جستجوی مقالات مرتبط با کلیدواژه "leaf dry weight" در نشریات گروه "زراعت"

This study attempts to investigate the effect of application of humic acid and seaweed extract on morphology, growth, yield, and yield components of quinoa under drought stress in 2018-2019 in two different locations, Qasr Shirin and Dalahou. It has been performed as split plots in a randomized complete block design with 4 replications. Experimental treatments include three irrigation treatments (full irrigation, irrigation cut-off at the beginning of flowering and irrigation cut-off at the beginning of seed filling) and foliar spraying treatments with different amounts of humic acid (foliar application at the rate of 1.5 kg / ha and 2 Kg / ha) and seaweed extract (foliar application at 1 kg / ha and 1.5 kg / ha) along with a control treatment. Results show that seed yield in Dalahou region under normal condation has been 24.78% higher than Qasrshirin region. Seed yield in different irrigation treatments under the influence of foliar application show that in all irrigation treatments, the effect of foliar application of humic acid and seaweed extract on seed yield has been positive compared to the control. In full irrigation conditions, the highest seed yield is obtained from foliar application of humic acid, while in irrigation cut-off treatments, the effect of seaweed extract on seed yield has been better than humic acid. The weight of 1000 seeds in quinoa produced in Dalahu region has been more than Qasrshirin region but in both regions drought stress has reduced the 1000 seeds weight. In all irrigation treatments, application of humic acid and algae extract has increased 1000-seed weight.

Auxin produced by plant growth-promoting bacteria (PGPR) in the wheat rhizosphere, can improve plant yield under water deficit stress condition. To investigate this issue, a completely randomized factorial design with three replications was conducted under greenhouse condition at the University of Maragheh, Eastern-Azarbayjan, Iran during 2019. Treatments were two types of growth-promoting bacteria (Bacillus simplex 40, Bacillus simplex 52); two moisture levels (50% and 80% of water holding capacity in perlite) and two levels of tryptophan (0 mg L-1 and 100 mg L-1). Under the condition of 50% of water holding capacity, the application of tryptophan without bacterial inoculation decreased wheat dry matter yield by 5%. Inoculation of Bacillus simplex 40 in the absence of tryptophan led to 25% increase in wheat dry matter yield while application of tryptophan reduced the trait by 17%. Under the stress condition, catalase enzyme activity increased by 33% and guaiacol peroxidase activity increased by 2.3% in inoculation treatments compared to control treatments. In conclusion, bacterial inoculation was able to increase wheat dry matter yield by improving the wheat antioxidant system under drought-induced oxidative stress. Furthermore, the decrease in wheat dry matter in the presence of tryptophan treatment may be attributed to probable hormonal disorders in wheat caused by high concentration of applied tryptophan.

Salinity is one of the environmental abiotic stresses and most important factors limiting the growth and production of plants around the world, which dramatically affect various aspects of plant growth and development through anatomical, morphological and physiological changes (Siringam et al., 2011). Saline environments decrease the growth and yield characteristics of plants and increase some physiological properties such as proline content and electrolyte leakage (Noreen et al, 2010). On the other hand, in the recent years, the role of symbiotic fungi and polyamines in plants tolerance to environmental stress such as saline conditions are pronounced. Morever, due to the importance of medicinal plants, many researches of plant sciences have focused on the various aspects of the application of these plants (Vafadar et al., 2018). Therefore, the present study was conducted to investigate the growth and physiological response of stevia (Stevia rebaudiana Bertoni) medicinal plant to inoculation with endophytic fungi and foliar application of spermidine polyamine under salt stress conditions.

This experiment was conducted at research greenhouse of Genetics and Agricultural Biotechnology Institute of Tabarestan (GABIT) at Sari Agricultural Sciences and Natural Resources University using factorial arrangement based completely randomized design with three replicates in spring and summer of 2016. The treatment consisted of salinity in three levels (0, 6 and 12 dS/m), fungal symbiosis treatments including four levels [non-inoculated (control), inoculation with Piriformospora indica (Pi), inoculated with Trichoderma virens (Trich) and co-inoculation of two fungi (Pi+Trich)] and foliar application of spermidine in three levels (0, 0.75 and 1.5 mM). Seedlings of stevia after inoculation with fungi transfered to adaptation chamber for 40 days and then moved to the greenhouse. Plants were irrigated with tap water until the end of vegetative stage and then irrigated with saline water treatments containing mixture of distilled and Caspian sea water. The Spermidine was foliar applied one week before salinity stress. Two weeks after salinity stress, leaf samples were prepared to measure leaf relative water content (RWC), electrolyte leakage (EL), proline content and soluble sugars. Finally, the plants were removed from the pots and the growth and yield traits were measured.

