Agriculture Reference
In-Depth Information
Fig. 7.6.
The time to 50% sprouting after planting on moist peat at 15°C of two
onion cultivars previously stored for 4 weeks at the temperatures shown: the
long-storing cv. 'Australian Brown' (upper) and the short-storing cv. 'Excel' (lower)
(data from Abdalla and Mann, 1963).
Fig. 7.7.
(a) The effect of storage temperature on the sprout elongation of cv.
'Excel'. (b) Leaf initiation in cv. 'Excel' stored at constant temperatures (from
Abdalla and Mann, 1963. Courtesy of
Hilgardia
).
in a study of ten cultivars including Japanese, Dutch and North American
globe types, rate of sprouting in storage was found to be slower at 5 and at 30°C
than at intermediate temperatures in all cultivars. Optimum temperatures for
sprouting ranged from 10 to 20°C, depending on cultivar (Miedema, 1994a).
A similar temperature response of sprouting was observed in cv. 'Texas Grano
1015Y', and respiration rate mirrored the response for the first 8 weeks of
storage, but at 12 weeks it increased progressively with temperature (see Fig.
7.8; Yoo
et al.
, 1997).
