ISSN:
1573-5036
Keywords:
Ca efficiency
;
Lycopersicon esculentum
;
tomato
Source:
Springer Online Journal Archives 1860-2000
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
Notes:
Abstract Two lines of tomato (Lycopersicon esculentum Mill.) representing extremes in utilization effciency of absorbed Ca were studied to detect internal differences in Ca transport and distribution and factors responsible for strain differences in susceptibility to low Ca-stress. Differences in efficiency of Ca use were expressed as CaER (mg of dry weight produced for each mg of Ca absorbed by the plant). Ca-efficiency in line 113(E) appeared to be associated with a slow continuous movement of absorbed Ca, allowing for continued growth of the shoot apex and upper lamina under Ca-deficiency conditions. In the inefficient line 67(I), in contrast, Ca was rapidly deposited in the lower leaves with little upward movement in the plant after absorption. Fractionation of tissue Ca into various chemical forms suggested that Ca inefficiency also was associated with higher concentrations of insoluble Ca in the shoot tissue. The efficient line, although sustaining growth at lower levels of Ca, was capable of maintaining a higher ratio of soluble to insoluble Ca in all shoot tissues. Calcium was concentrated in the lower plant tissues of the inefficient strain, limiting its availability for continued shoot growth. Autoradiographs of lines fed45Ca during the final 8 days of a 24-day experiment suggested that upward movement was sustained in line 113(E), in spite of vastly reduced transpiration rates and a root system characterized by leakage of K ions from the roots back into the solution.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF02280180
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