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Summary Three species of mononchids belonging to the Prionchulus Cobb, 1916 genus, one new and two previously known species collected from natural ecosystem of Khorramabad county, Lorestan province, south west of Iran, are described. Prionchulus girchi sp. nov. is morphologically characterized by its 2.1 – 2.2 mm body length, numerous cuticular pores, slightly offset lip region, prominent labial and cephalic papillae, cephalic papillae larger than labial ones, barrel-shaped and spacious (40 – 43 × 22.5 – 24 μm) buccal cavity, weakly rounded tail tip and weakly expressed tail tip´s hyaline. In this study, P. fagi and P. muscorum were also collected and some additional data of these two species are also given.

Vast areas of Zagros Forests in Iran are mainly stocked by old oak trees have been subject to traditional land use practices which resulted in failure of oak regeneration to pass the browsing horiz...

The vast oak-dominated forests of the Zagros Mountains in southwestern Iran currently undergo large-scale dieback driven by a combination of drought and increasing incidence of charcoal disease caused by the fungal pathogens Biscogniauxia mediterranea and Obolarina persica. Here, we explore the interactive effects between drought and charcoal disease agents on the physiology and biochemistry of Quercus infectoria and Quercus libani seedlings. The combination of pathogen attack and water limitation hampered plant development, especially in Q. libani seedlings, negatively affecting growth, biomass production, photosynthetic efficiency, and leaf water potential. An increase in markers of oxidative damage together with the upregulation of the antioxidant defense revealed that drought stress and pathogen infection led to pro-oxidative conditions in both oak species, especially in Q. libani, where larger changes in malondialdehyde and hydrogen peroxide occurred. The upregulation of the antioxidant system was more prominent in Q. infectoria than in Q. libani, resulting in enhanced enzyme activity and accumulation of non-enzymatic antioxidants. Fungal infection stimulated the activity of chitinase, phenylalanine ammonia lyase and β-1,3-glucanase in Q. infectoria leaves and this response became more pronounced under water shortage. Our study highlights that drought stress greatly intensifies the effects of the charcoal disease. Moreover, our findings imply superior stress resistance of Q. infectoria conferred by a highly efficient antioxidant system, strong osmotic adjustment (through proline), and increases in resistance enzymes and secondary metabolites (phenols and flavonoids). Future investigations should focus on adult trees in their natural habitat including interactions with soil factors and other pathogens like nematodes, bacteria and other fungi. Because the present research was conducted on oak seedlings, the findings can be considered by forest nursery managers.

Thisstudy attempts to analyze the karyotype and chromosome structure in fivepopulations of Quercus libani growingin Northern Zagros. Pre-treatment, fixation, hydrolysis and staining wereconducted using root meristem and then microscopic samples were prepared andstudied. The results showed that in all studied cells of each population, thebasic chromosome number was x=12 and all of them were diploid. Karyotypeanalysis of each population was conducted separately and several indices (TL:Total Length, LA: Long Arm, SA: Short Arm, CI: Centromer Index, AR: Arm Ratio,R- value, DRL%: Difference of RelativeLength and TF%: Total Form) were determined. Karyotype formula was 12m in allstudied populations. The length of chromosomes in all populations was estimatedas 0.64-2.08 micrometers. The longest chromosome was observed in chromosomenumber 1 from population 1 and the shortest one was related to the chromosomenumber 12 from population 5. Considering of chromosomal classification, all thestudied populations were placed in class B of Stebbins which showed that there isan average symmetry in the studied karyotypes. The other estimated indices alsoshowed that in chromosomes are relatively symmetric in all populations that indicatesthis species is primitive and undeveloped., Bu çalışmanın amacı Kuzey Zagros'ta yetişen beş Quercus libani popülasyonunda karyotipve kromozom yapısını analiz etmektir. Ön muamele, fiksasyon, hidroliz veboyama, kök meristem kullanılarak yapılmıştır ve daha sonra mikroskobiknumuneler hazırlanıp, incelenmiştir. Sonuçlar, her popülasyonun çalışılan tümhücrelerinde, temel kromozom sayısının x = 12 olduğunu ve hepsinin diploidolduğunu göstermiştir. Her popülasyonun karyotip analizi ayrı ayrı gerçekleştirilmişve birkaç indeks (TL: Toplam Uzunluk, LA: Uzun Kol, SA: Kısa Kol, SI: Sentromerİndeksi, KO: Kol Oranı, R-değeri, NUF%: Nispi Uzunluk Farklılığı ve TF %:Toplam Form) belirlenmiştir. Karyotip formülü çalışılan tüm popülasyonlarda 12molarak belirlenmiştir. Tüm popülasyonlardaki kromozomların uzunluğu, 0.64-2.08mikrometre olarak hesaplanmıştır. En uzun kromozom, popülasyon 1'den 1 numaralıkromozomda ve en kısa kromozom, popülasyon 1'den kromozom 12’de gözlenmiştir.Kromozomal sınıflandırma göz önüne alındığında, çalışılan tüm popülasyonlar, incelenenkaryotiplerde bir ortalama simetri olduğunu gösteren Stebbins sınıf B'yeyerleştirilmiştir. Tahmin edilen diğer indeksler, ayrıca tüm popülasyonlarda kromozomlarınnispeten simetrik olduğunu; bu türün ilkel ve gelişmemiş olduğunu göstermiştir.

