Spatial distributions of inorganic ions and sugars contributing to osmotic adjustment in the elongating wheat leaf under saline soil conditions

1998 ◽  
Vol 25 (5) ◽  
pp. 591 ◽  
Author(s):  
Yuncai Hu ◽  
Urs Schmidhalter
Keyword(s):  
Osmotic Adjustment ◽  
Saline Soil ◽  
Inorganic Ions ◽  
Triticum Aestivum L ◽  
Soil Conditions ◽  
Spatial Distributions ◽  
Elongation Zone ◽  
Leaf Base ◽  
Deposition Rates ◽  
Wheat Leaf

In this study, we quantified the spatial distributions of inorganic ions and sugars contributing to osmotic adjustment and their net deposition rates in the elongating and mature zones of leaf 4 of the main stem of spring wheat (Triticum aestivum L. cv. Lona) during its linear growth phase under saline soil conditions. Plants were grown in growth chambers in soil irrigated/treated with nutrient solution containing either no added or 120 mM NaCl. The sampling was conducted on the 3rd day after emergence of leaf 4 at 3 and 13 h into the 16 h photoperiod. The patterns of spatial distributions of total osmoticum, cation, anion and sugar contents (mmol kg-1 H2O) were distinct and were affected by salinity. The total osmoticum content in the region between 0 and 60 mm above the leaf base differed between the two harvests at 120 mM NaCl. Net deposition rates of total osmotica, cations, anions, and sugars (mmol kg-1 H2O h-1) in both treatments increased from the base of the leaf to the most actively elongating location and then decreased near the end of the elongation zone. Contributions of cations, anions, and sugars to osmotic adjustment varied with distance from the leaf base, and were about 21–30, 15–21, and 13%, respectively, in the elongation zone. We suggest that the accumulation of solutes under saline conditions occurs both by increasing the net deposition rate of osmotica and by reducing growth.

Spatial distributions and net deposition rates of Fe, Mn and Zn in the elongating leaves of wheat under saline soil conditions

2000 ◽  
Vol 27 (1) ◽  
pp. 53 ◽  
Author(s):  
Yuncai Hu ◽  
Sabine von Tucher ◽  
Urs Schmidhalter
Keyword(s):  
Linear Growth ◽  
Saline Soil ◽  
Leaf Growth ◽  
Distribution Patterns ◽  
Triticum Aestivum L ◽  
Soil Conditions ◽  
Spatial Distributions ◽  
Elongation Zone ◽  
Deposition Rates ◽  
Silty Loam

In this study, we quantified the spatial distributions of Fe, Mn and Zn and their net deposition rates in the elongating and mature zones of leaf 4 on the main stem of spring wheat (Triticum aestivum L.) on a millimetre scale during its linear growth phase under saline soil conditions. Plants were grown in an illitic-chloritic silty loam with 0 and 120 mМ NaCl in growth chambers. The sampling was conducted on the 3rd day after leaf 4 emerged during the photoperiod. The patterns of spatial distributions of Fe, Mn and Zn concentrations (mmol kg–1 FW) in the growing leaves were distinct. Salinity affected the distri-bution pattern of Fe concentration on the FW basis, whereas it did not affect those of the Zn and Mn. The distribution patterns of Fe and Mn differed from those for N, P, K, Ca and Mg found in a previous study, whereas the distribution pattern of Zn was similar to those of Mg, P and N. The spatial distribution of the net deposition rates (mmol kg–1 FW h–1) in both treatments demonstrated the strongest sink for the micronutrients in the elongation zone, and their net deposition rates were enhanced by 120 mМ NaCl at the middle of the elongation zone. From the results, we conclude that the inhibition of leaf growth of wheat is probably not due to the effect of salinity on Fe, Mn and Zn in leaves.

Reduced cellular cross-sectional area in the leaf elongation zone of wheat causes a decrease in dry weight deposition under saline conditions

2001 ◽  
Vol 28 (2) ◽  
pp. 165 ◽  
Author(s):  
Yuncai Hu ◽  
Urs Schmidhalter
Keyword(s):  
Spatial Distribution ◽  
Leaf Growth ◽  
Dry Weight ◽  
Triticum Aestivum L ◽  
Leaf Length ◽  
Cross Sectional Area ◽  
Elongation Zone ◽  
Sectional Area ◽  
Leaf Base ◽  
Cross Sectional

Expansion and dry weight (DW) of wheat leaves are spatially distributed along the axis and affected by salinity. The objective of this study was to evaluate the effect of salinity on the spatial distribution of cellular cross-sectional area and DW in the elongating and mature leaf zones of leaf 4 of the main stem of spring wheat (Triticum aestivum L. cv. Lona) during its linear growth phase. Plants were grown in illitic–chloritic silt loam with 0 and 120 mM NaCl in a growth chamber. Cellular cross-sectional area and DW contents of leaves were determined on the 5–20-mm scale along the leaf axis. Spatial distribution of cellular cross-sectional area changed slightly with distance within the elongation zone in both treatments. The cellular cross-sectional area of the leaf at 120 mM NaCl was reduced by 32% at 5 mm, as compared with about 36% averaged from the region between 5 and 30 mm from the leaf base, indicating that the reduction in the cellular cross-sectional area by salinity occurred mainly at the leaf base when the leaf initiates. A slight decrease in the DW per leaf length at a given location in the elongation zone may be due to the strongly decreased cellular cross-sectional area by salinity. This suggests that the limitation of leaf growth by salinity may be due mainly to the effect of salinity on leaf expansion, but not due to the effect on the synthesis of dry matter.

