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The protein and gene sequences of the cowpea Bowman-Birk type trypsin inhibitor which confers enhanced insect resistance to transgenic tobacco plants, and of cowpea trypsin/chymotrypsin inhibitors are presented. There are regions of high conservation and high divergence within the 5 leader, mature protein and 3 non-coding regions of the Bowman-Birk inhibitors and in the genes which encode them in different members of this family within the Leguminosae. The practical implications of this finding for studies on the evolution of plants and the utilization of these genes for enhancing insect resistance is discussed.  相似文献   
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Summary An efficient, aseptic method of obtaining whole broth fermentation samples was developed based on a piston-valve, a local sample loop, and an ability to drive the entire sample volume with sterile air through a sample line and into a remote tube. The configuration delivers 10-ml samples 10 m away with about 4 ml of broth wasted in the sampling process. An autosampler was enhanced and programmed to control acquisition into chilled tubes. The autosampler-based system represents a convenient way to provide frequent samples to profile intracellular and extracellular components for yeast and bacterial fermentations. A configuration to provide sampling from six fermentors with a multi-rack autosampler will be presented.  相似文献   
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Fatma Reda 《Planta》1976,130(3):265-268
Summary The soybean callus assay was used to study the effect of vernalization on the endogenous cytokinin levels of the grains of winter wheat (Triticum vulgare L.), cv. Ferto and Fema. Vernalization of the grains was carried out at 3° C in the dark for 0, 9, 18, 27, 36 and 45 days. Cytokinin activities could be detected in both the aqueous and butanol extracts of vernalized grains of both cultivars. It is suggested that flowering of winter wheat may involve changes in the levels of endogenous cytokinins during vernalization.  相似文献   
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The genus Lavandula is known for its different uses in traditional medicine. This study is interested in the chemical composition of Lavandulapedunculata subsp.atlantica (Braun‐Blanq. ) Romo as well as evaluating its antibacterial potential against multi‐resistant strains. The analysis of Lavandulaatlantica essential oil (LAEO) allows the identification of 47 components representing 93.6 % of all identified. The main constituent of LAEO was camphor (50.4 %), followed by fenchone (14.1 %) and camphene (5.6 %). The antibacterial assays revealed that LAEO was active against all the studied bacteria. A preliminary study of the relationship between certain terpenoids and antibacterial activity was also carried out in order to note the compound(s) that are responsible for LAEO's antibacterial activity. This study showed that the activity of the essential oil may be due to the presence of certain minor compounds such as carvone, considering the presence of the synergistic effect between the essential oil.  相似文献   
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The odonate larval communities in three small rivers in Penang Island were studied. More species of dragonflies were found in the Botanical Garden and Titi Teras rivers (13 and 11 respectively) of relatively similar environmental parameters. Fewer (nine) dragonfly species were collected from the Youth Park River which has a lower dissolved oxygen (DO) and a higher biological oxygen demand (BOD), conductivity and turbidity. A mixture of sand, gravel and pebble substrate of Botanical Garden River with dense growth of submerged Hydrilla, grasses and Cladias (Araceae) provided suitable habitats for the dragonflies. The sandy substrate and relatively fast flowing water of Titi Teras River was highly preferred by gomphids. In the Youth Park River, the small community of dragonfly larvae was dominated by tolerant Pseudagrion rubriceps, P. microcephalum, Orthetrum chrysis and Crocothemis servilia. Based on the larval instar distribution of Ictinogomphus decoratus and O. chrysis, very asynchronous populations of these dragonflies occurred in each river. Young larvae were continuously introduced into the populations resulting in undulating growth rate curves. The growth rates of these two species were higher in the Titi Teras River when compared to those in other rivers. Density-dependent mortality, asynchronous cannibalism and fish predation could play important roles in regulating the larval dragonfly population in these rivers.  相似文献   
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We developed a novel large-scale micropropagation pathway for date palm (Phoenix dactylifera L.) based on organogenesis. We obtained organogenic stems from shoot tip explants of the Moroccan date palm cultivar Najda, and investigated shoot proliferation from these organogenic stems in vitro on various media; Beauchesne medium (BM) and Murashige and Skoog medium (MS) at full-strength, half-strength, and one-third-strength, containing various concentrations (0, 0.25, 0.5, and 1 mg/L) of 2-naphthoxyacetic acid (NOAA) and kinetin. The optimal medium during the multiplication phase was half-strength Murashige and Skoog medium (MS/2) supplemented with 0.5 mg/L NOAA and 0.5 mg/L kinetin (23.5 morphologically superior shoots per explant, with low vitrification rates). For the shoot elongation phase, shoots were transferred to the same proliferation medium, or to MS or MS/2 media without plant growth regulators (PGRs). Shoots elongated rapidly and showed a high rate of root formation on media supplemented with PGRs. For example, on MS/2 medium containing 1 mg/L NOAA and 1 mg/L kinetin, the average shoot length was 15.1 cm, the average number of roots per shoot was 6.2, and their average length was 3.4 cm. On PGR-free media, shoots were shorter with wider and greener leaves, and had fewer roots. The plantlets were transferred to a greenhouse for acclimation. The survival rate after 2 months was related to the medium used during the elongation phase; >90 % of shoots that were cultured on PGR-free media survived, while there was a poor survival rate of shoots that had been cultured on media containing PGRs.  相似文献   
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