Commercial citrus growers are often challenged by environmental conditions in winter, including low seasonal rainfall that is typical in many citrus growing regions.
Growers must rely on irrigation to sustain citrus crops through dry winters, so understanding how to determine citrus irrigation needs is critical for successful operations.
Authors of a study published in HortScience noted that current methods used to determine moisture needs for citrus are limited, in that they do not account for effects of cold acclimation on water requirements.
"Evidence suggests that at least some changes in plant water deficits occur as a result of cold temperatures and not dry soil," noted Robert Ebel, lead author of the study. "Changes in citrus water relations during cold acclimation and independent of soil moisture content are not well understood. Our study was conducted to characterize changes in plant relations of citrus plants with soil moisture carefully maintained at high levels to minimize drought stress."
Ebel and his colleagues conducted two experiments--the first in Immokalee, Florida, using potted sweet orange, and the second in Auburn, Alabama, using Satsuma mandarin trees. The citrus plants were exposed to progressively lower, non-freezing temperatures for 9 weeks. During the experiments trees were watered twice daily--three times on the days data were collected--to minimize drought stress.
Results of the experiments showed that soil moisture was higher for plants in the cold compared to plants in the warm chamber, and results showed that cold temperatures promoted stomatal closure, higher root resistance, lower stem water potential, lower transpiration, and lower stem water potential. Leaf relative water content was not different for cold-acclimated trees compared with the control trees. The key to minimizing drought stress, the scientists found, was carefully maintaining high soil moisture contents throughout the experiments, especially on the days that the measurements were performed.
"Our modern understanding of plant water relations has mainly evolved from studying growing plants at warm temperatures and in soils of varying moisture contents," Ebel explained. "However, this study demonstrates that those relationships are not consistent for citrus trees exposed to cold-acclimating temperatures."
The authors added that the study findings could have implications for commercial citrus growers who currently use traditional measures of determining irrigation scheduling during winter months.
The complete study and abstract are available on the ASHS HortScience electronic journal web site: http://hortsci.ashspublications.org/content/48/10/1309.abstract
Founded in 1903, the American Society for Horticultural Science (ASHS) is the largest organization dedicated to advancing all facets of horticultural research, education, and application.
Mike W. Neff | EurekAlert!
Six-legged livestock -- sustainable food production
11.05.2017 | Faculty of Science - University of Copenhagen
Elephant Herpes: Super-Shedders Endanger Young Animals
04.05.2017 | Universität Zürich
The world's highest gain high power laser amplifier - by many orders of magnitude - has been developed in research led at the University of Strathclyde.
The researchers demonstrated the feasibility of using plasma to amplify short laser pulses of picojoule-level energy up to 100 millijoules, which is a 'gain'...
Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.
Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....
Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.
The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....
An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.
We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...
Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.
Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...
24.05.2017 | Event News
23.05.2017 | Event News
22.05.2017 | Event News
29.05.2017 | Earth Sciences
29.05.2017 | Life Sciences
29.05.2017 | Physics and Astronomy