IOBC-WPRS Shop: ePublications

View basket

IOBC-WPRS Bulletin Vol. 57, 2010

 

IOBC-WPRS Bulletin Vol. 57, 2010

Working Group "Integrated Protection in Oak Forests".
Proceedings of the meeting at Tlemcen (Algeria), 25 - 28 October 2007.
Edited by: C. Villemant, R. T. Bouhraoua and E. Sousa.
ISBN 978-92-9067-231-9 [xiv + 206 pp.]

 

0.00 €

 

 

 

 

Add this product to your basket

Articles

Pages

Price

Cart

Biogeography of north African cork oak (Quercus suber L.)
Simeone, M. C., Vessella, F., Salis, A., Larbi, H., Schirone, A., Bellarosa, R., Schirone, B.

Abstract: Several issues regarding the extent of genetic variation in the cork oak (Quercus suber
L.), and the evolutionary forces that shaped its biogeography are still unknown and controversial.
New insights to infer intra-specific phylogeographic relationships in the previously neglected
North African cork oak stands are here provided by means of genetic analyses of the maternally
inherited plastid genomes (PCR-RFLP at 5 chloroplast loci). We have analysed 17 populations
from Morocco (7), Algeria (6) and Tunisia (4); resulting data were included in a
phylogeographical framework obtained from 95 populations throughout the species range. Five
total haplotype lineages were identified for the entire species’ range. Of these, three haplotypes
occur along the North African Mediterranean coast, delineating two clear suture zones: at East
(Northeastern Algeria) and at West (Central Morocco). Genetic diversity parameters were
determined for the different geographic areas of the entire species range, showing interesting
variation where paleogeography, hybridization, adaptation, fragmentation, and human impact all
play an important role.
The importance of the North African territories for the evolutionary history of the species
and the urgency for measures to preserve the current biodiversity in this area are stressed.

1-8

0.00 €

 

Importance of Quercus cerris on diversity of European oak gall wasps (Hymenoptera:
Cynipidae): the role of glacial refuges on the cynipids and their postglacial expansion

Pujade-Villar, J.

Résumé: Les Cynipidés sont des micro-hyménoptères gallicoles. La majorité des espèces qui
évoluent sur les chênes (Quercus spp.) ont des cycles alternatifs, la plupart sont hétérogoniques
mais quelques autres sont hétéroéciques. Cette étude présente les différents modèles de cycles
biologiques de la tribu des Cynipini dans la zone paléarctique occidentale et met en évidence
l'importance des refuges glaciaires sur leur biologie et leurs modalités de reproduction, selon la
présence ou l'absence de Q. cerris, et leur signification dans la biodiversité actuelle. On notera
qu’il est possible mais rare que l’apparition d’espèces jumelles dépende d’un changement d'hôtes.
Les différences de diversité existant actuellement entre les zones paléarctiques orientale et
occidentale sont la conséquence directe du type de refuge glaciaire et de l'expansion de Q. cerris
liée à l’activité humaine.

9-17

0.00 €

 

Degradation of Tlemcen oak forest (Algeria). Which impact on the avian diversity?
Mostefai, N., Robert, A.

Abstract: The Mediterranean basin is one the most threatened “hot spots” of biodiversity in the
world due to the important destruction level of its habitats. During the last years, Tlemcen oak
forests suffered strong degradations caused by repeated fires and human activity pressure, notably
overgrazing. We analyzed the impact of habitat degradation on the avian biodiversity by
comparing biodiversity measures such as richness, abundance and diversity indices in four oak
forest habitats showing increasing degradation levels. In all cases, the habitat degradation level
explained more than 60% of the variance of these indices. The most degraded habitats suffered
the strongest biodiversity loss. On the other hand, the functional avian community groups also
appeared to be affected by habitat degradation: the decreasing number of forest specialist and
generalist species along the gradient of habitat disturbance benefited to the open field species.
These results confirmed that it is necessary to perform urgent conservation actions notably in
mature and degraded oak forests.

