The effect of potassium application on leaf water relations characteristics of field grown barley plants (Hordeum distichum L.) |
| |
Authors: | Jensen C. R. Andersen M. N. Lösch R. |
| |
Affiliation: | (1) Sect. Soil and Water and Plant Nutrition, RVAU, Copenhagen, Denmark;(2) Danish Inst. Plant and Soil Science. Res. C. Foulum, Tjele, Denmark;(3) Abt. Geobotanik, Uni. Düsseldorf, Germany |
| |
Abstract: | Leaf water relations characteristics were studied in spring barley fertilized at low (50 kg ha-1) or high (200 kg ha-1) levels of potassium applied as KCl. The leaf water relations characteristics were determined by the pressure volume (PV) technique.Seasonal analysis in fully irrigated plants showed that within 2 weeks from leaf emergence the leaf osmotic potential at full turgor (100) decreased from about –0.9 to –1.6 MPa in leaf No 7 (counting the first leaf to emerge as number one) and from about –1.1 to –1.9 MPa in leaf No 8 (the flag leaf) due to solute accumulation. 100 was 0.05 to 0.10 MPa lower in high K than in low K plants. Thus, an ontogenetically determined accumulation of solutes occurred in the leaves independent of K application. The ratio of leaf weight at full turgor to dry weight (TW/DW) decreased from about 5.5 in leaf No 6 to 4.5 in leaf No 7 and 3.8 in leaf No. 8. The TW/DW ratio was 4 to 10% higher in high K than in low K plants indicating larger leaf cell size in the former. The tissue modulus of elasticity () was increased in high K plants. The main effect of high K application on water relations was an increase in leaf water content and a slight decrease in leaf During drought limited osmotic adjustment and increase in elasticity of the leaf tissue mediated turgor maintenance. These effects were only slightly modified by high potassium application. |
| |
Keywords: | elasticity ontogenetic changes osmotic adjustment water content |
本文献已被 SpringerLink 等数据库收录! |