NATURAL ENEMIES ASSOCIATED WITH MEALY PLUM APHID HYALOPTERUS PRUNI (Geoff.), (HOMOPTERA: APHIDIDAE) INFESTED APRICOT TREES, AT QALUBIA GOVERNORATE

The present work was carried out to study the population dynamics of the mealy plum aphid Hyalopterus pruni (Geoff.) and related parasitoids and predators on apricot trees, during the two successive seasons, 2003 and 2004, at Qalubia Gover-norate. The obtained data revealed that, the occurrence of H. pruni on apricot trees covered 5 months (from February to June). The mean total numbers of this aphid species per season were 1.78 (0.01-6.37) and 2.83 (0.00-10.01) individuals./leaf. The maximum numbers of H. pruni were recorded during the 2nd weeks of April, 2003 and 2004. No aphid individuals were observed during the period extended from July to September, in the two studied seasons. Four species of parasitoids; namely Aphidius matricariae Hal., Lysiphylbus sp. (1ry parasitoids) and 2 species of Alloxysta spp. (2ry parasitoids) were recorded during this study, attacking H. pruni. These parasitoid species were found during nearly three months of each season, in connection with the population density of the previous aphid species. The first para-sitoid was the highest in its numbers. The total numbers of predatory species per season were 407 and 1082 individuals, in the two studied seasons, 2003 and 2004, respectively. The maximum monthly occurrence of these predatory species was dur-ing April, 2003 (146 individuals) and April, 2004 (581 individuals), respectively. The predator Chrysoperla septempunctata L. had the highest percentages of occur-rence among other recorded predatory species (52.83 and 73.01%, respectively). In general, the parasitoid A. matricariae and the predator C. septempunctata, could be mass reared and released for controlling H. pruni on apricot trees with other availa-ble safe control methods developed in Integrated Pest Management (IPM) programs against this pest

Evaluation of sesamum gum as an excipient in matrix tablets

In developing countries modern medicines are often beyond the affordability of the majority of the population. This is due to the reliance on expensive imported raw materials despite the abundance of natural resources which could provide an equivalent or even an improved function. The aim of this study was to investigate the potential of sesamum gum (SG) extracted from the leaves of Sesamum radiatum (readily cultivated in sub-Saharan Africa) as a matrix former. Directly compressed matrix tablets were prepared from the extract and compared with similar matrices of HPMC (K4M) using theophylline as a model water soluble drug. The compaction, swelling, erosion and drug release from the matrices were studied in deionized water, 0.1 N HCl (pH 1.2) and phosphate buffer (pH 6.8) using USP apparatus II. The data from the swelling, erosion and drug release studies were also fitted into the respective mathematical models. Results showed that the matrices underwent a combination of swelling and erosion, with the swelling action being controlled by the rate of hydration in the medium. SG also controlled the release of theophylline similar to the HPMC and therefore may have use as an alternative excipient in regions where Sesamum radiatum can be easily cultivated

Ecological, physiological and genetic studies of Azospirillum

SIGLETIB: DW 1095 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

Tunable filter based on one-dimensional photonic crystal including nanocomposite material

In this work, we investigate the transmittance characteristics of one-dimensional ternary nanocomposite photonic crystals (PCs) by using the transfer matrix method. Our analysis is performed for both the transverse electric and the transverse magnetic polarized waves. We consider nanocomposite material consisting of silver nanoparticles embedded in a dielectric material. We show that the structure can block most of the visible light. In addition, we introduce a defect in the structure by two different methods. The first method is called mirror-symmetry and the second one is the conventional method where a defect layer is inserted in the middle of the PCs structure. The numerical results show that the defect mode arising in the photonic band gap can be adjusted by the incidence angle as well as the thickness of defect layer and the volume fraction. Therefore, the proposed structure is a good candidate to work as a tunable filter and a selective optical filter in the visible spectrum

The Potentiality of Marine Macro-Algae as Bio-Fertilizers to Improve the Productivity and Salt Stress Tolerance of Canola (Brassica napus L.) Plants

The present study aimed to evaluate the potentiality of three seaweeds, which belong to different algal taxa (green alga Ulva lactuca Linnaeus, brown alga Cystoseira spp., and red alga Gelidium crinale (Hare ex Turner) Gaillon) as bio-fertilizers to improve the growth and yield of canola (Brassica napus L.) plants under greenhouse conditions. Furthermore, the impact of seaweeds in alleviating the effects of salt stress (75 and 150 mM NaCl) on canola plants was also investigated. The three examined seaweeds (applied as soil amendments) successfully alleviated the harmful effects of salinity on canola plants by significantly reducing the inhibition of chlorophyll a, b, total carbohydrate accumulation, and growth promoting hormones, while increasing antioxidative compounds, such as phenols, flavonoids, anthocyanin, and osmoprotectants, including total carbohydrates and proline. Phytochemical analysis of the three examined seaweeds suggests that their stimulatory effect on growth and productivity under normal and salinity growth conditions may be linked to their constituents of a wide variety of growth promotive hormones, including indole acetic acid, indole butyric acid, gibberellic acid, cytokinins, total carbohydrates, and phenolic compounds. U. lactuca was found to be the best candidate to be used as a bio-fertilizer to improve canola growth, yield, and salt stress tolerance