Removal of viruses from Lebanese fig varieties using tissue culture and thermotherapy

Two Lebanese fig accessions of local varieties (Biadi and Aswad), infected by Fig leaf mottle-associated virus 1 (FLMaV-1), Fig leaf mottle-associated virus 2 (FLMaV-2) and Fig mosaic virus (FMV), were subjected to tissue culture and thermotherapy for producing virus-free plant material. The virus status of all progeny explants was assayed by RT-PCR using viruses-specific primers. The shoot tip culture technique was reliable for elimination of from 60 to 100% of fig viruses. However, stem cutting culture coupled with thermotherapy was the most effective for shoot regeneration (40% of reactive explants), while elimination of the three viruses was possible even though with lower rates of removal (from zero to 81%) were achieved. This study has indicated that FLMaV-2 is more susceptible to thermotherapy than FLMaV-1 and FMV

Seasonal variation of mercury concentration of ancient olive groves of Lebanon

This study investigates the seasonality of the mercury (Hg) concentration of olive tree foliage, an iconic tree of the Mediterranean basin. Hg concentrations of foliage, stems, soil surface, and litter were analyzed on a monthly basis in ancient olive trees growing in two groves in Lebanon, Bchaaleh and Kawkaba (1300 and 672 m a.s.l. respectively). A significantly lower concentration was registered in stems (∼7–9 ng g−1) in comparison to foliage (∼35–48 ng g−1) in both sites, with the highest foliage Hg concentration in late winter–early spring and the lowest in summer. It is noteworthy that olive fruits also have low Hg concentrations (∼7–11 ng g−1). The soil has the highest Hg content (∼62–129 ng g−1) likely inherited through the cumulated litter biomass (∼63–76 ng g−1). A good covariation observed between our foliage Hg time series analysis and those of atmospheric Hg concentrations available for southern Italy in the western Mediterranean basin confirms that mercury pollution can be studied through olive trees. Spring sampling is recommended if the objective is to assess the trees' susceptibility to Hg uptake. Our study draws an adequate baseline for the eastern Mediterranean and the region with similar climatic inventories on Hg vegetation uptake, in addition to being a baseline to new studies on olive trees in the Mediterranean to reconstruct regional Hg pollution concentrations in the past and present.</p

Experimental on-farm trials data of faba bean and wheat intercropping field validation in Lebanon and Morocco

This data paper describes the content of four datasets col- lected by the International Center for Agricultural Research in the Dry Areas (ICARDA) as a partner in the project “Designing InnoVative plant teams for Ecosystem Resilience and agricultural Sustainability (DIVERSify)”with the objec- tive of assessing the feasibility of faba bean-wheat mix- ture in Mediterranean environments under diverse rainfed conditions. Data was collected during the trials conducted in Kfardan-Lebanon during 2017/2018 where 40 faba bean varieties were evaluated as sole and as mixture with 2 wheat cultivars ‘Margherita’ and ‘Miki’ and during 2018/2019 where 40 faba bean varieties and one durum wheat cultivar ‘Margherita’ were evaluated under low rainfall environments. Trials were also conducted in Tal Amara-Lebanon during 2019/2020 where 20 faba bean lines and one durum wheat cultivar ‘Margherita’ were evaluated under high rainfall en- vironments and in Marchouch-Morocco during 2019/2020 where 7 faba bean lines with 3 cultivars and one durum wheat cultivar ‘Margherita’ were evaluated under extremely low rainfall environments. A detailed list of the different bi- ological traits collected for wheat and faba bean is found in the specification table in this article. The Kfardan 2018/ 2019, Tal Amara and Marchouch data is related to the conference paper “Performance of faba bean-wheat mixture under di- verse Mediterranean environments”

Phytoremediation of Lebanese polluted waters: a review of current initiatives

Water pollution is presently considered as a serious apprehension in Lebanon. Heavy contamination load of nutrients, heavy metals and organic pollutants can be highly harmful for human health and detrimental to aquatic life and ecosystems. Phytoremediation in natural and constructed wetlands using aquatic macrophytes present a sustainable plant-based technology recognized as a very efficient option in water treatment. The employment of species such as Phragmites, Sparganium, Lemna sp and other aquatic macrophytes not only helps in pollution cleanup but also conserves aquatic communities. To date, two pilot constructed wetlands, Litani River and Bcharreh have been established in Lebanon. These promising initiatives have been, however, accompanied with very limited research studies to examine the role of utilized plants and their efficiency in the remediation process. This paper presents an overview of the status of these initiatives and phytoremediation potential in Lebanon

Morphological characterization of cultivated almonds in Lebanon

Introduction. Although almond (Prunus dulcis L.) is one of the most important cultivated fruit trees in Lebanon, cultivated accessions have not yet been inventoried, and the identity of the varieties is unknown. Our study therefore aimed at assessing the genetic diversity of cultivated almonds in Lebanon using morphological characters. Materials and methods. Field surveys were performed in 2002-2003 with the aim of collecting different accessions of cultivated almond trees throughout the country. Thirty-six accessions were characterized in their cultivated habitats by using 20 qualitative and quantitative traits related mainly to the fruit, according to descriptors previously established by the International Plant Genetic Resources Institute (IPGRI). Results. A large diversity was revealed among accessions, probably due to genetic differences. Based on the qualitative studied traits, the dendogram indicated that most of the accessions were clearly distinguishable and only two cases of synonymy were observed. They have been clustered into three main groups at 0.37 of Jaccard similarity distance. Conclusion. This study needs to be completed by a DNA analysis, in order to highlight the influence of environmental conditions on the variability in the P. dulcis germplasm and to confirm the genetic distances among accessions

