scholarly journals Spectral differentiation of oak wilt from foliar fungal disease and drought is correlated with physiological changes

2020 ◽  
Vol 40 (3) ◽  
pp. 377-390 ◽  
Author(s):  
Beth Fallon ◽  
Anna Yang ◽  
Cathleen Lapadat ◽  
Isabella Armour ◽  
Jennifer Juzwik ◽  
...  
Keyword(s):  
Water Status ◽  
Hyperspectral Data ◽  
Oak Wilt ◽  
Quercus Macrocarpa ◽  
Stress Symptoms ◽  
Spectral Models ◽  
Bur Oak ◽  
Quercus Ellipsoidalis ◽  
Sources Of Infection ◽  
Tree Stress

Abstract Hyperspectral reflectance tools have been used to detect multiple pathogens in agricultural settings and single sources of infection or broad declines in forest stands. However, differentiation of any one disease from other sources of tree stress is integral for stand and landscape-level applications in mixed species systems. We tested the ability of spectral models to differentiate oak wilt, a fatal disease in oaks caused by Bretziella fagacearum ``Bretz'', from among other mechanisms of decline. We subjected greenhouse-grown oak seedlings (Quercus ellipsoidalis ``E.J. Hill'' and Quercus macrocarpa ``Michx.'') to chronic drought or inoculation with the oak wilt fungus or bur oak blight fungus (Tubakia iowensis ``T.C. Harr. & D. McNew''). We measured leaf and canopy spectroscopic reflectance (400–2400 nm) and instantaneous photosynthetic and stomatal conductance rates, then used partial least-squares discriminant analysis to predict treatment from hyperspectral data. We detected oak wilt before symptom appearance, and classified the disease with high accuracy in symptomatic leaves. Classification accuracy from spectra increased with declines in photosynthetic function in oak wilt-inoculated plants. Wavelengths diagnostic of oak wilt were only found in non-visible spectral regions and are associated with water status, non-structural carbohydrates and photosynthetic mechanisms. We show that hyperspectral models can differentiate oak wilt from other causes of tree decline and that detection is correlated with biological mechanisms of oak wilt infection and disease progression. We also show that within the canopy, symptom heterogeneity can reduce detection, but that symptomatic leaves and tree canopies are suitable for highly accurate diagnosis. Remote application of hyperspectral tools can be used for specific detection of disease across a multi-species forest stand exhibiting multiple stress symptoms.

Absorption, Translocation, and Degradation of Tebuthiuron and Hexazinone in Woody Species

Weed Science ◽  
1984 ◽  
Vol 32 (6) ◽  
pp. 739-743 ◽  
Author(s):  
Wayne K. McNeil ◽  
Jimmy F. Stritzke ◽  
Eddie Basler
Keyword(s):  
Pinus Taeda ◽  
Loblolly Pine ◽  
Woody Species ◽  
Black Walnut ◽  
The Other ◽  
Juniperus Virginiana ◽  
Eastern Redcedar ◽  
Quercus Macrocarpa ◽  
Root Absorption ◽  
Bur Oak

Seedlings of winged elm (Ulmus dataMichx.), bur oak (Quercus macrocarpaMichx.), black walnut (Juglans nigraL.), eastern redcedar (Juniperus virginianaL.), and loblolly pine (Pinus taedaL.) were treated in nutrient solution with ring-labeled14C-tebuthiuron {N-[5-(1,1-dimethylethyl)-1,3,4-thiadiazol-2-yl]-N,N′-dimethylurea} or14C-hexazinone [3-cyclohexyl-6-(dimethylamino)-1-methyl-1,3,5-triazine-2,4(1H,3H)-dione]. Four hours later,14C was detected in all sections of winged elm treated with14C-tebuthiuron and14C-hexazinone. Root absorption of the tebuthiuron label by the other species occurred in the order: loblolly pine > bur oak > black walnut = eastern redcedar. The sequence of14C-hexazinone absorption was: loblolly pine > black walnut ≥ bur oak = eastern redcedar. Foliar accumulation of the tebuthiuron label occurred in the order: bur oak > loblolly pine > eastern redcedar = black walnut, whereas the sequence with hexazinone was loblolly pine > bur oak > black walnut = eastern redcedar. The presence of the three metabolites of hexazinone in loblolly pine suggests that it may be resistant to hexazinone as a result of its ability to degrade hexazinone rather than its ability to limit uptake.

