The whole hazelnut world has united against the brown marmorated stink bug
By Gian Paolo Ponzi
The whole hazelnut world has united against the brown marmorated stink bug. This global threat is spreading not only in Italy, but in all the world’s leading production areas from Oregon to Turkey, and from Spain to Georgia. The solution is inspired by the ideas and experiences of researchers. Edagricole networked the most brilliant specialists in this issue in a multilingual international webinar, which offered the opportunity for an enriching discussion between leading research centres, from Oregon State University to the Georgian National Food Agency, from Ondokuz Mayis University in Samsun, Turkey, to the University of Turin, a global landmark for the development of innovative and environmentally friendly pest control methods.
Brown Marmorated Stink Bug on Hazelnut plant (Tavella’s picture)
Carl Atkin
The supply chain’s united front
The event, chaired by Terravost’s British journalist Carl Atkin, provided deep insights into the current situation of parasitoids and symbiotic control, monitoring systems, and all initiatives implemented around the world to limit the progress of a non-native insect capable of causing massive damage to the yield and quality of hazelnuts.
Lorenzo Tosi from Edagricole says, «The brown marmorated stink bug is a subtle and difficult adversary to challenge. Unfortunately the hazelnut does not escape its attacks. Indeed, damage to this cultivation can be serious because it can impair the organoleptic quality of processed products».
However, the non-native insect, which arrived from the east, has found a professional and fully equipped hazelnut production chain in Italy to combat it.
«In fact, in recent years our hazelnut production has been profoundly renewed with the creation of new districts throughout the peninsula, besides closer cooperation between institutions, nurseries, and the world of research and production». The change has been triggered by strategic plans, such as the one promoted by Ferrero HCo. «Edagricole, a historic publisher specialising in agriculture, has followed these developments by providing all its support in terms of training and information».
Pino Calcagni
Consumers demand quality
«INC (International Nut & Dried Fruit) has been committed to the development of the nut and dehydrated fruit industry for over 40 years,» as stated by Pino Calcagni who, along with the Besana Group, is among the founders of this association. «Our mission is to supply high quality nuts to 3 billion consumers worldwide by implementing a powerful expansion plan». Hazelnut is a particularly fast-growing industry, with production recording nearly 600 thousand tons. «Consumers demand a high quality product, and INC has launched a global project to counter the damage caused by the brown marmorated stink bug, together with internationally-renowned scientists».
Eric Schlesinger
Ferrero HCo’s commitment
Eric Schlesinger of Ferrero HCo said, «We are living in an important historical moment for the hazelnut industry. It is a key cultivation for us, since 65% of our Group’s turnover comes from products based on this ingredient». Ferrero Hazelnut Company was established in 2015 to protect the production line and manage the value chain starting from cultivation.
«The goal is to encourage the development of high quality supply chains around the world».
Three action areas
Our action targets three different areas, precisely, improving operating conditions by defending good and fair working conditions throughout the value chain; improving production sustainability by adopting a regenerative agricultural approach; and managing supply chain transparency with digital flexibility to enhance the contribution of every link in the value chain, starting with nurseries and growers». In its 7 factories based on 4 continents, Ferrero analyses more than 100 quality parameters to ensure high standards for consumers around the world, In recent years the need to prevent damage, especially to quality brought about by Halyomorpha halys attacks, has become increasingly important.
A centre of expertise to carry the industry into the future
Eric Schlesinger went on to explain, «The Agri Competence Centre created by us to support the transition to the agriculture of the future has six different divisions (Genetic improvement and propagation, Data science, Pest and pathogen protection, Agricultural technologies, Agronomic practices and sustainability). It supports dozens of projects with leading scientific institutions around the world».
Luciana Tavella
A parasitoid resource
The scientific reports commenced with a presentation on egg parasitoids of the brown marmorated stink bug by Luciana Tavella from the Department of Agricultural, Forestry and Food Sciences at the University of Turin.
She said, «Traditional agrochemical defence strategies have not proven to be the most effective way of combatting the bug. Instead, parasitoids of the genus Trissolcus, which are present in the bug’s native area, have been the most specialised and efficient means of counteracting it.» Particularly in Italy, Trissolcus japonicus has been the focus of a national biological prevention project with controlled releases starting in 2020.
Conversely, native generalist parasitoids, such as Anastatus bifasciatus, have shown rather poor parasitising efficacy in the range of 0-11.3%.
Specialised exotic parasitoids, such as T. japonicus and the congener T. mitsukurii, were found to be naturally present in Italy since 2018.
«Surveys conducted in 2020 and 2021 in Piedmont show a progressive increase in bug eggs parasitised by species of the genus Trissolcus».
Celal Tuncer
Two points of entry into Turkey
Celal Tuncer, from Ondokuz Mayis University in Samsun, Turkey, has studied the latest developments in brown marmorated stink bug control in this country. «Probably BMSB (brown marmorated stink bug) entered Anatolia from two different entry points, precisely Georgia to the east, and the Black Sea to the west».