19-23

0.00 €

 

Cork's macroscopic and microscopic characterization according to the sanitary state
of the tree in two zones of production in the west Algerian

Dahane, B., Bouhraoua, R. T., Berrichi, M.

Abstract: The influence of the sanitary status of the trees on the macroscopic and microscopic
structure of the cork was studied in two Algerian zones of cork production: coastal (M’Sila) and
mountainous (Zarieffet). Cork samplings were performed on 43 healthy trees (foliar deficit
<25%) and 19 declining trees (foliar deficit >60%). The macroscopic study showed that cork
growth varies in relation to the ecological zone of origin. In mountain, the cork of the healthy
trees, that grows slowly, has more small sized pores (section <1mm) than that of the coastline
which possesses 45% of large pores (section >2mm). In the cork of the declining trees, the
slowing down of the growth induced an increasing number of small pores. The microscopic
structure of the cork also proved to be linked with the growth speed. On healthy trees, the size of
the cork cells (H/L index) reached 1.41 in the littoral, versus 1.09 in the mountain. On the other
hand, the cell wall thickness is inversely correlated to cell size. The structure of the cork generally
determines its quality. Healthy cork-oaks from mountain produced better cork (less flexible) than
those from the littoral.

25-32

0.00 €

 

Study of the cork quality of the oriental cork oak stands of Tizi-Ouzou
Messaoudène, M., Metna, B.

Abstract: The thickness, porosity, suberin content and some physical properties of the corks were
studied in five stations of the oriental cork oak forest of Tizi-Ouzou (Algeria) in order to
characterize the cork quality. The results showed the “tree effect” and the “station effect” on the
characters of the cork. The heterogeneity of the characters within the same forest poses the
problem of ranking the quality of cork according to station or type of cork oak forest;
individualized groups having no relation with a given ecological gradient of the station. The
analyzed corks belonged to the category of fair and regular cork, moderately porous, weakly
absorbent and relatively flexible. They can be used to produce stoppers. The study showed that
the station of Tawrirt, which underwent sylvicultural management, produced the best cork.

33-40

0.00 €

 

Influence of decline on the yearly growth of in some cork-oak stands of western Algeria
Dahane, B., Bouhraoua, R. T.

Abstract: Cork growth characteristics of two cork-oak stands of western Algeria: M’Sila on the
coastline and Zarieffet in the mountain were studied from a sample of 43 healthy and 19 declining
oaks. Pieces of cork were taken in summer 2005 and their yearly increase measured using a
micrometer. On the littoral, the cork of the healthy trees showed a fast to middle growth speed,
with an average annual increase of 2.42mm. In mountain, however, the growth speed showed
rather a middle to weak growth type with an average annual increase of 1.86mm. For declining
trees, cork increases were smaller and varied on average between 1.87 mm/year (in M'Sila) and
1.01 mm/year (in Zarieffet), thus representing a 46% reduction of cork growth between coast and
mountain oaks. Such differences must be taken into account when establishing the rotation
rhythm of debarking in each cork-oak stand.

41-44

0.00 €

 

Structural study of the cork oak forest of Hafir-Zariffet (West Algeria)
Letreuch-Belarouci, A. M., Letreuch-Belarouci, N., Medjahdi, B., Benabdeli, K.

Abstract: The study took place in the Tlemcen National Park (West Algeria). It aimed at
characterizing the structure of different cork-oak stands damaged by fire in 2004. Three
parameters were recorded (tree species composition, density and diameter class distribution) in 17
plots of 10 ares each. Four structure groups resulting from intense and repeated disturbances of
the forest were recognized. Various actions for the reconstitution of the vegetation cover and
silvicultural interventions for the rehabilitation of cork-oak stands are proposed in relation to
stand structure.

45-52

0.00 €

 

Observations on tree decline of different cork oak (Quercus suber L.) provenances in
the experimental site of Tebaba, North-western Tunisia

Larbi Khouja, M., Ben Jamâa, M. L., Franceschini, A., Khaldi, A., Nouri, N., Sellemi, H., Hamrouni, L.