A Description of the Previously Unknown Male of Cyrtolobus griseus Van Duzee

1951 ◽  
Vol 83 (4) ◽  
pp. 106-106
Author(s):  
Clifford J. Dennis
Keyword(s):  
Quercus Macrocarpa ◽  
University Of Wisconsin ◽  
Bur Oak ◽  
The University ◽  
Unknown Male

Apparently, the male of Cyrtolobus griseus Van Duzee (Stud. N.A. Memb. 90.16, 1908) has never been described. The following is a description of a male which is here designated the allotype. This specimen was collected in the University of Wisconsin Arboretum, Madison, July 21, 1950 from bur oak (Quercus macrocarpa Michx.). The allotype is in the author's collection.

The association of two invasive shrubs, common buckthorn (Rhamnus cathartica) and Tartarian honeysuckle (Lonicera tatarica), with oak communities in the midwestern United States

2011 ◽  
Vol 41 (10) ◽  
pp. 1981-1992 ◽  
Author(s):  
Lisa A. Schulte ◽  
Erik C. Mottl ◽  
Brian J. Palik
Keyword(s):  
United States ◽  
Soil Nutrient ◽  
Oak Forests ◽  
Quercus Alba ◽  
Forest Edges ◽  
Rhamnus Cathartica ◽  
White Oak ◽  
Midwestern United States ◽  
Quercus Macrocarpa ◽  
Bur Oak

Oak forests throughout North America are declining due to changes in disturbance regimes that have led to increased competition from other tree and shrub species. We evaluated associations between oak regeneration, the occurrence of two common invasive shrubs (common buckthorn ( Rhamnus cathartica L.) and Tartarian honeysuckle ( Lonicera tatarica L.)), and forest edges in oak forests in a portion of the midwestern United States where bur ( Quercus macrocarpa Michx.), red ( Quercus rubra L.), and white oak ( Quercus alba L.) were historically dominant. We found poor recruitment of oaks in comparison to other, more shade-tolerant tree species. Results further revealed a strong stand-scale association between bur oak, open canopy conditions, high soil nutrient levels, and the presence of common buckthorn and Tartarian honeysuckle; these same site characteristics were disassociated with red and white oak. Within red and white oak stands, however, the presence of the invasive shrubs was more pronounced near forest edges. While oak recruitment is hampered throughout stands, our research suggests that predominant constraints may vary based on soil and light gradients found along forest edges.

Retrieval of Water Use Efficiency Using Hyperspectral Indices: An Application for Tamarix ramosissima

2012 ◽  
Vol 500 ◽  
pp. 149-154
Author(s):  
Shan Shan Wang ◽  
Xi Chen ◽  
Quan Wang ◽  
An Ming Bao
Keyword(s):  
Water Status ◽  
Field Measurements ◽  
Hyperspectral Data ◽  
Plant Water Status ◽  
Tamarix Ramosissima ◽  
Sensitivity Index ◽  
Plant Water ◽  
Arid Ecosystem ◽  
Desert Shrubs ◽  
Wide Range

Many fundamental ecosystem properties and dynamics are monitored by plant water status, particularly in arid ecosystem where water is usually limiting. Although plant water status have been widely assessed using field measurements by ecological methods, approaches for remotely sensing plant water status are largely lacking, particularly diurnal water status. In arid ecosystem, WUE is a dynamic indicator for detecting water status, but also an integrated index for correlating to the plant photosynthesis. In our study, the experiments were conducted on native dominant desert shrub, Tamarix ramosissima, in their original habitats on the southern periphery of Gurbantonggut desert, China. We explored sensitive and useful hyperspectral indices for estimating diurnal WUE at a leaf scale based on diurnal measurements of hyperspectral reflectance, photosynthesis and micrometeorological variables. According to the statistical analysis of relationships between spectral indices and WUE estimation, SR type hyperspectral index is the sensitivity index for WUE estimation. Our results provide useful insights for monitoring desert shrubs diurnal and dynamic water status, using a wide range of available hyperspectral data.

THE BIONOMICS OF TETRASTICHUS VERRUCARII (CHALCIDO-IDEA) WITH NOTES ON ITS HOSTS (NEUROTERUS SPP., CYNIPIDAE) ON BUR OAK

1929 ◽  
Vol 61 (6) ◽  
pp. 125-130
Author(s):  
W. V. Balduf
Keyword(s):  
Quercus Macrocarpa ◽  
The Family ◽  
Bur Oak

