Apple Tree Decline

Apple tree decline has been spreading in northern Italy for several years. The phenomenon, which began in some orchards in Trentino and Veneto regions, has spread to almost the entire Alpine arc and the pre-alpine belt. 

The problem of apple tree dieback mainly affects young plants and affects more or less extensive areas of the orchard. The plants initially show a slowdown in their vegetative functions, especially during the flowering and post-bloom phase, with browning along the stem, decortication and cracking, except below the graft point where there is often a high level of sucker emission. This is followed by partial or total desiccation of the plant, which can also occur during the fruit swelling and ripening phase. 

Replacing plants does not solve the problem of apple tree decline and almost always the new plants planted after a short time show the same symptoms again.

In the areas affected for the longest time, such as in Valsugana and Val di Non (Trentino region), in some orchards dryness has affected 80 per cent of the plants. 

Apple orchard severely affected by the mortality.

Cracking of the bark along the stem, a typical symptom preceding plant death.

Apple plant dried out during the fruit swelling phase. 

Re-establishment of an orchard with previous apple decline: the problem reappeared after a few months.

Causes of Apple Tree Decline

Researcher Alessandro Mendini has identified the cause of apple tree decline as an energy imbalance between rootstock and scion resulting from genetic manipulation for varietal improvement. Indeed, the inability of the rootstock to meet the needs of the scion creates greater stress on the plant, culminating in the blockage of lymphatic flow.

The use of BioAksxter® has proven effective against the problem for both prevention and remediation.

Indipendentemente dall’areale geografico o dalle diverse tecniche di coltivazione i risultati si riconfermano:

• in orchards where the phenomenon is occurring, intervention with BioAksxter® results in a 90% reduction in mortality;
• in crop renewal and in the replanting of desiccated plants, mortality is reduced by 98% by treating with BioAksxter® from the time of planting;
• in orchards planted in soils that have already been treated for 2-3 years with BioAksxter® or with plants treated during nursery rearing, apple tree decline does not occur;

Examples of resolving Apple Tree Decline with BioAksxter® M31

1) Azienda Agricola Chini Giulio - Segno di Taio (TN) - April 2009: in an orchard that had never been treated with BioAksxter®, 30% of the plants showed the blockage of vegetative functions with decortications and cracks along the stem. Intervention with BioAksxter® restored the orchard by limiting the mortality to 3% of the plants. From 2010 to 2011, the phenomenon affected only 1.2%.

In the adjacent plot, the orchard with plants of the same origin, but treated with BioAksxter® since planting, death affected 0.25% of the plants over three years.

28 April 2009 Azienda Agricola Chini Giulio: 30 per cent of the plants show typical symptoms preceding apple tree decline.

28 May 2009 Azienda Agricola Chini Giulio: same orchard after one month of treatment with BioAksxter®.

2) Azienda Agricola Martin Silvano - Saluzzo (CN) - Red Delicious orchard treated with BioAksxter® from the end of the year of planting: the death rate reached 0.7% of the plants. In two other orchards not treated with BioAksxter® at the same time and with plants of the same origin, the plant loss was 15% and 40% respectively.

Azienda Agricola Martin Silvano, third leaf plant treated with BioAksxter® the year of planting.

3) Azienda Agricola Berti Andrea - Nogaredo (TN) - apple orchard treated with BioAksxter® from the time the plants were planted: mortality was 1.6%. In the orchards realized by other fruit growers, within a 500 metre radius and with the same plants, the death rate was 20%.

4) Azienda Agricola Biada Romano - Lover di Campodenno (TN) - orchard on land long cultivated with BioAksxter®. In three years, despite the high prevalence of the problem in the area and the presence of particularly sensitive varieties, the death rate was 0%.

Azienda Agricola Biada Romano: orchard free of plant mortality, established in a soil already treated with BioAksxter®.