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M. Toodehroosta, J. Mir-Mohammad Sadeghi,
Volume 7, Issue 2 (7-2003)
Abstract

The purpose of this study is to investigate the income distribution among the farmers of two districts of lowland and upland of Savojbolagh township of Tehran Province, Iran. The data of this study were collected by filling out questionnaires through interviews with 350 farmers who were selected by stratified random sampling. For analysis, such techniques as Gini Ratio, comparing the quintiles, and comparing means of different variables were used. The results showed that the income inequalities in the upland district were larger than in lowland. Income mean in the fifth quintile relative to other quintiles was considerably large and this fact was more serious in upland. As in income distribution, similar inequalities were observed in land distribution. The source of income of the farmers included income from agricultural activities (crops, livestock and fruit production) and from nonagricultural activities (second jobs and other incomes). Inequalities in total income in lowland and upland were mainly generated from agricultural sources of income while non-agricultural sources were less important. Inequalities in income from agricultural sources in lowland were related to livestock, fruits, and crops, and in upland to livestock, crops and fruits, respectively.
M. Chorom, C. Jafari,
Volume 7, Issue 2 (7-2003)
Abstract

Environmental pollution is one of the major problems for humans and animals. Radioactive wastes and heavy metals are important sources of pollution. Recent studies suggest that soil and geomedia have a high potential for the disposal of radioactive wastes and heavy metals. The clay minerals in geomedia can act as a barrier against radioactive wastes and heavy metals. However, enough information and experimental evidence about the mechanisms involved in the fixation of metals by clays are not available. This study aimed to show the effect of clay type on the fixation of cobalt and cadmium as affected by thermal energy. Increasing the temperature from 25 to 400°C decreased the CEC of clays in Ahwaz and Darab soils saturated with cobalt from 35.6 and 50.1 cmolc+/kg to 28.8 and 4.5, respectively. In cadmium clays, however, reductions in CEC were minimal (from 34.3 and 51.2 at 25°C to 32.5 and 47.7 cmolc+/kg at 400°C, respectively) compared to cobalt saturated clays. Consequently, the bonding characteristics change according to the size of the cations upon thermal treatment. The small cation, cobalt with an ionic radius of 0.68 Å, apparently migrates to the octahedral vacant sites and forms covalent bonds after heating at 400°C to become non-exchangable (fixed). The larger cation, Cd with an ionic radius of 0.97Å, apparently does not migrate into lattice sites on thermal treatment and remains exchangeable.
M. Sheklabadi, H. Khademi, A. H. Charkhabi,
Volume 7, Issue 2 (7-2003)
Abstract

Soil erodibility in arid regions, particularly in less developed soils, greatly depends on parent material. The objectives of this study included comparison of the potential of runoff and sediment production in soils with different parent materials and identification of the highly sensitive parent materials in Golabad watershed, 60 km northeast of Isfahan, with about 160 mm of annual precipitation and various geological formations, as one of the highly erodible watersheds in Iran. Soils formed on twelve different parent materials were selected. Rainfall simulator was run for 80 minutes on three replicates of each soil. To have an idea about the rate of runoff and sediment generation with time, runoff loaded with sediment was collected every 10 minutes using plastic containers. After measuring the volume of each runoff sample, it was dried and the amount of sediment was measured. The mechanical parameters of the applied rain were: intensity about 40 mm/hr, rain drop average diameter: 6.56 mm plot size: 1 m2 and kinetic energy of 13.7-17.2 J/m2.mm. Based on the rainfall simulation experiments, soils formed on green andesite and slightly dissected alluvium derived from both sedimentary and igneous rocks created the highest amount of runoff. They also created runoff much more rapidly as compared to other soils. In contrast, soils developed on granodiorite and moderately undulating alluvium produced the least volume of runoff. Furthermore, maximum quantity of sediment was produced from the soils occurring on green andesite and shale. The least sediment yield was observed in soils developed on granodirite and moderately undulating alluvium. Soils formed on shale created the highest sediment concentration and no significant differences were observed among other soils. Based on the results obtained, soils were ranked according to sensitivity to erosion. It is concluded that soil parent materials have a high influence on the production of runoff and sediment yield in Golabad watershed.
R. Amoo-Aghaie, A. Mostajeran, G. Emtiazi,
Volume 7, Issue 2 (7-2003)
Abstract

