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591.
The fungal genera associated with larvae ofStromatium fulvum were isolated externally, internally and also those from larval galleries and exit holes. They belonged to six genera:Penicillium, Trichoderma, Helminthosporium, Aspergillus, Rhizopus andChaetomium. Based on the antagonistic effect,Trichoderma andChaetomium were used in the mortality studies. Isolation of fungi from inoculated dead larvae proved thatCheatomium spp. are non pathogenic. The genera ofTrichoderma spp.,Aspergillus spp. andPenicillium spp. were pathogenic and are recommended as biological control agents forStromatium fulvum larvae.  相似文献   
592.
A paper published byKniehase & Zoebelein (1990) describes a new laboratory method to test the side effects of pesticides on the predatory mitePhytoseiulus persimilis and criticizes the laboratory test developed by the International Working Group pesticides and beneficial organisms of the International Organization for Biological Control (IOBC), West Palaearctic Regional Section (WPRS). The present publication discusses the advantages and disadvantages of both methods, responds to the criticism and mention the overall concept of the IOBC/WPRS Working Group including semifield and field test methods.
Zusammenfassung In einer Arbeit vonKniehase undZoebelein (1990) wird ein neues Laborverfahren zur Prüfung der Nebenwirkung von Pflanzenschutzmitteln auf die RaubmilbePhytoseiulus persimilis beschrieben. Die genannten Autoren äußern sich kritisch über das seither von der Arbeitsgruppe Pflanzenschutzmittel und Nutzorganismen der International Organization for Biological Control (IOBC), West Palaearctic Regional Section (WPRS) praktizierte Verfahren. In der vorliegenden Arbeit werden die Vor- und Nachteile der beiden Prüfmethoden diskutiert. Einer Reaktion auf die Kritik folgt eine kurze Beschreibung der gesamten Konzeption der genannten Arbeitsgruppe, die auf einer Kombination aus Labor-, Halbfreiland- und Feldprüfverfahren beruht.
  相似文献   
593.
Depth distribution of soil organic carbon (SOC) fractions depends on the efficiency of agro‐technical managements. Information on depth distribution of SOC fractions mostly confined to the plow layer and scant in dry lands of Punjab, Pakistan. Therefore, a field experiment was laid out with moldboard plow (MP) (control), tine cultivator (TC), and minimum tillage (MT) as main plots, and cropping sequences fallow wheat (Triticum aestivum L.), (FW, control), mungbean (Vigna radiata L.) wheat (MW), sorghum (Sorghum bicolor L.) wheat (SW), green manure wheat (GW), and mungbean‐chickpea (MC) (Cicer arietinum L.) as sub‐plots. Treatment effects were assessed for microbial biomass carbon (MBC), potentially mineralizeable carbon (PMC), particulate organic carbon (POC), dissolved organic carbon (DOC), HCl insoluble carbon (HIC), and stratification ratio (SR) in Rawal series: Udic Haplustalf. Alfisols. The MBC concentration was the highest in MT system, at 15 to 30‐cm depth under MW and PMC concentration was highest under SW with MT at 45–60 cm. MP had higher POC in FW sequence. The highest DOC was at 0 to 15‐cm depth under MC with TC and stock of HIC was more under TC with FW sequence. The highest SR of PMC was under MT with FW at 0–15:15–30 and POC was under TC and MP with FW at depths of 0–15:45–60 cm. The highest SR for DOC was under MP with GW at 0–15:45–60 cm and HCl insoluble C was under MT with SW at 0–15:45–60. In broad‐spectrum, labile organic fractions revealed differential sensitivity, and POC stocks are also a sensitive indicator to detect the short‐management effects. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
594.
595.
Blood and seminal plasma ionic parameters are essential for monitoring health status, detecting illnesses, fish stock conservation and development of artificial propagation methods via extender improvement. In this study, comparison of blood and seminal plasma ionic parameters in beluga, Huso huso (30–45 kg, 1–2 m, n = 10), was made. The results obtained show that Na+ (82.54 ± 5.46), Cl (15.95 ± 0.72) and K+ (3.57 ± 0.15) were predominant ions in the seminal plasma (as mm ). Blood ionic values (as mm ) were determined for Na+ (110.2 ± 1.26), K+ (3.77 ± 0.081), Cl? (60.12 ± 1.5), Ca2+ (2.05 ± 0.35) and Mg2+ (1.9 ± 0.16). Results of the comparison between ionic parameters of seminal and blood plasma indicated that the concentrations of all parameters of blood plasma with the exception of K+ were significantly (p < 0.05) higher than those of seminal plasma.  相似文献   
596.
