Erster Nachweis der SchabePeriplaneta brunnea (Burm.) (Blattodea,Blattidae) in Mitteleuropa     

Ing. V. Stejskal 《Journal of pest science》1993,66(8):150-151

The first capture of the synanthropic cockroachPeriplaneta brunnea (Burm.) in the Czech Republic (Prague airport) is recorded.  相似文献   

Evaluation of isoflavone aglycon and glycoside distribution in soy plants and soybeans by fast column high-performance liquid chromatography coupled with a diode-array detector     

Klejdus B  Mikelová R  Petrlová J  Potesil D  Adam V  Stiborová M  Hodek P  Vacek J  Kizek R  Kubán V 《Journal of agricultural and food chemistry》2005,53(15):5848-5852

An ultrafast HPLC/UV-vis DAD method working at 254 nm was applied for the determination of isoflavone aglycons and glycosides (genistin, genistein, daidzein, daidzin, glycitin, glycitein, ononin, formononetin, sissotrin, and biochanin A) in roots, stems, leaves, and soy pods of soy plants and in soybeans of five varieties (Korada, Quito, Rita, OAC Erin, and OAC Vison). An Atlantis dC18 ultrafast RP chromatographic column (20 mm x 2.1 mm, 3 microm particle size) was applied for separation of the isoflavone aglycons and glycosides. A flow rate of the mobile phase (0.1% (v/v) acetic acid, pH 3.75-solvent A and methanol-solvent B) was 0.35 mL min(-1), and the column temperature was 36 degrees C. A linear gradient profile from 13 up to 22% B (v/v) from zero to 2.5 min, up to 30% B to 3.21 min, up to 35% B to 4 min, up to 40% B to 4.5 min, up to 50% B to 5.14 min, and followed by negative gradient up to 13% B to 7.71 min was used. The absolute limits of detection per sample injection (5 microL) were the highest for biochanin A (166.2 fmol) and the lowest for genistin (17.0 fmol), respectively. An accelerated solvent extraction (ASE) in combination with sonication was applied for isolation of biologically active compounds. A solid-phase extraction procedure was used to purify the extracts in the case of analysis of soy plants parts. The recoveries of 96-106% were obtained for the different concentrations of the isoflavone aglycons and glycosides and the different matrixes (overall RSDs 2-9%). The highest isoflavone concentrations were found in roots (12.5 microg g(-1) dry weight), while the amounts were about 3-1100 microg g(-1) fresh weight in different varieties of soybeans.  相似文献   

Aromatic cross-links in insect cuticle: detection by solid-state 13C and 15N NMR   总被引：2，自引：0，他引：2  

J Schaefer  K J Kramer  J R Garbow  G S Jacob  E O Stejskal  T L Hopkins  R D Speirs 《Science (New York, N.Y.)》1987,235(4793):1200-1204

Cross-polarization magic-angle-spinning nuclear magnetic resonance spectroscopy has been used to determine insect cuticle composition and cross-link structure during sclerotization or tanning. Unsclerotized cuticle from newly ecdysed pupae of the tobacco hornworm, Manduca sexta L., had a high protein content with lesser amounts of lipid and chitin. Concentrations of chitin, protein, and catechol increased substantially as dehydration and sclerotization progressed. Analysis of intact cuticle specifically labeled with carbon-13 and nitrogen-15 revealed direct covalent linkages between ring nitrogens of protein histidyl residues and ring carbons derived from the catecholamine dopamine. This carbon-nitrogen adduct was present in chitin isolated from cuticle by alkaline extraction and is probably bound covalently to chitin. These data support the hypothesis that the stiffening of insect cuticle during sclerotization results primarily from the deposition of protein and chitin polymers and their crosslinking by quinonoid derivatives of catecholamines.  相似文献   

New morphological data on the first-stage larvae of two Procamallanus species (Nematoda: Camallanidae) based on SEM studies     

Masová S  Barus V  Moravec F 《Folia parasitologica》2011,58(4):318-321

First-stage larvae of camallanid nematodes Procamallanus (Procamallanus) laeviconchus (Wedl, 1862) and Procamallanus (Procamallanus) sp. from naturally infected Distichodus niloticus (Hasselquist) and Clarias gariepinus (Burchell), respectively, from Lake Turkana, Kenya (new geographical records) are described, being for the first time studied by scanning electron microscopy. Larvae of both species are characterised by the presence of a dorsal cephalic tooth, four submedian cephalic papillae and a pair of amphids, and by the elongate tail with several terminal digit-like processes. The latter formations probably serve for the attachment of larvae to the substrate in water when the larvae attract copepod intermediate hosts by their movements; these structures, especially their numbers, may be of taxonomic importance in camallanid nematodes.  相似文献   

Webbing clothes moth,Tineola bisselliella (Hum.), causing serious feeding damage toLactuca sativa and other plant seeds     

V. Stejskal  P. Horák 《Journal of pest science》1999,72(4):87-88

The first record of a “field” infestation of stored lettuce seeds (Lactuca sativa) byTineola bisselliella (TB) is reported. The pest is able to consume almost the whole kernel ofL. sativa including the shell. The ability od TB to damage selected stored cereal, pulse and oil seeds under laboratory condition was evaluated. In maize and wheat, germ area was damaged preferably and the germination decreased considerably. TB was unable to infest and damage sound seeds of rape and beans ofPhaseolus vulgaris and soya. These findings enabled the development of a vegetarian diet for laboratory rearing of TB. The pest status and hazards resulting from cross-infestation is discassed.  相似文献   

Webbing clothes moth,Tineola bisselliella (Hum.), causing serious feeding damage toLactuca sativa and other plant seeds     

