scholarly journals Can UAV-Based Infrared Thermography Be Used to Study Plant-Parasite Interactions between Mistletoe and Eucalypt Trees?

2018 ◽  
Vol 10 (12) ◽  
pp. 2062 ◽  
Author(s):  
Wouter Maes ◽  
Alfredo Huete ◽  
Michele Avino ◽  
Matthias Boer ◽  
Remy Dehaan ◽  
...  
Keyword(s):  
Infrared Thermography ◽  
Forest Inventory ◽  
Forest Type ◽  
New South ◽  
Canopy Temperature ◽  
Plant Water Relations ◽  
Plant Parasite ◽  
South Wales ◽  
Large Populations ◽  
Aerial Vehicle

Some of the remnants of the Cumberland Plain woodland, an endangered dry sclerophyllous forest type of New South Wales, Australia, host large populations of mistletoe. In this study, the extent of mistletoe infection was investigated based on a forest inventory. We found that the mistletoe infection rate was relatively high, with 69% of the Eucalyptus fibrosa and 75% of the E. moluccana trees being infected. Next, to study the potential consequences of the infection for the trees, canopy temperatures of mistletoe plants and of infected and uninfected trees were analyzed using thermal imagery acquired during 10 flights with an unmanned aerial vehicle (UAV) in two consecutive summer seasons. Throughout all flight campaigns, mistletoe canopy temperature was 0.3–2 K lower than the temperature of the eucalypt canopy it was growing in, suggesting higher transpiration rates. Differences in canopy temperature between infected eucalypt foliage and mistletoe were particularly large when incoming radiation peaked. In these conditions, eucalypt foliage from infected trees also had significantly higher canopy temperatures (and likely lower transpiration rates) compared to that of uninfected trees of the same species. The study demonstrates the potential of using UAV-based infrared thermography for studying plant-water relations of mistletoe and its hosts.

scholarly journals Morphological Exposure of Rocky Platforms: Filling the Hazard Gap Using UAVs

Drones ◽  
2019 ◽  
Vol 3 (2) ◽  
pp. 42
Author(s):  
Rafael C. Carvalho ◽  
Colin D. Woodroffe
Keyword(s):  
New South ◽  
Hazard Index ◽  
Wave Direction ◽  
Site Specific ◽  
Edge Type ◽  
South Wales ◽  
Aerial Vehicle ◽  
Seaward Edge ◽  
High Wave Energy ◽  
Study Sites

Rock platforms are dangerous environments commonly subject to high wave energy on the open coast. Platform morphology is central to understanding what makes one stretch of coastline more hazardous than another, and it can be used to create site-specific morphological exposure hazard indices to assess the relative risk of being washed into the sea, assisting coastal managers in an effort to reduce the number of injuries and drowning incidents. This paper describes the use of an unmanned aerial vehicle (UAV) to derive morphological parameters for two data-poor rock platforms along the Illawarra coast of southern New South Wales, to fill the gap using an easily replicable site-specific hazard index, developed previously, that can be applied to other microtidal wave-dominated settings. The approach is based on the subdivision of the terrestrial seaward edge of platforms into segments, classified according to mean elevation, orientation and edge type, to model different weighting scenarios of predominant southeasterly and northeasterly wave direction. UAV-derived results were deemed satisfactory for all study sites, and a comparison of results derived from LiDAR for two platforms suggested that UAV data can be successfully used to guide risk policy on rock coasts, despite differences in the delimitation of the seaward edge due to tidal level during survey acquisition.

Comparison of lucernes when grown on a heavy clay soil infected by Phytophthora, and their response to attack by the spotted alfalfa aphid (Therioaphis trifolii f. maculata)

1981 ◽  
Vol 21 (108) ◽  
pp. 63 ◽  
Author(s):  
VE Rogers
Keyword(s):  
Root Rot ◽  
Clay Soil ◽  
New South ◽  
Combined Effects ◽  
Phytophthora Root Rot ◽  
Aphid Infestation ◽  
South Wales ◽  
Heavy Clay ◽  
Large Populations ◽  
The Usa

Eighteen lucerne cultivars were sown at Deniliquin, New South Wales, in 1976. The aim of the trial was to assess these cultivars for their performance on an irrigated heavy clay soil infected by P. megasperma. The unforeseen arrival of the spotted alfalfa aphid (SAA) in December 1977 complicated the original assessment, but provided an opportunity of assessing the combined effects of SAA and P. megasperma. Twelve of the cultivars were introduced from the USA, and six were Australian lines. The American cultivars were AS1 3, AS1 3R, AS49, AS49R, WL451, WL501 R, WL508, WL512, DeKalb 167, DeKalb 185, Resistador II and Lahontan. None of these was damaged by SAA, and all except WL508 appeared to be well adapted to the heavy clay soil. The Australian cultivars Hunter River, Paravivo and Siro Peruvian were all badly affected by the aphid, and in Siro Peruvian the loss in production was accentuated by Phytophthora root rot. The Australian cultivar Falkiner and its parent line, Lahontan Cycle 4, carried large populations of aphids, but the effect on their production was only slight and temporary. Another Australian line, C3 Composite, yielded well until the aphid infestation, when its yield was temporarily reduced, but recovered after the aphids disappeared. Neither Falkiner nor C3 Composite was affected by root rot.

Ramularia ajugae. [Descriptions of Fungi and Bacteria].

2016 ◽  
Author(s):  
T. V. Andrianova
Keyword(s):  
South Africa ◽  
Host Plants ◽  
New South ◽  
Conservation Status ◽  
Bare Ground ◽  
Plant Parasite ◽  
South Wales ◽  
Mixed Plantations ◽  
Deciduous Woodland ◽  
Kirov Oblast

Abstract A description is provided for Ramularia ajugae, a plant parasite, apparently obligately associated with its host plants, causing a leafspot disease, with records on living, dying and dead leaves. This species has been recorded with its host plants from deciduous woodland, mixed plantations, bare ground in alder swamps, on rocks by stream, in parkland, on moorland, and in fens and farmlard. Some information on its associated organisms and substrata, habitats, dispersal and transmission and conservation status is given, along with details of its geographical distribution (Africa (Kenya, South Africa)), North America (USA (Massachusetts, Ohio)), Asia (Armenia, Azerbaijan, China (Guangxi), Georgia, India (Himachal Pradesh), Australasia (Australia (New South Wales, Queensland), New Zealand), Europe (Austria, Belgium, Bulgaria, Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Latvia, Lithuania, Montenegro, Netherlands, Norway, Poland, Romania, Russia (Kirov oblast, Lipetsk oblast), Serbia, Sweden, Switzerland, Ukraine, UK)) and hosts (including Ajuga spp.). No reports of negative economic impacts of this fungus have been found.

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