Azospirillum brasilense is one of the N2-fixing microorganisms which, in symbiosis with the roots of cereals and other graminae, enhances growth and development of plants. In this research, wheat seeds (Triticum aestivum) of three cultivars (Ghods, Roshan and Omid) were inoculated with Azospirillum strains (Sp7 and Dol). Inoculation increased growth parameters and yield of wheat cultivars, the effect being directly dependent on the strain-cultivar combination. Strain Sp7 induced the greatest grain yield, 1000-seed weight, number of grains per spike, root and shoot dry weight in Cv. Roshan, whereas strain Dol stimulated the best effect on these growth parameters in Cv. Ghods. The response of Cv. Omid was lower as compared to the other cultivars. Thus, it may be concluded that compatible strains are necessary for increasing yield and enhancing growth and development of wheat cultivars. These experiments also illustrated similar results regarding the effect of strains on N content of seeds. The observation of nitrogenase activity of Azospirillum strains in the In vitro experiments and the significant increases in N content in some inoculated cultivars support the hypothesis that biological nitrogen fixation by Azospirillum could be responsible for the observed beneficial effects on growth parameters. The comparison of nitrogenase activity of two strains showed that acetylene reduction rate for strain Dol was 1.5 times more than that for strain Sp7. Also strain Dol had more pronounced effects on growth parameters, yield and N content of grains than did strain Sp7. Strain Dol is a local strain whereas strain Sp7 is a Brazilian isolate thus, it may be concluded that the local isolates should be preferred to the foreign bacteria, as they are better suited to traditional cultivars, environment and soil conditions of the region.
M. Toghiani, A. Samie, A. Gheisari,
Volume 7, Issue 2 (7-2003)
Abstract

This experiment was conducted to investigate the effects of intensity of restricted early feed and increased nutrient density after restriction period on performance and compensatory growth in broilers. Two hundred and eighty-eight broiler (Lohman) chicks in a completely randomized design in a 2*3 factorial arrangement of treatments were employed. Birds were fully fed from 7 to 13d or 100% of adlibitum intake on a daily basis. The diets were diluted at 25% and 50% levels with rice hulls. After the restriction period, birds were fed with a diet, formulated to meet all their nutrient needs, according to the NRC (1994) or 10% of protein, methionine and lysine above NRC in the realimentation diet from 13 to 21d. Body weight, feed intake, daily gain and feed conversion were determined weekly and selected carcass characteristics (liver, intestine and abdominal fat pad) were measured at 49 days of age. Feed restriction significantly (P<0.01) decreased body weight gain and feed conversion during the restriction period. Birds were able to fully recover body weight depression up to 49d. The intensity of restriction had no effect on body weight, feed intake, daily gain and feed efficiency at 49d (p>0.05). Increased nutrient density had no effect on growth rate, feed intake and feed efficiency for fully-fed birds and restricted birds at 49d. The results from this experiment showed that broiler chicks may be expected to gain weight similar to chicks with fully feeding even after restricted early feed if fed with NRC diets. The effect may be due to compensatory growth.
A. Gheisari, R. Bahadoran, S. S. Tadayonfar,
Volume 7, Issue 2 (7-2003)
Abstract