The result showed that in saline conditions, endophytic symbiosis, especially Pi+Trich, increased the stem dry weight (40-64%) and leaf dry weight (44-50%), relative water content (5-30%) and proline content (40-64%), and reduced EL (11-20%). Also spraying 0.75 mM spermidine signiticantly increased both leaf dry weight and plant height. Fungal symbiosis, especially Pi+Trich, and spermidine 0.75 mM resulted in an increase in the RWC. Also, spraying with polyamine spermidine at both concentrations of 0.75 and 1.5 mM increased soluble sugars and inoculated with endophytic fungi, particularly co-inoculation of two fungi, led to a reduction in the content of sugar (17%) in the stevia leaf. At the most levels of salinity and fungal treatments, spermidine, especially at the rate of 0.75 mM, led to increase in stem diameter (10-35%) and leaf area (35-46%).

In general, the results of the present study indicated a negative effect of salinity on the growth and physiological characteristics of the stevia plants. However, inoculation of endophytic fungi, particularly co-inoculation of Pi and Trich, improved the growth and physiological parameters and ameliorated adverse effects of salinity in stevia plants. Morever, the spermidine (especially 0.75 mM) induced salt stress tolerance in stevia plants and showed a synergetic effects with endophytic fungi in terms of the mentioned parameters.

In this study, the effect of spraying of Zinc oxide nanoparticles at three concentrations (0, 1000 and 2000 ppm) on the response of Capsicum annuum L. to different levels of salinity (0, 25, 50 and 75 mM NaCl) was evaluated. The experiment was carried out as factorial based on randomized complete block design with four replications in pot culture conditions. The high concentration of salt and Zinc oxide nanoparticles reduced the amount of chlorophyll, carotenoids, total phenol, leaf dry weight, proline content, total soluble carbohydrate, plant height, stem diameter and catalase enzyme activity but increased the amount of malondealdehyde (MDA). Rising the salinity level to 50 mM, increased the soluble carbohydrates content but further increase to 75 mM salinity led to decrease in the soluble carbohydrates content. The interaction of salinity and Zinc oxide nanoparticles was significant on chlorophyll, proline, malondealdehyde (MDA), total phenol, carotenoids, and soluble carbohydrates concentrations, and leaf dry weight. The result of this experiment showed that Zinc oxide foliar application in the form of nanoparticles is potent to reduce the damages of salinity to pepper.

