نشریه روابط خاک و گیاه
پیاپی 23 (پاییز 1394)

Sweet majoram (Majorana hortensis L.) is one of the native Iranian medicinal plants، which due to its aromatic secondary metabolites is used in traditional medicine. In production of medicinal plants، application of organic inputs has especial role in sustainable agriculture. Organic inputs، such as manures and compost، other than providing the necessary elements for plant growth، could improve the physiochemical structure of soil. This research was conducted to evaluate the growth traits، quantitative and qualitative yield، and constituents of essential oil of sweet majoram under the application of compost extract and inoculation of biofertilizers. The experiment was performed as split plot in time with three replications at Research Greenhouse of Ferdowsi University، Mashhad، Iran، in 2012. Main plots were 16 fertilizer combinations (Azotobacter (Azotobacter paspali)، (B1)، Azospirillum (Azospirillum brasilense) (B2)، mycorrhiza (Glomus intraradaices) (B3)، 10% compost extract (C1)، 20% compost extract (C2)، 30% compost extract (C3)، B1C1، B1C2، B1C3، B2C1، B2C2، B2C3، B3C1، B3C2، B3C3 and control) and sub- plots were three cutting stages during the growing season. Results showed that height of main stem، dry and fresh weight of sweet majoram was significantly affected by single and combined application of biofertilizer inoculation and compost extract at the first cutting and were higher than the second and third cuttings. Also، the most significant increase in height of main stem، fresh and dry weight and essential oil content of sweet majoram (43. 3 cm، 46. 07 g/m2، 27. 11 g/m2 and 0. 89%، respectively) was observed in C1B3 treatmeent. Constituents of essential oil were significantly affected by single and combined applications of biofertilizer inoculation and compost extract. Among the constituents، terpinen-4-ol (18. 01%) and cis-sabinene hydrate (15. 4%) allocated the highest and ledene (15. 4%) and camphene (0. 01%) the lowest amount.

Gerbera is one of the most important cut flowers in the world which is produced extensively in many commercial greenhouses. Nowadays, increasing yield and quality are production necessities. The aim of this research was evaluation of foliar application effects of salicylic acid and thiamine on quantitative and qualitative characteristics of gerbera flower. The experiment was conducted in a completely randomized design with four replications, in pots in greenhouse. Treatments included tap water (control), salicylic acid concentration (75 and 150 µM) and thiamine concentration (250 and 500 µM). Foliar application was performed in two stages, with an interval of two weeks. Results showed that the treatments had significant effect on quantitative and qualitative characteristics of gerbera flower. The largest flower diameter, the shortest growing period and the highest number of flowers was related to 75 µM salicylic acid treatment. The largest diameter of the stem was observed in 150 µM salicylic acid treatment. In this experiment, 500 µM thiamine treatment produced the greatest height of flowering stem and had the highest chlorophyll index. Therefore, it seems that salicylic acid and thiamine could increase production efficiency and improve gerbera flower quality, and in this respect, the best treatment was 75 µM salicylic acid.

In order to determine and evaluate the mechanization indices, including energy and economic, in production of greenhouse cucumber and tomato, a study was carried out using sequential design- factorial with three replications in Khuzestan province, Iran, during 2011-2012. The greenhouse structures and production methods in all the systems were similar. The evaluated treatments included two cultivated areas in the northern and southern parts of the province (first factor), cucumber and tomato plants (second factor) and area under cultivation of 1000, 3000 and 5000 m2 (third factor). First, by preparing a questionnaire and conducting the interviews with greenhouse owners, the questionnaires were completed for all the studied greenhouses and consumer information needed to calculate the energy inputs and energy and economic indices were then obtained. Results of the energy section showed that cucumber production in 3000 m2 areas in south of the province and tomato production in 5000 m2 areas in northern regions of the province had the highest energy productivity. In addition, results of the economic evaluation indicated that cultivation of tomato had more income and final gross profit, and with respect to internal rate of return index, the greenhouse tomato grown in northern regions of Khuzestan province was more affordable. Therefore, cultivation of greenhouse tomato in 5000 m2 areas in north of the Khuzestan province was suggested.

