The Experts below are selected from a list of 318 Experts worldwide ranked by ideXlab platform
Christopher J. Atkinson - One of the best experts on this subject based on the ideXlab platform.
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Application of deficit Irrigation to container-grown hardy ornamental nursery stock via Overhead Irrigation, compared to drip Irrigation
Agricultural Water Management, 2015Co-Authors: Michael J. Davies, Christopher J. Atkinson, Richard Harrison-murray, Olga M. GrantAbstract:Growth control of container-grown hardy nursery stock generally requires substantial labour investment. Therefore the possibility of alternative growth control using deficit Irrigation is appealing. Increasing water costs and limited availability of abstraction licences have added further incentives for nursery stock producers to use deficit Irrigation. There are still, however, concerns that inherent non-uniformity of water uptake under commonly used Overhead Irrigation, and differing Irrigation requirements of diverse crops and substrates, may limit the commercial relevance of a protocol developed for single crops growing in 100% peat and irrigated with a high precision drip system. The aim of this research was to determine whether growth control of hardy nursery stock is possible using deficit Irrigation applied with conventional Overhead Irrigation. Over two years, crop growth under an Overhead Irrigation system was compared under full Irrigation and two severities of deficit Irrigation. Initially, two crops of contrasting canopy structure i.e. Cornus alba and Lonicera periclymenum were grown. In a subsequent experiment one crop (Forsythia×intermedia) was grown in two substrates with contrasting quantities of peat (60 and 100%). Deficit Irrigation was found to be highly effective in controlling vegetative growth when applied using Overhead Irrigation—with similar results as when drip Irrigation was used. This comparable response suggests that deficit Irrigation can be applied without precision drip Irrigation. Scheduling two very different crops with respect to their water use and uptake potential, however, highlighted challenges with respect to application of appropriate deficits for very different crops under one system; responses to deficit Irrigation will be more consistent where nursery management allows for scheduling of crops with very different architecture and water use under different regimes. The effectiveness of deficit Irrigation in controlling the growth of Forsythia was similar when a reduced peat based substrate was compared with pure peat; additionally, flowering was enhanced.
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Irrigation scheduling and Irrigation systems optimising Irrigation efficiency for container ornamental shrubs
Irrigation Science, 2009Co-Authors: Olga M. Grant, Michael J. Davies, Helen Longbottom, Christopher J. AtkinsonAbstract:Water use and plant growth and quality were compared across different nursery stock beds, different methods of applying Irrigation, and different methods of scheduling Irrigation. With Overhead Irrigation, scheduling of Irrigation according to plant demand, along with an Irrigation system designed to maximise Irrigation uniformity, resulted in substantial water savings, without reducing plant quality. This was the case in both wet and dry years. In the dry year, plant quality was particularly good when grown on a sub-irrigated sand bed; this system also used less water than any of the Overhead Irrigation systems. Two different systems were effective in scheduling Overhead Irrigation, one based on the volumetric moisture in the growing substrate, and the other based on plant evapotranspiration. The latter was determined with a small sensor with wet and dry artificial “leaves”, the output of which correlated with that obtained following the Penman–Monteith method based on a full set of meteorological data.
Olga M. Grant - One of the best experts on this subject based on the ideXlab platform.
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Application of deficit Irrigation to container-grown hardy ornamental nursery stock via Overhead Irrigation, compared to drip Irrigation
Agricultural Water Management, 2015Co-Authors: Michael J. Davies, Christopher J. Atkinson, Richard Harrison-murray, Olga M. GrantAbstract:Growth control of container-grown hardy nursery stock generally requires substantial labour investment. Therefore the possibility of alternative growth control using deficit Irrigation is appealing. Increasing water costs and limited availability of abstraction licences have added further incentives for nursery stock producers to use deficit Irrigation. There are still, however, concerns that inherent non-uniformity of water uptake under commonly used Overhead Irrigation, and differing Irrigation requirements of diverse crops and substrates, may limit the commercial relevance of a protocol developed for single crops growing in 100% peat and irrigated with a high precision drip system. The aim of this research was to determine whether growth control of hardy nursery stock is possible using deficit Irrigation applied with conventional Overhead Irrigation. Over two years, crop growth under an Overhead Irrigation system was compared under full Irrigation and two severities of deficit Irrigation. Initially, two crops of contrasting canopy structure i.e. Cornus alba and Lonicera periclymenum were grown. In a subsequent experiment one crop (Forsythia×intermedia) was grown in two substrates with contrasting quantities of peat (60 and 100%). Deficit Irrigation was found to be highly effective in controlling vegetative growth when applied using Overhead Irrigation—with similar results as when drip Irrigation was used. This comparable response suggests that deficit Irrigation can be applied without precision drip Irrigation. Scheduling two very different crops with respect to their water use and uptake potential, however, highlighted challenges with respect to application of appropriate deficits for very different crops under one system; responses to deficit Irrigation will be more consistent where nursery management allows for scheduling of crops with very different architecture and water use under different regimes. The effectiveness of deficit Irrigation in controlling the growth of Forsythia was similar when a reduced peat based substrate was compared with pure peat; additionally, flowering was enhanced.
