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Effects of seed pretreatment by hydrogen peroxide (H 2 O 2 ) on drought tolerance in common bean plants ( Phaseolus vulgaris L.) were studied. Drought stress caused highly significant decrease in growth parameters, photosynthetic pigments, total carbohydrates and phytohormones. An increase drought stress caused highly significant increase in compatible solutes and polyamine contents as antioxidants and ABA contents in shoots of common bean plants. H 2 O 2 -pretreatment of seeds enhanced all the above parameters than the waterpretreated seeds (control) under drought condition. Results suggested that H 2 O 2 , a stress signal could trigger the activation of antioxidants in seeds which persists in the plants to alleviate the oxidative damage leading to improvements in physiological attributes for the plants growth under drought. Key words: Drought; Phaseolus vulgaris ; Common bean; Advanced effect; Hydrogen peroxide DOI: http://dx.doi.org/10.3329/bjb.v40i1.8001 Bangladesh J. Bot. 40 (1): 75-83, 2011 (June)

Orobanche aegyptiaca Pers., Orobanche cernua L. and Orobanche coelestis (Reut.) Boiss. and Reut. ex Beck are plants belong to the Orobanchaceae family in Iraq. Morphological and anatomical study of the three species is very important to to know the qualities that help us to distinguish between them. To study the morphological and anatomical traits the samples were collected from Baghdad, the southern deserts, and Kurdistan of Iraq between 2016-2018 during the flowering period (spring). The plant was preserved in special glass ampoules containing alcohol 70% for the purpose of conducting the transvere anatomy section process. The identity and morphological study as well as the anatomical study of the three species were determined by studying the anatomical transverse sections of the stem and studying the trichomes which are generally divided into two parts: Non-glandular trichomes which consist of from one or more cells, different lengths with acute or obtuse apices, and glandular trichomes which consist of a multicellular or unicellular head and stalks depended on their shape, number of cells and general characteristics as a method or Identity imprint of the plant used to differentiate among the studied species. Significant differences were observed in the general and anatomical appearance. The species Orobanche aegyptiaca Pers. is more dense in the amount of trichomes spread in all parts of the plant compared to other, O. aegyptiaca Pers. be containing 18–22 layers of parenchyma cells, the species O. cernua L. consists of 10-16 layer of parenchyma cells and the species O. coelestis (Reut.) Boiss. And Reut.exBeck consists of 20-24 layers of parenchyma cells. Morphological and anatomical study have proven its effectiveness in determining mportant characteristics in diagnosing species and distinguishing between them.

Background: Nocardia, Streptomyces and Rhodococcus are life threatening opportunistic pathogens under immunodeficiency conditions, particularly among patients infected with HIV. Rapid and accurate detection of these infections can improve immune health quality, patient management and appropriate treatment. The aim of this study was to design a novel multiplex-PCR assay for rapid diagnosis of these three organisms directly from bronchoalveolar lavage (BAL) specimens of patients infected with HIV.Methods: The genus specific primers were designed for directdetection of Nocardia, Streptomyces and Rhodococcus in a single tube multiplex PCR. This PCR specifically amplified the target genes from pure cultures. It subsequently was applied on BAL specimens of 29 HIV positive patients that had previously been culture negative for actinomycete bacteria, of which Nocardia, Streptomyces and Rhodococcus are members.Results: Of 29 respiratory clinical specimens, there were positive for Nocardia spp. and one was positive for Streptomyces spp using the multiplex PCR assay. The sequencing of the PCR products identified the species as Nocardia cyriacigeorgica (n=2), Nocardia farcinica and Streptomyces albus.Conclusion: This novel multiplex PCR assay yielded reliable results for accurate identification of Nocardia, Streptomyces and Rhodococcus from BAL while the results of bacterial culture were negative.

Sunarto, Setyaningsih R, Yanti A. 2016. Identification of denitrifying bacteria from sediments of Rawa Jombor waters, Central Java and its trophic status. Biodiversitas 17: 578-584. Pooled freshwater (lentic) is susceptible to contamination. One of pollution contributors on freshwater is the agricultural sector. One of them is the inclusion of waste in the form of organic and inorganic materials. The waste will increase the nutrient in waters causing sedimentation, eutrophication and pollution. The pollution is from nitrates derived from agricultural wastes using inorganic fertilizers. An alternative solution for the prevention and tackling of it is to utilize aquatic microorganisms namely denitrifying bacteria. These bacteria can convert nitrates into nitrogen gas (N2) in the anaerobic state so that it can handle the pollution of nitrate in water. This study aimsed to identify the denitrifying bacteria isolated from aquatic sediments of Rawa Jombor and to determine trophic status of Rawa Jombor waters. Identification of denitrifying bacteria was done through the morphology and physiology testing phase and also molecular analysis of 16S rRNA gene sequence. Based on parameters of total nitrogen, phosphor and brightness referring to the criteria of the lake trophic status attached to Ministry of Environment (PerMNLH) No. 28 2009, Rawa Jombor aquatic trophic status was analyzed. The results showed that as many as 6 denitrifying bacteria were isolated from sediments in Rawa Jombor waters, Klaten. Characteristics of bacteria colonies were translucent, round in shape, Gram-negative, rod and motile shaped cells. Based on the analysis of 16S rRNA gene sequence, all of denitrifying bacteria isolates were identified as having the highest similarity to the Shewanella genus. TmD isolate was identified as Shewanella putrefaciens, while TmE, TmG and TmI isolates were identified as Shewanella genus and TmA isolates was new species. Trophic status of Rawa Jombor aquatic was hypereutrophication.