V. Stejskal  P. Horák 《Anzeiger für Sch?dlingskunde》1999,72(4):87-88

The first record of a “field” infestation of stored lettuce seeds (Lactuca sativa) byTineola bisselliella (TB) is reported. The pest is able to consume almost the whole kernel ofL. sativa including the shell. The ability od TB to damage selected stored cereal, pulse and oil seeds under laboratory condition was evaluated. In maize and wheat, germ area was damaged preferably and the germination decreased considerably. TB was unable to infest and damage sound seeds of rape and beans ofPhaseolus vulgaris and soya. These findings enabled the development of a vegetarian diet for laboratory rearing of TB. The pest status and hazards resulting from cross-infestation is discassed.  相似文献   

Size‐related oxygen consumption and ammonia excretion of Eurasian perch (Perca fluviatilis L.) reared in a recirculating system     

Vlastimil Stejskal  Jan Kouřil  Olga Valentová  Jitka Hamáčková  Tomáš Policar 《Aquaculture Research》2009,41(1):135-142

Oxygen consumption (OC) and ammonia excretion rates (AE) of perch were measured under commercial‐like conditions (temperature 23.3 °C) in both fed (F) and feed‐deprived groups (D). Measurements were taken in triplicate in six sized batches of perch ranging from 44.8 to 336.2 g. The mean daily OC was 288.3–180.6 mg O₂ kg^?1 h^?1 for group F fish ranging in size from 44.8 to 279.4 g body weight. The mean daily AE expressed as total ammonia nitrogen (TAN) was 13.8–5.2 mg TAN kg^?1 h^?1 in the same groups. Daily peaks of OC in group F perch were observed 6 h after the onset of feeding for each size group with relatively stable values up to the end of feeding. Peaks of daily AE in group F perch were observed 10 h after the onset of feeding in each size group, with a rapid decrease up to 16 h after onset. In group D, OC was 181.1–110.5 mg O₂ kg^?1 h^?1 in the weight range 57.9–336.2 g. The daily mean AE was 1.7–0.5 TAN kg^?1 h^?1 in this group. No dramatic peaks of OC and AE were observed in group D perch.  相似文献   

The effect of timing of extended photoperiod on growth and maturity of brook trout (Salvelinus fontinalis)     

Katsiaryna Lundova  Jan Matousek  Marketa Prokesova  Roman Sebesta  Tomas Policar  Vlastimil Stejskal 《Aquaculture Research》2019,50(6):1697-1704

The influence of timing of extended photoperiods on growth and maturity of brook trout was investigated in a 112‐day experiment. The fish with mean initial weight of ~192 g were reared under four light regimes: one control group with natural ambient photoperiod and three groups exposed to an 18L:6D regime initiated at days 1, 23 or 46 of the growth trial. Light‐emitting diodes, with intensity of 250–1000 lux, depending on the distance from the light source, were used for extending light periods. There was a positive effect of prolonged day length on fish growth (p < 0.05), and a delay in gonad development and sexual maturity. Significantly higher numbers of sexually mature fish were found among controls groups, regardless of sex. Survival rate was not affected by light regime. This study demonstrated that the short‐term expansion of the photo period delayed maturation and increased the growth rate of brook trout.  相似文献   

Growth,survival rate and fatty acid composition of sterlet (Acipenser ruthenus) larvae fed fatty acid‐enriched Artemia nauplii          下载免费PDF全文

Katsiaryna Lundova  Jan Kouril  Sabine Sampels  Jan Matousek  Vlastimil Stejskal 《Aquaculture Research》2018,49(10):3309-3318

We evaluated the growth and survival rate of sterlet (Acipenser ruthenus) larvae fed Artemia nauplii enriched with Olioω3 or Red Pepper commercial emulsions (BernAqua NV, Belgium). Sterlet larvae, 0.022 ± 0.002 g body weight, were randomly assigned to one of three feeding regimes with two different feeding durations. After administering live feed for 7 or 14 days, larvae were weaned onto commercial food and reared to 36 days posthatching (28 days of feeding). There were no significant differences in body weight among groups at the end of the trial. A significantly higher survival rate (p < 0.05) was observed in larvae fed Artemia enriched with Red Pepper for 14 days compared to other feeding regimes. Based on the analysis of growth parameters, we can conclude that 7 days of live feeding to be sufficient for efficient rearing of sterlet larvae. And longer duration of live feeding with use of special enrichment can be recommended for a higher survival rate.  相似文献   

Effect of temperature on growth and survival of maraena whitefish Coregonus maraena (Bloch 1779) larvae in controlled conditions          下载免费PDF全文

Roman Sebesta  Dariusz Kucharczyk  Joanna Nowosad  Mateusz Sikora  Vlastimil Stejskal 《Aquaculture Research》2018,49(9):3151-3157

This 28‐day study investigated the effect of three rearing temperatures, 11, 15 and 19°C, on survival and growth of maraena whitefish fry in a recirculating aquaculture system. Three groups of larvae in three repetitions were reared in recirculating system. Each group comprised 200 larvae. Feeding level was fixed at 500–700 Artemia sp. metanauplii per fish per day. Larvae were fed fresh live brine shrimp at 10 ml/tank every 3 hr. Significantly higher body weight (p = 0.00), total length (p = 0.00), larval yield (p = 0.00) and condition factor (p = 0.00) were obtained at 19°C compared to 15 and 11°C, as well as at 15°C compared to 11°C. Significantly higher survival (p = 0.00) was observed in larvae reared at 11 and 15°C compare to 19°C and no significant differences were observed between 11°C compared to 15°C. No significant differences in size heterogeneity among treatments were found (p = 0.46). In larviculture, the optimal assessed temperature for growth of maraena whitefish was 19°C, with highest survival observed at 11°C, at the end of this 28 days trial. The findings in this study apply to the particular study location and may not be applicable more broadly.  相似文献