acts as a vascular pathogen, colonizing the xylem and phloem, which progressively destroys the vine's ability to transport water and essential nutrients from the roots to the canopy.

Symptoms of the infection typically include stunted growth, chlorotic leaves, and a general lack of vigor. As the disease progresses, growers often notice a reddish-brown or black discoloration of the root tissues and necrotic lesions on the base of the trunk. In severe cases, the infected vines show signs of sudden collapse during the peak growing season.

The development and spread of Dactylonectria estremocensis are strongly favored by abiotic stress factors, such as waterlogged soils, poor drainage, and mechanical injury to the root system during planting or nursery operations. The fungus persists in the soil and can be introduced into new fields via infected propagation material, making early detection vital.

Integrated management is essential for controlling this disease. This includes strictly sourcing high-quality, certified nursery stock and implementing pre-planting fungicide dips if permitted. On a farm level, managing soil health, avoiding site compaction, and disinfecting pruning tools between vines are critical preventative measures to reduce the inoculum pressure in the vineyard environment.