Showing papers in "Eurasian Journal of Biosciences in 2008"

Isolation of soil Streptomyces as source antibiotics active against antibiotic-resistant bacteria

Abstract: The focus of this study was the in vitro antimicrobial activities of Streptomycetes, bacteria commonly found in soil and known antibiotic-producers. Streptomycete isolates obtained from different fields in Muðla, Turkey were evaluated for their inhibitory activities on seven microorganisms including multiple antibiotic resistant Staphylococcus aureus and Stenotrophomonas maltophilia. Fifteen Streptomycete isolates which exhibited antimicrobial activity against at least two of the test organisms were characterized by conventional methods. The results indicated that five isolates were highly active against S. aureus strains including meticillin resistant Staphylococcus aureus (MRSA). Twelve Streptomycete isolates showed anticandidal activity against Candida albicans. Ten isolates were highly active with an inhibition zone more than 30 mm in diameter. Most of the isolates inhibited growth of the Gram negative bacteria tested. Eight isolates showed antibacterial activity on S. maltophilia MU64. The inhibition zones of two were higher than 30 mm for S. maltophilia.

Induction of salt tolerance in pepper (Capsicum annuum) by 24-epibrassinolide

Abstract: In order to study the effectiveness of brassinosteroids on the amelioration of the inhibitory effect of salinity on pepper plants, a short-term experiment was conducted in greenhouse to test different concentrations of 24-epibrassinolide (0.0, 0.01, 0.05, 0.1, and 0.5 mg L -1 ) by foliar application on growth, relative water contents and chlorophyll fluorescence of pepper (Capsicum annuum cv. Beldi) plants irrigated with salt water (0.4 g L-1 NaCl). Salt decreases the different parameters of growth. However, its effects were more pronounced on the shoot than root growth. An exogenous supply of 24-epibrassinolide was found to be successful in alleviating of the inhibitory effects of salt stress on shoot growth parameters and the leaf relative water contents. However, non-significant effect of 24-epibrassinolide was observed on root growth and chlorophyll fluorescence. Out of the five concentrations, the effects of 0.5 mg L-1 proved the best under stress conditions.

The effect of AM fungi and phosphorous level on the biomass yield and ajmalicine production in Catharanthus roseus

Abstract: A field study was conducted to evaluate the effectiveness of arbuscular mycorrhizal fungi (AMF) and phosphorus levels (100, 150 and 200 kg) for increasing biomass yield and ajmalicine content in a medicinal plant (Catharanthus roseus). The plants treated with 150 and 200 kg P 2 O 5 /ha along with AMF had the maximum plant height, number of leaves, root biomass, phosphorus content, root colonization, spore count and ajmalicine content 120 days after planting when compared with the control plants. The results suggested that these treatments could be recommended for enhancing biomass and alkaloid content in C. roseus.

Soil salinity alters the morphology in Catharanthus roseus and its effects on endogenous mineral constituents

Abstract: In order to meet the ever increasing demand for medicinal plants, for the indigenous systems of medicine as well as for the pharmaceutical industry, some medicinal plants need to be cultivated commercially, but the soil salinity, which is prevalent in many parts of the world, pose serious threat to plant production. So it seems valuable, to test the important medicinal plants for their salt tolerance capacity. In the present investigation, experiments were conducted to study the effects of soil salinity on growth and mineral nutrients in Catharanthus roseus plants under pot culture. The plants were treated with different concentrations of NaCl, 25, 50, 75 and 100 mM on 30, 45, 60 and 75 days after sowing (DAS). Salinity affected all the morphological parameters and decreased the growth performance. The mineral contents (nitrogen, phosphorus, calcium, magnesium, potassium, iron, manganese and zinc) were analysed from treated as well as the control plants. All the treatments altered the mineral contents when compared to the untreated control plants but a significant change was found in 50 mM NaCl concentration, in which the levels of some minerals increased. Tissue sodium uptake was determined for all the treated plants and was found to have increased to a significant level when compared to the untreated plants.

