نشریه روابط خاک و گیاه
پیاپی 22 (تابستان 1394)

Lettuce (Lactuca sativa L.)، as a leafy vegetable، has considerable economic benefits. Although nowadays the tendency is to grow lettuce hydroponically، growers use different nutrients solutions for lettuce production and there is not an optimal nutrients solution for lettuce production in Iran. Therefore، an experiment was carried out to introduce the optimal solution out of current solutions in the market for lettuce production. In this experiment، effects of four nutrients solutions (Hoagland and Arnon، NSHoag; Knop’s، NSKnop، England، NSUK، and University of Tabriz solution، NSUT) on two cultivars of lettuce (Siahoo and Conquistador) were assessed. The experiment was conducted as a completely randomized blocks design with four replications at Faculty of Agriculture، University of Tabriz، Iran، and traits such as total soluble solids (TSS)، panel test، percentage of leaf dry matter and leaf nitrogen، potassium، phosphorus، calcium and nitrate contents were assessed. Results showed that different nutrients solutions had significant effect on nutrients concentration and some of the qualitative characteristics of lettuce. The highest percentage of dry mater، leaf nitrogen and potassium content، were observed in Knop’s، UT and Hoagland solutions، respectively. Interaction between cultivar and nutrients solution became significant on panel test results. Hoagland and Knop’s solutions in Conquistador cultivar and England and Hoagland solutions in Siahoo cultivar showed maximum panel-test results. Nutrients solutions didn’t have significant effects on other traits. Therefore، it is concluded that Hoagland nutrients solution was the best solution for qualitative traits in lettuce production. But، it is necessary to analyze these nutrients solutions for lettuce yield and economic aspects.

To evaluate the effects of different levels of iron (Fe) (from Fe-nano-chelate and Fe-EDDHA sources) on growth parameters، concentration and absorption of Fe and some nutrients in cowpea (Vigna unguiculata) in a calcareous soil، a greenhouse experiment was conducted based on completely randomized design with three replications. Treatments consisted of four levels of Fe (0، 0. 135، 0. 270 and 0. 405 mg Fe per kg soil as Fe-nano-chelate or Fe-EDDHA). The studied soil (Fine-loamy، carbonatic، thermic، Typic Calcixerepts) had a loam texture with low available Fe content. Results showed that application of both Fe fertilizers increased shoot dry-matter yield، root dry matter yield، number of pods per plant، weight of pods and seeds per plant، grain weight per pot، shoot Fe concentration and Fe uptake by cowpea as compared to control treatment. Some of the evaluated growth parameters at all levels of Fe from Fe-nano-chelate source were higher than the Fe-EDDHA source and some were the same and had no significant difference. Application of both Fe-nano-chelate and Fe-EDDHA decreased phosphorus and manganese concentrations in shoots as compared to control treatment. Concentration of zinc and cooper in shoots was not significantly affected by the Fe level. In conclusion، lower rates of Fe-nano-chelate were required، as compared to Fe-EDDHA، to alleviate iron deficiency in cowpea grown in calcareous soils.

in order to study the effect of organic compounds and phosphate bio-fertilizer on some of the quantitative and qualitative attributes of ivy geranium (Pelarginum peltatum)، a factorial experiment، based on randomized complete blocks design، was carried out using two factors including phosphate bio-fertilizer (Barvar-2) at two levels (B0: no phosphate bio-fertilizer and B1: application of phosphate bio-fertilizer) and different substrates at 8 levels (M1: garden soil + sand، M2: garden soil + cocopeat + solid waste compost، M3: garden soil + sand + water tank soil، M4: garden soil + cocopeat + water tank soil، M5: garden soil + sand + solid waste compost، M6: garden soil + sand + solid waste compost + water tank soil، M7: sand + leaf mold + cocopeat + solid waste compost and M8: sand + tea waste compost + cocopeat + water tank soil)، with 4 replications and 256 plants. In this study، number of leaves، leaf area index، number of florets، anthocyanin content of petal، dry weight of shoots and roots and shoot phosphorus were evaluated. Results showed that both direct effects and interactions were significant on all traits. The best treatment was M8B1 (phosphate bio-fertilizer and sand + tea compost + cocopeat + water tank soil) as compared to other treatments. In general، the phosphate bio-fertilizer with M8 substrate can substitute or complete phosphate chemical-fertilizer in order to grow ivy geranium.

