European Journal of Plant Pathology (1997) 103, 785-793

L. Geagea, L. Huber and I. Sache (1997)
Removal of urediniospores of brown (Puccinia recondita f.sp. tritici) and yellow (P. striiformis) rusts of wheat from infected leaves submitted to a mechanical stress
European Journal of Plant Pathology 103 (9), 785-793
Abstract: The passive spore removal from colonies due to mechanical stress was compared in the brown (Puccinia recondita f.sp. tritici) and yellow (P. striiformis) rusts of wheat. Mechanical stress was applied using either a miniaturized wind tunnel or a centrifuge. In wind-tunnel experiments, a wind of minimum velocity of 1.3 and 1.8 m s^-1 for P. recondita f.sp. tritici and P. striiformis, respectively, applied for at least 10 seconds, was necessary to remove spores. The interaction between wind velocity and cumulated duration was significant for both rusts. At low wind velocity, a longer duration was required to remove the spores than at high wind velocity, and vice versa. In centrifugation experiments, the maximum spore removal occurred for angular velocities of 10³ and 2 10³ rotations min^-1, for P. recondita f.sp. tritici and P. striiformis, respectively, applied for 5 min. Calculation of the aerodynamic and centrifugal forces showed that the forces necessary to remove spores are greater for P. striiformis than for P. recondita f.sp. tritici. This difference can be related to the size of the dispersal unit, which is larger in P. striiformis than in P. recondita f.sp. tritici due to spore clustering. These observations are consistent with the differences in the mean spore dispersal distance, which is usually smaller in P. striiformis than in P. recondita f.sp. tritici.
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Link to article at publishers website
Database assignments for author(s): Ivan Sache

Research topic(s) for pests/diseases/weeds:
general biology - morphology - evolution
transmission/dispersal of plant diseases

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Puccinia striiformis	Wheat (Triticum)
	Puccinia triticina	Wheat (Triticum)