Lily (Lilium longiflorum L.) is one of the most important potted flowers, which is used largely as cut flower. An experiment, arranged as a factorial besed on completely randomized dasign with three replications, was carried out to evaluate the effects of pre-harvest foliar application of humic acid, salicylic acid and calcium chloride on quality and longevity of lilium cut flowers. Treatments included humic acid as factor a (0, 100, 500 and 1000 mg/L) and three salicylic acid concentrations (0, 150 and 200 mg/L) and two calcium chloride concentrations (300 and 600 mg/L) as factor b, which were sprayed at two stages before harvesting the flowers. Results showed that treating the plants with 500 mg/L humic acid increased water uptake and chlorophyll a content and decreased number of fallen florets. Application of 1000 mg/L humic acid increased total chlorophyll content. Pre-harvest treatment of flowers with 600 mg/L calcium chloride increased florets’ diameter, relative water content, chlorophyll b content and shelf life, as compared to other concentrations and different salicylic concentrations. In this research, the highest shelf life was observed for flowers sprayed with 1000 mg/L humic acid and 300 mg/L calcium chloride. Therefore, pre-harvest foliar application of humic acid, salicylic acid and calcium chloride could have positive effects on quantitative and qualitative traits of lilium cut flowers.

To investigate the effects of phosphorus (P) and pistachio waste (raw and dry) on growth and chemical composition of pistachio (Pistacia vera L. cv. Badami Zarand) seedlings, a factorial experiment in a completely randomized design with four replications was conducted. Treatments were three levels of P (0, 50 and 100 mg P/kg soil) and three levels of pistachio green hull (0, 3 and 6% w/w). The results showed that at the first level of P application, the 3% pistachio waste treatment increased root and shoot dry weight, number of leaves and leaf area of pistachio seedlings. While, application of 6% pistachio hull significantly decreased these parameters, as compared to the control. However, root and shoot nutrient concentrations including P, sodium, zinc, iron and copper at the first level of P were reduced by pistachio waste application. At the first level of pistachio waste, P application increased root and shoot dry weight, number of leaves and leaf area of pistachio seedlings. But, all nutrient concentrations of root and shoots, except P, were reduced by increasing P level. The best response of dry weight of roots and shoots, number of leaves and leaf area of pistachio seedlings was observed from application of 3% pistachio hulls and 50 mg P/kg of soil. In general, the results of this experiment indicated that application of 50 mg P/kg soil was more effective than 100 mg P/kg soil on growth and chemical composition of pistachio seedlings. Application of 3% pistachio green hull and 50 mg P/kg soil improved growth of pistachio seedlings.

Sophora japonica is a deciduous tree with fragrant white flowers and panicle inflorescence. This tree has not been used widely in the landscape of central. One of the reasons is lack of enough information about asexual propagation of this plant. In the present experiment, effects of different concentrations of indole butyric acid (IBA) and indole butyric acid-potassium salt (K-IBA) (0, 5000, 10000, 15000 and 20000 mg/L) was evaluated on hardwood cuttings of Sophora japonica with/without bottom heat. Results showed that no root formation occurred in the hardwood cuttings without bottom heat, while callus was produced. Bottom heat significantly affected all measured traits. The highest rooting percentage was obtained by 20000 mg/L IBA and K-IBA (56.66% and 53.33%, respectively), 80 days after planting the cuttings. The highest root length at 80th day after planting was obtained with 20000 mg/L K-IBA. Rooting percentage, number of roots, leaf area, roots carbohydrate content of roots and fresh and dry weights of roots, stem and leaves increased with increasing the hormones level. However, with decreasing hormones concentration, the ratio of sprout buds to dormant buds and the amount of carbohydrates in leaves were increased.