Improvement of plant nutrition is one of the approaches for augmenting the drought stress tolerance in plants. Due to low organic-matter content in most soils in arid and semi-arid regions of Iran، application of organic-wastes’ compost can increase water-holding capacity of the soil and improve plant nutrition. So، in this study، the interactive effects of soil moisture and municipal sewage-sludge compost were investigated on some soil chemical properties and concentration of nitrogen (N)، phosphorus (P)، potassium (K)، calcium (Ca) and magnesium (Mg) in alfalfa (Medicago sativa cv. Garehyounjeh) forage in greenhouse conditions. A factorial experiment، based on randomized complete blocks design with three replications، was conducted with two factors of soil moisture at three levels (0. 81FC-FC، 0. 56FC-0. 75FC and 0. 35FC-0. 50FC) and sewage sludge compost at four levels (0، 15، 30 and 60 g/kg of soil). The results showed that the main and interactive effects of sewage sludge compost and soil moisture on the concentration of N، P، K، Ca and Mg in alfalfa forage and electrical conductivity (EC)، pH and K concentration in soil solution were significant. As soil moisture content decreased، the concentration of N، K، Ca and Mg in alfalfa forage and the EC and K concentration of soil solution significantly increased; while the concentration of P in alfalfa forage and pH of soil solution were significantly decreased. In all the studied soil water contents in this experiment، application of 60 g sewage-sludge compost per kg of soil as compared to the 30 g/kg level، significantly decreased alfalfa growth by increasing the salinity of soil solution. Under well-watered and water-deficit stress conditions، application of 30 g sewage-sludge compost per kg of soil improved alfalfa nutrition and its forage quality.

In order to study the effects of mycorrhizal fungi on quantitative and qualitative traits of roots، shoots and flower of Lisianthus، the inoculation with two mycorrhizal fungi isolates (Glomus mosseae and G. intraradices) and their blend was experimented under different levels of phosphorus (10، 20 and 40 mg/kg soil) in a factorial trial، based on a randomized complete blocks design، under greenhouse conditions. The results indicated that inoculated Lisianthus plants had better growth and higher biomass compared to the non-mycorrhizal plants. Inoculation with arbuscular mycorrhizal fungi significantly reduced number of required days to flowering and increased flowering stem characteristics including length and number of flowering stems، number of flowers، mean flower diameter and fresh weight of flowers per plant. The results revealed that under optimum level of phosphorus، mixture of the two arbuscular mycorrhizal fungi performed better than either of them in increasing the efficiency of the studied indices.

This experiment was conducted with two genotypes of lentil (MLC321 and MLC323), two levels of calcium (0 and 5 mM Ca2+ as CaSO4) and five salinity levels (0, 4, 8, 12 and 16 dS/m) as a factorial experiment, based on completely randomized design with three replications. Seeds were sown in plastic pots and sampling of seedlings was done after 6 weeks. Results showed that in both genotypes, plant height decreased at all salinity levels (P≤ 0.05). At higher salinity levels (more than 4 dS/m), total root area and root length were decreased in both genotypes. In both genotypes, significant reduction in leaf dry weight was observed at 12 and 16 dS/m salinity levels, and root dry weight at all salinity levels (except 4 dS/m in MLC323 genotype). Salt stress increased the concentration of sodium in leaves and roots of both genotypes. Potassium and calcium concentrations of leaves increased at some salinity levels; while the concentration of these elements decreased in the roots. In MLC321 genotype, calcium treatment significantly (P≤ 0.05) increased plant height and leaf area and dry weight at 4 dS/m salinity level. In MLC323 genotype, calcium treatment significantly (P≤ 0.05) reduced sodium concentration of roots at 8 dS/m and leaf potassium at 4 dS/m salinity level. In both genotypes, calcium treatment at high levels of salinity (12 and 16 dS/m) was unable to offset the negative effects of salinity. It seems that using calcium sulfate, due to its role in osmoregulation, can limit the damages caused by low salinity (4 dS/m) in lentil.

Development of training courses for producers could create a basis for management of sustainable development in greenhouse productions. The main purpose of this study was to investigate the effect of training courses on improving managerial skills of greenhouse owners. This study used a descriptive and correlation survey method in which the population of the study included greenhouse owners in South-Baraan district، Isfahan Township. The considered population consisted of 180 greenhouses. According to Cochran''s formula، the sample size for this population was estimated at 72. Sampling was performed randomly. The research tool was a questionnaire، which its validity was approved by using some university professors’ opinions. Reliability of the questionnaire was determined by Cronbach’s Alpha coefficient (0. 88). Data were analyzed using SPSS software. The results showed that from the point of view of greenhouse owners، technical educations had the greatest impact on improving their management skills. Results of multiple regression (stepwise method) showed that training courses such as: appropriate methods of irrigation، appropriate methods of harvest product، membership in organizations and appropriate methods of use the formal credit had positive role in improving the managerial skills of greenhouse owners and explain 50. 03% of changes in dependent variable.

