Climate Room Research Articles

Nonlinear characteristics of leakage current for flashover monitoring of ice-covered suspension insulators

This paper investigates nonlinear characteristics of leakage current (LC) for analyzing and monitoring AC flashover performance of ice-covered suspension insulators. The experiments were carried out in a cold climate room of CIGELE Laboratories according to the methods recommended by IEEE Std. 1783/2009. The maximum withstand voltage (V MW = 81 kV rms ) and minimum flashover voltage (V MF = 84 kV rms ) were obtained to reflect electrical performance of suspension insulators under a most dangerous ice type. The ice accretion process, the length, width and number of icicles associated with the appearance of partial discharges were observed and discussed to present the final formation of a relatively uniform ice layer and vertical icicles along the insulator string. This ice-covered insulator string was characterized by air gaps on the grounded-side shed space and complete ice bridging of the other shed spaces, which have significant influence on the development of arcing discharges leading to flashover. Nonlinear characteristics of LC were analyzed by using a recurrent plot (RP) technique, which graphically gives nonlinear variations of LC on RP maps as well as nonlinear indicators for quantitative prediction of the flashover. The obtained results reveal that dynamic behavior (initiation, propagation, extinguishment and re-ignition) of arcing discharges on ice-covered suspension insulators can be visually reflected by the texture transition of RP maps of LC, which correlate with different stages during the flashover process. The quantitative indicators including a recurrence rate (RR) value lower than 0.24 and a deterministic (DET) value lower than 0.965 are proposed as the predictive values to indicate the highest probability of flashover occurrence. The results obtained will be helpful to predict most hazards of ice-covered outdoor insulators; this is one of monitoring methods based on LC characteristic analysis.

A refrigerated container envelope with a PCM (Phase Change Material) layer: Experimental and theoretical investigation in a representative town in Central Italy

In this paper, a novel technology to improve the thermal performance of reefer container envelopes using a Phase Change Material (PCM) has been investigated. To that end, an external PCM layer was integrated with an insulated sandwich panel, in order to reduce and displace the heat flux phase caused by the external climatic conditions. The proposed technology was evaluated using an experimental and numerical design study. Specifically, during the experimental activities, a prototype panel was first tested inside a climatic test room and subsequently assembled on mini cold rooms and evaluated under real summer environmental conditions in Ancona (Italy). Finally, the numerical analysis was carried out using Finite Element Method (FEM) software in order to simulate a two-dimensional unsteady-state heat transfer with PCM. The calculation results were compared with the experimental values in order to validate the mathematical model, achieving a high reliability (correlation coefficient equal to 0.95).

Plant-plant interactions mediate the plastic and genotypic response of Plantago asiatica to CO2: an experiment with plant populations from naturally high CO2 areas.

The rising atmospheric CO2 concentration ([CO2]) is a ubiquitous selective force that may strongly impact species distribution and vegetation functioning. Plant-plant interactions could mediate the trajectory of vegetation responses to elevated [CO2], because some plants may benefit more from [CO2] elevation than others. The relative contribution of plastic (within the plant's lifetime) and genotypic (over several generations) responses to elevated [CO2] on plant performance was investigated and how these patterns are modified by plant-plant interactions was analysed. Plantago asiatica seeds originating from natural CO2 springs and from ambient [CO2] sites were grown in mono stands of each one of the two origins as well as mixtures of both origins. In total, 1944 plants were grown in [CO2]-controlled walk-in climate rooms, under a [CO2] of 270, 450 and 750 ppm. A model was used for upscaling from leaf to whole-plant photosynthesis and for quantifying the influence of plastic and genotypic responses. It was shown that changes in canopy photosynthesis, specific leaf area (SLA) and stomatal conductance in response to changes in growth [CO2] were mainly determined by plastic and not by genotypic responses. We further found that plants originating from high [CO2] habitats performed better in terms of whole-plant photosynthesis, biomass and leaf area, than those from ambient [CO2] habitats at elevated [CO2] only when both genotypes competed. Similarly, plants from ambient [CO2] habitats performed better at low [CO2], also only when both genotypes competed. No difference in performance was found in mono stands. The results indicate that natural selection under increasing [CO2] will be mainly driven by competitive interactions. This supports the notion that plant-plant interactions have an important influence on future vegetation functioning and species distribution. Furthermore, plant performance was mainly driven by plastic and not by genotypic responses to changes in atmospheric [CO2].