Effects of nutrient solutions on quantitative and qualitative indices of tulip (Tulipa gesneriana cv. Apricot parrot) were studied in a completely randomized design with 5 nutrient solutions, 4 experimental units and 3 replications. Plants were fed with five nutrient solutions (S1, S2, S3, S4 and S5) having NH4+-N/total N ratios of 0, 0.038, 0.074, 0.11 and 0.14, respectively. All nutrient solutions had similar concentrations of mineral elements. The five treatments consisted of 2.5 meq/L total N, and concentration of all the nutrients was 8.4 meq/L. Based on the results, increasing the ammonium level in nutrient solutions decreased N and total protein storage in the bulbs, but increased N concentration in the shoots. The ammonium level had no significant effect on potassium concentration of shoots, but increased phosphorus concentration in the shoots. Maximum calcium and magnesium concentration in shoots, wet weight and length and diameter of flowering stem were obtained in plants fed with S2 solution. Increasing the ammonium level increased number of bulblets, but decreased their size. Increasing the ammonium level decreased time to flowering of bulbs. The highest longevity of cut flowers was observed in plants fed with S2 solution. In general, based on the results of this research, with increasing the ammonium level in the nutrients solution, the qualitative traits of tulip, such as length and diameter of flowering stem, were increased, but longevity of cut flowers and number of produced bulblets were decreased.

Presence of heavy metals (such as lead, Pb) in plants is one of the major environmental stresses that decrease plant growth. Therefore, it is essential to determine the threshold of the plant's tolerance to these elements. In this regard, to evaluate the effect of different concentrations of Pb on eco-physiological traits of petunia plant, an experiment was carried out in the hydroponics greenhouse of Tabriz University, Tabriz, Iran, as a completely randomized design with 8 treatments and 4 replications. Treatments consisted of different concentrations of Pb (0, 0. 25, 0. 5, 0. 75, 1, 1. 5, 2 and 4 mg/L as Pb(NO3) 2). After applying the treatments, at the end of the growing season, the eco-physiological indices including photosynthesis, transpiration, stomatal conductance, stomatal resistance and leaf temperature were measured. Results showed that concentrations higher than 0. 75 mg/L Pb (NO3) 2 reduced the rate of photosynthesis, transpiration and stomatal conductance as compared to control. The highest stomatal resistance (8. 754 M/m2. s) was observed in 4 mg/L treatment; though it didnt have significant difference with 1. 0, 1. 5 and 2 mg/L treatments. The lowest stomatal resistance (7. 285 M/m2. s) was seen in 0. 25 mg/L treatment, which had no significant difference with control. The highest leaf temperature (33. 26 ْC) was observed in 2 mg/L treatment; though it didnt have significant difference with 1. 5 and 4 mg/L treatments. The lowest leaf temperature (26. 19 ْC) was obtained in the control treatment. After 0. 75 mg/L, the increase in leaf temperature was sensible. Based on the results, it appears that in soils having Pb concentration of ≤ 0. 75 mg/L, petunia plants are recommendable for cultivation in landscapes, accumulation of Pb, and phytoremediation.

Mint is an important medicinal herb that is cultivated in different parts of the world. In order to investigate the effects of salinity stress on morphological characteristics of spearmint (Mentha spicata L.), an experiment was conducted in 2013, based on complete randomized design, under hydroponic conditions, at Research Greenhouse of Faculty of Agriculture, Ferdowsi University of Mashhad, Iran. Treatments were five salinity levels (0, 30, 60, 90 and 120 mM of sodium chloride) with four replications. Growth medium was 2:1 cocopeat to perlite, and complete nutrients solution was used. Supplying plants’ nutrients was twice a week along the irrigation water application. When plants’ height was 30 cm, salinity treatments were applied and were continued till full flowering. At the end of the experiment, morphologic traits including plant height, number of main stems, number of lateral branches, leaf area, specific leaf weight, stem diameter, number of nodes, fourth internode length, and spike length were measured. Results showed that salinity stress had significant effects on leaf area, fresh and dry weights of leaf, stem and root, plant height, number of lateral branches, number of nodes, fourth internode length, and spike length. The highest leaf area, leaf dry weight, plant height and number of lateral branches were observed in control treatment. The lowest leaf area and leaf dry weight were obtained in salinity level of 120 mM, and the lowest plant height and number of lateral branches were observed in salinity levels of 90 mM and 120 mM. Salinity had no significant effect on fresh weight of shoot to root ratio, fresh weight of leaf to root ratio, specific weight of leaves, number of main stems and stem diameter. According to the results, it appears that spearmint is sensitive to salinity stress and it cant tolerate salinity levels higher than 30 mM sodium chloride.

