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Walnut blight

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Walnut blight

Bacteria

What is an opportunist?

An "opportunist" is a population (fungi, bacteria, insects…) that takes advantage of a favourable environment to settle in, multiply and feed on it. It often develops when the natural defences of the affected organism are weakened — for genetic reasons or linked to context (water stress, deficiencies, nutritional imbalances, overcrowding…). This is typically the case in monocultures, where a single host plant, uniform and present in large numbers, offers ideal ground for it to spread.

Identification key : Bacterial diseases (Damage and symptoms on the host)

Scientific name : Xanthomonas arboricola pv. juglandis

Other names : Bacterial blight of walnut, Black spot of walnut

Walnut bacterium found in all growing areas. It forms black spots on leaves, catkins, shoots and fruit; infected young nuts drop or blacken and damage can reach the kernel. It overwinters in buds and spreads with rain during flowering.

Crops affected : Walnut tree

Source : Xanthomonas arboricola pv. juglandis (XANTJU)[Overview] — EPPO Global Database — EPPO

This page lists the bio-preparations in the collection that other references associate with this opportunist: Walnut blight.

Warning: the associations between recipes and opportunists come from other references (traditional practices, publications, user feedback). They are neither a recommendation nor a claim of effectiveness. There is no certainty regarding the preparation, application and use of these bio-preparations. See the regulations

No published recipe is associated with this opportunist yet.

See also

Crops

Walnut tree

Opportunists of the same crops

San José scale Codling moth Phytophthora cinnamomi root rot Xylella fastidiosa Common cockchafer (white grub) Walnut husk fly Brown marmorated stink bug

← Referenced opportunists

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