Use of infrared thermography to evaluate the influence of the of Climatic Factors in the Reproduction and Lactation of Dairy Cattle

Background: The digital infrared imaging thermography is a non-invasive imaging exam of easy performance accurately to measure temperatures of the areas of the animals body. The objective was to study the physiological variations of the surface temperature of the mammary gland, vulva, pelvis, thorax and abdomen with digital infrared imaging thermography in negative dairy cattle with California mastitis test (CMT) in different seasons, and the influence of climatic factors in these temperatures.Materials, Methods & Results: Eighteen Holstein cows, pregnant and non pregnant were used, negative for the California Mastitis Test, grazing on Urochloa decumbens pasture, receiving 2 kg of corn / animal / day, mineral mix and ad libitum water. Infrared thermography was performed every 30 days, for five months: January, February, March, April and May with thermographic camera (E40®, FLIR, Sweden) in the areas of the body: vulva, mammary gland, pelvis, abdomen and thorax. The thermal images (thermograms) were processed using the Flir Tools 2.1® program. The climatic factors: room temperature and relative humidity were monitored with globe thermometer (ITitwtg 2000®, Instrutemp, Brazil). Data were analyzed by analysis of variance and the average compared by Tukey test, with level of significance was set at (P < 0.05). For room temperature data, relative humidity, rectal temperature and for the areas of the body we used Pearson correlation (P < 0.05). For climatic factors, among the samples, room temperature and relative humidity, there was a significant difference (P < 0.05). To the skin surface temperatures of the body areas examined: vulva, pelvis, ischium, abdomen, thorax and mammary gland, among the samples, there were differences (P < 0.05) with lower temperatures of the areas in March and May samples, compared to the months of January, February and April. The average temperatures of the surfaces of the examined areas vary for the vulva between 33°C and 38°C; ischium, pelvis and abdomen between 30°C and 37°C; teats between 28°C and 37°C; Cistern of mammary quarter between 32°C and 38°C; and thorax from 31°C to 37°C. There were significant correlations between: rectal temperature x room temperature (r= 0.49; P < 0.01); Rectal temperature x relative humidity (r= -0.37; P < 0.01). To the surface temperatures of all areas of the body examined, there were significant correlations with the room temperature between (r= 0.73 and r= 0.85; P < 0.01); and between (r= - 0.57 and r= - 0.75; P < 0.05) for the relative humidity.Discussion: The animals showed no behavioral change during the thermography examination. In dairy cattle it is recommended the use of infrared thermography as a routine test to measure the temperatures of the areas of the body. Climatic factors, room temperature and relative humidity influence the rectal temperatures and the body surfaces of the cows. The areas of the body examined by infrared thermography showed different temperatures, in the same data collection, showing physiological temperature variations that assist in the clinical evaluation of each of the areas examined. The thermographic images were saved and processed easily, quickly and in a practical way, recommending the use of thermal imaging by infrared for routine as imaging test complementary to the clinical examination of the mammary gland and of the body areas in dairy cattle.