In an earlier volume (I) the writer presented observations on the bionomics of the parasites and inquilines from the galls of Disholcaspis mamma (Walsh) on a bur oak (Quercus macrocarpa) near Urbana, Illinois. Not less than fifteen species of Hymenoptera were then associated with that gall. In the last two years this gall and its several inhabitants were rare or lacking there, but the leaf galls of Neuroterus verrucarum O.S. and N. niger Gillette were abundant on the same tree. The larvae of the latter cynipids are heavily parasitized by a chalcid, Tetrastichus verrucarii Balduf of the family Tetrastichidae. Observations on the habits and stages of the parasite and its hosts are given below. These records incidentally extend the known hymenopterous fauna of the above tree by four or more species.

scholarly journals Hyperspectral Reflectance of Light-Adapted Leaves Can Predict Both Dark- and Light-Adapted Chl Fluorescence Parameters, and the Effects of Chronic Ozone Exposure on Date Palm (Phoenix dactylifera)

2020 ◽  
Vol 21 (17) ◽  
pp. 6441 ◽  
Author(s):  
Lorenzo Cotrozzi ◽  
Giacomo Lorenzini ◽  
Cristina Nali ◽  
Elisa Pellegrini ◽  
Vincenzo Saponaro ◽  
...  
Keyword(s):  
Precision Agriculture ◽  
Large Scale ◽  
Goodness Of Fit ◽  
Date Palm ◽  
Full Range ◽  
Ambient Air ◽  
Hyperspectral Data ◽  
Ozone Exposure ◽  
Plant Phenotyping ◽  
Spectral Models

High-throughput and large-scale measurements of chlorophyll a fluorescence (ChlF) are of great interest to investigate the photosynthetic performance of plants in the field. Here, we tested the capability to rapidly, precisely, and simultaneously estimate the number of pulse-amplitude-modulation ChlF parameters commonly calculated from both dark- and light-adapted leaves (an operation which usually takes tens of minutes) from the reflectance of hyperspectral data collected on light-adapted leaves of date palm seedlings chronically exposed in a FACE facility to three ozone (O3) concentrations (ambient air, AA; target 1.5 × AA O3, named as moderate O3, MO; target 2 × AA O3, named as elevated O3, EO) for 75 consecutive days. Leaf spectral measurements were paired with reference measurements of ChlF, and predictive spectral models were constructed using partial least squares regression. Most of the ChlF parameters were well predicted by spectroscopic models (average model goodness-of-fit for validation, R2: 0.53–0.82). Furthermore, comparing the full-range spectral profiles (i.e., 400–2400 nm), it was possible to distinguish with high accuracy (81% of success) plants exposed to the different O3 concentrations, especially those exposed to EO from those exposed to MO and AA. This was possible even in the absence of visible foliar injury and using a moderately O3-susceptible species like the date palm. The latter view is confirmed by the few variations of the ChlF parameters, that occurred only under EO. The results of the current study could be applied in several scientific fields, such as precision agriculture and plant phenotyping.

Bur oak (Quercus macrocarpa) biomass production on a former coal mine site: positive effects of coppicing on rapid recovery of growth and yield

2019 ◽  
Vol 49 (9) ◽  
pp. 1060-1068
Author(s):  
A. Mosseler ◽  
J.E. Major ◽  
D. McPhee
Keyword(s):  
Biomass Production ◽  
Coal Mine ◽  
Dry Mass ◽  
Height Growth ◽  
The Other ◽  
Rapid Recovery ◽  
Stem Height ◽  
Quercus Macrocarpa ◽  
Mine Site ◽  
Bur Oak

Ten-year-old bur oak (Quercus macrocarpa Michx.) saplings established on the exposed, infertile, treeless barrens of a former coal mine site in New Brunswick, Canada, were harvested to assess the effects of subsequent coppicing on regrowth parameters and biomass production. Two years after harvesting, coppice height growth exceeded that of the original 10-year-old saplings by 20%. Mean stem numbers were 1.2 and 6.7 for 10-year-old and coppiced trees, respectively. Mean dry mass recovered after 2 years with 214, 112, and 207 g for 10-year-old saplings and the 1- and 2-year-old coppices, respectively. Site quality of the broken shale rock overburden was similar across four of the five sites, with the exception that one site had twice the soil nitrogen (N) at 0.123% than the other four site types, which had an average of 0.064% N. This high N site had 2.3-fold the productivity of the mean for the other four sites. Mean coppice stem height showed the strongest predictive relationship to total coppice dry mass when compared with the greatest stem height, greatest or mean stem basal diameter, or coppice stem number. The most dramatic result of this bur oak coppicing experiment was the rapid recovery of height growth, biomass production, and observable stem quality within coppices over the 2-year period following harvesting of the original, 10-year-old saplings.

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