Abstract: In the framework of the EUFORGEN project, an experimental field of 26 provenances of
cork oak from several Mediterranean countries was set up since 1997 in two sites (Tebaba and
Hanya) located in the North-western Tunisia and characterized by humid bioclimate. Until 2005
the plants in the site of Tebaba didn’t show any symptom of weakness or decay. However, in
September 2006 different decay degrees of the provenances were registred in the same site.
In order to evaluate the damage severity, four classes of crown dieback (for 1/3, 1/2, 2/3, and
whole crown) were considered. The results showed that 24% of the present trees (2340) are
affected, and 87% of these completely died. The provenance of Makna (Tunisia) appeared to be
the most sensitive, while that of Fuencaliente (Spain) was the least affected. The analyses carried
out on different tree parts (shoots, branches, stem, roots) showed the presence of various
pathogenic agents, some of which seem to be involved in aetiology of the tree decline, i.e.
Biscogniauxia mediterranea, Discula quercina, Hypoxylon sp., and Phomopsis sp. However, no
soil pathogens were found.

53-59

0.00 €

 

Quercus coccifera L., Quercus suber L., fruit extracts: a suitable natural source of
antioxidants and antimicrobial, namely against phytopathogen fungi

Hayouni, E. A., Saouli, A., Ouakid, M. L., Hamdi, M.

Abstract: The application of insecticides and synthetic antibiotics is currently the common
method to control or eradicate pest animals and plants. Many of these chemicals have non
specific properties and side effects. Plants synthesise a vast array of secondary metabolites that
are gaining importance for their biotechnological applications. The aim of this work was to assess
the effect of different solvents on the antifungal and the antioxidant activity of some extracts
obtained from the healthy acorns of Tunisian Quercus coccifera L. and the infested acorns of
Algerian Quercus suber L., found fallen on the soil. Water and organic solvents such as acetone,
ethanol and chloroform significantly affected the total polyphenol content (44.6 to 173mg GAE/g
dry weight extract). Results showed a strong correlation between polyphenol contents and the
antioxidant potential of these extracts (correlation ranging between R2 = 0.82 and R2 = 0.91).
It is also noteworthy that most of the extracts, obtained from both populations of Quercus,
showed a significant and dose-dependant antifungal activity as assessed by the well diffusion
assay against the majority of tested phytopathogens. It is worth to note that extracts from infested
fruits of Q. suber exhibited greater antifungal activity apparently associated with a different
phenolic compounds pattern, after infestation by larvae; probably responsible for a deep
biochemical transformation that gave a disparate chemical profile. The results could be very
helpful to formulate an alternative explanation for the apparent relationship between changes in
phenolic content and insect predation. Thereby, some of these extracts could be suitable for use in
biological control namely as safe anti-fungal in agriculture to control or eradicate crops, fruits and
postharvest pests.

61-68

0.00 €

 

Fungi associated with canker and dieback diseases of Quercus suber in Tunisia
Linaldeddu, B. T., Hasnaoui, F., Franceschini, A.

Abstract: Decline events have recently been observed in several cork oak forests in northwest
Tunisia (Kroumirie). The affected trees show crown thinning, leaf yellowing, branch dieback,
cankers, epicormic shoots and exudates on branches and trunk. Six fungi isolates: Biscogniauxia
mediterranea, Botryosphaeria corticola, Cytospora sp., Discula quercina, Fusicoccum sp. and
Pleurophoma cava were constantly isolated from cankered and wilted branches of affected plants.
Pathogenicity tests on 3-year-old cork oak seedlings confirmed the virulence of all species. The
results obtained emphasize the need to develop further research into the real incidence and
distribution of these and other pathogens, which are potentially involved in the aetiology of
decline in the Tunisian cork oak forest.