In order to study the nutritive value of grades 1 and 2 wheat feed screening and macaroni wastes as energy resources, 360 21-day-old broiler chicks were divided into 36 groups of 10. In this experiment, each experimental levels of feedstuff was used at 0 (control group), 15, 30 and 45%. In addition, their apparent metabolizable energy (AMEn) was determined by Sibbald’s method. Daily feed intake of chicks fed by diets containing macaroni wastes and grade 1 wheat feed screening for 21 to 56 days of age was significantly lower than that in the control group (P<0.05). In contrast, body weight, daily weight gain and feed conversion had no significant differences during this period. However, in the total experimental period, the best feed conversion belonged to chicks fed with various levels of macaroni wastes and grade 1 wheat feed screening. Apparent metabolizable energy (AMEn) of macaroni wastes and wheat feed screening were 3700, 3270, and 2870 kcal/kg, respectively. According to the results of this experiment, it is possible to use macaroni wastes and grade 1 wheat feed screening at 45% and 30% levels in the diet of broiler chicks, respectively, without any undesirable effects on their performance.
Z. Rafiei Karahroudi, B. Hatami,
Volume 7, Issue 2 (7-2003)
Abstract

Green lacewing, Chrysoperla carnea (Steph.), is one of the important natural enemies of cotton aphid, Aphis gossypii Glover. In this study, two experiments were conducted on cucumber plant in netted cages (70*70*40 cm) in a greenhouse. In the first experiment, Chryso-bags (special net bags with 360 holes per 2.5 cm2 and 8 cm in width and 12 cm in length) were used. Seven treatments of release ratios included 1:1, 1:5, 1:10, 1:15 and 1:20 (predator: prey) and two control treatments with and without empty bags were compared. The experiment was conducted once in spring and once in autumn. In the second experiment, better release ratios were compared with two methods, Chryso-bag and sawdust as a carrier of eggs. Release ratios were 1:1 and 1:5 (predator: prey). Control treatments included only empty bag and sawdust, respectively. Results of the first experiment showed that the ratios of 1:1 and 1:5 were significantly different in spring, whereas they were not in autumn. The difference was probably due to the difference in temperature. Interaction between treatments and seasons showed that the ratios of 1:1 and 1:5 were not significantly different. In the second experiment, the release ratios of 1:1 and 1:5 in sawdust with each other and with 1:1 in Chryso-bags were not significantly different, while the ratio of 1:5 in Chryso-bag compared with 1:1 in both methods were significantly different. However, leaf necrosis was observed in the sawdust treatment.
N. Loveimi, M. Almassi,
Volume 7, Issue 2 (7-2003)
Abstract

This study aims to evaluate mechanization quality and quantity for improvement purposes. Northern Ahwaz including five districts with a total area of 286,800 hectares was selected for evaluation. The current potentials for scientific mechanization and suitable production methods in the study area were identified within the framework of a field study. In addition to a holistic study of the area and the qualitative and quantitative factors, a plain with an area of 1,100 hectares was selected for a more concentrated and specific analysis of the results. Some of the factors uniquely investigated in the study area were not able to be studied in other parts of the region. The evaluation suggests that the level of mechanization in the region is 1.1 horse power/ha, which, despite its general desirability, is low for many farming technologies in the region such that most farmers use tractors for many farming activities like plowing and furrowing. In other words, the quality of mechanization in the region (worker skills, machinery management, support services, etc.) in terms of the evaluated parameters such as lower rates of tractor efficiency (40%), steep fall in reaping wheat by combine harvesters (9.4%), and a failure in farmers’ machinery training is undesirably low, far from the mechanization level in the region. The results indicate that to increase machinery efficiency, in addition to training of farmers, efforts must be addressed at providing support services. To promote the suitable technology and the level of mechanization, appropriate technologies must be identified and the required machinery and equipment should be supplied under the supervision of research and extension centers. However, regarding the low level of innovation and also low acceptance of new technologies by local farmers, it is suggested that in addition to training and extension services, typical farms must be used and mechanization service companies should be encouraged and supported in the region to supply the technologies and machinery.
S. A. M. Mirmohammady Maibody, A. Amini, J. Khajeddin,
Volume 7, Issue 2 (7-2003)
Abstract