A floristic study on miniature sacred forests at Agastheeshwaram, southern peninsular India

Abstract: The present study deals with the floristic richness of the sacred groves of Agastheeshwaram, Kanyakumari District, Tamil Nadu, India. It covers an area of ca. 2.6 ha. Altogether, 98 angiospermic species from 87 genera and 43 families were enumerated from the sacred grove. Of these species 80.6% are used as medicine, 6.12% have a timber value and 10.20% are used as minor forest produce by the local inhabitants of the study area. Some rare, endangered and endemic plants are confined to this grove only. The attendant cultural rites and religious rituals have perpetuated the status of the sacred grove, which has ensured the protection of the grove vegetation.

Studies on the efficacy of sulphate of potash (SOP) on the physiological, yield and quality parameters of banana cv. Robusta (Cavendish- AAA)

Abstract: The investigation was carried out to assess the comparative efficacy of sulphate of potash (SOP) and muriate of motash (MOP) to improve the growth, yield and quality of the Robusta banana through enhanced physiological processes. The chlorophyll content, relative water content, NRase activity, soluble protein, photosynthetic efficacy and gas exchange characters were found to be higher with 150 per cent of the recommended potassium (K) using SOP. The treatment T9 i.e. potassium application at the 150 per cent level as sulphate of potash had a higher total dry matter production, reflecting on the maximum bunch weight coupled with quality. The results clearly indicated the benefit of SOP in increasing the bunch size with better quality fruits, and hence it is recommended to integrate SOP in banana nutrition, by supplying a recommended dose of K through SOP at 2, 4, 6 and 8 months after planting.

Leaf anatomical responses of Amorphophallus campanulatus to triazoles fungicides

Abstract: In the present investigation, three different triazole compounds triadimefon (TDM), paclobutrazol (PBZ) and propiconazole (PCZ) were used to study their effects on the leaf anatomical characteristics of Amorphophallus campanulatus. The triazole treated leaves showed several variations in leaf thickness, number of stomata, stomatal pore length, width of stomata, number of spongy cells, palisade cells and number of chloroplast per palisade and spongy cells when compared to the leaves of the untreated control plants. From the results of this experiment, it can be concluded that, the triazoles appeared to show an impact on anatomical characteristics of A. campanulatus.

A preliminary study on co-digestion of ossein industry waste for methane production

Abstract: Sinews is a pasty proteinaceous by-product discharged from a primary bone clarification tank in the ossein industry, which was mixed with cattle dung in different proportions at ambient temperature. This study found that a mixture of sinews (40%) and cattle dung (60%) was more appropriate for enhanced methane yields with a high efficacy on anaerobic degradation. A maximum cumulative biogas production volume (18 L) with 71-77% methane content was obtained even with more parts of the sinews were used as a substrate. The best biogas production yield was 23.4 L biogas/Kg TVS added, revealed the suitability of the sinews mixture (40%) in the biomethanation process. In addition, the pH of each digester was not shifted to alkaline which was constantly maintained within optimal range during the course of digestion. Perhaps, this alternate strategy will be helpful for managing the odor produced from sinews during bulk storage.

A chimeric cry1X gene imparts resistance to Spodoptera litura and Helicoverpa armigera in the transgenic groundnut

Abstract: The transgenic plants of the groundnut (Arachis hypogeae) cv. TMV-2 expressing a chimeric Bt gene, cry1X, were generated using an Agrobacterium tumefaciens - mediated transformation system. A tissue culture-independent transformation method, in planta which targets the A. tumefaciens to the apical meristem was used in this study. The protocol involves in planta inoculation of the embryo axes of the germinating seeds and allowing them to grow into seedlings ex vitro. PCR analysis indicated the putative transgenic nature of the T1 generation plants. Bioassays against two major pests of the groundnut, Helicoverpa armigera and Spodoptera litura revealed several T1 plants that perform well against both the larvae. This revealed that 22% of T 1 plants harbor the transgene. The seeds of 27 T 1 plants when allowed to continued into the next generation amplified the gene of interest in most of the plants tested. Enzyme Linked-Immuno Sorbent Assay (ELISA) was used to identify the high expressing plants. The appearance of the protein band in the quickstix confirmed the expression of the chimeric Bt toxin. Southern analysis of 10 high expressing plants confirmed the integration of the transgene. These results suggest that the chimeric Bt gene was functional in the transgenic groundnut and was being expressed. The study also showed that the groundnut plants harboring the cry1X gene were resistant to two major insect defoliators of the groundnut.