69-71

0.00 €

 

Evaluation of cork and holm oak seedling viability to Phytophthora cinnamomi
infection treated with compost and mycorrhizae fungi

Moreira, A. C., Domingos, A. C., Fontes, A. M., Semedo, J., Melo, E., Machado, H., Reis, M., Horta, M., Cravador, A.

Abstract: Phytophthora cinnamomi is a soil borne plant pathogen involved in oak decline that
caused a high mortality in cork oak and holm oak trees in Portugal. We evaluated the
development of oak seedlings from different origins submitted to different treatments. Acorns
were collected in 12 regions of Portugal and Spain. A direct sowing was carried out following
two treatments: 1) in soil naturally infested with P. cinnamomi; 2) in the same soil corrected with
the addition of chemically and microbiologically characterized vegetal compost. In greenhouse,
pre-germinated acorns were sown in pots filled with: A) a mixture of a soil naturally infested with
P. cinnamomi, collected from a field with high disease incidence; B) the same mixture plus a
vegetal compost; C) the same mixture as A inoculated with mycorrhizae fungi collected from
cork oak stands. Preliminary results from evaluation at six months showed that the compost
improved the germination of both species in field conditions, even in the presence of P.
cinnamomi.
Under controlled conditions, a better development was observed on infected oak
seedlings submitted to the compost treatment. These preliminary results suggested that using
compost is a useful cultural practice that may reduce P. cinnamomi impact.

73-76

0.00 €

 

Efficacy of oak endophytic fungi in controlling the infections of Botryosphaeria orticola
in cork oak trees

Linaldeddu, B. T., Maddau, L., Corda, P., Franceschini, A.

Abstract: Botryosphaeria corticola is one of the most virulent pathogens involved in the
aetiology of cork oak decline in Mediterranean countries. Its attacks are often subsequent to cork
extraction and cause cankers, vascular necrosis and dieback in healthy or declining trees. Given
the high susceptibility of cork oak to endophytic infections of B. corticola and the spread of this
pathogen inside cork oak forests, suitable prevention measures, such as the application of biopesticides,
should be taken in order to limit the damage. Therefore, research was carried out to
evaluate in planta the bio-control activity of three oak endophytic fungi: Bionectria solani,
Dictyochaeta parva and Trichoderma sp., selected for their marked antagonistic activity in vitro
against B. corticola. The results showed that all three fungi were able, in all seasons, to colonize
the artificially damaged branch tissues of cork oak trees. Moreover, they significantly reduced
both the length of necrotic lesions and the incidence of branch mortality caused by B. corticola.
The most active were Trichoderma sp. and chiefly B. solani. In the summer tests, B. solani
reduced branch mortality by up to 100%. All branches inoculated only with the endophytic fungi
showed no disease symptoms. These results suggested that the selected strains of B. solani and
Trichoderma sp. are good candidates for developing new biological control formulations both in
nursery and in forest of cork oak against endophytic infections of B. corticola.

77-84

0.00 €

 

Occurrence of entomopathogenic nematodes and fungi in oak wood soils from southern Italy
Tarasco, E., Triggiani, O.

Abstract: The natural occurrence of entomopathogenic nematodes and fungi was investigated in
oak wood soils from southern Italy using the Galleria baiting technique, from September 2005 to
June 2007. The sampling was performed in 160 different sites with 5 different oak species:
Quercus ilex L., Q. trojana Webb., Q. cerris L., Q. frainetto Tenore and Q. pubescens Wild.
Almost 16% of oak stands were positive for the presence of entomopathogenic nematodes:
Steinernema feltiae (Filipjev, 1934) Wouts, Mráček, Gerdin and Bedding, 1982 and S. affine
(Bovien, 1937) Wouts, Mráček, Gerdin and Bedding, 1982 were the species collected. S. affine
was the most common species. Parasitic fungi were obtained from 69 sites (43%). 3
entomopathogenic species were recorded: Beauveria bassiana (Balsamo) Vuillemin, the most
common species, Metarhizium anisopliae (Metchnikoff) and Paecilomyces lilacinus (Thom)
Samson; Penicillium sp., Aspergillus sp. and Fusarium sp. (common species in soils with no
entomopathogenic potential) were also isolated.