In this study, the potential use of halophyte grasses, Aleuropus littoralis and A. lagopoides, on soil desalinization and lowering soil salinity was investigated under glasshouse conditions. The seeds of two species were collected from Rodasht area in Isfahan and grown with four salinity treatments obtained from different types of collected soils and replicated three times. Electrical conductivities of the four soil treatments were 12.4, 29.5, 43, and 69 dS/m. The results of mean comparison showed that shoot and root dry weight, sodium contents of dry weight and Na/K ratio were significantly different in both salinized species. Both species effectively reduced soil electrical conductivity by 23 to 42.5%. This was mainly due to ion absorbtion, and consequently, from Na+, Cl-, Mg2+, Ca2+ ionic reduction. In general, considerable amounts of ionic absorbtion and total soluble salt secretion through their salt glands appeared to have the most pronounced effects on decreasing soil salinity. Regarding 50% salt excretion by these species, growing these grasses could be a possible way to decrease soil salinity by grazing or harvesting salt crusted foliage from the site.
M. J. Nazemosadat, A. R. Ghasemi,
Volume 7, Issue 3 (10-2003)
Abstract

The present study evaluates the influence of the El Ninio Southern Oscillation (ENSO) phenomenon on the cold season precipitation over Isfahan, Fars, Khuzestan, Chaharmahal-Bakhtyari, Bushehr and Kohgiluyeh-Boyerahmad provinces. The results indicate that the occurrence of La Nina events caused a 20% to 50% reduction in precipitation over Bushehr, Chaharmahal-Bakhtyari and southern Fars. The cold event did not change the total precipitation over the other parts of the region. In contrast to La Nina episodes, the occurrence of El Ninio events caused a 20% to 70% increase in rainfall in most of the study area. While the most highly wet conditions are related to the El Ninio events, the occurrence probability of the severe droughts has found to be low during such events. In association with La Nina events, the occurrence probability of severe drought was found to be low. Only in Khuzestan and southern parts of the Fars Provinces, this probability has increased to about 0.5.
S. Dehghanian, M. Ghorbani,
Volume 7, Issue 3 (10-2003)
Abstract

In this study, efficiency of apple producers in Khorasan Province was determined by a cross sectional data of 212 apple producers. Mean technical, allocative, and economic efficiencies were estimated to be around 31, 28, and 9 percent, respectively. A high potential was also detected for increasing these efficiencies. Apple producers’ age and education had positive effects and risk aversion had a negative effect on technical efficiency. Waste reduction, optimal use of inputs, introduction of technical-extension services, and apple insurance are suggested to increase efficiencies.
A. A. Ramin,
Volume 7, Issue 3 (10-2003)
Abstract

Experiments were carried out in order to micropropagate sugarcane cultivars through shoot tip and auxilliary bud culture. Rinsing of four cultivars of sugarcane, namely CP-48-103, CP-57-614, CP-69-1062, and NCO-310 in 75% alcohol for 60 seconds and their subsequent disinfection with sodium and calcium hypochloride (1.5% active material) for 15 minutes decreased a significant amount of infection of explants in the medium. The use of the Murashing and Skoog (MS) solid and liquid medium with 1 mg/l Indole Butyric Acid (IBA), 1 mg/l Kinetin, 100 mg/l mio-inositol, 1 mg/l Thiamin HCl, and 2% sucrose had significant superiority (P<0.05) to 1/2 MS solid medium. Also, to increase the multiplication in a sterile medium (In vitro), two kinds of solid and liquid MS medium, with a hormone combination of 1 mg/l IBA, 2 mg/l Kinetin and 1 mg/l 6-(benzylamino)-9-(2-tetrahydropyranyl)-9H-purine (BAP) were applied which yielded the highest amount of proliferation. The plants formed roots in Schenk and Hildebrandt (SH) medium with a hormone combination of 5 mg/l IBA and 1 mg/l Kinetin. When activate charcoal was used in the medium, a higher percentage of the plants became rooted and a larger number of adventitious roots were produced than in the dark-light or light treatments.
S. Vaseghi, M. Afyuni, H. Shariatmadari, M. Mobli,
Volume 7, Issue 3 (10-2003)
Abstract

