Effect of drought stress and infestation by the balsam woolly adelgid (Homoptera: Adelgidae) on abnormal wood production in Fraser fir

1994 ◽  
Vol 24 (11) ◽  
pp. 2295-2297 ◽  
Author(s):  
Robert G. Hollingsworth ◽  
Fred P. Hain

Fraser fir (Abiesfraseri (Pursh) Poir.) seedlings were artificially infested with balsam woolly adelgid, Adelgespiceae (Ratz.), then subjected to drought-stress treatments. Infestation caused a distinct swelling in the main stem, caused by the accumulation of abnormal wood (i.e., "rotholz"). As expected, drought stress reduced diameter growth in the main stem. However, the reduction in wood increment caused by drought stress was relatively small for infested seedlings as compared with uninfested seedlings, owing to the production of rotholz. This implies that infested trees expend considerable energy and nutrients for the production of poorly functioning wood even during periods of stress. The implications of this research for interpreting patterns of tree mortality in the southern Appalachian Mountains are discussed.

IAWA Journal ◽  
1991 ◽  
Vol 12 (3) ◽  
pp. 235-239 ◽  
Author(s):  
Robert G. Hollingsworth ◽  
Udo Blum ◽  
Fred P. Hain

Potential sapwood flow rates were measured for Fraser fir sterns that previously had been infested by the balsam woolly adelgid. The amount of abnormal wood produced during infestation was inversely related to the flow rate and linearly related to the amount of heartwood area. These results support the hypothesis that abnormal wood production associated with adelgid infestation can lead to water stress in the crowns of infested trees. The data also suggest that adelgid infestation accelerates the formation of heartwood.


1991 ◽  
Vol 21 (11) ◽  
pp. 1639-1648 ◽  
Author(s):  
V. H. Dale ◽  
R. H. Gardner ◽  
D. L. DeAngelis ◽  
C. C. Eagar ◽  
J. W. Webb

The pattern of distribution of endemic Fraser fir (Abiesfraseri (Pursh) Poir.) in the southern Appalachian Mountains is being affected by infestation of the exotic balsam woolly adelgid (BWA) (Adelgespiceae (Ratz.)). BWA kill mature fir trees in about 3–9 years after initial infestation. Prediction of the effects of BWA in a forest region requires an assessment of (i) the population dynamics of the BWA and the fir, (ii) the prevailing physical conditions that affect the spread of BWA, and (iii) the subsequent pattern of fir mortality. This paper predicts the patterns of fir mortality and recovery on an elevation gradient by using a population model with site-specific environmental conditions and ecological interactions. The model shows that temperature range and amplitude, which affect the survival and development rates of BWA, can have an indirect influence on the spatial pattern of living trees. The model results suggest that persistence of both species, with oscillations in numbers over time and space, is probable.


1994 ◽  
Vol 24 (11) ◽  
pp. 2284-2294 ◽  
Author(s):  
Robert G. Hollingsworth ◽  
Fred P. Hain

Fraser fir, Abiesfraseri (Pursh) Poir., seedlings were grown in the greenhouse and at four field sites in the southern Appalachian Mountains to study the effects of infestation by the balsam woolly adelgid (BWA), Adelgespiceae (Ratz.). Swelling in the main stem was used as an indicator of abnormal wood (i.e., "rotholz") production induced by infestation. At three of the four field sites, the main stems of infested seedlings were significantly more swollen than those of uninfested seedlings. The amount of swelling caused by BWA generally was not affected by seed source (half-sib family), soil source (soil from higher or lower elevations), or interactions of these variables. At two of four field sites, infestation was associated with a significant increase in root:shoot ratio. Variability in root:shoot ratios and total dry weights of seedlings was influenced by interactions of infestation, soil source, and seed source. This result demonstrates that both tree genetics and environment play a significant role in the growth responses of infested Fraser fir seedlings. Results from the greenhouse study indicated that BWA might be represented by two or more biotypes in the southern Appalachians. Shoot weights and diameter increases were relatively large for Mount Mitchell seedlings infested by BWA from Mount Rogers, and relatively small when infested by BWA from Mount Mitchell. For seedlings from Mount Rogers, the converse was true. Overall, these results suggest that environment is probably more important than tree or insect genetics in explaining why so many infested trees have died in the Black Mountains of North Carolina.


2011 ◽  
Vol 9 (2) ◽  
pp. 291-295 ◽  
Author(s):  
Ilona Czyczyło-Mysza ◽  
Izabela Marcińska ◽  
Edyta Skrzypek ◽  
Małgorzata Chrupek ◽  
Stanisław Grzesiak ◽  
...  

Drought is one of the major factors limiting wheat yield in many developing countries worldwide. Parameters of chlorophyll a fluorescence kinetics under drought stress conditions have been used to characterize dehydration tolerance in wheat. In the present study, a set of 94 doubled haploid lines obtained from Chinese Spring × SQ1 (CSDH), mapped with 450 markers, was evaluated for yield (grain dry weight/main stem ear), number of grains/main stem ear (NG) and chlorophyll a fluorescence parameters (FC) under moderate and severe drought stress, and compared with results for well-watered plants. quantitative trait loci (QTLs) were identified using Windows QTLCartographer version 2.5 software and the results were analysed using single-marker analysis (SMA) and composite interval mapping (CIM). Analysis using SMA and CIM showed mostly similar QTLs for all traits, though more QTLs were identified by SMA than by CIM. The genetic control of yield, NG and FC varied considerably between drought-stressed and non-stressed plants. Although no major QTL co-locations were found for yield and FC using CIM, the co-location of QTLs for NG, yield and Fv/Fm in drought-stressed plants was observed on chromosome 5A using SMA.