85-86

0.00 €

 

Mycobiota associated with Platypus cylindrus Fab. (Coleoptera: Platypodidae) on cork oak in Portugal
Inácio, M. L., Henriques, J., Sousa, E.

Abstract: Platypus cylindrus populations outbreaks observed in the last decades are related to
cork oak decline in Portugal, as in other Mediterranean countries. Being an ambrosia beetle, it
feeds on fungi that carries and inoculates in galleries excavated in host trees. To study this
mycobiota, fungi were isolated from the beetles (mycangia, intestine and exoskeleton) and cork
oak galleries. Several fungi were identified, namely Raffaelea (Ascomycota, Ophiostomatales)
and Nodulisporium (asexual stage of Biscogniauxia mediterranea), possibly implicated in host
weakness. The other isolated fungi, particularly Gliocladium, Scytalidium and Trichoderma
genera, might be involved in processes such as insect feeding, wood degradation and fungal
antagonism in the galleries.

87-95

0.00 €

 

Antagonistic activity and molecular characterization of isolates of Pisolithus spp. from
the Maamora forest (Morocco)

Belkouri, A, Yakhlef, S. B., Es-sgaouri, A., Aouadj, R., Abourouh, M.

Abstract: The antagonistic activity of 8 isolates of Pisolithus spp. associated with Quercus suber
and Eucalyptus spp. was studied in vitro against 5 phytopathogenic fungi (Armillaria mellea,
Botrytis cinerea, Curvularia lunata, Fusarium oxysporum and Helminthosporium maydis) in
order to select the isolates showing the highest antagonistic activity. These isolates showed
different level of antagonistic activity against the tested pathogens. Antagonism by direct
confrontation was confirmed by using the liquid culture filtrate of the isolates. The molecular
analysis with ITS-RFLP restriction enzymes HinfI, MspI and TaqI, allowed the identification of a
single genotype for isolates of Pisolithus from eucalyptus and two genotypes from cork-oak.

97-101

0.00 €

 

Platypus cylindrus Fab. (Coleoptera: Platypodidae) control strategies
Henriques, J., Inácio, M. L., Pires, S., Sousa, E.

Abstract: The oak pest Platypus cylindrus Fab. (Coleoptera: Platypodidae) is encountered
throughout Eurasia and Mediterranean area, including North Africa; it is thus present in all the
main cork oak producing countries. This ambrosia beetle carries symbiotic fungi that it inoculates
in galleries excavated in the tree. The insect can affect the host as both wood borer and vector of
potentially pathogenic fungi. In order to perform P. cylindrus control, it is essential to adopt
preventive management strategies that improve the tree physiological state, favour the auxiliary
fauna occurrence and maintain a good sanitary level of cork oak stands. So far, direct control of
insects’ populations has not been achieved. In some countries, insecticides have been used but
their application in cork oak stands is not advisable and their final effect is limited. Using
attractants to control this species constitutes a tool of great interest. A P. cylindrus aggregation
pheromone has been identified as a mixture of hexanol, sulcatol and sulcatone, as well as a
kairomone composed by α-thujone, camphen and β-pinen. Both substances are under study.
Understanding the insect-fungi interactions can lead to the establishment of indirect control
measures by inhibiting the associated mycobiota. Testing the use of fungicides is in progress for
limited applications; taking advantage of natural antagonistic relations between specific fungi
might be an interesting new option.

103-106

0.00 €

 

Observations on the attacks and biological characteristics of Platypus cylindrus F.
(Coleoptera: Platypodidae) in Tunisia

Ben Jamâa, M. L., Sousa, E., M’nara, S.