Excessive application of sewage sludge leads to the accumulation of potentially toxic elements in soils. The objective of this greenhouse study was to examine the DTPA–extractability of Fe, Zn, Cu, Mn, Pb, Cd, Ni, and Co in relation to soil pH and to investigate the concentrations of these metals in corn (Zea mayz). The study was conducted using a factorial experiment in a completely randomized design with three replications. Sewage sludge was applied at 0, 50, 100, and 200 t/ha on four soils [Langaroud (pH= 4.8), Lahijan (pH= 5.7), Rasht (pH= 6.8), and Isfahan (pH= 7.9)]. Application of sewage sludge significantly increased DTPA-extractable Fe, Zn, Cu, Pb, Cd, and Ni in all soils. The increasing effect was in accordance with sludge level. Langaroud soil had the highest and Isfahan soil the lowest levels of DTPA-extractable metals. Application of sewage sludge increased plant growth and metals in the foliage of corn plants. The metal concentration in corn tissues also increased with decreasing soil pH. Overall, the application of sewage sludge as an organic material, particularly in acid soils, may increase availability of heavy metals, which may, in turn, result in soil pollution. Therefore, addition of sewage sludge to soils should be managed on the basis of the changes in soil heavy metal concentration.
F. Nourbakhsh, A. Jalalian, H. Shariatmadari,
Volume 7, Issue 3 (10-2003)
Abstract

Cation exchange capacity (CEC) is one of the most important chemical characteristics which influences soil quality from different aspects. At the same time, CEC is an input parameter of many computer models being applied in soil science and agriculture. Methods of CEC determination are always time-consuming and laborious. Therefore, developing a model for CEC estimation from other soil properties is essential. The objective of this study was to understand the associations between CEC (as a dependent variable) and sand, silt, clay, organic matter and pH (as independent variables). In this study 464 soil samples from A, B, and C horizons of different soils were used. Results revealed that CEC is negatively correlated with sand (r=-0.389***) and is positively correlated with organic matter (r=0.772***), clay (r= 0.391***) and silt (r= 0.233***). No significant correlation was observed between CEC and pH. Stepwise regression analysis showed that both organic matter and clay enter the model and that coefficients of determination (r2) for the multiple models are higher than those of simple linear correlations. Other parameters could not increase the r2 considerably. Correlation analysis on data from A, B, and C horizons revealed that the CEC of organic matter in different horizons are not the same. Separation of Aridisols could not increase the r2 of the model and the accuracy of the estimations. Correlation studies in acid soils showed that the contribution of organic matter in CEC is much higher than that of clays.
G. Saeidi,
Volume 7, Issue 3 (10-2003)
Abstract

In order to investigate agronomic traits and yield potential of edible-oil flax (Linum usitatissimum L.) as a second crop in Isfahan region, different genotypes were evaluated in separate experiments in early spring (April, 7) and summer (July, 16) planting dates, using a Randomized Complete Block Design with three replications. The experiments were conducted in agricultural research farm, Isfahan University of Technology in the year 2000. The results showed that summer planting considerably and significantly reduced number of seedlings per unit area, days to 50% flowering, and seed yield. However, maturity of the plants was delayed because of summer planting. According to overall average obtained for genotypes, seed yield was 1472 and 213 kg/ha in the first and second planting dates, respectively. There was a significant difference between genotypes for number of seedlings per unit area, days to 50% flowering and maturity in both planting dates. However, genotypes were significantly different for seed yield in the first planting date. Summer planting also non-significantly reduced yield/plant, capsules/plant and 100-seed weight and increased seeds/capsule. The differences between genotypes for these traits in both planting dates and for seeds/capsule in the first planting date were significant. The significant interaction between genotypes and planting dates on seeds/capsule and 100-seed weight was because of increasing or decreasing levels of these traits in some genotypes when planting date was delayed. The results of regression analysis, correlation coefficients and path analysis showed that in both planting dates, capsules/plant followed by seeds/capsule and 100-seed weight were the major components of yield/plant. Capsules/plant had the most (approximately 80%) contribution in variation of yield/plant in both planting dates. The number of plants per unit area affected yield/plant via indirect and negative effect of capsules/plant.
A. A. Gheisari, O. Saraeian, M. Toghiani, D. Asadian,
Volume 7, Issue 3 (10-2003)
Abstract