Loranthus europaeus is one of the major plant parasites threatening the fragile ecosystems of oak forests in western Iran. The mistletoe is a hemi-parasite plant which grows on forest species, especially oaks. Carbon isotope composition (δ13C) has been central to understand the behaviour of mistletoes in the field. This study investigated C and N isotope compositions in leaves of L. europaeus and of its host oaks (Quercus libani, Q. infectoria and Q. brantii) in western Iran. The goal was to assess the degree of heterotrophy, and to estimate the carbon partition between host and mistletoe and possible consequences of this phenomenon for the ecology of these hemi-parasites. Leaf samples from mistletoe and host oaks were collected in the Mirabad forests of Sardasht, Iran. Ten adult trees of each oak species, with the hemiparasite species, were sampled for determination of leaf dry weight and area, concentration in carbon and nitrogen, and contents of stable carbon and nitrogen isotopes. In all three species, we found that the levels of δ13C of the host, were higher than those of the mistletoes. Quercus infectoria, with the highest leaf mass per area and the highest carbon and nitrogen contents on a mass basis, was the oak species with the highest degree of mistletoe heterotrophy, which was negatively related with the host-mistletoe δ13C difference. Our results also showed that host and mistletoe leaf masses per area can be indicators of the heterotrophic degree of the mistletoe and an easy alternative to the determination of δ13C. In conclusion, it seems that the difference in δ13C between host and mistletoe is reduced when the host leaf mass per area, Cmass and Nmass increase. This condition relates to an increased heterotrophic degree of mistletoe.

Up to now, oribatid mite richness and diversity have not been studied in oak forests of Iran. This study aimed at determining the relationships among Oribatid mite composition, richness and diversity as well as ecological factors such as elevation, soil pH and soil moisture, tree species and stand density in oak forests in northwestern Iran. Thirty samples were randomly arranged at three elevation levels (1,100-1,300 m, 1,300-1,500 m and 1,500-1,650 m). Results indicated that 42 oribatid mite species were recorded in the study area. Nine and six species were exclusively observed in the elevations 1,100-1,300 and 1,300-1,500 m, respectively; while five mite species were commonly recorded in these two elevation categories. The study revealed that oribatid mite composition was affected by elevation gradient; however, the mean differences of species richness and diversity indices were not significant among elevation categories. Moreover, there were no significant correlations either between the densities of most frequent species of oribatid mite species and soil pH (except for Tectoribates sp.), soil moisture (except for Tectocepheus velatus), elevation, density of Quercus infectoria and density of Quercus libani in study area. Generally, variations in oribatid mite composition were more affected by physiographic factors e.g., altitude than by soil properties and oak species densities, nevertheless no environmental factors influenced oribatid mite richness and diversity in this region., Hasta ahora, la riqueza y diversidad de ácaros oribátidos no se han estudiado en bosques de robles de Irán. Este estudio tuvo como objetivo determinar las relaciones entre la composición, riqueza y diversidad de los ácaros oribátidos, así como factores ecológicos como: elevación, pH y humedad del suelo, especies de árboles y densidad del rodal en los bosques de robles en el noroeste de Irán. Se dispusieron 30 muestras de forma aleatoria en tres niveles de elevación (1.100-1.300 m, 1.300-1.500 m, 1.500-1.650 m). Se registraron 42 especies de ácaros oribátidos en el área de estudio. Se observaron nueve y seis especies exclusivamente en las elevaciones 1.100-1.300 y 1.300-1.500 m, respectivamente; mientras que cinco especies de ácaros se registraron en ambas categorías de elevación. La composición de ácaros oribátidos se vio afectada por el gradiente de elevación; sin embargo, las diferencias medias de los índices de riqueza y diversidad de especies no fueron significativas entre categorías de elevación. Tampoco hubo correlaciones significativas entre las densidades de las especies más frecuentes de ácaros oribátidos y el pH del suelo (excepto Tectoribates sp.), humedad del suelo (excepto Tectocepheus velatus), elevación, densidad de Quercus infectoria y densidad de Quercus libani. En general, las variaciones en la composición de los ácaros oribátidos se vieron más afectadas por factores fisiográficos, por ejemplo, la altitud que por las propiedades del suelo y la densidad de las especies de robles, pero ningún factor ambiental influyó en la riqueza y diversidad de los ácaros oribátidos en esta región.