Abstract: The study carried out in Tunisia in 2004 and 2005 aimed at characterizing the trees
attacked by Platypus cylindrus and determinating the adult flying period. Results were compared
with those obtained in Portugal between 1993 and 1995. While it attacks healthy trees in
Portugal, P. cylindrus mostly attacks weakened trees in Tunisia. The high level of debarking
index seems to favour the beetle attack in Tunisia. The P. cylindrus adults fly from early June to
early October in Tunisia, while in Portugal, adult flight begins from early May may sometimes
finish only in January.

107-114

0.00 €

 

Damages from white grubs in young cork oak plantations of the Mamora forest:
biology and proposal of chemical control against the most important species

Ghaioule, D., El Antry, S., Atay-Kadiri, Z., Lumaret, J. P.

Abstract: During cork oak regeneration tests performed in the Mamora forest, seedlings suffered
massive attacks from white grubs. Their mortality rate reached 41 to 68% according to years and
sites. Sphodroxia maroccana Ley (Coleoptera; Melolonthidae), an endemic species of the
Mamora forest, is the main pest present in the regeneration parcels. The other causes of seedling
withering are principally the summer drought and weeding work. The polyphagous opportunistic
S. maroccana became obviously a pest under unbalanced anthropogenic influence. Adults appear
every year in summer, since early June till mid-September. The life-cycle lasts up to five years
for females and three years for males. The female, larger than the male, is unable to fly. The
larvae attack roots and collars of cork oak seedlings. Chemical control achieved by using
granulate systemic insecticides (Carbosulfan 10% and Chlorpyrifos 10%) induced a significant
decrease of seedling mortality.

115-122

0.00 €

 

Bioecology of Orgyia trigotephras (Boisduval, 1829), (Lepidoptera, Lymantriidae) in
Jebel Abderrahman, Cap Bon (North East of Tunisia)

Ezzine, O., Ben Jamâa, M. L., M’nara, S., Nouira, S.

Abstract: The biology of Orgyia trigotephras and its impact on various species of the Kermes
oak bush have been studied in the forest of Jebel Abderrahman (Cap Bon, North-East of Tunisia),
after a significant defoliation caused by this insect during 2005. We studied the development
duration of the larval and pupal stages of this pest on Pistacia lentiscus, one of the main tree of
the bush, and the density of the egg masses on various bush host plants.

123-127

0.00 €

 

Gypsy moth monitoring in Corsica during the latency phase (2003-2007)
Martin, J. C., Villemant, C., Bonnet, C., Jean, F., Mazet, R., Andreï-Ruiz, M. C.

Abstract: Since the years 1950, the defoliations caused by gypsy moth in Corsica are recorded in
the forest service archives. This pest sometimes induces important defoliation damages that
spread some years throughout several thousand hectares. Gypsy moth population dynamics in
Corsica is cyclic, alternating a culmination and a latency phases in a ten years’ interval. Since the
end of the last gradation in 2003, the male moth populations were monitored using pheromone
baited traps and the eggs masses numbered each year in the south of Corsica, in order to establish
an early warning method enabling to detect the beginning of a new gradation. The analysis of the
samplings made until 2007 suggests that a new gradation would probably start in the next future.

129-135

0.00 €

 

Survey of the 2006-2007 egg mass generation and the défoliation induced in 2007 by
the gypsy moth, Lymantria dispar L., in the cork oak forest of Bellif (Nefza, Tunisia)

M’nara, S., Ben Jamâa, M. L., Nouira, S.

Abstract: Mapping the defoliation caused in 2006 and 2007 by the gypsy moth Lymantria dispar
in the cork-oak forest of Bellif showed that the infestation mainly spread eastward. The local
topology and the direction of the wind, blowing predominantly from north-west, induced the
spreading of the defoliation toward the inside of the forest, on the opposite of the egg mass
distribution gradient. An average of 15 egg-masses per tree was enough to induce a complete
defoliation of the study site in 2007, notably due to a good phenological concordance between
caterpillar hatching and oak leaf bud opening. The size of the egg masses (29.25 ± 12.70mm in
average) related to a high number of eggs (560 ± 242 eggs per cluster in average) as well as the
absence of any oophagous parasioid were characteristic factors of a population in progradation.