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Irrigation scheduling and Irrigation systems optimising Irrigation efficiency for container ornamental shrubs
Irrigation Science, 2009Co-Authors: Olga M. Grant, Michael J. Davies, Helen Longbottom, Christopher J. AtkinsonAbstract:Water use and plant growth and quality were compared across different nursery stock beds, different methods of applying Irrigation, and different methods of scheduling Irrigation. With Overhead Irrigation, scheduling of Irrigation according to plant demand, along with an Irrigation system designed to maximise Irrigation uniformity, resulted in substantial water savings, without reducing plant quality. This was the case in both wet and dry years. In the dry year, plant quality was particularly good when grown on a sub-irrigated sand bed; this system also used less water than any of the Overhead Irrigation systems. Two different systems were effective in scheduling Overhead Irrigation, one based on the volumetric moisture in the growing substrate, and the other based on plant evapotranspiration. The latter was determined with a small sensor with wet and dry artificial “leaves”, the output of which correlated with that obtained following the Penman–Monteith method based on a full set of meteorological data.
Peter M. Kopittke - One of the best experts on this subject based on the ideXlab platform.
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Overhead-Irrigation with saline and alkaline water: deleterious effects on foliage of Rhodes grass and leucaena
Agricultural Water Management, 2016Co-Authors: Federico D.f. Cicchelli, Neal W. Menzies, J. Bernhard Wehr, Scott A. Dalzell, Peter M. KopittkeAbstract:Abstract Saline and alkaline water represents a potentially valuable resource provided its Irrigation does not decrease plant growth. Although the adverse effects of salts within the rooting environment are well-studied, comparatively little is known regarding the direct effects of Overhead-Irrigation of saline and alkaline water on plant foliage. The present study examined the potential deleterious effects of saline (electrical conductivity, EC, ≤15 dS m−1) and alkaline (≤2000 mg L−1, CaCO3 equivalent) water on foliage of Rhodes grass (Chloris gayana cv. Reclaimer) and leucaena (Leucaena leucocephala ssp. glabrata cv. Tarramba) under a range of growing-conditions. Foliage of leucaena was sensitive, with necrosis and chlorosis evident for saline water at an EC ≥3 dS m−1 and alkaline water containing ≥500 mg L−1 (CaCO3 equivalent). For leucaena, this damage to the foliage reduced relative shoot fresh mass and chlorophyll fluorescence for saline-treatments, but alkalinity did not reduce relative shoot fresh mass or chlorophyll fluorescence in any treatment. In contrast to leucaena, relative shoot fresh mass of Rhodes grass was not reduced by foliar-applied salinity in any treatment (nor did alkalinity reduce growth of Rhodes grass). It was noted that growing conditions influenced the magnitude of the deleterious effects, with salinization of the soil slightly increasing tolerance to foliar-applied saline water for leucaena. This study has demonstrated that whilst saline and alkaline water can potentially be used for Overhead Irrigation, differences in observed tolerance exist between plant species, and are influenced by growing conditions.
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An assessment of the potential impacts of the Overhead Irrigation of saline and alkaline water on plant foliage. Santos Ltd.
2014Co-Authors: Johannes B. Wehr, Neal W. Menzies, Michiel Steenhauer, Peter M. KopittkeAbstract:Overhead Irrigation of plants with unamended CS-water may have an effect on the foliage of pasture plant species. This study investigated the effect of CS water (6 dS/m) and diluted to 3.2 dS/m and 4.6 dS/m on the foliage of lucerne, leucaena and Rhodes grass. These waters were Overhead-irrigated a total of 15 times across a five week period. Rhodes grass was the most tolerant species examined. Upon completion of the experiment, the plants were generally healthy and even 75% CS-water did not appear to stress the foliage when assessed using visual symptoms, chlorophyll fluorescence, or shoot biomass. Lucerne was more sensitive to Overhead Irrigation with CS-water, and even though shoot biomass wasn’t significantly reduced in any treatment.
Michael J. Davies - One of the best experts on this subject based on the ideXlab platform.