In order to study the effect of bacterial growth on water use efficiency of alfalfa, a greenhouse experiment, as factorial based on completely randomized blocks design with three replications, was conducted at Faculty of Agriculture, University of Mohaghegh Ardabili, Ardabil, Iran, in 2012. Treatments consisted of 3 levels of water stress (75, 55 and 35% of field capacity) and seed inoculation at 4 levels (no inoculation (control), inoculation with mycorhhiza G. mosseae, inoculation with rhyzobium S. meliloti, and inoculation with combination of mycorhhiza and rhyzobium). Results showed that water stress and seed inoculation have significant effect (P≤0.01) on leaf nutrients content. Water stress reduced absorption of phosphorus (23%), potassium (8%), iron (4%) and increased sodium absorption (14%) in non-inoculated seeds. Inoculation of seeds reduced stress effects and combined inoculation had the highest effect. Stomatal conductance and water use efficiency were affected (P≤0.01) by inoculation and water stress. Stomatal conductance was decreased during the stress period and seed inoculation with mycorhhiza G. mosseae was most effective on increasing stomatal conductance (47% at the highest level of stress). Water use efficiency increased as a result of water stress and inoculation. The highest value of water use efficiency (0.166 mg/kg) was obtained in the combined inoculation with 35% field capacity treatment. Results of regression equations showed that during the inoculation, contribution of phosphorus and potassium in regulation of stomatal conductance was increased and contribution of sodium was decreased. However, during the stress period, the share of potassium and sodium was increased in stomatal conductance and the share of phosphorus was reduced. Also, stress increased the role of stomatal conductance in water use efficiency. However, inoculation reduced the role of stomatal conductance in water use efficiency.

Recently, attentions have been taken on the investigations regarding the use of nano-sized compounds in different fields including agricultural sector. Due to the importance of evaluating the fate and operation of nano-particles in plant systems, in this survey, responses of 13 wheat genotypes to the effect of nano-iron chelate fertilizer in the Hoagland solution under the conditions of ordinary iron chelate and nano-iron chelate, with concentration of 22.5 mg/L, was studied. This experiment was carried out in Research Greenhouse of Soilless Culture Research Center, Isfahan University of Technology, Iran, in the spring of 2013. Results showed that there were considerable positive and negative variations among wheat genotypes in response to application of nano-sized iron chelate fertilizer. Under the application of iron chelate, among the different measured traits, number of tillers and root/shoot ratio had the highest coefficient of variations, and the lowest values were observed for chlorophyll flourescence and green leaf surface. Under the application of nano-iron chelate, number of tillers and root/shoot ratio had the highest coefficient of variations, and the lowest value was observed for chlorophyll flourescence content. Nano-iron chelate fertilizer caused reduction of average dry matter yield of shoots, leaf area and root volume by 14.1, 9.5 and 8.9 percent, respectively, and increased root/shoot ratio by 13.7% for some wheat varieties, in comparison with the ordinary iron chelate. In response to nano-iron chelate fertilizer, compared to ordinary iron chelate, Line-9-shoory produced the highest total dry matter (14.49% increase) and Star variety had the lowest total dry matter (-51.82%).

The required water for greenhouses in Kishestan, Soume-e-Sara town, Guilan province, Iran, is mainly provided by underground resources that have inappropriate quality. One way to reduce the impact of salinity an plant growth is proper nutrition. This greenhouse research was conducted to evaluate the effect of water salinity and foliar spray of calcium (Ca) and silicon (Si) on growth and vase life of gerbera in a factorial experiment based on compeletly randomized design with two factors. The first factor was salinity of irrigation water at two levels (0 and 1.5 dS/m) and the second factor was foliar spray at seven levels (without spray, twice Ca spray, four times Ca spray, two times Ca spray + once Si spray, twice Ca spray + twice Si spray, four times Ca spray + once Si spray, and four times Ca spray + twice Si spray), each with three replications. Results showed that four times Ca foliar spray led to an increase in stem hight, stem and neck diameter, postharvest life and Ca concentration of shoots. In all spray treatments, number of flowers in zero salinity was more than 1.5 dS/m treatments. In general, in case of using low-quality water (electrical conductivity of 1.5 dS/m), the effects of salinity on dry and fresh weights of gerbera plant and vase life of its flowers can be reduced by foliar application of Ca and Si. Since inappropriate water quality in Rasht Greenhouse Complex, Soume-e-Sara town, is one of the main problems of the farmers, especially in growing the ornamental plants, effects of salinity on plant growth could be alleviated with foliar spray of nutrients, especially Ca and Si. In this respect, four times spray of Ca and also twice spray of Ca + twice spray of Si are recommended.