Carbohydrate deposition and partitioning in elongating leaves of wheat under saline soil conditions

2000 ◽  
Vol 27 (4) ◽  
pp. 363 ◽  
Author(s):  
Yuncai Hu ◽  
Hans Schnyder ◽  
Urs Schmidhalter
Keyword(s):  
Cell Wall ◽  
Secondary Cell Wall ◽  
Sucrose Concentration ◽  
Control Treatment ◽  
Elongation Zone ◽  
Leaf Elongation ◽  
Leaf Base ◽  
Deposition Rates ◽  
Deposition Zone ◽  
Cell Wall Deposition

The objective of this study was to quantitatively evaluate the effect of salinity on the spatial distributionof glucose, fructose, sucrose, fructan and total C contents, as well as on their net deposition rates in the elongation and maturation zones of leaf 4 of the main stem of spring wheat (Triticum aestivum L.) during its linear growth phase. Plants were grown in growth chambers in 1.5-L pots containing an illitic–chloritic silty loam treated with or without 120 mM NaCl. 3 d after emergence of leaf 4, sampling started at 3 and 13 h into the 16 h photoperiod. The distribution of carbohydrates along the leaf axis showed distinct patterns that were altered by salinity and time in the photoperiod. Glucose and fructose concentrations were low at the base of the elongation zone and increased sharply up to the end of the leaf elongation zone in the two treatments. In contrast, sucrose concentration in the elongation zone was high at the leaf base and decreased sharply with distance from the base up to the end of the leaf elongation zone in both treatments. The main effect of salinity on the water-soluble carbohydrates (WSC) was that it significantly increased sucrose concentration in the elongation zone throughout the day and accumulation in the photo-synthetically active zone during the photoperiod. Net deposition rates of sucrose and fructan in the elongation zone were enhanced by 120 mM NaCl. Salinity did not affect the sucrose import rate (g C kg -1 H2O h -1 ) in the sink (the elongation and secondary cell wall deposition zone). However, the partitioning of imported sucrose to WSC and structural C varied with salinity. In the basal part of the leaf (0-15 mm above the leaf base), net deposition of sucrose in the control treatment accounted for 7% of imported sucrose, compared with 17% at 120 mM NaCl. Eighty-seven percent of imported sucrose in the control treatment and 75% in the salinized treatment was used for synthesis of structural biomass (estimated as total C minus WSC-C). Conversely, in the 15–30 mm zone (i.e. in the distal part of the elongation zone and the secondary cell wall deposition zone), a greater fraction of imported sucrose was partitioned to synthesis of structural C under saline conditions. There was no significant effect of salinity on sucrose use in the region 30–60 mm.

Effect of Nano, Bio and Organic Fertilizers on Some Soil Physical Properties and Soybean Productivity in Saline Soil

2021 ◽  
pp. 44-57
Author(s):  
Kh. A. Shaban ◽  
M. A. Esmaeil ◽  
A. K. Abdel Fattah ◽  
Kh. A. Faroh
Keyword(s):  
Humic Acid ◽  
Hydraulic Conductivity ◽  
Physical Properties ◽  
Bulk Density ◽  
Saline Soil ◽  
Field Capacity ◽  
Soil Physical Properties ◽  
Organic Fertilizers ◽  
Mineral Fertilizers ◽  
Soil Conditions

A field experiment was carried out at Khaled Ibn El-waleed village, Sahl El-Hussinia, El-Sharkia Governorate, Egypt, during two summer seasons 2019 and 2020 to study the effect of NPK nanofertilizers, biofertilizers and humic acid combined with or without mineral fertilizers different at rates on some soil physical properties and soybean productivity and quality under saline soil conditions. The treatments consisted of: NPK-chitosan, NPK-Ca, humic acid, biofertilzer and control (mineral NPK only). In both seasons, the experiment was carried out in a split plot design with three replicates. The results indicated a significant increase in the soybean yield parameters as compared to control. There was also a significant increase in dry and water stable aggregates in all treatments as compared to control. The treatment NPK-Chitosan was the best in improving dry and stable aggregates. Also, hydraulic conductivity and total porosity values were significantly increased in all treatments due to increase in soil aggregation and porosity that led to increase in values of hydraulic conductivity. Values of bulk density were decreased, the lowest values of bulk density were found in NPK-chitosan treatment as a result of the high concentration of organic matter resulted from NPK-chitosan is much lighter in weight than the mineral fraction in soils. Accordingly, the increase in the organic fraction decreases the total weight and bulk density of the soil. Concerning soil moisture constants, all treatments significantly increased field capacity and available water compared to control. This increase was due to improvement of the soil aggregates and pores spaces which allowed the free movement of water within the soil thereby, increasing the moisture content at field capacity.

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