Tiaprofenic acid (Surgam) has been determined directly by using differential pulse polarography (DPP) and pH 5.5 acetate buffer as a supporting electrolyte. The differential pulse polarogram was obtained under constant amplitude pulses of 50 mV superimposed on a linearly increasing dc ramp. Peak current was measured at the peak potential of -0.990 V vs Ag/AgCl reference electrode. Under the experimental conditions used, a linear relationship between peak current and concentration was established over the range 0.5-5.0 micrograms/mL. Mean percentage recoveries for tiaprofenic acid in authentic and tablet forms were 100.27 +/- 2.25 and 99.45 +/- 1.44, respectively. The results obtained by the DPP method were compared with those of the spectrophotometric method used by the manufacturer for the analysis of tiaprofenic acid and its tablet form.  相似文献   
597.
598.
Performance of four Rosa hybrida L. cultivars (‘African Dawn’, ‘Ilios’, ‘Maroussia’ and ‘Soprano’) was evaluated. They were grown either on their own roots or grafted (stenting) onto Rosa canina L. ‘Inermis’ rootstock in a polyethylene greenhouse with hydroponics system. Parameters of plant growth and flower quality were investigated for two successive harvesting years (2005 and 2006). Results indicated that, all the cultivars were superior for most of the parameters studied when grafted onto rootstock compared to being on their own roots. Flowering stem fresh weight and diameters, flower fresh and dry weight, flower diameter and length, petal number, leaf chlorophyll content and quality index were higher in grafted plants compared to those propagated by cuttings. However, highest flowering stem length and number were observed in plants propagated by cutting, although not significant as compared with stenting method.  相似文献   
599.
Onion is one of the major vegetable crops in terms of production as well as consumption. In the current research, available onion genetic stock was evaluated to identify male-sterile lines and produce high-yielding F1 hybrids for future breeding programmes. A mitochondrial DNA-based marker was mapped and correlated with phenotypic traits to isolate male-sterile plants. Based on the floral and pollen structure, nine putative male-sterile lines were identified. On the other hand, for nuclear marker identification at Ms locus, two sets of primers were used, one for Ms dominant allele and another for sterile and maintainer plants. Results revealed that 70% of open pollinated varieties (OPVs) possess plants with sterile cytoplasm coupled with genetic sterility at Ms locus, called sterile “A” line. Approximately 20% of plants in some genotypes were identified with normal (N) cytoplasm having recessive fertility gene at Ms locus, called maintainer “B” line. Based on the present findings, “A”, “B” and “R” (restorer line), future F1 hybrid seed production systems in onion is discussed.  相似文献   
600.
Artificial keratoprostheses are indispensable for visual rehabilitation in patients with end-stage corneal blindness. This study aimed to assess the biocompatibility of polyethylene terephthalate nanofibrous mats and its potential as a novel synthetic keratoprosthesis skirt material for corneal tissue engineering. Nanofibrous mats were prepared by an electrospinning method and were first treated with the CO2 plasma to yield carboxylic groups on the surface; finally, the modified PET mat was cross linked with collagen using water-soluble carbodiimide as a coupling agent. The samples were evaluated by ATR-FTIR, scanning electron microscope (SEM), contact angle, and cell culture. The cross-linking of collagen on PET surface was confirmed by ATR-FTIR spectroscopy and SEM images The 79° difference was obtained in the contact angle analysis, obtained for the collagen-cross-linked nanofibrous mat than the non-modified nanofibrous mat. Cellular investigation showed limbal epithelial progenitor cells (LEPCs) has been better adhesion, cell growth, and proliferation of collagen-crosslinked nanofibrous samples than other samples. The bioavailability of PET fibers with covalently attached collagen was found to be identical to that of PET fibers with covalent attachment is a suitable method for enhancing the biocompatibility of scaffolds special as a good skirt in keratoprosthesis designs.  相似文献   
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