137-145

0.00 €

 

Technical data about Gypsy Moth (Lepidoptera, Lymantriidae) pheromone bait trapping
Martin, J. C., Bonnet, C., Mazet, R., Thévenet, J.

Abstract: Capture of Gypsy Moth male using traps baited with the sexual synthesis pheromone is
a good tool for flight and population assessments if the traps are correctly used. The aim of this
study was to compare three traps models and to define their practical methods of use. The
massive captures obtained with the trap G (Icona Sp.) suggested that mass trapping could be
used to control this pest. A warning method to predict infestations using pheromone traps is also
proposed.

147-151

0.00 €

 

Biology of Tortrix viridana (Lep., Tortricidae) in cork oak forests of North-West Tunisia
Mannai, Y., Ben Jamâa, M. L., M’nara, S., Selmi, H., Nouira, S.

Abstract: The green oak moth, Tortrix viridana L., is a common defoliator of cork oak and other
oak species that is considered as a competitor of the gypsy moth, Lymantria dispar L., in North
African oak forests; its damage however usually remain casual. Significant defoliations caused by
this insect have been observed from the late 90s in different cork oak forests of north-west of
Tunisia. This study is the first performed on this pest in Tunisia; it aims at acquiring data on its
bio-ecology in two cork oak stands of the El Jouza and Bellif forests, which were infested in 2006
and 2007. The results concerned its rates of infestation, the spatial distribution of the eggs and the
importance of the different mortality factors. The characteristics of the developmental instars of
the leaf roller are also described.

153-160

0.00 €

 

Testing the use of shelters in cork oak (Quercus suber L.) reforestation
Ruiu, P. A., Pinus, A.

Abstract: The authors analyse the results obtained by using shelters in a Quercus suber L.
reforestation carried out from 2001. Two different types of shelters, with two different heights (60
and 120cm), that can be found on the market have been used for this experimentation; 5
protection modalities were tested: a) Tubex® 60cm, b) Tubex® 120cm, c) no protection (control),
d) Arboplus® 60cm, e) Arboplus® 120cm. Each year, the mortality of the seedling as well as their
diameter at collar and height were recorded. The shelters were removed in spring 2006. The
annual pluviometric data of the study period showed that the rain trend was extremely variable in
comparison to the historical average (1961-1990), with some really dry years. The data analysis
pointed out that using individual shelters led to a less important mortality level (10%) in
comparison to the control plot (30%). The higher height values have been observed in the
seedlings protected by shelters of 120cm, while the smallest values are those of the control plot.
The growth in diameter was greater in seedlings protected by Arboplus 60 and Tubex 60, while
the seedlings of the control plot showed smaller diameters. The use of the shelters, originally
employed to avoid the damages caused by animals, has proved to be an effective help to reduce
the mortality and facilitate the seedlings growth. It remains of basic importance to follow in the
future the growth of the experimental plantations, in order to assess if the good results obtained
by using individual shelters will influence the future growth of the plantation.

161-168

0.00 €

 

Artificial regeneration of cork oak (Quercus suber L.) in experimental plots,
in the Jijel region (East-Algerian coast)

Chouial, M., Benamirouche, S.

Abstract: Cork oak natural regeneration in Algeria is very problematic. To perform artificial
regeneration, the most efficient techniques must be adopted. We studied the influence of various
parameters (culture substrate, planting pot size and rootage by bands on the recovery and growth
of cork-oak seedlings. Results showed that: i) substrates made from local materials (peat and
forest humus) produced stronger seedlings than those made from imported peat; ii) larger pots
(60cm in ridge size) offered to seedlings better growth and restart conditions than smaller ones
(40-50cm in ridge size); iii) rootage by bands seemed to improve the recovery and growth of the
cork-oak seedlings.