Egg parasitoids ofLobesia botrana(Den. & Schiff.) (Lepidoptera: Tortricidae) in the vineyards of Izmir and Manisa Provinces in Turkey

The study was carried out to determine egg parasitoids of Lobesia botrana (Den. & Schiff.) on Sultani Cekirdeksiz grape in Izmir and Manisa between 2009–2011. Both eggs found on grape berries in vineyards and the eggs reared in the lab and mounted onto bunches were used to determine egg parasitoids. Minimum 50 lab-reared eggs were mounted at the level of bunches in each vineyard. These eggs were re-collected after 2–4 days and maintained in the climate room for checking daily if parasitized. Parasitism rate by Trichogramma euproctidis Girault (Hymenoptera: Trichogrammatidae) on mounted L. botrana eggs was determined as 8% in conventional vineyard of Sarigol in 2009, whereas it was found 10.91% in conventional vineyard of Salihli, 5% in organic vineyard of Alasehir and 1.33% in integrated vineyard of Menemen in 2010. Natural parasitism of L. botrana eggs on berries by T. euproctidis was determined as 10% and 16% in integrated vineyard of Alasehir in 2009 and 2010, respectively. T. euproctidis parasitized 38.6% of eggs whereas T. brassicae (Bezdenko) parasitised 1.44% of eggs on the berries in 2011. T. euproctidis and T. brassicae have been determined on the eggs of L. botrana in the Aegean Region, Turkey for the first time.

Coaxial personalized ventilation system and window performance for human thermal comfort in asymmetrical environment

This paper assesses the energy performance and occupant comfort of a ceiling-mounted coaxial personalized ventilation (PV) system in presence of radiation asymmetry due to a large window for different glazing systems. Detailed 3-D computational fluid dynamics (CFD) simulations were performed to study the flow and thermal fields in the conditioned office space and evaluate longwave and diffuse shortwave radiation effect on the occupant seated directly below the PV nozzle. The CFD model was coupled to a bioheat model to predict the corresponding local and overall thermal comfort of human body parts subject to the asymmetrical environment. The CFD model is validated by conducting experiments in a climatic room equipped with the PV system and using a thermal manikin facing a hot surface. Predicted and measured values of segmental skin and air temperature at the vicinity of the thermal manikin are compared. Good agreement (less than 8% error) was found between the measured and predicted values.Extensive simulations were performed to evaluate the effect of different types of window glazing on the perceived thermal comfort under various PV operating parameters. For high performance window, the coaxial PV system achieved remarkable energy savings up to 36% when was compared to mixing ventilation (MV) system at the same level of thermal comfort and environmental outdoor conditions.

Heat stress and ACTH administration on cortisol and insulin-like growth factor I (IGF-I) levels in lactating Holstein cows

ABSTRACTPhysiological and productive responses were studied in five Holstein cows in thermal comfort (T1), stress by exogenous adrenocorticotropic hormone (ACTH) administration (T2) and heat stress (T3) to compare acute and punctual stress (ACTH) and prolonged stress (heat stress). During T1 and T2, cows were housed in a climatic-free stall barn. In T3, the animals were kept in a climatic room (air temperature of 37°C from 08:00 to 13:00 h, and of 26°C from 14:00 to 07:00 h) for 7 days. Milk yield, rectal temperature (RT), respiratory rate (RR) and blood samples were obtained before, during and after all treatments. In T1 at 08:00 h, RT and RR were below the upper critical limit. Simultaneously, cortisol and insulin growth-factor I (IGF-I) were within the normal limits. After ACTH administration (T2), cortisol significantly increased, reaching maximum levels at 60 min and returning to basal levels at 300 min. However, IGF-I was not affected. During T3, Holstein cows did not effectively dissipate their body temperature and RT, RR and cortisol significantly increased. There was a 26.6% reduction in milk production after heat stress (P < .05). Prolonged heat stress was more stressful and cows had higher levels of CORT in T3 than in T2 even before the increase in body temperature. Although the total amount of cortisol and IGF-I presented a negative and significant Pearson correlation (r = −0.79), IGF-I was not significantly influenced by heat stress or ACTH administration, and the relationship between IGF-I and heat stress remains controversial.