The aim of this study was to evaluate the factors affecting the attitude of cucumber and tomato greenhouse farmers toward production of healthy crops in Isfahan County. Data were collected on a sample of 110 farmers through face-to-face interviews based on a comprehensive structured questionnaire. Validity and reliability of the questionnaire was initially evaluated on a pre-test study respectively by using Kaiser-Meyer-Olkin (KMO) criteria and Cronbach’s alpha coefficient. Factors influencing farmers'' attitudes were assessed by using linear regression model and ordinary least squares (OLS) estimation. Results indicated that most greenhouse farmers (85%) had moderate and positive attitudes about production of healthy crops and only 15% had negative attitudes. In addition، economic and technical supports by the government، awareness of the related organizations، marketing and media have a positive effect on the farmers'' attitudes toward production of healthy crops and there is a less positive attitude with increasing the age of farmers.

Petroleum hydrocarbons (PHs) are one of the most important soil contaminants. Presence of these compounds in soil may cause some stresses to plants and make the growth conditions unfavorable. Thus، for landscaping in the contaminated areas، tolerant plants to these stresses are needed. The aim of this research was to determine morphophysiological characteristics of two native and non-native bermudagrass species in a soil with 0، 2. 1، 3. 87 and 12. 25 percent by weight PHs: soil. A factorial experiment، based on randomized complete blocks design with three replications، was performed in research greenhouse of College of Agriculture، Isfahan University of Technology، Isfahan، Iran. Results showed that application of 2. 1% PHs to soil significantly reduced color and density of bermudagrasses (3. 3% and 5%، respectively)، and the growth of native and non-native species was reduced by 31. 1% and 7. 3%، respectively. Relative water content and chlorophyll content were significantly decreased and proline content was increased، when soil pollutant content by PHs was increased. Also، the increase in contaminants content up to 2. 1% increased catalase activity. But، higher rates of contamination reduced its activity، as compared to control. Conclusively، both bermudagrass species had acceptable turf quality and therefore could be recommended to be used in PHs-polluted soils; although quality and growth of non-native bermudagrass was better than the native one.

This research was performed to study the effect of direct planting and transplanting of potato minituber on its yield and yield components. The experiment was designed as a randomized complete blocks with nine treatments and three replications. Treatments were one direct and eight indirect planting. In order to prepare the nursery، two types of pots (peat and nylon) and four types of substrates including sand + peat moss (1:1)، sand + Kimiya organic fertilizer (1:1)، sand + vermicompost (1:1) and sand + farm soil (1:1) were used. Results showed that there was significant difference in regard to mean yield per plant، mean wet weight of tuber، number of tubers smaller and greater than 80 g، percent dry weight of tuber، biologic yield، starch percentage and nitrate content of tubers. The highest mean tuber yield per plant، number of tubers greater than 80 gr and biologic yield belonged to plants in nylon pots with substrate of sand + Kimiya organic fertilizer. The highest percentage of starch and tuber dry matter belonged to plants in peat pots with substrate of sand + soil. The highest mean wet weight of tubers belonged to nylon pots with substrate of sand + peat moss. The highest number of tubers lower than 80 g and the highest nitrate content was obtained by direct planting. The sand+ Kimiya organic fertilizer، which provides the necessary elements for plant growth، with more yield and number of marketable tubers، could be the best substrate as compared to other substrates used in this experiment.

One of the effective environmental factors on plant growth is proper lighting condition during its growth period. Planting bedding varieties of dwarf Lisianthus is developing due to its various colors and long flowering-period. This study was conducted to investigate the effect of shade and different polyethylene covers on quantitative and qualitative characteristics of dwarf Lisianthus (Eustoma grandiflorum) cv. Matador، as a template plant which spends its primary growth stage under greenhouse conditions. Treatments included polyethylene plastic with different percents of UV-stabilizer additive (0، 3، 5 and 8%)، 50% shading cover، and open space (control). Results showed that the highest number of flowering stems، open flowers and flowering stem diameter were observed by 8% UV- stabilizer (20% shade)، and had significant difference with 50% shade treatment. Maximum photosynthesis rate was obtained in control and was decreased with reduction of light intensity. To sum up، the results suggest that since no significant difference was observed in flowering characteristics between various coverings with UV-stabilizer ability and control، thus، growing dwarf Lisianthus cv. Matador could be recommended in open spaces.

