scholarly journals Sudden Phytophthora Dieback of Wild Cherry Trees in Northwest Hungary

2016 ◽  
Vol 12 (2) ◽  
pp. 117-124
Author(s):  
Judit Sárándi-Kovács ◽  
László Nagy ◽  
Ferenc Lakatos ◽  
György Sipos

Abstract During a regular survey of declining forests in 2011, sudden dieback symptoms were observed on scattered wild cherry trees (Prunus avium) in a mixed deciduous forest stand, located in the flood plain area of the Rába River, in northwest Hungary. In this study, we correlated both soil conditions and presence of Phytophthora spp. to dieback of cherry trees. Two Phytophthora species, P. polonica and P. plurivora, were isolated from the rhizosphere soil of the dying trees. By contrast, only P. polonica was recovered from the necrotic tissues of symptomatic roots. Stem and root inoculation tests on cherry seedlings showed pathogenicity of both species, although P. polonica proved to be more virulent. This is the first report of natural infections of P. polonica.

2008 ◽  
Vol 53 (No. 12) ◽  
pp. 555-560 ◽  
Author(s):  
I. Kupka

A large crown is one of the most important prerequisites for the good growth of a tree and therefore the crown could be called an engine of increment. The care for a large crown brings a decrease in the bole value at the same time as it makes large branches and later knots on it. Pruning is a possible solution of these two contradictions. Young wild cherry trees were pruned in three different ways: (<I>i</I>) half of the crown left, (<I>ii</I>) one quarter of the crown left and (<I>iii</I>) control, i.e. no pruning. The results show that height growth was not influenced by pruning while diameter growth was significantly affected. The crown reduction to a half means 10% less in diameter growth within a 5-year period after pruning. The crown reduction to one quarter of the crown means only two thirds of ‘full’ diameter growth on the control plot. The data suggest that the pruning of young wild cherry trees should be done moderately (more than a half of the crown should be left) and pruning should be done when the bottom part of the crown is in the shadow zone of the crown layer, not earlier.


2008 ◽  
Vol 53 (No. 3) ◽  
pp. 113-118
Author(s):  
I. Kupka

The root-plant ratio is one of the important parameters for planting stock quality. We suppose that the ratio is one of the driving variables for the growth performance of new plantation in the forest. The study summarises data on the volume of major parts of 4 years old wild cherry trees. An allometric analysis of different parts of plants in relation to the growth performance of wild cherry trees was done. The results show a close positive relationship between the volume of the whole root system and aboveground biomass. The same is true of the fine root proportion in the root system. Data also document that the efficiency of root system is not decreasing during the root development - at least in the investigated period. The same results were obtained for fine root efficiency. Data confirm the importance of the root-plant ratio for the growth performance of new plantation in the forest provided that harmful factors are not at a limiting level.


2021 ◽  
Vol 13 (3) ◽  
pp. 532 ◽  
Author(s):  
Rafael Bohn Reckziegel ◽  
Elena Larysch ◽  
Jonathan P. Sheppard ◽  
Hans-Peter Kahle ◽  
Christopher Morhart

Reduced solar radiation brought about by trees on agricultural land can both positively and negatively affect crop growth. For a better understanding of this issue, we aim for an improved simulation of the shade cast by trees in agroforestry systems and a precise estimation of insolation reduction. We present a leaf creation algorithm to generate realistic leaves to be placed upon quantitative structure models (QSMs) of real trees. Further, we couple it with an enhanced approach of a 3D model capable of quantifying shading effects of a tree, at a high temporal and spatial resolution. Hence, 3D data derived from wild cherry trees (Prunus avium L.) generated by terrestrial laser scanner technology formed a basis for the tree reconstruction, and served as leaf-off mode. Two leaf-on modes were simulated: realistic leaves, fed with leaf data from wild cherry trees; and ellipsoidal leaves, having ellipsoids as leaf-replacement. For comparison, we assessed the shading effects using hemispherical photography as an alternative method. Results showed that insolation reduction was higher using realistic leaves, and that the shaded area was greater in size than with the ellipsoidal leaves or leaf-off conditions. All shading effects were similarly distributed on the ground, with the exception of those derived through hemispherical photography, which were greater in size, but with less insolation reduction than realistic leaves. The main achievements of this study are: the enhancement of the leaf-on mode for QSMs with realistic leaves, the updates of the shadow model, and the comparison of shading effects. We provide evidence that the inclusion of realistic leaves with precise 3D data might be fundamental to accurately model the shading effects of trees.