Assessment of Penicillium expansum and Escherichia coli transfer from poplar crates to apples

Poplar crates are widely used in contact with foodstuffs. One of the major markets for poplar crates is apple packaging. As a direct food contact material, wood is subject to European regulation n° 1935/2004, which requires no negative effect of material or packaging on foodstuffs. This study aims to quantify the transfer of Penicillium expansum conidia and Escherichia coli from poplar specimens to Golden apples. This [microorganisms-poplar-Golden apple] model was developed taking into account realistic parameters with extreme and usual conditions. Poplar specimens were artificially contaminated with P. expansum and E. coli. They were then put in contact with apples and stored in a climatic room for up to one week. Both wood specimens and apples were analyzed to assess the survival of microorganisms on wood specimens and the proportion of microorganism transfer to apples. Whereas P. expansum conidia survived but did not grow on wood specimens, E. coli mortality was observed after one hour of contact with wood. The proportion of both microorganisms transferred to apples was less than 0.25%. The impact of wood moisture content, contact time between wood and apples, and apple supply variability on the transfer levels were studied. The hygroscopic properties of wood were discussed. The low and reproducible transfer levels observed demonstrate that poplar is a safe packaging material for apples.

Effect of arsenic treatments on physiological parameters of sunflower and maize plants

The environment is contaminated with heavy metals and other toxic compounds. One of the most important toxic element is the arsenic (As).&#x0D; The objective of our study was to investigate the effect of As on fresh and dry weight of sunflower and maize in the early growth phases.&#x0D; Seedlings were grown in climate room on nutrient solution which were treated with 3, 10 and 30 mg kg-1 arsenic. The plants were treated separately with As(III) and As(V). After 14 day, changes in fresh and dry weight of maize shoots and roots were recorded. In the case of sunflower these parameters were measured after 21 day.&#x0D; The applied As(III) and As(V) decreased the fresh and dry mass of the shoots and roots of seedlings, especially at concentration 30 mg kg-1. We can draw the conclusion that the treatments of the maize and sunflower roots with arsenic had negative effects on the biomass accumulation. We found that the sunflower plants are more sensitive to arsenic toxicity than maize plants, and all data demonstrate that the As(III) is more toxic to these plants than the As(V).

Stemphylium sp., the cause of yellow leaf spot disease in sugar beet (Beta vulgaris L.) in the Netherlands

During the summer of 2007, a distinctive type of yellow leaf spot was observed for the first time in sugar beet (Beta vulgaris L.) in the Netherlands. In the following years a rapid spread over all regions of the Netherlands was reported. The infestation appears in June-August on the leaves of sugar beet and starts with small, irregular, yellow spots. Subsequently the yellow spots become necrotic from the centre of the lesion outward, with the tissue becoming brown (or brownish). The spots spread over the leaves and infest all the leaves of the plant. Due to the loss of leaves the size of the canopy declines and yield loss occurs. Research was conducted to identify the causal agent. Climate room trials with isolates obtained from infested sugar beet leaves showed that Stemphylium sp. was able to infest leaves of healthy growing sugar beet plants with brown spots, similar to the necrotic spots seen in the field. From the leaf spots in the climate room trials, Stemphylium sp. was re-isolated, according to Koch’s postulates. Thus, it was confirmed that this Stemphylium sp. is a primary pathogen for sugar beet. In field trials of fungicide efficacy a sugar yield loss of up to 42 % (a financial yield loss of 51 %) was found. Field trials show that it is hard to control this Stemphylium sp. with the fungicides registered for sugar beet in the Netherlands and efficacy of control of Stemphylium sp. differs between fungicides with active ingredients belonging to the same chemical class. In addition to sugar beet, potato (Solanum tuberosum L.), white mustard (Sinapsis alba L.), red beet (Beta vulgaris L.), spinach (Spinacia oleracea L.) and fat hen (Chenopodium album L.) were identified as hosts in an assay of plants grown and inoculated in climate rooms.