«Today there are reports in 10 provinces, but areas presenting the highest population are those most suitable for hazelnut production, in the north east, bordering Georgia (Arvin and Rize)». Damage is not yet significant but the Ankara government has defined a monitoring plan based on pheromone traps, starting in 2018. To date, only some areas have implemented control strategies based on the use of pyrethroids. Some tests have, instead, verified and ascertained the efficacy of entomopathogenic bacteria against the bug. The first report of parasitised BMSB eggs was in 2021, in Samsun, but it involved the action of Anastatus bifasciatus.
The Ministry of Agriculture recently approved the importation of T. japonicus in view of launching a national biological control plan in this country too.
Nikoloz Meskhi
Massive damage in Georgia
Nikoloz Meskhi, head of the Plant Protection Department of the National Agency of Georgia reported that, already in 2016, the brown marmorated stink bug caused significant damage in this country not only to hazel trees but also to corn and other fruit and vegetable species. «Estimated losses reached $60 million dollars». The Tbilisi government’s response involved setting up monitoring activities (with 6 thousand traps), phytosanitary management of the infestation, and scientific research.
The efficacy of pyrethroids, bioinsecticides (Beauveria bassiana and natural extracts containing Azadirachta indica and pyrethrins) and Attract and Kill traps was tested. The positive contribution of two parasitoids belonging to the local entomofauna, precisely Anastatus bifasciatus and Trissolcus belenus, was observed.
In order to study and develop different and more appropriate biological control strategies, a dedicated laboratory was established in the western part of the country.
Nik Wiman
Strategies adopted in Oregon
Even before it was detected in Europe, the brown marmorated stink bug made its appearance in the United States, where it soon became a problem for hazelnut production on the West Coast.
Nik Wiman of Oregon State University says, «We have known about the problem since 2014. The impact on hazel tree cultivation has definitely been significant». Studies have shown variable degrees of damage depending on the number of adults present in the facilities. «The presence is initially concentrated on the edges of hazelnut groves, and then also inside them, with a peak in presence and damage at the end of the season». Countermeasures developed to combat this phenomenon are especially based on integrated pest management strategies using various formulations, which are also effective against aphids. Some biological control trials, on the other hand, produced controversial results due to treatments that were not compatible with the parallel aphicidal strategy. «An improvement was observed with proper timing of interventions. This was achieved by monitoring with pheromone traps». Classical biological control strategies have also been organised in Oregon. «The discovery of parasitised eggs, a result of previous T. japonicus releases, allows us to expand this strategy. In 2021 T. japonicus was released in 94 sites, and the effectiveness of this action is still being assessed».
Elena Gonella
The novelty of symbiotic control
Symbiotic control is an entirely innovative control strategy, theorised and studied for the first time in the world by Disafa of the University of Turin. Elena Gonella explains, «Bugs host primary intestinal symbionts that are necessary for their survival. Halyomorpha halys does not escape this rule». Soon after hatching, the neanids remain on the eggs for a period of time in order to acquire the bacterium Pantoea carbekii. Bactericidal treatment of egg clusters has proven effective in preventing the development of H. halys populations.
The best results were observed by applying a fertiliser containing copper and zinc salts complexed with citric acid. «Tests performed over several years have confirmed its efficacy and selectivity against oophagous parasitoids and natural predators». In traditional hazel groves, the strategy developed in Turin integrates this treatment, which is positioned after careful monitoring, with an insecticide for pest control when adults appear. Instead, for organically managed hazel groves, only the bactericide is applied, always when the temperature threshold of 18°C is exceeded, with 4-5 treatments every 10 days.
Tommaso De Gregorio
The bug’s southward progress
Webinar attendees addressed several questions to the speakers towards the close of the event. Questions were also asked by people operating in hazelnut production areas where the presence of the bug does not pose problems as yet, such as Chile. After initial reports in the Santiago area, it appears that the bug did not spread to neighbouring areas. However, Luciana Tavella warned Chilean farmers: «The country’s climatic conditions are favourable to the bug. Even in Italy it took 7-8 years of ‘acclimatisation’ to go from the early reports to the actual presence of damage».
As for Italy, answering a question concerning the insect’s presence in the Central South, Tommaso De Gregorio, head of Ferrero HCo’s Agri Competence Centre, reported a considerable increase in catches in the Campania region, while the presence of the bug appears to be better controlled in Lazio. However, the situation is closely monitored.
Sustainable solutions for the development of regenerative agriculture
De Gregorio reassures, «Hazel growers can count on the support of Ferrero, which will continue to stand by them in researching and developing measures to combat the brown marmorated stink bug. We continue to invest in innovation projects around the world to identify the most effective solutions that can be adopted in different geographical areas».
He briefly concluded, «Considering the importance of this adversity on the hazelnut value chain, Ferrero is particularly committed to finding sustainable solutions to reduce the environmental impact of the fight against the brown marmorated stink bug, with a view to applying a regenerative and sustainable agricultural model».