1997 ◽  
Vol 62 ◽  
Author(s):  
R. Samson ◽  
S. Follens ◽  
R. Lemeur

A  multi-layer model (FORUG) was developed, to simulate the canopy  photosynthesis of a mixed deciduous forest during the growing season.  Measured photosynthesis parameters, for beech (Fagus  sylvatica), oak (Quercus  robur) and ash (Fraxinus  excelsior), were used as input to the model. This  information at the leaf level is then scaled up to the level of the canopy,  taking into account the radiation profiles (diffuse and direct PAR) in the  canopy, the vertical LAI distribution, the evolution of the LAI and the  photosynthesis parameters during the growing season, and the temperature  dependence of the latter parameters.


1999 ◽  
Vol 64 ◽  
Author(s):  
K. M. Tabari ◽  
N. Lust

Monitoring  of natural regeneration in a dense semi-natural mixed hardwood forest on the  base    of ash, beech, oak and sycamore occurred over 3 years in the Aelmoeseneie  experimental    forest, Belgium. 40 permanent plots (4 m x 5 m) were selected in three  various humus types,    located in an ash stand and in an oak - beech stand. In all plots abundance  and top height of all    broad leaved regenerated species were determined at the end of the growing  seasons 1995 and    1998. In addition, the seedlings which appeared in the plots during 1996  and 1997 were    identified and followed up.    This study proves that in the investigated sites natural regeneration is  drastically poor and    diversity is low, in particular where the humus layer is more acidic (mull  moder) and the litter    layer is thick. No regeneration phase older than the seedling stage (h &lt;  40 cm) is developed on    the different humus types. On average, total number of seedlings in 1995  amounts to 38    units/are in the ash stand and to 63 units/are in the oak - beech stand.  Survival rate over a 3-    year period is 37% and 42% respectively in the ash and oak - beech stands.  Total ingrowth    during the growing seasons 1996 and 1997 is virtually poor, indicating 16  and 8 units/are    respectively in above mentioned stands. Survival rate of occurring  seedlings, as well as the ingrowth of new seedlings are notably different (P &lt; 0.05) according to the soil conditions of the    ash stand. Generally, the low presence of seedlings and the lack of  regeneration older than the    seedling stage reveal that the regeneration development encounters with a  critical problem. The    continuation of this process would likely result in a progressive  succession by the invasive and    the unwanted tree species.


2020 ◽  
Vol 12 (15) ◽  
pp. 2359
Author(s):  
Víctor Blanco ◽  
Pedro José Blaya-Ros ◽  
Cristina Castillo ◽  
Fulgencio Soto-Vallés ◽  
Roque Torres-Sánchez ◽  
...  

The present work aims to assess the usefulness of five vegetation indices (VI) derived from multispectral UAS imagery to capture the effects of deficit irrigation on the canopy structure of sweet cherry trees (Prunus avium L.) in southeastern Spain. Three irrigation treatments were assayed, a control treatment and two regulated deficit irrigation treatments. Four airborne flights were carried out during two consecutive seasons; to compare the results of the remote sensing VI, the conventional and continuous water status indicators commonly used to manage sweet cherry tree irrigation were measured, including midday stem water potential (Ψs) and maximum daily shrinkage (MDS). Simple regression between individual VIs and Ψs or MDS found stronger relationships in postharvest than in preharvest. Thus, the normalized difference vegetation index (NDVI), resulted in the strongest relationship with Ψs (r2 = 0.67) and MDS (r2 = 0.45), followed by the normalized difference red edge (NDRE). The sensitivity analysis identified the optimal soil adjusted vegetation index (OSAVI) as the VI with the highest coefficient of variation in postharvest and the difference vegetation index (DVI) in preharvest. A new index is proposed, the transformed red range vegetation index (TRRVI), which was the only VI able to statistically identify a slight water deficit applied in preharvest. The combination of the VIs studied was used in two machine learning models, decision tree and artificial neural networks, to estimate the extra labor needed for harvesting and the sweet cherry yield.