Holzforschung ◽  
2005 ◽  
Vol 59 (5) ◽  
pp. 488-496 ◽  
Author(s):  
Mikhail Yu. Balakshin ◽  
Ewellyn A. Capanema ◽  
Barry Goldfarb ◽  
John Frampton ◽  
John F. Kadla

Abstract The composition of mature, juvenile uninfested and juvenile infested Fraser fir wood (Rotholz) and the structures of lignins isolated from these woods were elucidated to verify differences between juvenile and mature wood and the effect of balsam woolly adelgid (BWA) infestation. Milled wood lignin (MWL) isolated from mature, juvenile and Rotholz wood were comprehensively characterized using heteronuclear multiple quantum coherence (HMQC) and quantitative 13C NMR techniques. The Rotholz wood was found to have ∼13% higher lignin content and more than five-fold the amount of galactans than that of the uninfested wood. Rotholz lignin possesses higher amounts of p-hydroxyphenyl units and aliphatic OH groups and a lower amount of alkyl-O-alkyl linkages and dibenzodioxocin moieties. The degree of condensation of the Rotholz lignin was rather similar to that of normal wood. Only small differences in the structure of mature and juvenile wood components were found.


1992 ◽  
Vol 22 (12) ◽  
pp. 1937-1948 ◽  
Author(s):  
R. Ceulemans ◽  
G. Scarascia-Mugnozza ◽  
B. M. Wiard ◽  
J. H. Braatne ◽  
T. M. Hinckley ◽  
...  

Height and diameter growth, stem volume production, leaf phenology and leaf number, and number of branches of Populustrichocarpa Torr. & Gray, Populusdeltoides Bartr., and their F1 hybrids (P. trichocarpa × P. deltoides) were studied for 4 years in a research plantation in western Washington, United States. Twelve clones (three of each species and six of the hybrids) grew under a short-rotation silviculture regime in monoclonal plots at spacings of 1 × 1 m (10 000 stems/ha). Clones represented a north-south gradient within the geographic distribution of both the two North American poplar species and the parentage of the hybrid material. The results support earlier work by contributing additional evidence for the superiority of the hybrids. However, the relative hybrid superiority in these monoclonal plots was less pronounced than that found earlier in field trials with single-tree plots because of heightened intraclonal competition. After 4 years, mean estimated stem volume of the hybrids was 1.5 times that of P. trichocarpa and 2.3 times that of P. deltoides. Total tree height of the hybrids was 1.1 times that off. trichocarpa and 1.3 times that off. deltoides. Clonal variation was the dominant theme in height and diameter growth, stem volume productivity, time of bud break and bud set, tree mortality, and number of branches. Populustrichocarpa had the highest number of sylleptic branches, P. deltoides had the lowest, and hybrids were intermediate. Significant clone by replicate interactions were observed in height, diameter, and volume growth. Phenological traits, such as the dates of bud break and bud set, and the length of growing period only partly explained the observed differences in growth between the P. trichocarpa × P. deltoides hybrids and the parental species.


2006 ◽  
Vol 7 (1) ◽  
pp. 25 ◽  
Author(s):  
D. M. Benson ◽  
J. R. Sidebottom ◽  
J. Moody

Fungicides were evaluated for control of Phytophthora root rot for five growing seasons in two field plantings of Fraser fir (Abies fraseri) affected by Phytophthora cinnamomi in western North Carolina. At the first site, which had a fairly well-drained soil, treatment programs with Aliette (5 lb/100 gal, three applications per year), Subdue Maxx (3.7 fl oz/1.15 gal/1000 ft2, two applications per year), and Subdue GR (5.75 lb/1000 ft2, two applications per year) maintained low rates of mortality (< 10%) for three growing seasons, whereas tree mortality in the untreated plots reached 13 and 37% by the second and third growing seasons, respectively. At the second site, which was in a flood plain, disease did not develop during the first 2.5 years, even in untreated control plots. However, mortality increased rapidly following several high-rainfall events, but none of the fungicides had any effect on disease development. Apparently, at least under conditions not overly conducive to the disease, the fungicide treatment programs can delay the onset of high mortality rates caused by P. cinnamomi in Fraser fir for up to three growing seasons. Accepted for publication 23 February 2006. Published 31 March 2006.


2006 ◽  
Vol 36 (4) ◽  
pp. 878-885 ◽  
Author(s):  
J M Wolken ◽  
P V Blenis ◽  
I Duncan

The probability of lodgepole pine (Pinus contorta Dougl. ex Loud.) having main-stem galls caused by western gall rust, Endocronartium harknessii (J.P. Moore) Y. Hiratsuka, surviving to rotation is unknown. To evaluate survival, 400 galled trees with at least one stem gall and 400 trees without stem galls were measured in 1992 in two precommercially thinned stands approximately 20 years old. The survival of trees was assessed in 2003. Nonlinear regression using iteratively reweighted least squares was employed to estimate the survival of galled trees as a function of the proportion of the main stem encircled by galls. Galls encircling >79% and >91% of the stem in the two stands increased the risk of mortality relative to non-galled trees, with the risk increasing steeply with percent gall encirclement; smaller stem galls did not cause tree mortality. The 11-year pattern of survival of galled trees was similar for infections that occurred on the main stem and those that had reached the stem from a nearby branch infection. Based on an earlier model of gall expansion, 38%–43% of stem-galled trees would be expected to survive until age 80. Scribing of stem galls to prevent their expansion does not appear to be a feasible management strategy.


Sign in / Sign up

Export Citation Format

Share Document