Salinity is a very serious problem for agricultural development, especially in arid and semi-arid regions. On the other hand, many benefits of soilless culture have caused the expansion of these systems in these areas. In this research, in order to investigate the effects of different substrates and salinity stress on physiological characteristics and yield of broccoli, an experiment was conducted as factorial, in which the main factor was substrate (cocopeat, perlite, sand, 25% cocopeat+75% perlite, 25% perlite+75% cocopeat and 50% peat+50% pumice) and the sub factor was salinity stress (0, 100 and 150 mM NaCl) with 4 replications. Results indicated that substrate, different levels of salinity and their interaction had significant effects on morphological characteristics, days to flowering, fresh and dry weight of leaves, nutrients concentration and weight of the broccoli head. Maximum values of the aforementioned factors were observed in the zero salinity level and 50% peat+50% pumice substrate. This means that substrate can be effective on the effect of salinity on plants. High levels of salinity caused a reduction in growth and yield of broccoli and this growth reduction was accompanied by the reduction of chlorophyll and content of Ca, K, and Fe and increased Na and Cl concentration in leaf tissue. The best growing medium, either in saline or non-saline conditions, was 50% peat+50% pumice. Although broccoli growth was not suitable in perlite medium, this substrate caused its early maturing. In this experiment, salinity treatment reduced the head weight of broccoli, in addition to decreasing the quality of yield. According to the results, 50% peat+50 pumice is recommended as a proper substrate for production of broccoli.

Identification of medicinal plants with tolerance to salinity stress has an economical importance in Iran. This study was carried out to evaluate the effects of salinity stress on different Morpho-Physiological traits of Foeniculum vulgare Mill in germination and seedling stage in hydroponic condition. The experiment was conducted as a split plot based on a Randomized Complete Block Design (RCBD) with four (in first experiment) and three (in second experiment) replications. Salinity effects of NaCl [0, 50, 100, 150 200 (Mm)] was evaluated on three genotypes of Foeniculum vulgare (Estahban, Isfahan, Shiraz). Analysis of variance showed that salinity levels reduced the percentage of germination, seed vigor index, rootlenght, stem length, root dry weight, shoot dry weight, biomass, the ratio of shoot to root, chlorophyll index, chlorophyll a and b and caroteniod content. Significant variation was observed between different genotypes on different levels of salinity. Tolerance to salinity in seedling was more than germination. In two experiments, the genotype of Shiraz showed superiority in view point of tolerance.

Drought has adverse effects on plant growth and production. Plants respond to drought stress through biochemical and physiological processes. In the present study, physiological responses of two cumin (Cuminum cyminum L.) ecotypes including Ravar and Gonbad, which belong to dry and sub-humid regions of Iran, respectively, were evaluated in a split-plot factorial experiment with three replications in controlled greenhouse conditions. Physiological traits such as relative water content, relative leaf water loss and electrolyte leakage were measured. Analysis of variance showed that there are considerable genetic variations for drought tolerance between the ecotypes. Drought stress decreased relative water content and relative leaf water loss rate, while electrolyte leakage was significantly increased in both ecotypes. Most of the significant changes were recorded in Gonbad ecotype. The Ravar ecotype demonstrated higher tolerance to drought stress, as compared to Gonbad ecotype, which can be due to compatibility of this genotype to water-deficit conditions. Therefore, this ecotype was recommended as a tolerant ecotype to drought stress. In conclusion, the investigated traits in this experiment were found to be valuable criteria in selection of drought-tolerant ecotypes at seedling stage under greenhouse conditions.