1960 ◽  
Vol 40 (4) ◽  
pp. 707-712 ◽  
Author(s):  
W. H. A. Wilde

Little cherry virus disease of sweet cherry (Prunus avium L.) was transmitted under screenhouse conditions by 3 species of leafhoppers (Homoptera: Cicadellidae) out of 24 species tested. Macrosteles fascifrons (Stal), the 6-spotted leafhopper, transmitted the disease in seven tests; Scaphytopius acutus (Say), the sharp-nosed leafhopper, transmitted it once; and Psammotettix lividellus (Zett.) transmitted it once. The transmissions were made from diseased sweet cherry trees of the variety Lambert to indicators of the varieties Star or Sam. With the exception of 1 transmission, 2 to 4 years were necessary following inoculation for unmistakable expression of symptoms in the indicators. M. fascifrons was also implicated in 18 successful transmissions to mature sweet cherry trees grown in the open.


Nature ◽  
1950 ◽  
Vol 165 (4184) ◽  
pp. 23-24
Author(s):  
E. P. STEBBING

2013 ◽  
Vol 13 (2) ◽  
pp. 133-140 ◽  
Author(s):  
Khet R Dahal ◽  
Chandra P Poudyal ◽  
Prajwal Adhikari ◽  
Subodh Sharma ◽  
Jitendra Ghimire

CORRECTION: The correct PDF for this article was loaded on 22/04/2013.The study was carried out in the vicinity of the Tinau river, Rupandehi, Nepal from July 2011 to June 2012. Ten number of shallow tube wells (STWs) of depths 5.18 m to 7.62 m, four shallow tube wells (STWs) of depths 28.96 m to 36.58 m. from Amawa and Farsatikar Village Development Committees and one dug well (DW) from Butwal Municipality were selected for the purpose of this study. The depth of the STWs was different but many STWs were of 6.09 m deep. The DW was of 18.29 m. The information was collected from the owners during field visit of the sites. A standard questionnaire was prepared and asked to the affected persons. The site observation was done in the dry season as well as in the rainy seasons. It was found that the extraction of riverbed materials from the river channel and the flood plain area has adversely affected the aquatic environment of the Tinau river. Massive extraction of the riverbed materials from this river started after the enforcement of local governance act, and regulation 1999. The income generated from the riverbed materials is quite enough. This is one of the major sources of income generation of DDC Rupandehi and the VDCs attached to this river (from Butwal to Bethari). The depth of the river increased due to extraction activities as a result groundwater table lowered. The STWs having depth of 5.18 to 7.62 m stopped discharging water from the aquifer in the dry season. Similarly DW of Butwal municipality having depth of 18.29 m stopped discharging water at dry season. But the STWs of depths from 28.96 m to 36.58 m. located at the same area/site were not affected by the extraction in the Tinau river. The people, who are residing on the bank of the river Tinau, suffered from drinking water problem because they are using the water from STWs. The effect is directly facing the people of low and medium level having low income generation. The extraction activity is going on and the deficit of water availability in STWs and DW is common in the vicinity of the Tinau river especially in the upstream (from Butwal to Paschim Amawa), whereas there is less effects of riverbed extraction for STWs of depths more than 27.43 m in the same sites. Nepal Journal of Science and Technology Vol. 13, No. 2 (2012) 133-140 DOI: http://dx.doi.org/10.3126/njst.v13i2.7726


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