EFFECT OF ARSENIC ON DRY WEIGHT AND RELATIVE CHLOROPHYLL CONTENT IN GREENINGMAIZE AND SUNFLOWER TISSUES

Arsenic is one of the most toxic elements that can be found in the environment. Excessive uptake of arsenic may cause physiological changes in plants. The aim of the study was to investigate the effect of different arsenic treatments on relative chlorophyll content and dry weight of shoot and root of maize and sunflower in the early phases of plant development. Seedlings were grown in climatic room in nutrient solution under strictly regulated environmental conditions. The plants were exposed to 3, 10 and 30 mg kg-1arsenic, whereas there was no arsenic treatment on the control plants. We applied arsenic in the form of arsenite (NaAsO2) and arsenate (KH2AsO4), respectively. After 14 days of arsenic treatments, changes in relative chlorophyll content and dry weight of maize shoots and roots were recorded. In the case of sunflower these physiological parameters were measured after 21 day. The applied arsenic decreased the relative chlorophyll content of maize and sunflower leaves, especially at concentration of30 mg kg-1. The increasing amount of As treatment were resulted the lower weight of the experimental plants, which was more considerable in the case of the roots. The results indicate that the sunflower plants is more sensitive to arsenic toxicity than maize plants and all data demonstrate that the As(III) is more toxic to these crop plants than the As(V).

Selection of semiconductive coatings at different ambient temperatures

Anti- and de-icing techniques for the power systems have been attractive topics in recent years. Semiconductive silicone rubber coatings have been considered and applied in a few regions of China. This paper focuses on the problem of selecting semiconductive coatings under different ambient temperatures. In order to select the semiconductive coatings, the volume resistivity of the coatings doped with various carbon black concentrations was first tested. Then a series of icing/anti-icing tests on bottom-coated insulator strings were carried out in a climate room, where their antiicing performance was studied in terms of icing appearance, ice accretion weight, leakage current and surface temperature. The results show that when the ambient temperature is -2, -4 and -6 °C, the coating resistivities required to prevent ice accretion on the insulator strings tested are presented in this paper.

Personal environmental control: Effects of pre-set conditions for heating and lighting on personal settings, task performance and comfort experience

The effects of pre-set environmental conditions of temperature and lighting on the preferred personal settings, comfort experience and task performance of office workers were investigated in an individually controlled workstation. Twenty subjects performed standardized tasks at a prototype workstation with individually controlled radiant heating and lighting in a climate room. In a repeated measures design, their adjustments to pre-set values were evaluated: low and high radiant heating power, low and high direct illuminance, low and high indirect illuminance. Results showed that preferred personal settings are dependent on the initial, pre-set values of radiant heating power and illuminance. Higher pre-set values result in higher adjusted operative temperatures and higher illuminances on desk, although the differences for heating were too small to show a convincing effect. After adjustment, visual comfort was higher, but it was not dependent of the pre-set values. For thermal comfort no differences were found. Individual task performance was not negatively affected. Providing personal environmental control and the way these concepts and interfaces are designed, play a significant role in user behavior and preferences. The design and control of individually controlled workstations as well as the interaction with the general level of the office environment should be carefully considered in order to obtain maximum comfort and energy efficiency.

Quantitative histo-morphometric analysis of heat-stress-related damage in the small intestines of broiler chickens

The aim of the current research was to present a methodological approach allowing reproducible morphometric and morphological (Chiu/Park scale) analyses of the alterations in the intestines of broilers exposed to heat stress. Ross broilers were exposed over four consecutive days to a high-temperature regime in controlled climate rooms, with a day temperature of 39°C (±1°C) and a night temperature of 25°C (±1°C), respectively. A control group was kept at an ambient temperature of 25°C (±1°C) during the entire experimental period. At the end of the exposure period, the birds were sacrificed and specimens were taken of the duodenum, jejunum and ileum for histology. Blood was collected for oxidative stress analysis. Histo-morphological and morphometric analyses of the intestines indicated that the duodenum and jejunum showed more damage than the ileum. The major alterations in the control intestines were limited to the villus tips, while heat stress led to villus denudation and crypt damage. When compared with morphologically normal villi, heat-stress-associated alterations were also observed in villus height (decreased), villus breadth at base (increased) and epithelial cell area (decreased). Birds exposed to heat stress presented with an increase in glutathione peroxidase activity and a decreased antioxidant capacity. It can be concluded that the chosen model allows a reproducible quantification of heat stress effects, which is suitable for the evaluation of dietary intervention strategies to combat heat stress conditions.

