Lobesia botrana, also known as grapevine moth, is a pest which seriously affects vineyards. The moth has a life cycle of several generations over the course of the vine’s fruiting season, with its larvae perforating the grapes to feed on them, causing direct losses of harvest. Aside from the direct damage, the perforations allow the entry of such pathogens as the Botrytis cinerea fungus which causes grey mould, along with other impacts. Aside from reducing the quantity of grapes harvested, the indirect damage and reduction in wine quality result in very substantial financial losses for growers.

An efficient, biological and residue-free solution

Belthirul is a biological solution with phytosanitary registration in various countries around the world, formulated on the basis of the microorganism Bacillus thuringiensis var. kurstaki strain PB-54, exclusive to Probelte, selected for its effectiveness in controlling Lobesia botrana and other pest moths, without leaving any residue. Its action is based on the effect of different CRY and VIP toxins (generated in the fermentation process specifically designed for the PB-54 strain). These toxins form a characteristic crystal which, when ingested by the larvae of the grapevine moth, are dissolved and activated in the alkaline environment of the intestine. When the proteins are activated, they bond to the inner wall of the moth’s intestine, forming pores in the larva’s intestinal wall, causing paralysis of its digestive apparatus, which results in the insect’s death. This specific action ensures that only the larvae of susceptible insects, such as Lobesia botrana, are affected, without harming other beneficial organisms.

Application of Belthirul is as simple as it is effective. It is sprayed directly onto the leaves and bunches of grapes, to which the crystals of the microorganism adhere. When the Lobesia larvae feed on the treated parts of the plant, they ingest the proteins which are toxic to them, stop feeding, and die in a few hours. Belthirul is formulated with UV radiation protectors, which avoid degradation of the crystals, making the product long-lasting and more effective in comparison with other Bacillus thuringiensis strains used in competing products. It also contains substances which increase palatability, so that the larvae ingest the product more quickly, speeding up its insecticide process.

Unlike many chemical pesticides, Belthirul has no safety interval and leaves no residue on the grapes, on the plant or on the soil, making it a safe option both for consumers and the environment. Belthirul is compatible with integrated pest management (IPM) programmes, integrating perfectly with other sustainable agricultural practices, allowing use in combination with other biological and cultural control methods, and avoiding pest resistance. Lastly, it not only provides an effective solution to control Lobesia botrana, but also supports a sustainable and environmentally friendly viticulture.

Case study: field results of Belthirul

To test the effectiveness of Belthirul, numerous trials were conducted for registration purposes, one of which involved a Chardonnay vineyard in Castel Boglione, Italy. This evaluated the effectiveness of Belthirul in Lobesia control, comparing its results against an untreated vine control plot, demonstrating the product’s effectiveness in terms of vine yield.

The efficacy of Belthirul was evaluated by comparing plots treated with different concentrations of the product, and an untreated control plot. The results demonstrated that the plots treated with a dose of 1 kg/ha of Belthirul revealed just 4% of the bunches of grapes affected, compared with 35% on the untreated plots. This represents a control efficacy in excess of 90%.

Reducing the seriousness of the pest

Furthermore, another positive aspect demonstrated during the trial is connected with the severity of the damage caused by Lobesia, which was also significantly lower on the plots treated with Belthirul.  On the untreated control plot, an average of 128.5 damaged grapes were observed in a total of 50 bunches. In comparison, the plots treated with 1 kg/ha had 9 grapes affected in 50 bunches.

The results of the trial indicate that Belthirul is a highly effective product in controlling Lobesia botrana in vines, reducing both the percentage of bunches affected and the seriousness of the damage to the vineyards.

With control efficacy in excess of 90%, without leaving any chemical residue, Belthirul is a safe and sustainable solution for grape growers, supporting responsible and sustainable agricultural practices, while ensuring high-quality grape production.