БFSA develops a strategy for the protection of orchards against the pest black buprestid

The Bulgarian Food Safety Agency (BFSA) is taking action regarding the increasing population of the Mediterranean flat-headed root-borer (Capnodis tenebrionis)*, detected in 2024. The problem was identified already during the active vegetation season, and in order to promptly establish the current condition of the orchards in the country, the BFSA sent letters to the Regional Food Safety Directorates.

The problem with the Mediterranean flat-headed root-borer is not limited only to Bulgaria. The pest is also observed in other European countries, with an overall regional trend of increasing population. This underlines the need for timely measures to control and limit its spread.

In 2024 a gradual increase in the population density of the Mediterranean flat-headed root-borer is being observed. The reasons for this are complex and include:

- Problems in the applied agronomic practices – lack of resistant rootstocks; maintenance of the soil surface permanently grassed and lack of gravity irrigation; use of planting material from certified nurseries;

- Climate change – the warming of the climate directly affects the development of the insect – high survival rate and short development time of overwintering larvae, extension of the period of adult dispersal, and consequently higher fertility and mass increase of the population to large proportions.

- Lack of developed effective tools for monitoring the pest – there are no pheromone traps, coloured sticky traps, sensor and digital methods.

- Limited range of authorised active substances in plant protection products (PPP) at European level related to the reduction of pesticide use and the Green Deal, and lack of effective alternative means of control.

Prevention and the application of high-level agronomic measures remain the basis of effective pest control. Pursuant to the Plant Protection Act, the protection of plants and plant products is carried out through the general principles of integrated pest management. All persons are obliged to maintain in good phytosanitary condition the plants and plant products which they own, grow, produce or store.

Measures for the control of the Mediterranean flat-headed root-borer are undertaken as soon as temperatures rise in spring. Plant protection products with different modes of action, including those containing microorganisms, are applied against the adults. For the larvae, biological control agents such as entomopathogenic nematodes and PPP containing microorganisms are used.

The BFSA has taken all necessary steps to authorise the use of biological control agents and PPP, as well as to develop a strategy for the control of the Mediterranean flat-headed root-borer. Two working groups have been established – one for authorising the use of biological control agents against the larvae of the Mediterranean flat-headed root-borer, and another for drawing up a national strategy for pest control.

We call on agricultural producers to use only planting material with proven origin from certified nurseries, in order to prevent the spread of the pest and to preserve the health of orchards.

*The Mediterranean flat-headed root-borer (Capnodis tenebrionis) has been a dangerous pest of stone fruit species in our country since the 1940s and 1950s. It is widespread in nurseries and young orchards. It attacks apricot, plum, peach, sweet cherry, sour cherry, apricot hybrids, the oil-bearing rose, pear, quince and hawthorn.

The pest develops one generation in two years. The adults feed on the petioles of leaves, buds and bark of the trees. The main damage is caused by the larvae, which penetrate the roots and bore galleries in the main root. As a result of the damage, the trees weaken, dry out and die. The presence of the pest can be established by finding leaves with gnawed petioles under the tree canopy. In cases of severe infestation, the leaves fall off during the summer.

photo: Pixabay

Source: BFSA