Newly recorded for the vascular flora of Lebanon:&amp;nbsp;Ferula biverticellata J.Thi&amp;eacute;baut (Apiaceae)

During surveys in 2020 on the Lebanese western slopes of Mount Hermon, we detected Ferula biverticellata J.Thi&amp;eacute;baut, which is new to the flora of Lebanon. The species has a distribution extending from Mount Hermon, the Golan, and the Hauran in South Syria to the Negev and Transjordan. We discuss the range of this southern Levantine element, its presence in Lebanon, and its conservation status

Newly recorded for the vascular flora of Lebanon: Ferula biverticellata J.Thiébaut (Apiaceae)

During surveys in 2020 on the Lebanese western slopes of Mount Hermon, we detected Ferula biverticellata J.Thiébaut, which is new to the flora of Lebanon. The species has a distribution extending from Mount Hermon, the Golan, and the Hauran in South Syria to the Negev and Transjordan. We discuss the range of this southern Levantine element, its presence in Lebanon, and its conservation status

Newly recorded for the vascular flora of Lebanon: Ferula biverticellata J.Thiébaut (Apiaceae)

During surveys in 2020 on the Lebanese western slopes of Mount Hermon, we detected Ferula biverticellata J.Thiébaut, which is new to the flora of Lebanon. The species has a distribution extending from Mount Hermon, the Golan, and the Hauran in South Syria to the Negev and Transjordan. We discuss the range of this southern Levantine element, its presence in Lebanon, and its conservation status

Diversity assessment of the Lebanese germplasm of pomegranate (Punica granatum L.) by morphological and chemical traits

Pomegranate (Punica granatum L.) is one of the oldest edible fruits cultivated in Lebanon but the diversity of its germplasm has not been addressed yet. The present study presents the first assessment of local pomegranates growing in the country. A set of 78 pomegranate local accessions sampled from the main production areas across the country were evaluated by using twenty-eight quantitative and ten qualitative descriptors. A large variability was revealed among accessions based on the traits studied. Principal component analysis showed that male and hermaphrodite flowers, petal width as well as fruit weight, diameter and length, in addition to juice pH and sugar/acid ratio, were the most discriminating traits. Big sized fruits up to 358.6 g were found for Lefani SL67, Lefani ML25 and Mokh El Baghl SL59 accessions while the juiciest fruits were recorded for Mokh El Baghl SL65, Hamod BH41 and Hamod B54 accessions with 75–78%. The PCA bi-plot allowed to differentiate the studied accessions in three main groups based mainly on the juice pH and sugar/acid ratio: the sweet accessions called Helou, the intermediate taste accessions named Lefani and the sour accessions generally designated as Hamod. Although preliminary, the results of this study indicate a significant diversity within the Lebanese pomegranate germplasm that should be further completed by a DNA analysis to understand the genetic structure of this germplasm with respect to conservation and breeding strategies

Evolution of almond genetic diversity and farmer practices in Lebanon: impacts of the diffusion of a graft-propagated cultivar in a traditional system based on seed-propagation

Abstract Background Under cultivation, many outcrossing fruit tree species have switched from sexual reproduction to vegetative propagation. Traditional production systems have persisted, where cultivar propagation is based on a mixed reproductive system. For millenia, almond, Prunus dulcis, has been propagated by seeds. Almond grafting remained of little importance until recently. In Lebanon, both sexual and clonal reproductions are used for almond propagation. We used 15 microsatellite markers to investigate the effect of introducing graft-propagated cultivars and associated practices, on the structure of the genetic diversity among and within the two main Lebanese cultivars. Results As expected, the sexually propagated cultivar Khachabi exhibited more genotypic and genetic diversity than the vegetatively propagated cultivar Halwani. It also exhibited lower differentiation among populations. The distribution of clones showed that propagation modes were not exclusive: farmers have introduced clonal propagation in the seed-propagated cultivar while they have maintained a diversity of genotypes within populations that were mostly graft-propagated. These practices are also important to avoid mate limitations that hamper fruit production in a self-incompatible species. ‘Khachabi’ is structured into two gene pools separated by the Lebanese mountains. As to ‘Halwani’, two different gene pools were introduced. The most ancient one shares the same geographic range as ‘Khachabi’; longtime coexistence and sexual reproduction have resulted in admixture with ‘Khachabi’. In contrast, the more recent introduction of the second gene pool in the Bekaa region followed an evolution towards more extensive clonal propagation of ‘Halwani’ limiting hybridizations. Furthermore, some pairs of geographically distant ‘Halwani’ orchards, exhibited low genetic distances, suggesting that a network of exchanges between farmers was effective on a large scale and/or that farmers brought clonal plant material from a common source. Conclusions Almond diversification in Lebanon is clearly related to the evolution of propagation practices adapted to self-incompatible cultivars. The comparison between both cultivars demonstrated the genetic effects of the introduction of a new cultivar and the associated grafting propagation practices. Our study provided information to develop a strategy for in situ conservation of cultivars and to limit gene flow from introduced material to ancient orchards