This study was conducted to evaluate the chemical composition and in vitro gas production (GP) and fermentation parameters of Quercus infectoria and Quercus libani leaves following treatment with the Klebsiella pneumoniae, a tannin-degrading bacterium.This isolate was isolated on medium containing tannic acid as the sole source of carbon and energy, and identified based on 16S rRNA sequencing analysis. In both oak leaf species (i.e. Q. infectoria and Q. libani), inoculation with Klebsiella pneumoniae significantly increased (P 0·05) dry matter (DM) loss. For Q. libani, crude protein content was increased (P = 0·02) by bacterial treatment vs. control. In both oak leaves, total phenolic content and total tannins were decreased (P 0·05) as a consequence of bacterial treatment. However, bacterial processing didn't changed (P 0·05) organic matter (OM), neutral detergent fibre, acid detergent fibre or acid detergent lignin content of treated leaves. In both oak leaves the measuring parameters including GP volume, in vitro digestibility of DM and OM, estimated metabolizable energy, total volatile fatty acids, acetate, ammonia nitrogen concentration, total protozoal population and the subfamily Isotricha in treatments were higher (P 0·05) than control.It can be concluded that biological treatment of Q. infectoria and Q. libani leaves with K. pneumoniae represents a useful approach to decrease their phenolic compound content and improve their nutritive value as ruminant feed.This study demonstrated that biologically processing of tannin-containing by-products with K. pneumoniae could increase their nutritive value as ruminant feeds and increase animal productivity.

Lebanon oak is one of the important oak species in the Northern Zagros forests, west of Iran, which exposed to severe pollarding in traditional silvopastoral management. The purpose of this study was to investigate the effect of pollarding on diameter increment of Lebanon oak trees. Therefore, a less-disturbed stand (0.7 ha) and a pollarded stand (1 ha) with similar physiographical conditions were selected. Full Callipering was performed in both stands and tree species; collar diameter and crown diameter for all trees (collar diameter ≥5 cm) were recorded. Moreover, total and trunk heights were measured in Lebanon oak trees as well. To evaluate the diameter increment of Lebanon oak trees, 20 and 15 tree samples were taken in the less-disturbed and pollarded stands, respectively. A pair of increment cores per sample tree was taken 100 cm above ground level, using increment borer. In the cores, annual radial increment was measured and the annual diameter increment was calculated by doubling that value. The diameter increment distribution of Lebanon oak trees in identical age classes was determined and used for comparison. The results indicated that the difference of the mean diameter increment of Lebanon oak in the same diameter classes was significant (P

Anatomical features of the leaves of Quercus L. species are presented in this study for the first time. Leaves are bifacial and the palisade parenchyma of Q. aegilops and Q. libani is stratified into two layers, of nearly equal width, while that of Q. infectoria and Q.macranthera composed of only one layer. The cortex of both midrib and petiole is well developed with collenchyma starting just beneath the epidermis. The collenchyma of Q. aegilops is extremly thick compared with that of other species. Vascular bundles of the midrib and petiole are completely enclosed by the two pericycle layers of fibers and sclerenchyma. While the number of vascular bundles and sclerenchyma groups cupping them is 3 and 2 for midribs of Q. aegilops and Q. libani respectively, the number turns into 2 vascular elements of different appearance in their petioles. Petiole secondary vascular bundles are well developed and their sclerenchyma groups more lignified in Q. infectoria but less developed and reduced in Q. macranthera. From the results, it is concluded that the leaf blade and petiole anatomical features can provide diagnostic characters for distinguishing Quercus species of Iraq. Results also strongly support placing Q. aegilops and Q. libani in the section Cerris but Q. infectoria is more reliable in the section Mesobalanus.

Genetic diversity can play a key role in the survival of plant species. In the present study, the first data on genetic diversity and structure of nine populations in Quercus libani G. Olivier collected from northwest of Iran was provided using inter-simple sequence repeat (ISSR), inter-retrotransposon amplified polymorphism (IRAP), and start codon targeted (SCoT) markers. The proportions of polymorphic bands were 94.54, 97.96, and 90.86 %, detected by 18 ISSR, 10 IRAP, and 10 SCoT primers, respectively. The mean of Nei’s gene diversity index (H) among the populations by ISSR, IRAP, and SCoT was 0.16, 0.19, and 0.19, and Shannon diversity index (I) was 0.25, 0.29, and 0.28, respectively. Partitioning of genetic variability by analysis of molecular variance (AMOVA) according to each marker and combined data revealed that the intra-population genetic diversity was higher than among populations. Cophenetic correlation coefficient values were statistically significant between ISSR and SCoT, while it was low and insignificant between IRAP and ISSR and between IRAP and SCoT. The dendrogram obtained by each marker and combined dataset reflected geographic structure among most of the populations. Regarding the differentiation among the studied populations and the complexity in taxonomic situation within Q. libani, inter-specific crossings and/or the presence of more than one species within Q. libani is possible. This genetic characterization of Q. libani from Iran contributes to knowledge of the genetic structure of the species and is valuable to define strategies for conservation.