An improved method of extracting genomic DNA from preserved tissues of Capsicum annuum for PCR amplification

Abstract: In this study we present a method for the extraction of genomic DNA from the different tissues of the Pepper (Capsicum annuum). A standard protocol of Dellaporta was reviewed and modified for DNA extraction from the preserved tissues of the Capsicum sample which was believed to contain high level of polysaccharides. The modified protocol employed yielded a high quality DNA and was found to be suitable for PCR and RAPD analyses. The procedure was also found to be reliable and suitable where some materials are not available and does not require phenol-chloroform extraction. The method also allowed for the preservation of plant tissues for some days from a locality where storage facilities are not accessible. We also discovered that irrespective of the sources of tissues, a good quality DNA was obtained. The quantity of DNA produced from the fleshy mesocarp tissue was more than the quantity obtained from the seeds of the same weight, this is probably due to the hard nature of the seeds and there may have been no complete breakdown of the cell wall to release the cellular contents.

Effects of nitrogen on plant-microorganism interaction

Abstract: The rhizosphere is a biologically active zone in the soil around the roots of plants. Rootmicroorganism interaction in the rhizosphere can be both beneficial to the plant, the microorganisms or to neither of them. Which factors affect the interactions between plants and microorganisms within this crowded rhizosphere? In order to investigate their interaction, contrasted tests were carried out. The plants across the nitrogen gradient were incubated with and without microorganisms. Results showed that nitrogen might play an active role in rootmicroorganism communication, and thus have an important effect on plant growth. With no nitrogen nutrient medium, microorganisms did not affect the plants growth obviously and the statistical interaction intensity of plant-microorganism approached zero. However, with a low level of nitrogen nutrient medium and an optimal nitrogen nutrient medium, plant biomass in sterile soil was more than plant biomass in non-sterile soil. The interaction intensity of plantmicroorganism appeared negative. With a high level of nitrogen nutrient medium, plants grown in a non-sterile soil had better growth than plants grown in sterile soil. The interaction intensity of plant-microorganism appeared positive. Additionally, plant growth significantly increased the microorganism biomass both in the sterile soil and non-sterile soil.

An investigation on the floristic characteristics of the Boztepe Protected Forest Area (Unye-Ordu)

Abstract: In this study, the vascular flora of the Boztepe Protected Forest Area (Unye-Ordu) which is located in the central part of the Black Sea Region was investigated in 1995-1996 and 20002001. As a result of the plant collections during the two periods a detailed floristic analysis of 355 different taxa belonging to 230 genera and 78 families was found. Distribution of the taxa according to the phytogeographical regions are follows: 38.62% Euro-Siberian, 5.30% Mediterranean, 3.09% Irano-Turanian, and 48.70% pluriregionals. The endemism rate is 1.41%.

Some geophytes identified around the Lenkoran and Lerik (Azerbaijan) region

Abstract: The basic purpose of the s u b m i t t e d w o r k was s t u d y i n g the taxonomical s t r u c t u r e , the f l o r i s t ic and phytogeographical analysis of the Lenkoran-Lerik region geophytes, introduction of perspective species to the Central Botanical Garden and their rational uses. Plant collections were carried out w i t h i n 2 0 0 4 trough 2 0 0 7 and during the t w o periods and as a result of researches for the first time the d i s t r i b u t i o n of 163 species of geophytes, belonging to 30 families and 65 genera were f o u n d . Geophytes, meeting in region, are grouped as f o l l o w s : 68 bulbous species, 61 tuber roots, 28 rhizomes and 6 corms. Among t h em 18 species are Caucasian and 17 are Azerbaijan endemic plants, with 14 geophyte species of the Mediterranean element, 29 species of Iranio-Turanian and 21 species of Hirkan elements. It has been f o u n d that 2 species are c r i t i c a l ly endangered (CR), 11 species are endangered (EN) and 20 species are vulnerable (VU), also actions for their p r o t e c t i o n and restoration are offered.

A new addition for the araneofauna of Turkey: Enoplognatha caricis (Araneae: Theridiidae)

Abstract: Enoplognatha caricis has been discovered for the first time in Turkey. The characteristic features are presented, in addition to the geographical distribution of the species.