Insecticidal activity of the red pigment produced by a strain of the fungus Beauveria bassiana that was locally isolated from infected whitefly, Bemisia tabaci (Genn.) was assessed. The pigment is produced extracellularly and is a water-soluble. This makes it easy and simple to be recovered from fermentation broth and used in pathogenicity experiments. When applied alone to Bm. tabaci nymphs, mortality percentages of 18% was recorded. For nymphs treated with Bv. bassiana spore suspension, mortality was 60%. The best results were obtained when red pigment was combined with fungal spores with the mortality percentage being increased to up to 92%. The highest insecticidal activity against adults emerging later on from the surviving larvae of Bm. tabaci was recorded also with treatment combining pigment and fungal spores with the longest days to pupation.

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Rose is one of the most economically important ornamental crops in the world. In this study, we analyzed nine macro-and microelements in soils and petals of R. damascena Mill. cultivated in Shafa and Hada mountains. The amounts of the investigated macro-and microelements varied from one soil or petal sample to another and they were generally higher in most soil and petal samples of Shafa compared to Hada. On the other hand, the levels of the investigated elements in petal samples were not dependent on their levels in soil samples. While water extracts of the soil of farms of Shafa were slightly alkaline (pH 7.69), they were moderately alkaline (pH 8.04) in Hada farms. The amounts of oil produced by rose petals of Hada were relatively larger than those of Shafa. Amongst the five investigated constituents of the volatile oil of roses, the amounts of citronellol, geraniol, and eugenol were significantly larger in the volatile oil of rose petals of Hada compared to Shafa. This study suggests that the ecology of roses of both Hada and Shafa mountains is different and this is most likely reflected on the amount of volatile oil and its constituents. Therefore, further integrated multidisciplinary research correlating rose ecology, agronomy, and essential oil yield is highly recommended.

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Biodiversity provides a wide range of useful T HE PRESENT study aimed at surveying and identifying plant species distributed in the main valleys at high altitudes in the study area, analyzing their vegetation, depicting the prevailing plant communities and assessing the role of the environmental conditions that affect the communities. Seventy-five stands were selected to represent the the vegetation physiognomy and the accompanying environmental variations. The species abundance, life forms, chorotype, and economic uses were determined. The total number of recorded species is 165 species belonging to 128 genera and 47 families. About 69.7% of these species are perennials and 30.3% were annuals. Poaceae and Asteraceae had the highest contributions to the total flora. Chamaephytes had the highest contribution, followed by therophytes, phanerophytes, hemicryptophytes and geophytes, while hydrophytes and parasites had the lowest contribution. The economic uses of the recorded species could be arranged in descending order as follows: medicinal > grazing > fuel > human food > other uses. The mono-regional and bi-regional species were the highest, while pluri-regional and cosmopolitans were the lowest. Of the monoregionals, 36 species were Sudano-Zambezian, 17 species were Irano-Turanean and 16 species were Saharo-Arabian. The application of TWINSPAN on the cover estimates of 165 species recorded in 75 stands, led to the recognition of 8 vegetation groups (communities) at 3 rd level of classification (I: Mentha longifolia group, II: Salsola imbricata group, III: Cynodon dactylon group and IV: Pluchea dioscoridis groups on the wetland wadis, and V: Aerva javanica group, VI: Acacia gerrardii var. gerrardii group, VII: Calotropis procera group and VIII: Acacia gerrardii var. gerradii-Solanum incanum groups on multi-wadis).