Since the leaves are the main source of production of photosynthetic substances in plants, dry matter production and crop yield potential is largely depend on the leaf surface, and many environmental changes affect growth and yield through changes in leaf area. Hence, green leaf area per plant and leaf area index measure in almost all studies of crop physiology to understand the mechanism of yield alteration. However, measurement of leaf area compared with other traits such as plant height and total plant dry weight is very difficult, precise instruments and spend more time and cost. Therefore, according to the allometric relationships in plants, extensive studies were done to find the relationship between leaf area and other plant traits that their measurement is easier, faster and cheaper, and does not require expensive equipment. Allometric relationships in plants reveal changes in the growth of an organ of plant than to all or another part or organ of plant. The leaf area in plant as main source of photosynthetic substances closely associated with the growth and yield. Thus, it is usually measured for justifying variations of the growth and yield. Due to the difficulty, time consuming and requires devices to measure leaf area, an alternative approach for measuring the leaf area is the use of allometric relationships between leaf area and traits that their measuring is easy and quick and requires no expensive equipment. This study aimed to obtain the allometric relationships between green leaf area and a number of vegetative attributes such as number of leaves per main stem, green leaf dry weight, total dry weight of vegetative parts of plant. Allometric equations was used successfully to calculate leaf area in various crops such as cotton, wheat, chickpea, faba bean, peanuts, soybean and sweet sorghum. The effects of three factors cultivar, inter and intra row spacing on the allometric relationships were examined. This experiment was conducted using two cultivars of faba bean (a conventional, Barecat and a new cultivar, French), three inter row spacing (25, 50 and 75 cm) and two intra row spacing (8 and 15 inches) in a randomized complete block design with 4 replications in the farm of Gorgan University of Agricultural Sciences and Natural Resources during 2010 2011 growing season. Sampling to measure the green leaf area and leaf dry weight and other vegetative traits during the growing season was carried out with intervals of 7 to 15 days (depending on the temperature and rate of plant growth). Different mathematical functions were fitted to the data to obtain allometric relationships. To compare the accuracy of the equations, coefficient of determination (R2) and root mean square error (RMSE) were used. Higher coefficient of determination, and lower coefficient of variation and root mean square error reflects the higher accuracy of the equation to describe allometric relationships. According to the results of this experiment, the relationship between leaf area and leaf dry weight and total plant dry weight in faba bean was not affected by cultivar, inter and intra row spacing, statistically. Thus, an equation was fitted to leaf area data against leaf dry weight or total plant dry weight in all treatment (both cultivars and all inter and intra row spacing). Also, results of this study showed that the relationship between green leaf area and leaf dry weight as well as number of nodes per main stem has higher coefficient of determination (0.98 for green leaf dry weight, and 0.98 and 0.95 for node number per main stem in 8 and 15 cm intra row spacing, respectively) and lower the root mean square (1.05 for green leaf dry weight, and 1.08 and 1.064 for node number per main stem in 8 and 15 cm intra row spacing, respectively) than other traits. Since the relationship between green leaf area and green leaf dry weight per plant had a higher coefficient of determination (0.98) as well as smaller root mean square (1.05) than other traits including leaf number per main stem, as well as the ease of measuring the green leaf dry weight, it is suggested that the relationship between leaf area and leaf dry weight (a segmented relationship) is used to estimate green leaf area during the growing season in faba bean. Also, this relationship can be used to predict faba bean leaf area with sufficient accuracy in the simulation models.

  Stevia rebaudiana Bertoni in an ancient perennial shrub of South America, produces diterpene glycosides that are low-calorie sweetener sand about 300 times sweeter than saccharose (Savita et al., 2004). Stevia extracts, besides having therapeutic properties, contain a high level of sweetening compounds, known as steviole glycosides, which are thought to possess antioxidant, antimicrobial and antifungal activity. Stevia cultivation and production, especially in Iran, would further help those who have to restrict carbohydrate intake in their diet; to enjoy the sweet taste with minimal calories. In Iran, the best area that has the most similarity of favorable climate condition for Stevia cultivation is the north of Iran. However, poor soil aeration associated with excessive moisture usually influences plant establishment and growth negatively in this part of Iran. Heavy textured soils in northern regions of Iran are more susceptible to waterlogging after heavy rain, and hypoxia is likely to limit Stevia growth. Thus waterlogging is considered as one of the important limiting factors for Stevia cultivation in such regions. On the other hand, Oxidation-reduction systems in the soil, which are generally stable as long as the soil is bathed in oxygen, become unstable when the oxygen supply is restricted. Nitrate is stable in well-aerated soils but become unstable when the oxygen supply of the soil is cut off. Nitrogen is subjected to loss through denitrification because of the ability of facultative anaerobes to substitute nitrate for oxygen. Advantage can be taken from the reducing conditions in waterlogged soils to increase the utilization of nitrogen fertilizer. The objectives of the present experiment were to investigate the effects of waterlogging stress and the alleviation of the waterlogged damage by the application of nitrogen fertilizer in Stevia. Material and A greenhouse pot experiment was conducted in University of Guilan, in 2013. The experimental design was factorial using completely randomized design layout with three replications. Treatments included four waterlogging levels; (0, -5, -10 cm from soil surface and normal irrigation as control), in periods of 2 and 4 days of waterlogging and two levels of nitrogen (6‰ and no nitrogen spraying as control) by foliar spraying from source of urea. Because the economic organ of Stevia is its leaves samples were taken before flowering stage. Results showed that measured shoot traits including leaf percentage, leaf area density, specific leaf weight, leaf dry weight, leaf area, plant height, number of lateral branch, number of leaves were significantly different among treatments. Nitrogen application improved plant height (14%) (Bakhshandeh et al., 2016) but deceased leaf area density (14%) compared with control. Interaction of waterlogging duration and nitrogen fertilizer significantly influenced leaf percentage, specific leaf weight and leaf dry weight. During water logging period increase from two to four days, nitrogen application improved leaf percentage by 4.5%, specific leaf weight by 11%, and leaf dry weight by 14%. In addition, interaction between water logging level and nitrogen application significantly influenced specific leaf weight, number of lateral branch and leaf dry weight. For specific leaf weight in -5 cm water logging level, nitrogen fertilizer application resulted in 12% increase compared with the same water logging level but without nitrogen fertilizer. Nitrogen application under -10 cm water logging level improved the number of lateral branches by 9% compared with complete water logging level without nitrogen application. Also for leaf dry weight, nitrogen application under -10 cm water logging effect resulted in 11% increase compared with no nitrogen application. Generally, the results of this experiment show that nitrogen application under water logging stress improved growth features of Stevia although water logging stress reduce growth characteristics of Stevia. Nitrogen application under the highest waterlogging level improved leaf dry weight by 10% compared with no nitrogen application treatment. Because economic part of Stevia is its leaves, it is likely that nitrogen application under water logging stress improve this trait (Rashid et al., 2013). Results of this experiment showed that although level and duration of flooding stress caused a reduction in stevia leaf production but nitrogen application can ameliorate the negative effects of the stress on this trait. Since leaf dry weight is the economical yield of stevia, N application will improve yield if this plant under flooding stress