169-173

0.00 €

 

Improvement of the Mediterranean cork-oak forest of Zerdeb using grazing flocks
Mazour, M., Boughalem, M., Benmansour, M.

Abstract: Numerous experiments aiming at protecting and improving the cork-oak forest in the
north Mediterranean region used grazing flocks to control the combustible shrub stratum. The
resuts obtained by setting-up pasture improvement trial to control grazing in The Zerdab cork-oak
forest of the Gourari region (West Algeria) showed that this environment can yield till 1 ton of
dry material/ha as pasture. Such an asset stimulates farmers to manage the environment in order
to keep up this production and simultaneously participate to erosion control and water and soil
conservation (20% of increasing infiltration and 12% of reducing erosion). Sheep farming cannot
guarantee sufficient maintenance of undergrowth clearing. But the farmer provides supplementary
mechanical clearing to maintain his forage resources. But one can wonder if the consequence of
these pasture improvement go beyond simply reducing the fire risk. The reduction of the bush
stratum and the recycling of fertilizing constituents should result in a global increase in the
fertility of the environment and a reduction of soil erosion.

175-178

0.00 €

 

Impact of the management on the vitality of cork oak
Ben Jamâa, M. L., Piazzetta, R.

Abstract: Cork oak decline is a general and worrying phenomenon in most Mediterranean
countries, but its importance varies from one country to another. This trend is very worrying in
Morocco and Portugal but less marked in Tunisia. The exact origin and the specific causes of cork
oak forest decline are very complex. It is a gradual process involving several factors
simultaneously or sequentially. The undeniable weakening of forest stands of the Mediterranean
region is linked to the interaction of biotic and abiotic factors that cause, directly or indirectly, a
progressive decrease in tree health status. This reduces the tree defense capability and creates
favorable conditions for antagonistic biotic agents such as wood-boring insects and fungal
pathogens. The present study aims at presenting the impact of wrong management on the decline
of cork oak in different Mediterranean countries.

179-186

0.00 €

 

Impact of space occupation on the conservation of the holm oak (Quercus ilex) forest
of Tessala (Sidi-Bèl-Abbès wilaya, Algeria)

Ferka-Zazou, N., Benabdeli, K., Haddouche, I., Faraoun, F.

Abstract: The impact of the space occupation on the forest ecosystem was studied in the holm
oak (Quercus ilex) forest of Telassa. This forest, characterized by a remarkable phytocenotic
diversity, suffers important uncontrolled human pressures, which constitute a direct threat for the
renewal of the living resources and the ecological balance of the zone. In order to better
understand the causes of the degradation of this ecosystem and evaluate the current state of its
space occupation, an exhaustive diagnosis was carried out including: pedological, climatic, socioeconomic
and floristic studies, and maps were drawn. The results clearly showed the impact of
bad space management on the natural ecosystem and notably an occupation in inadequacy with
the potentialities of each zone. On the basis of the data obtained, zones and sub-zones of
assignments were defined from the chart of space rational use we established with the aim at
preserving the holm oak forest.

187-191

0.00 €

 

The CORK® mark and the safeguard of cork oak forest sustainability
Varela, M. C.

Abstract: The importance of industrial products, most particularly the cork stopper, is a backbone
of cork oak forest sustainability. A depreciation of the economical value of the cork stopper
would trigger the decline of cork oak forests and all their irreplaceable environmental values.
Cork is one of the finest barks at the forest realm; however most of its uses are inconspicuous. In
spite that cork and cork products are environmentally friendly, an increasing concurrence is on
going with synthetics, especially for the stoppers. The need to defend and promote cork and all its
ecological values near the consumers drove the cork oak network from FAO/Silva Mediterranea
to promote the creation of the CORK® mark. The aim of presence of the CORK® mark logo on
wine bottles is to make the stopper “visible” and allow the consumer to identify the type of
closure. Discrimination of wines at the basis of natural/synthetic closure is an added value for
cork oak forests as well as for wines.

193-199

0.00 €

 
Add this product to your basket