ISSN:
1573-5036
Keywords:
crop carbon budget
;
grain filling
;
root respiration
;
soil respiration
;
sunflower
;
temperature response
;
water-stress
Source:
Springer Online Journal Archives 1860-2000
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
Notes:
Abstract Instantaneous rates of (soil + root) respiration were measured periodically during grain filling in sunflower crops that were i) irrigated at weekly intervals and ii) subjected to water stress for the last 25 days of the 40-day grain filling period. Daily (soil + root) respiration was calculated using instantaneous respiration rates, an empirically determined temperature response function, and diurnal records of soil temperature. Daily soil respiration was estimated using empirically determined functions linking soil respiration to soil temperature and water content. Between anthesis and maturity, daily root respiration of the irrigated crop dropped by about one half from ca. 1.8 g C m-2 d-1, exhibiting a strong association with daily crop gross photosynthesis. Water stress brought about a rapid decrease in root respiration, which fell to about 0.1 g C m-2 d-1 at maturity. Root respiration during grain filling was 46 and 30 g C m-2 for irrigated and stressed crops, respectively.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00013097
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