{"id":40098,"date":"2025-10-22T11:58:25","date_gmt":"2025-10-22T11:58:25","guid":{"rendered":"https:\/\/stella-pss.eu\/?p=40098"},"modified":"2025-10-22T12:39:24","modified_gmt":"2025-10-22T12:39:24","slug":"from-wilt-to-knot-addressing-major-threats-to-greek-olive-trees","status":"publish","type":"post","link":"https:\/\/stella-pss.eu\/fr\/from-wilt-to-knot-addressing-major-threats-to-greek-olive-trees\/","title":{"rendered":"From Wilt to Knot: Addressing Major Threats to Greek Olive Trees"},"content":{"rendered":"
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Tackling Verticillium dahliae and Pseudomonas savastanoi pv. savastanoi<\/b><\/em><\/span><\/h6>

Par Spyridoula Dimitropoulou | Research Associate | AUA<\/i><\/b><\/p>

Olive groves are a key element of the Mediterranean landscape and heritage. In Greece, olive cultivation has a long-standing tradition, widespread across the country and still maintained in many rural regions. Olive production is vital to both the Greek economy and cultural identity, with Greece ranking among the top global producers of olives and olive oil. Yet, the industry <\/span>faces growing challenges<\/b> due to emerging pests and diseases that threaten both yield and quality. Among the most significant pathogens in Greek olive groves are <\/span>Verticillium dahliae<\/span><\/i>, the causal agent of Verticillium wilt, and <\/span>Pseudomonas savastanoi<\/span><\/i> pv. <\/span>savastanoi<\/span><\/i>, which causes olive knot disease.<\/span><\/p>

The challenge of olive tree diseases in Greece<\/b><\/span><\/h6>

In areas such as <\/span>Attica<\/b> et <\/span>Atalanti<\/b>, olive growing plays a <\/span>vital role in local economies<\/b>, with around <\/span>22,212 olive holdings <\/b>spanning roughly <\/span>23,521 hectares in Attica alone<\/b>, providing income and employment for thousands of people involved in olive cultivation and production [1]. The ongoing expansion and intensification of olive farming have brought substantial shifts in cultivation methods aimed at boosting productivity. However, the dominance of monoculture systems, coupled with the accelerating effects of climate change, has heightened the vulnerability of olive trees to both soil-borne and airborne pathogens across Europe [2]. In Greece, these uniform planting practices, together with the region\u2019s typical Mediterranean climate – characterized by hot, dry summers and mild, wet winters – create highly favorable conditions for pathogen development and spread, increasing the impact of diseases such as Verticillium wilt and olive knot.<\/span><\/p>

Verticillium dahliae<\/i><\/b> and Verticillium Wilt<\/b><\/h6>

Verticillium dahliae<\/span><\/i> is <\/span>a soil-borne fungus<\/b> that invades the olive vascular system, disrupting water and nutrient transport in olive trees, which leads to <\/span>wilting, branch dieback <\/b>and, in severe cases,<\/span> tree death<\/b> [3]. Its ability to survive for long periods of time in the soil and within plant debris forming resistant structures and the limited efficacy of chemical control measures, make this pathogen a problem for perennial tree crops like olive [4]. It spreads through <\/span>contaminated soil<\/b>, <\/span>irrigation water<\/b>, <\/span>cultivation equipment<\/b>, and <\/span>infected plant material<\/b>, and can attack a broad range of cultivated crops across Greece.<\/span><\/p>

As there are no chemical treatments capable of curing infected trees, farmers primarily depend on preventive approaches such as:\u00a0<\/span><\/p>