排序方式： 共有2条查询结果，搜索用时 6 毫秒
1
1.
Ines Ben Chobba Amine Elleuch Imen Ayadi Lamia Khannous Ahmed Namsi Frederique Cerqueira Noureddine Drira Néji Gharsallah Tatiana Vallaeys 《Journal of Zhejiang University. Science. B》2013,14(12):1084-1099
Endophytic flora plays a vital role in the colonization and survival of host plants, especially in harsh environments, such as arid regions. This flora may, however, contain pathogenic species responsible for various troublesome host diseases. The present study is aimed at investigating the diversity of both cultivable and non-cultivable endophytic fungal floras in the internal tissues (roots and leaves) of Tunisian date palm trees (Phoenix dactylifera). Accordingly, 13 isolates from both root and leaf samples, exhibiting distinct colony morphology, were selected from potato dextrose agar (PDA) medium and identified by a sequence match search wherein their 18S–28S internal transcribed spacer (ITS) sequences were compared to those available in public databases. These findings revealed that the cultivable root and leaf isolates fell into two groups, namely Nectriaceae and Pleosporaceae. Additionally, total DNA from palm roots and leaves was further extracted and ITS fragments were amplified. Restriction fragment length polymorphism (RFLP) analysis of the ITS from 200 fungal clones (leaves: 100; roots: 100) using HaeIII restriction enzyme revealed 13 distinct patterns that were further sequenced and led to the identification of Alternaria, Cladosporium, Davidiella (Cladosporium teleomorph), Pythium, Curvularia, and uncharacterized fungal endophytes. Both approaches confirmed that while the roots were predominantly colonized by Fusaria (members of the Nectriaceae family), the leaves were essentially colonized by Alternaria (members of the Pleosporaceae family). Overall, the findings of the present study constitute, to the authors’ knowledge, the first extensive report on the diversity of endophytic fungal flora associated with date palm trees (P. dactylifera). 相似文献
2.
Within the framework of an excavation project aimed to systematically characterize the various aspects of settlement and activities in Northern Jordan, a considerable collection of slag lumps and iron artifacts of different forms and typologies excavated from the archaeological site of Barsinia were collected. Excavations have revealed other metallurgical materials such as pottery tuyeres and furnace-like structure. Studying those finds was important because of their archaeological and technological interests. For the analytical and metallurgical study, X-ray diffraction was used to identify the mineralogical composition of samples. Inductively coupled plasma-optical emission spectrometer, energy dispersive X-ray and X-ray fluorescence spectrometer were used to determine the accurate elemental composition of these finds. Furthermore examinations by using metallographic, polarizing microscope and scanning electron microscopy were employed to diagnose the characteristic morphology and environmental effects of these archaeometallurgical finds. Microstructural investigations emphasized that iron production processes were performed locally at the archaeological site of Barsinia even if the iron ores were imported from other mining location in Jordan. Direct or “bloomer” was the main method used for smelting iron ores followed by smithing methods to locally produce iron artifacts. This, most probably, was the state of technology from the Bronze Age to the Byzantine period. To ensure the stability of these deteriorated finds for future research, required treatment and conservation processes were successfully carried out. 相似文献
1