This experiment was conducted to study the effects of using cotton-seed meal on the performance and carcass yield of broiler chickens at different ages. The experiment was performed in a completely randomized design with four treatments and five replicates for each treatment. The experimental treatments included the levels of 0, 3.5, 7, and 10.5% of cotton-seed meal in diets fed to chickens at 7-21 days of age. Except for the control group, these levels for grower (21-42 d of age) was increased to 7, 14, and 21% and for finisher (42-56 d of age) to 14, 21, and 21%, respectively. For the purposes of this study, 260 day-old chicks were reared in litter until 7 days of age. On day 7, chicks were divided into 20 pens with 13 chicks in each pen. NRC (1994) recommendation was used in balancing experimental diets. The chickens were weighed weekly throughout the experimental period (7-56 d). The main observations were body gain, feed intake and feed conversion ratio. Physical analysis of carcass was done at the end of the experimental period and percentages of carcass, abdominal fat, liver, pancreas and digestive tract to live body weight were calculated. The use of cotton-seed meal and the increase of the levels through different ages had no significant effects on body weight, daily gain, feed intake, feed conversion ratio, and carcass components. Increasing the level of cotton-seed meal in the diet at 7-21 days of age had significant effects on feed intake (P<0.05) and increased it. The results of this experiment indicate that we can use cotton-seed meal at levels of 7,14, and 21% of diets, respectively, in starter, grower and finisher stages without having any adverse effects on the performance and carcass yield of broiler chickens.
S. Cheraghi Dehdezi, Sh. Dokhani, M. Shahedi,
Volume 7, Issue 3 (10-2003)
Abstract

Canning of sausage is one of the methods to extend the shelf life of sausage with lower percentage of additives such as nitrite. This method reduces transport and storgae costs, too. The present stduy was carried out in two stages. The first stage consists of preparing sausages with four different formulations in Isfahan Senobar Factory and producing canned sausage. In the second stage, physicochemical and organoleptic experiments were carried out. Canned (214409) and bottled (No. 10-67) sausages were produced and sterilized in autoclave (absolute pressure=2 atm) to give F value = 4 min. Cans and jars were filled with skinless sausage of 22 calibre and brine (2% and 25oC) at a sausage/brine ratio of 1:1. Chemical composition such as moisture, fat and protein were measured according to the standard and AOAC methods. Physical experimets including measurement of texture shear strength were performed in sausage and canned sausage over the 3-month storage period. Factorial experiments in completely randomized design was used to investigate and analyze statistical data in this study. The Duncan’s multiple range test was used to compare data averages. Moisture content increased and sausgae texture shear strength decreased in all formulations as a result of sterilization. Moisture content increased in four canned sausage formulations while protein and fat decreased (by the end of the second month of storage). Also, sausage texture shear strength was observed at this time to decrease. In organoleptic evaluations, four canned sausage formulations were not significantly different in flavor, texture, and color (P<0.01).
A. Kheiri, A. Borhani, S. M. Okhovvat, H. Eshtiaghi,
Volume 7, Issue 3 (10-2003)
Abstract

