ISSN:
1573-5060
Keywords:
barley
;
cer
;
β-diketone
;
glaucous
;
pre-harvest sprouting
;
waxes
;
wheat
Source:
Springer Online Journal Archives 1860-2000
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
Notes:
Abstract Morphological features of the cereal ear, including awns, alter pre-harvest sprouting damage by changing the rate of water absorption during rainfall. In this paper, the potential for wheat (Triticum sp.) arid barley (Hordeum vulgare L.) waxes to reduce sprouting by increasing water repellency of the mature ear has been examined. Six barley F2 populations segregating for different non-glaucous single-gene mutants controlling waxes on ears were examined. Water repellency was assessed by measuring both the contact angle of a water drop placed on the lemma surface (internal angle) and by repetitive weighings of whole ears during their exposure to simulated rainfall. The lemma of glaucous (wild type) lines had larger water drop contact angles, an indication of poorer spread of water over the surface. In simulated rainfall, ears of the glaucous lines showed a clear reduction of wetting (20–30% less) and, after 72 h of wetting, their in-ear sprouting was reduced by 50 to 65%. When pre-wet, the glaucous ears also shed water more readily when shaken to simulate the combined effect of wind and rainfall. To reduce pre-harvest sprouting of barley it may be possible to screen visually for ears that are more glaucous but a more specific screen would be to select for lemma water drop contact angle since it is a good indicator of ear wettability and so allows differences in surface properties to be assessed. For bread wheat (T. aestivumL.), as for barley, the more glaucous the ear, the greater the water drop contact angle and the more tubular surface wax coverage seen in scanning electron microscope images. In addition, surface wax amount apparently affected in-ear wettingin lines of durum wheat, (T. turgidum L.). Possible genetic relationships between waxy/waxless genes in wheat and barley are suggested with the aim, ultimately, of altering ear glaucousness to give increased water repellency and a reduction of in-ear sprouting of wheat.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1003832031695
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