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1. a highly flammable material, such as Greek fire, formerly used in warfare
2. lightning without audible thunder



an infectious disease of tobacco and Indian tobacco caused by the bacterium Pseudomonas tabacum. Wildfire is characterized by the appearance of numerous pale yellow chlorotic spots, reaching 2 cm in diameter, on the leaves and, sometimes, on the sepals and pods. The diseased areas desiccate in dry weather and rot in humid weather, which often leads to the perforation of the leaves. The causative agent of wildfire enters the plant through the stomata and damaged tissues. The bacterium is preserved in dust that has settled in drying sheds or clinged to seeds and to greenhouse stock; it is also preserved in the unrotted remains of a harvest. Wildfire decreases harvests by 40 to 50 percent. Prices for tobacco leaves drop by 80 percent when the leaves are diseased.

Control measures include using liquid disinfectants on seeds, disinfecting greenhouse stock, spraying seedlings with Bordeaux mixture during the phase of two true leaflets, and growing resistant varieties. The application of potash fertilizers and autumn plowing are also recommended.


Grushevoi, S. E. Bolezni tabaka i sistema meropriiatii po bor’be s nimi. Moscow, 1950.
Leonov, I. P., A. G. Petrenko, and G. M. Psarev. Posobie dlia tabakovodov. Moscow, 1968.



(plant pathology)
A bacterial disease of tobacco caused by Pseudomonas tabaci and characterized by the appearance of brown spots surrounded by yellow rings, which turn dark, rot, and fall out.
References in periodicals archive ?
This summer, London Fire Brigade has tackled a total of 1,010 grass fires.
A South Wales Fire and Rescue Service spokeswoman said: "We are working with our communities and partner agencies to reduce deliberate grass fires, with a focus on preventative activities to ensure that we engage with key groups and keep the communities of South Wales safe.
23pm, Pontypridd crews used a hose reel to tackle another deliberate grass fire on Cilfynydd Common.
Anyone who witnessed the grass fire on Monday in Gungahlin and is yet to speak to police are urged to contact Crime Stoppers on 1800 333 000, or via the website act.
15pm, crews were called to a grass fire on Conwy mountain, which was controlled burning left unattended.
This seems like a trivial grass fire but it tied up two machines, and if there had been a house fire, crews from Newcastle, Washington or Birtley would have been sent.
A spokesman for the Northumberland Fire Brigade yesterday said: "We received reports of a grass fire just after 2.
Many were for the same incidents, including a grass fire on the Warwick bypass, and blazes at a factory, an empty house and a garage.
FIREFIGHTERS across Wales are on grass fire alert as the school holidays bring the prospect of a new round of mountain blazes to tackle.
43pm, there was a grass fire on a railway embankment off Scar Lane in Milnsbridge and another at 6pm at Farfield