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Application of deficit Irrigation to container-grown hardy ornamental nursery stock via Overhead Irrigation, compared to drip Irrigation
Agricultural Water Management, 2015Co-Authors: Michael J. Davies, Christopher J. Atkinson, Richard Harrison-murray, Olga M. GrantAbstract:Growth control of container-grown hardy nursery stock generally requires substantial labour investment. Therefore the possibility of alternative growth control using deficit Irrigation is appealing. Increasing water costs and limited availability of abstraction licences have added further incentives for nursery stock producers to use deficit Irrigation. There are still, however, concerns that inherent non-uniformity of water uptake under commonly used Overhead Irrigation, and differing Irrigation requirements of diverse crops and substrates, may limit the commercial relevance of a protocol developed for single crops growing in 100% peat and irrigated with a high precision drip system. The aim of this research was to determine whether growth control of hardy nursery stock is possible using deficit Irrigation applied with conventional Overhead Irrigation. Over two years, crop growth under an Overhead Irrigation system was compared under full Irrigation and two severities of deficit Irrigation. Initially, two crops of contrasting canopy structure i.e. Cornus alba and Lonicera periclymenum were grown. In a subsequent experiment one crop (Forsythia×intermedia) was grown in two substrates with contrasting quantities of peat (60 and 100%). Deficit Irrigation was found to be highly effective in controlling vegetative growth when applied using Overhead Irrigation—with similar results as when drip Irrigation was used. This comparable response suggests that deficit Irrigation can be applied without precision drip Irrigation. Scheduling two very different crops with respect to their water use and uptake potential, however, highlighted challenges with respect to application of appropriate deficits for very different crops under one system; responses to deficit Irrigation will be more consistent where nursery management allows for scheduling of crops with very different architecture and water use under different regimes. The effectiveness of deficit Irrigation in controlling the growth of Forsythia was similar when a reduced peat based substrate was compared with pure peat; additionally, flowering was enhanced.
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Irrigation scheduling and Irrigation systems optimising Irrigation efficiency for container ornamental shrubs
Irrigation Science, 2009Co-Authors: Olga M. Grant, Michael J. Davies, Helen Longbottom, Christopher J. AtkinsonAbstract:Water use and plant growth and quality were compared across different nursery stock beds, different methods of applying Irrigation, and different methods of scheduling Irrigation. With Overhead Irrigation, scheduling of Irrigation according to plant demand, along with an Irrigation system designed to maximise Irrigation uniformity, resulted in substantial water savings, without reducing plant quality. This was the case in both wet and dry years. In the dry year, plant quality was particularly good when grown on a sub-irrigated sand bed; this system also used less water than any of the Overhead Irrigation systems. Two different systems were effective in scheduling Overhead Irrigation, one based on the volumetric moisture in the growing substrate, and the other based on plant evapotranspiration. The latter was determined with a small sensor with wet and dry artificial “leaves”, the output of which correlated with that obtained following the Penman–Monteith method based on a full set of meteorological data.
Federico D.f. Cicchelli - One of the best experts on this subject based on the ideXlab platform.
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Overhead-Irrigation with saline and alkaline water: deleterious effects on foliage of Rhodes grass and leucaena
Agricultural Water Management, 2016Co-Authors: Federico D.f. Cicchelli, Neal W. Menzies, J. Bernhard Wehr, Scott A. Dalzell, Peter M. KopittkeAbstract:Abstract Saline and alkaline water represents a potentially valuable resource provided its Irrigation does not decrease plant growth. Although the adverse effects of salts within the rooting environment are well-studied, comparatively little is known regarding the direct effects of Overhead-Irrigation of saline and alkaline water on plant foliage. The present study examined the potential deleterious effects of saline (electrical conductivity, EC, ≤15 dS m−1) and alkaline (≤2000 mg L−1, CaCO3 equivalent) water on foliage of Rhodes grass (Chloris gayana cv. Reclaimer) and leucaena (Leucaena leucocephala ssp. glabrata cv. Tarramba) under a range of growing-conditions. Foliage of leucaena was sensitive, with necrosis and chlorosis evident for saline water at an EC ≥3 dS m−1 and alkaline water containing ≥500 mg L−1 (CaCO3 equivalent). For leucaena, this damage to the foliage reduced relative shoot fresh mass and chlorophyll fluorescence for saline-treatments, but alkalinity did not reduce relative shoot fresh mass or chlorophyll fluorescence in any treatment. In contrast to leucaena, relative shoot fresh mass of Rhodes grass was not reduced by foliar-applied salinity in any treatment (nor did alkalinity reduce growth of Rhodes grass). It was noted that growing conditions influenced the magnitude of the deleterious effects, with salinization of the soil slightly increasing tolerance to foliar-applied saline water for leucaena. This study has demonstrated that whilst saline and alkaline water can potentially be used for Overhead Irrigation, differences in observed tolerance exist between plant species, and are influenced by growing conditions.