Availability of nutrients needed by plants and ambient light are important in the growth and synthesis of active substance of medicinal plants. Various nutritional combinations have been assessed to study their effect on improving field management and production of medicinal plants. Nitrogen is often a limiting nutrient in plant growth in most agricultural soils. Nitrogen is a major component of chlorophyll, proteins, nucleic acid, vitamins and other organic compounds by which plants use sunlight energy to produce sugars from water and carbon dioxide (i.e., photosynthesis). It is also a major component of amino acids, the building units of proteins. Phosphorus is another element which has an important role in nearly every plant process that involves energy transfer. High-energy phosphate, contained in the chemical structures of adenosine diphosphate (ADP) and ATP, is the source of energy that drives the variety of chemical reactions within the plant. Nitrogen and phosphorus can be supplied through fertilizers or animal manure. Various studies show that combined use of manure and chemical fertilizers (as N, P and …) have positive effects on soil fertility and growth of plant as well as protecting the environment. Studies also show the effect of adequate nutrients on plant growth parameters, light absorption and biosynthesis in medicinal plants. Therefore, the present study was conducted to evaluate the effect of organic amendments enriched with chemical fertilizers (nitrogen and phosphorus) on effective traits in light absorption and alcoholic extract of hemp in two consecutive years in Birjand. To study the effect of different levels of animal manure and chemical fertilizers, a split factorial experiment, based on complete randomized blocks design with three replications was conducted at the research Farm of Faculty of agriculture, University of Birjand, during 2013- 2014 growing seasons. Experimental factors include application of animal manure (well-rotted farmyard manure) at a rate of 0, 10, 20 and 30 ton ha-1 to the main plot. The sub plots were received nitrogen at rate of 0, 50 or 100 kg ha-1 (nitrogen in form of Urea) and phosphorus at rate of 0 or 80 kg ha-1 (P2O5 as triple superphosphate). Measured traits were shoot height and diameter, leaf area and leaf number, nitrogen percentage of leaf, canopy light absorption, shoot and leaf dry weights, percentage of extract of leaves and seeds. Nitrogen content of plants was determined by Kjeldahl method and light Absorption was measured by Sun scan. The data were statistically analyzed by SAS software (V. 9.1). Comparison of the means was performed using FLSD test at the 0.05 level of significant. The results showed that canopy light absorption highly correlated with the leaf numbers (0.676**), shoot height (0.621**), nitrogen percentage of leaf (0.543**) and shoot diameter (0.481**) respectively. Application of 30 ton ha-1 of animal manure resulted in less efficiency in increasing shoot height and diameter, leaf area and number and nitrogen percentage of leaf. The absorption of light by plant was higher in treatments with higher nitrogen content in leaf. The study showed that weight of shoot and leaf following treatment increased by animal manure, nitrogen and phosphorus supplements, which subsequently increased final weight of extract from leaves and seeds.
Application of 30 ton ha-1 of animal manure and 100 kg ha-1 of nitrogen resulted in 20.1% and 20.2% increase in content of leaf extract respectively, while application of 100 kg ha-1 of nitrogen resulted in 20% increase in total weight of extracts from seeds. Seed extracts were also highly correlated with the dry weight of leaves. Therefore, the study suggests that adequate nutritional supplement to soil can increase plant growth and final weight of the leaf and seed extracts from plants. Most seed extract estimated in combined treatment of 30 ton ha-1 animal manure and 80 kg ha-1 of phosphorus. The rate of plant growth was lower in the first year compare to the second year, which can be due to higher salinity of soil and animal manure and temperature of germination in the first year.
Overall, the findings of this study showed that application of 30 ton ha-1 of animal manure can provide the plants with adequate level of nitrogen and phosphorus resulting in increased level of extracts of leaf and seed in hemp plant and can reduce the need for nitrogen and phosphorus fertilizers use

