Response of wheat growth and CO2 assimilation to altering root-zone temperature

1990 ◽  
Vol 68 (12) ◽  
pp. 2698-2702 ◽  
Author(s):  
S. H. Al-Hamdani ◽  
G. W. Todd ◽  
D. A. Francko
Keyword(s):  
Water Use Efficiency ◽  
Water Potential ◽  
Water Use ◽  
Root Zone ◽  
Soluble Sugar ◽  
Leaf Conductance ◽  
Assimilation Rate ◽  
Root Zone Temperature ◽  
Use Efficiency ◽  
Zone Temperature

Wheat plants (Triticum aestivum L. var. Chisholm) grown at an air temperature of 23 °C and a root-zone temperature of 3 °C exhibited a significant reduction in shoot and root dry weight and leaf area compared with plants grown at a root-zone temperature of 23 °C. This reduction was correlated with a significantly lower CO2 assimilation rate that was associated with lower leaf conductance, lower internal CO2 concentration, and more negative water potential. Low CO2 assimilation rate was also associated with high starch and total soluble sugar levels in the shoot, less translocation of photosynthate, and possibly less sink demand. Leaf chlorophyll concentration was not affected by altering the root-zone temperature, whereas water use efficiency of plants grown at a root-zone temperature of 3 °C was as much as 1.5 times higher as those grown at 23 °C. Key words: carbohydrate, chlorophyll, photosynthate partitioning, leaf conductance, water potential, water use efficiency.

Effects of root zone temperature on root initiation and elongation in red pine seedlings

1986 ◽  
Vol 16 (4) ◽  
pp. 696-700 ◽  
Author(s):  
Chris P. Andersen ◽  
Edward I. Sucoff ◽  
Robert K. Dixon
Keyword(s):  
Root Elongation ◽  
Root Zone ◽  
Soluble Sugar ◽  
Soluble Sugars ◽  
Red Pine ◽  
Root Tip ◽  
Root Initiation ◽  
Root Zone Temperature ◽  
Pine Seedlings ◽  
Zone Temperature

The influence of root zone temperature on root initiation, root elongation, and soluble sugars in roots and shoots was investigated in a glasshouse using 2-0 red pine (Pinusresinosa Ait.) seedlings lifted from a northern Minnesota nursery. Seedlings were potted in a sandy loam soil and grown in chambers where root systems were maintained at 8, 12, 16, or 20 °C for 27 days; seedling shoots were exposed to ambient glasshouse conditions. Total new root length was positively correlated with soil temperature 14, 20, and 27 days after planting, with significantly more new root growth at 20 °C than at other temperatures. The greatest number of new roots occurred at 16 °C; the least, at 8 °C. Total soluble sugar concentrations in stem tissue decreased slightly as root temperature increased. Sugar concentrations in roots were similar at all temperatures. The results suggest that root elongation is suppressed more than root tip formation when red pine seedlings are exposed to the cool soil temperatures typically found during spring and fall outplanting.

Water use efficiency and fruit quality of table grape under alternate partial root-zone drip irrigation

2008 ◽  
Vol 95 (6) ◽  
pp. 659-668 ◽  
Author(s):  
Taisheng Du ◽  
Shaozhong Kang ◽  
Jianhua Zhang ◽  
Fusheng Li ◽  
Boyuan Yan
Keyword(s):  
Water Use Efficiency ◽  
Water Use ◽  
Fruit Quality ◽  
Drip Irrigation ◽  
Root Zone ◽  
Table Grape ◽  
Use Efficiency

Effect of New Irrigation Technology on the Physiology and Water Use Efficiency of Potato by Reclaimed Water Irrigation

2013 ◽  
Vol 726-731 ◽  
pp. 3035-3039 ◽  
Author(s):  
Xue Bin Qi ◽  
Zong Dong Huang ◽  
Dong Mei Qiao ◽  
Ping Li ◽  
Zhi Juan Zhao ◽  
...  
Keyword(s):  
Water Use Efficiency ◽  
Water Use ◽  
Drip Irrigation ◽  
Field Experiments ◽  
Root Zone ◽  
Subsurface Drip Irrigation ◽  
Treated Wastewater ◽  
Root Weight ◽  
Use Efficiency ◽  
Subsurface Drip

Agriculture is a big consumer of fresh water in competition with other sectors of the society. The agricultural sector continues to have a negative impact on the ecological status of the environment. The worlds interest in high quality food is increasing. Field experiments were conducted to investigate the effect of subsurface drip irrigation on physiological responses, yield and water use efficiency, Soil nitrogen, Root weight density of potato in the semi-humid region of middle China using subsurface drip irrigation. The experiment used second-stage treated wastewater with and without addition of chloride, and both subsurface drip and furrow irrigations were investigated. Results indicated that the alternate partial root-zone irrigation is a practicable water-saving strategy for potato. The drip with chlorinated and non-chlorinated water improved water use efficiency by 21.48% and 39.1%, respectively, and 44.1% in the furrow irrigation. Partial root zone drying irrigation stimulates potato root growth and enhances root density. The content of the heavy metal in the potato tubers is no more than the National Food Requirements, and it is consistent with National Food Hygiene Stands.

