Do any plant galls re­quire more than one host?

BBC Wildlife Magazine - - Q & A - Lee Davies

Yes. Re­quir­ing mul­ti­ple hosts is com­mon for galls cre­ated by rust fungi, of which there are sev­eral thou­sand species. Their life cy­cles can be com­plex with sev­eral dis­tinct stages, and they rely on in­fect­ing plant hosts at dif­fer­ent stages. They also tend to be very se­lec­tive as to their host plants.

Gym­nospo­rangium clavari­iforme is one such rust, in­fect­ing ju­niper and hawthorn. In spring, it pro­duces or­ange ten­ta­cle-like struc­tures on ju­niper (which don’t harm the plant). In sum­mer, these pro­duce spores that go on to in­fect hawthorn, caus­ing a yel­low­ish scar­ring on the leaves and galls on the leaves and fruits. It’s these galls that re­lease spores which go on to in­fect ju­nipers, so restart­ing the cy­cle. In­fected hawthorn can and do ex­pe­ri­ence loss in haw pro­duc­tion.

Newspapers in English

Newspapers from UK

© PressReader. All rights reserved.