To estimate genetic parameters of agronomic traits in tobacco, six oriental-type tobacco varieties were crossed based on diallel mating system without reciprocals in 2013. F1 populations and six parental lines were planted using randomized complete block design with three replications in 2014 at research field of Urmia Tobacco Research Center, Urmia, Iran. Some charectristics including number of leaves, leaf length and width, plant height, stem diameter, internodes length, fresh leaf and dry weight were measured and analyzed using Griffing method II and mixed effect model B. Analysis of variance revealed significant differences (P≤0.01) between varieties for plant height, leaf number and fresh weight and for leaf dry weight (P≤0.05). General combining ability of varieties for all aforementioned traits was significant at the 1% probability level. Specific combining ability was also significant at the 1% probbaility level for plant height, leaf number and fresh weight. Both additive and non-additive (dominance) gene effects were involved in controlling of plant height, leaf number and fresh weight, however, additive gene effect controlled leaf dry weight. In general, the ratio of GCA to SCA was significant for all of the studied traits except leaf fresh weight which emphasizes the importance of additive effect in inheritance of this trait.

Saffron is one of the most important crops and medicinal plants in Iran and plays an important role in non-oil exports of the country. Saffron is cultivated in most part of Iran, because of low water requirement and well adaptation to diverse environmental condition. Therefore, the present study is to investigate the effects of corm weights and gibberellic acid on yield and vegetative characteristics of saffron. The effects of applications of gibberellic acid hormone (GA) and mother weight corm on flower yield and growth characteristics of saffron were evaluated under field conditions. Treatments were tow levels of gibberellic acid (0 and 20 ppm) and three mother corm weights (0.1- 4, 4.1- 8 and 8.1- 12 g). The experiment was designed as factorial arrangement based on randomized complete block design with three replications at the Research station of Faculty of Agriculture University of Birjand during growing season of 2016-2017. The measured indices were included of leaf characteristics (leaf length, fresh and dry weight, chlorophyll a, b and total leaf) and flower characteristics (flower number and fresh total yield, average stigma length, stigma fresh and dry yield). The results indicated that mother corm weight had significant effect on all flowering traits, so that the highest flowers number, flower yield (37.7% per m2,6.59 g. m-2), flowers fresh weight and stigma fresh weight (0.381 g, and 0.025) was observed from corm weight 8.1-12 g and the least of them was recorded from corm weight 0.1-4 g. Also, with increase corm weight, increased the leaf traits (leaf length, leaf weight, chlorophyll a, b and total leaf), so that the highest and lowest of these traits were recorded with corm weight 8.1-12 g and 0.1-4 g, respectively. It was found that gibberellic acid had significant effect on most vegetative traits of leaves, so that the highest leaf length (32.02 cm), leaf number (28.26), Leaf fresh weight (0.388 g), chlorophyll a (0.203 mg. g) were obtained from gibberellic acid treatment. but, gibberellic acid reduced the number of flowers. Also, interaction effects of gibberellic acid and corm weight had a significant effect on chlorophyll b and stigma length. According to this study, results showed that corm weight (12-8/1 g) had strong impact on growth characteristics and yield of saffron, increased saffron vegetative and reproductive characteristics, while, the use of gibberellic acid only improved the vegetative traits and didn't affect on saffron flowering traits

