290
H. WALTER AND E. STADELMANN
TABLE X I X
D E G R E E OF SUCCULENCE (IN W A T E R CONTENT P E R U N I T A R E A L E A F SURFACE),
SALT CONTENT (IN P E R C E N T OF W A T E R CONTENT) AND W A T E R CONTENT (IN
P E R C E N T OF D R Y W E I G H T ) OF Alyssum maritimum
DURING THE M A I N
FLOWERING T I M E (A) AND 4 W E E K S LATER AT THE E N D OF THE
M A I N FLOWERING T I M E (B) IN RELATION TO THE ADDITION
OF NaCl SOLUTIONS TO THE SOIL
0
(A)
Degree of succulence
Water content
Salt content
(B)
Degree of succulence
Water content
Salt content
Amount of NaCl added to the soil (ml)
6
0
1.6
856
0.37
2.7
1360
0.31
100
1.7
913
2.00
2.8
1100
1.86
250
2.8
966
2.01
4 . 1
1515
2.18
300
3.2
1022
3.00
4.9
1508
2.50
1 After Schratz (1936, p . 184, Table 15).
Probably a 1 M NaCl solution was used (see Schratz 1935 p . 69).
The seasonal changes of the osmotic potential of soil and leaf press sap
and the contribution of NaCl were investigated for some halophytes and
glycophytes at natural habitats on the sea shore near Naples (Italy). In
all species tested NaCl contributed about 50-90% of the total osmotic potential of the cell sap (Table X X ) . The salt concentration in the soil and
in the cell sap changes seasonally. The highest uptake of NaCl into the
plants occurs in spring when plants grow fastest (Önal, 1966, p. 226).
A close relationship between the degree of succulence and the chloride
fraction of the osmotic potential of the leaf press sap was found in mangrove plants (Table XXI; see also Mishra 1967, p. 100; Mishra and Joshi
1966, pp. 27, 2 8 ) . The degree of succulence for halophytes grown in
nutrient solutions with added NaCl parallels the NaCl concentration. When
KC1 is added to the nutrient solution the degree of succulence is less than
with NaCl. Therefore, a specific action of the cations on succulence may
also be assumed (Önal, 1969b, p. 328).
Optimal NaCl concentration in the nutrient solution is for Salicornia
herbacea 1.0%, for Spergularia salina 0-0.5%, and for Suaeda maritima
and Salsola kali 0.5%. With higher NaCl concentrations fresh weight and
dry weight decrease. Depending upon the species the shoot growth is more
inhibited {Spergularia) or less inhibited {Suaeda, Salsola) than the root
H. WALTER AND E. STADELMANN
TABLE X I X
D E G R E E OF SUCCULENCE (IN W A T E R CONTENT P E R U N I T A R E A L E A F SURFACE),
SALT CONTENT (IN P E R C E N T OF W A T E R CONTENT) AND W A T E R CONTENT (IN
P E R C E N T OF D R Y W E I G H T ) OF Alyssum maritimum
DURING THE M A I N
FLOWERING T I M E (A) AND 4 W E E K S LATER AT THE E N D OF THE
M A I N FLOWERING T I M E (B) IN RELATION TO THE ADDITION
OF NaCl SOLUTIONS TO THE SOIL
0
(A)
Degree of succulence
Water content
Salt content
(B)
Degree of succulence
Water content
Salt content
Amount of NaCl added to the soil (ml)
6
0
1.6
856
0.37
2.7
1360
0.31
100
1.7
913
2.00
2.8
1100
1.86
250
2.8
966
2.01
4 . 1
1515
2.18
300
3.2
1022
3.00
4.9
1508
2.50
1 After Schratz (1936, p . 184, Table 15).
Probably a 1 M NaCl solution was used (see Schratz 1935 p . 69).
The seasonal changes of the osmotic potential of soil and leaf press sap
and the contribution of NaCl were investigated for some halophytes and
glycophytes at natural habitats on the sea shore near Naples (Italy). In
all species tested NaCl contributed about 50-90% of the total osmotic potential of the cell sap (Table X X ) . The salt concentration in the soil and
in the cell sap changes seasonally. The highest uptake of NaCl into the
plants occurs in spring when plants grow fastest (Önal, 1966, p. 226).
A close relationship between the degree of succulence and the chloride
fraction of the osmotic potential of the leaf press sap was found in mangrove plants (Table XXI; see also Mishra 1967, p. 100; Mishra and Joshi
1966, pp. 27, 2 8 ) . The degree of succulence for halophytes grown in
nutrient solutions with added NaCl parallels the NaCl concentration. When
KC1 is added to the nutrient solution the degree of succulence is less than
with NaCl. Therefore, a specific action of the cations on succulence may
also be assumed (Önal, 1969b, p. 328).
Optimal NaCl concentration in the nutrient solution is for Salicornia
herbacea 1.0%, for Spergularia salina 0-0.5%, and for Suaeda maritima
and Salsola kali 0.5%. With higher NaCl concentrations fresh weight and
dry weight decrease. Depending upon the species the shoot growth is more
inhibited {Spergularia) or less inhibited {Suaeda, Salsola) than the root