One of the fast responding methods of plants to fertilizer application is foliar application، which saves fertilizer consumption too. Foliar application of micronutrients is a useful method، especially when roots are unable to absorb necessary elements from soil. The amount of available iron (Fe) in calcareous soils، with high pH، is low for sensitive plants، such as sorghum، to Fe deficiency. To compare the effect of foliar application of different Fe sources on growth traits، concentration and uptake of nutrients in sorghum، a greenhouse experiment was conducted as a completely randomized design with three replications. Treatments consisted of three levels of Fe (0، 90 and 180 mg Fe/L) from three sources of Fe (Fe nano-chelate، Fe-EDDHA and FeSO4. 7H2O). Results showed that application of all three sources of Fe increased shoot and root dry matter yield، plant height، leaf chlorophyll content، shoot Fe concentration and uptake as compared to control treatment. Foliar application of Fe reduced concentrations of P and Mn in shoot، but had no significant effect on root P، Mn and Fe concentrations. Concentration of Zn and Cu in shoot and root of sorghum was not affected by level of Fe application. Based on the results of this experiment، foliar application of FeSO4. 7H2O compared to Fe-EDDHA and Fe nano-chelate can increase growth and improve some characteristics of sorghum plants under greenhouse conditions. This result is economically affordable as well.

The purpose of this research was to assess and priority the training needs of greenhouse owners in Najaf-Abad county، Isfahan province، Iran. This research was an applied research and in terms of data collection was a survey research. The study population included all greenhouse owners (N=143) in Najaf-Abad county. The sample population was selected by using Kerjci and Morgan table (n=70). The main instrument used in this study for data collection was questionnaire. Validity of the questionnaire was confirmed by experts’ viewpoints. Reliability of the questionnaire was confirmed by examining Alfa Cronbach coefficient، which was obtained as more than 0. 7 in most of the categories. Results of the research showed that most greenhouse owners (47. 1%) had bachelor degree and work experience of less than 5 years (78. 6%). The area of most greenhouses (87. 1%) was less than 5000 m2. The results revealed that although educational needs at different stages of greenhouse management are different، but the most important of these needs can be summarized as: taking advantage of new technological developments، introducing high-yield seed varieties suitable for growing in the greenhouse، methods of pest control in greenhouses and reduction of agricultural products’ wastes.

Organic matters are important soil components which have considerable effects on phytoavailability of nutrients and improvement of soil physical، chemical and biological properties. The increasing demand for medicinal plants necessitates extensive research on them for sustainable agricultural development. In order to assess the effects of different levels of humic acid، compost and phosphorus (P) on growth traits and some micronutrients’ uptake by basil medicinal plant (Ocimum basiilicum L.) a factorial experiment was conducted in 2011 using a completely randomized design with three replications. Treatments consisted of three levels of humic acid (0، 10 and 20 mg/kg of soil; H1، H2 and H3، respectively)، three levels of urban waste compost (0، 5 and 10 ton/ha; C1، C2 and C3، respectively) and three levels of P (0، 10 and 20 mg/kg of soil، as triple super phosphate، P1، P2 and P3، respectively). After harvesting the plants، parameters such as dry weight of aerial parts، number of lateral branches، plant height and concentration and uptake of Fe، Mn، Cu and Zn in aerial parts were measured. Results showed that the effects of humic acid (at H2 and H3 levels) and compost (at C2 and C3 levels) were significant on height، number of lateral branches and shoot dry weight، as compared to control; but these two levels did not have significant difference. Interaction of humic acid and compost، along with P، on plant height، number of lateral branches and dry weight of shoots was not significant. Application of humic acid and compost increased significantly the concentration of Fe، Mn، Zn and Cu in plant shoots، and availability of Fe، Mn، Zn and Cu in soil was increased with the application of organic fertilizers. Interaction of humic acid and compost on concentration of Fe، Mn، Zn and Cu in plant and soil was significant. In interaction of humic acid and compost with P، the application of P reduced concentration of Fe، Mn، Zn and Cu in plant and their availability in soil. But، study of these interactions showed that application of organic fertilizers can somehow improve the negative effects of P on availability of these elements، and therefore، application of these fertilizers is recommended for improving soil chemical conditions and enhancement of growth traits of basil plant.