In an etiological study on stunted, nursery grown maple seedlings, a species of root-lesion nematode (Pratylenchus vulnus) and two species of fusarium (Fusarium oxysporum and F. solani) were isolated from the infected roots. Interactions between the nematode and the two fungi in a complete randomized design with six treatments and four replications were carried out under greenhouse conditions. Nematodes were surface sterilized and reared on sterilized carrot discs. Then the maple seedlings at two-leaf stage were inoculated with a population density of 40 nematodes/100 gr soil in pots. The results indicated singnificant differences between the treatments. Seven months after inoculation, the treatments with nematode alone showed a high mortality rate of about 75% along with a severe increase in population up to about 11.2 and 1266 nematodes/gr of soil and roots, respectively. In treatments with nematode and each of the two-fungus species, the deleterious effects of fungi on nematodes were observed through decrease of nematode population. It was also shown that F. oxysporum was more effective than F. solani in nematode control.
P. Norouzi, D. Cai, M. A. Malboobi, B. Yazdi Samadi,
Volume 7, Issue 3 (10-2003)
Abstract

OF2 and VAP genes, probably involved in signal transduction of sugarbeet nematode resistance, have already been cloned in bacterial vector by AFLP molecular marker and a two-hybrid system, respectively. To examine their capability to introduce resistance in sugarbeet, the genes were transferred to plant expression vectors. For this reason, OF2 gene after isolation was inserted within T-DNA of pAM194 binary vector, downstream of CaMV35S constitutive promoter and also inserted within T-DNA of modified pBin121 binary vector, downstream of HS1pro-1 gene inducing promoter (responsible for nematode resistance). VAP gene after isolation was inserted within T-DNA of pAM194 plasmid, downstream of CaMV35S constitutive promoter. Thus, three new constructs were made in which genes of signal transduction pathway were expressed to give beet cyst nematode resistance. These plasmids were separately transferred to Agrobacterium rhizogenes, strain AR15834. In the next step, petiole explants of sugarbeet were inoculated with the bacterial cells. Transformation-derived hairy roots were analyzed by GUS staining and/or PCR and were then inoculated with nematode larvae. Primary results showed partial resistance against nematode larvae in some hairy roots. As a result, this resistance can be related to OF2 and VAP genes effect.
Z. Ahmadzadeh, B. Hatami,
Volume 7, Issue 3 (10-2003)
Abstract

Greenhouse whitefly, Trialeurodes vaporariorum West. is one of the most important pests of the field crops and ornamental plants in greenhouses. Pest control is based on using chemical insecticides and biological control agents. In this study, the efficiency of the green lacewing, Chrysoperla carnea ( Steph.) with release ratios of 1:1, 1:5, 1:10, 1:15, and 1:20 (predator:prey) using eggs in chrysobag and the effect of three insecticides including Confidor (35% Sc), Permethrin (25% Ec) and Dimilin (25% Wp) at concentrations of 0.3 ml/l, 0.3 ml/l and 0.15 g/l in water, respectively, were investigated. In one experiment, the eggs of the green lacewing were released on tomato plants that were infested with 150 different nymphal instars of the pest. Control treatment included chrysobag whithout any egg. After 11 days, nymphal mortality was calculated. In insecticidal experiments, in control treatment, only water was sprayed. Both experiments were conducted in a randomized complete block design with four replications in a greenhouse with 25±5 °C, 50-60% RH and 14:10 LD period light conditions. The means of data were compared using Duncan Multiple Range Test. The results showed that the maximum nymphal mortality of 52.42% was due to the release ratio of 1:1 (predator:prey) however, this was not sufficient and did not control the pest population. The results of the chemical control also revealed that one application of Confidor caused the highest mortality about 88% that was more effective in reducing pest population compared with the release of predator eggs. Neither method had absolute control. In general, results indicated that to be more effective the two methods need to be applied more than once, and they must be combined into one or with other control methods.

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