Experimental approach in studying temperature effects on composite material structures realized with viscoelastic damping treatments

This paper presents a study aimed at evaluating how viscoelastic materials embedded in composite plates affect structural damping during the flight of a civil aircraft. The vibro-acoustic responses of composite fuselage structures realized with embedded viscoelastic damping treatments have been experimentally characterized at different temperature conditions. The real influence of viscoelastic materials on composite structures has been investigated, focusing the investigations on aspects still unknown, related mostly to temperature effects. In order to simulate the temperature level of commercial transport aircraft in cruise flight conditions, tests were performed using a climatic room where temperature and humidity were controlled. Vibrational tests were performed on two composite fuselage skin coupons: one treated with embedded viscoelastic damping treatments and the other one untreated. The tests were performed at temperatures of for the untreated composite fuselage structure, and and for the treated composite fuselage structure. The damping values were carried out by the impulse response decay method and the loss factor was obtained as an average of many repeated acquisitions. In order to maximize the damping effect, the best temperature interval for the treated composite fuselage skin coupon was evaluated, and the behavior for both composite fuselage structures (treated and untreated) was characterized. Thanks to the high number of tests, a statistical analysis was performed in order to validate the approach used.

Effect of the Temperature on the Nonlinear Acoustic Behavior of Reinforced Concrete Using Dynamic Acoustoelastic Method of Time Shift

During field tests, there is almost no effective way to control thermal changes in concrete structures. It is obvious that temperature fluctuations influence nonlinear acoustic behavior of concrete, which may lead to incoherent results during field investigations. The research presented herein was conducted to assess the effects of temperature changes on the nonlinear acoustic behavior of the reinforced concrete using Time Shift method. The Time Shift method, based on dynamic acoustoelastic principle, takes its roots from the coda wave interferometry method and combines it with the study of the nonlinear behavior in cementitious materials in a methodological manner that allows field investigations. Near-to-field environmental conditions were simulated in the laboratory using an automatic climatic room. The specimens were subjected to temperature changes ranging from $$-$$ 10 to 40 $$^{\circ }$$ C. Such a thermal regime is close to the thermal conditions prevailing for most concrete structures. The effect of the temperature variations was assessed in both sound and damaged concrete elements affected by alkali–silica reaction (ASR). The test-results demonstrate that the nonlinear acoustic responses of concrete depend on the temperature. However, the nonlinear parameter seems to get minimized in low temperatures ranging from $$-$$ 10 to 10 $$^{\circ }$$ C. Moreover, the state of medium (i.e. intact or damaged) can alter the sensitivity level of the nonlinear behavior to temperature variations.

Creep tests on GFRP pultruded specimens subjected to traction or shear

In this paper, experimental long-term tests on pultruded GFRP specimens are presented. Specimens have been subjected to constant traction and shear forces for about 760days. The tests have been performed under controlled temperature (20°C) and humidity (60% RH) inside a climatic room. The specimens under traction have been cut from plates and from the flanges of a wide flange GFRP pultruded beam; the specimens under shear loadings have been extracted from the web of the same beam. Moreover, some specimens have been stiffened by bonding CFRP sheets to both sides, in order to study how their introduction may reduce the specimen deformability under long term loading. Results from the unstiffened specimens have been interpreted by means of the Findley law, the reference model for creep in polymers and FRP, in terms of strains and creep coefficient. A simple model has been finally proposed to predict strains in stiffened specimens and by taking stress redistribution into account.