Partial root-zone drying in field-grown papaya: Gas exchange, yield, and water use efficiency

2021 ◽  
Vol 243 ◽  
pp. 106421
Author(s):  
Dionei Lima Santos ◽  
Eugênio Ferreira Coelho ◽  
Fernando França da Cunha ◽  
Sérgio Luiz Rodrigues Donato ◽  
Wallace de Paula Bernado ◽  
...  
Keyword(s):  
Gas Exchange ◽  
Water Use Efficiency ◽  
Water Use ◽  
Root Zone ◽  
Use Efficiency

Water use efficiency and water use of Mediterranean annual pastures in southern Australia

1999 ◽  
Vol 50 (6) ◽  
pp. 1035 ◽  
Author(s):  
T. P. Bolger ◽  
N. C. Turner
Keyword(s):  
Water Use Efficiency ◽  
Linear Relationship ◽  
Water Use ◽  
Management Practices ◽  
Root Zone ◽  
Annual Rainfall ◽  
High Input ◽  
Deep Drainage ◽  
Pasture Production ◽  
Use Efficiency

There is a perception in the farming and research communities that annual pastures have low produc- tivity and water use, and contribute disproportionately to problems of rising watertables and dryland salinity. Our aim was to determine potential pasture production in relation to water use and the influence of management factors on this relationship. Experiments were initiated at 4 locations along a gradient of 300–1100 mm annual rainfall across the Western Australian agricultural zone. At each site a high input treatment was compared with a low input control. There was a strong linear relationship between water use and pasture production up to 440 mm of growing- season water use. After 30 mm of water use the potential pasture production was 30 kg/ha.mm. An upper limit to pasture production may be reached at about 12 000 kg/ha in this environment due to rainfall distribution patterns and soil water holding capacity in the root-zone. Although pasture production was increased by as much as 3500 kg/ha, water use was generally similar or only slightly more for high input compared with control plots. The marginally higher water use by the high input pastures resulted in an extra 18 mm of water extracted from the subsoil at one location by the end of the third season. A drier subsoil may provide a buffer for storing excess rainfall and reduce deep drainage. Estimated drainage was small at low rainfall sites so even marginal increases in water use by highly productive annual pastures could play a significant role in reducing water loss to deep drainage and mitigating water-table rise and secondary salinisation in low rainfall regions. Management practices aimed at promoting early growth and adequate leaf area should maximise water use, water use efficiency, and yield. The linear relationship defining potential pasture production provides a useful benchmark to farmers.

Diurnal Time Course of Leaf Gas Exchange Rates and Related Characters in Drought-Acclimated and Irrigated Trifolium Subterraneum.

1995 ◽  
Vol 22 (3) ◽  
pp. 461 ◽  
Author(s):  
J Vadell ◽  
C Cabot ◽  
H Medrano
Keyword(s):  
Gas Exchange ◽  
Exchange Rates ◽  
Water Use Efficiency ◽  
Water Use ◽  
Leaf Gas Exchange ◽  
Trifolium Subterraneum ◽  
Co2 Assimilation ◽  
Carbon Gain ◽  
Assimilation Rate ◽  
Use Efficiency

The effects of drought acclimation on the diurnal time courses of photosynthesis and related characters were studied in Trifolium subterraneum L. leaves during two consecutive late spring days. Leaf CO2 assimilation rate and transpiration rate followed irradiance variations in irrigated plants. Under drought, a bimodal pattern of leaf CO2 assimilation rate developed although stomatal conductance remained uniform and low. Instantaneous water-use efficiency was much higher in droughted plants during the early morning and late evening, while during the middle of the day it was close to the value of irrigated plants. Net carbon gain in plants under drought reached 40% of the carbon gain in irrigated plants with a significant saving of water (80%). Average data derived from midday values of leaf CO2 assimilation rates and instantaneous water-use efficiency did not provide good estimates of the daily carbon gain and water-use efficiency for droughted leaves. Coupled with the morphological changes as a result of acclimation to progressive drought, modifications of diurnal patterns of leaf gas exchange rates effectively contribute to a sustained carbon gain during drought. These modifications significantly improve water-use efficiency, mainly by enabling the plant to take advantage of morning and evening hours with high air humidity.

Sign in / Sign up

Export Citation Format

Share Document