Crop Science (2007) 47, 2047-2057

A.A. Reddall, L.J. Wilson, P.C. Gregg and V.O. Sadras (2007)
Photosynthetic response of cotton to spider mite damage: Interaction with light and compensatory mechanisms
Crop Science 47 (5), 2047-2057
Abstract: We investigated the photosynthetic responses of cotton (Gossypium hirsutum L.) leaves to two-spotted spider mite (Tetranychus urticae K.) damage. Light-response curves of mite-infested (+M) and uninfested (- M) leaves diverged as mite populations increased. At 17 adult female mites per leaf, photosynthetic rate of +M leaves at photosynthetic photon flux density of about 1600 µmol m^-2 s^-1 was halved from 31 µmol CO₂ m^-2 s^-1 in -M to 16 µmol CO₂ m^-2 s^-1 in +M but there was no effect on either respiration or apparent maximum quantum yield. This has important implications when comparing the response to mites of individual leaves versus canopies. In the field (i) photosynthesis declined with crop age, but the rate of decline was faster in mite-infested leaves, and (ii) mite damage progressed downward in the canopy and from basal to distal leaf positions. We found no evidence of within-leaf (i.e., basal vs. distal section) or within-plant (top vs. mid or bottom leaf) increases in photosynthesis in compensation for mite damage, except for a minor enhancement of photosynthesis in bottom leaves of mite-infested crops due to greater light penetration in canopies severely defoliated by mite damage.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Lewis J. Wilson, Peter C. Gregg

Research topic(s) for pests/diseases/weeds:
resistance/tolerance/defence of host
damage/losses/economics

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Tetranychus urticae	Cotton (Gossypium)