Responses of savanna lawn and bunch grasses to water limitation

The grass layer of African savannas consists of two main vegetation types: grazing lawns, dominated by short, mostly clonally reproducing grasses, and bunch grasslands, dominated by tall bunch grasses. This patchy distribution of vegetation types is mostly created by large herbivores, which selectively feed on the more nutritious lawn grass species. Besides grazing, herbivores trample the soil, thereby causing soil compaction, with possible consequences for water infiltration. This raises two questions: (i) is water more limiting in grazing lawns than in bunch grasslands and (ii) are lawn grasses more drought tolerant than bunch grasses? To study these questions, we compared drought conditions in both lawn and bunch grasslands in a South African savanna. Additionally, in a climate room, we compared the performance of three lawn and three bunch grass species under a control and a water limitation treatment. Thirdly, we investigated whether there are differences between lawn and bunch grasses in traits related to drought tolerance. Our results show that despite large differences in water availability in the field, lawn and bunch grasses did not differ in their growth response to drought. Drought reduced growth of both growth forms equally. However, we found strong intrinsic trait differences between growth forms, with lawn grasses having higher specific root length and relative growth rate and bunch grasses having a higher root:shoot ratio. These results suggest that after drought-induced plant death, lawn grasses might be more capable of recolonizing patches of bare soil.

Investigations on the amount of damage caused by Nezara viridula (L.) (Hemiptera: Pentatomidae) on bean pod

The study aimed to find out correlation between number of individuals and the amount of damage caused by Nezara viridula (L.) (Hemiptera: Pentatomidae) and to determine which stage of N. viridula cause the most damage on bean pod. For this purpose, 3 individual groups consisting of 10, 15 and 20 individuals were put to feed for 5 days separately in the observation cages, each of them were placed on bean plants in the manner involving a pod. At the end of the 5th day, individuals removed from the observation cages and total sucking-spot areas on the pods were calculated by measuring symptoms in square millimeter (mm). Experiments conducted in a controlled climate room conditions at temperature 25±1oC, relative humidity 45% ± 5% and photoperiod 16:8 h. By the results of experiments on the amount of damage, the fifth-stage nymphs were on the first rank with 26.11 mmsucking-spot area, followed by preoviposition females with 24.89 mmand oviposition females with 22.89 mm . After those stages, male adults and the second-stage nymphs sorted with 18.95 mmand 16.06 mm, respectively. The fourth-stage nymphs followed the third-stage nymphs with 11.39 mmcaused the least sucking-spot area. Also, a correlation was found between number of individuals and the amount of damage caused by them.

Life table parameters and predation of Orius niger Wolff (Hemiptera: Anthocoridae) feeding on two different preys

Tetranychus cinnabarinus Boisduval (Acari: Tetranychidae) ve Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae) uzerinde beslenen Orius niger (Hemiptera: Anthocoridae)’ in gelisme suresi, omru, ureme gucu ve av tuketim kapasitesi, 25±1 oC sicaklik, %65±10 orantili nem ve 16 saat aydinlik kosullari iceren iklim odasinda arastirilmistir. Erkeklerin ucuncu nimf donemi ve disilerin besinci nimf donemleri haric, T. cinnabarinus ve B. tabaci ile beslenen O. niger’ in erkek ve disi bireylerin yumurta, nimf ve toplam gelisme sureleri, besin kaynaklari arasinda onemli farklilik gostermemistir. B. tabaci ile beslenen O. niger’ in disi omur uzunlugu ve yumurtlama periyodu, T. cinnabarinus ile beslenmesine gore onemli derece uzun olmustur. B. tabaci ile beslenen O. niger’ in gunluk ve toplam biraktigi yumurta sayisi, T. cinnabarinus ile beslenmesine gore onemli derece yuksek bulunmustur. B. tabaci ile beslenen O. niger’ in net ureme gucu (R= 87.2 ♀/♀) ve kalitsal ureme yetenegi (rm = 0.120 ♀/♀/gun) daha yuksek, ortalama dol suresi (T= 37.2 gun) de daha uzun olarak saptanmistir. O. niger, artan av yogunluguna bagli olarak tuketimini arttirmis ve tuketilen T. cinnabarinus yumurtalarinin sayisi av yogunluklari arasinda onemli farklilik gostermistir. Avciya gunde 150 T. cinnabarinus yumurtasi verildiginde, bunun ortalama 89,95 adedini tukettigi gorulmustur.