Maize (Zea mays) is a cereal crop that is grown widely throughout the world in a range of agroecological environments. .Its value as a cost-effective ruminant feed is one of the main reasons that farmers grow it. However, lack of nutrients such as N and P, are the principal obstacles - to crop production under low input agricultural systems leading to dependency on chemical fertilizers. Long-term use of chemical fertilizers destroy soil physicochemical properties and it reduced permeability which restricts root growth, nutrient uptake and plant production. Therefore, the use of organic fertilizers can help to enrich the soil root zone As a result growth and yield will improve.
In order to study the effects of different levels of vermicompost and foliar application of tea compost on growth characteristics of the hybrid maize genotype 713, a greenhouse experiment was conducted as a factorial experiment in randomized complete block design with three replications at the Vali-e-Asr University of Rafsanjan, during 2013. Treatments were included vermicompost (0, 5%, 10%, 15%, 20%, 25% and 30% pot weight) and tea composts (foliar application, non-foliar application). Measured traits were included root dry weight, root volume, leaf dry weight, stem dry weight, macro nutrient concentration (N and P) and micro nutrient concentration (Zn, Mn, Fe and Cu). All the data were subjected to the statistical analysis (two-way ANOVA) using SAS software (SAS 9.1.3). Differences between the treatments were performed by Duncan’s multiple range test (DMRT) at 1% confidence interval.
Results indicated that leaf and stem dry weight affected by the application of vermicompost and tea compost. However, the interaction effects had no significant effects on the leaf and stem dry weight. Application of tea compost increased 20% and 50% leaf dry weight and stem dry weight of corn compared to non- foliar application, respectively. The highest leaf dry weight and stem dry weight observed at 25% pot weight vermi compost, and lowest leaf and stem dry weight observed in control. Root volume and root dry weight affected by the interaction effects of vermi compost and tea composts. The highest root dry weight and root volume observed in 30% weight in non-foliar application condition. The highest root dry weight and root volume observed in 15% pot weight in tea compost application condition. It is also resulted that Fe concentration of shoot had affected by the application of tea compost, and using vermi compost affected the concentration of Zn, Fe and N in shoot. Application of tea compost increased 15% Fe concentration of shoot compared to non- foliar application. Using vermi compost of 30, 30 and 15% per pot weight increased concentration of Fe, N and Zn of corn shoot, respectively.
Result indicated that Mn, Cu and P concentration of corn shoot affected by interaction effects of vermicompost tea compost. It is also resulted that the highest concentration of Mn, and Cu observed in 15% pot weight in tea compost application condition and the highest concentration of P observed in 5% pot weight in tea compost application.
Nutrient contents of vermicompost and tea compost are comparable with other organic fertilizers. Totally, it seems that using tea compost foliar application due to bioavailability nutrient could decrease the amount of vermicompost application.

The salinity of water resources and soil is one of the most important agricultural problems in arid and semi arid regions of Iran. In order to investigate the effects of saline irrigation water on phyllochron and leaf appearance rate of barley cultivars, a factorial experiment based on randomized complete block design with three replications was conducted at the greenhouse of Faculty of Agriculture, University of Mohaghegh Ardabili during 2010. Studied factors were barley cultivars (Makoei, Lisive and Sahand) and salinity of irrigation water in pots in four levels (common water as control as well as irrigating with saline water levels of 20, 40 and 60 Mm using NaCl). Traits such as leaf appearance rate, phyllochron, the number of leaves per plant, leaf area index and leaf dry matter per plant were studied. The results showed that phyllochron (the time interval between the appearance of successive leaves on a shoot) were significantly affected by saline irrigation water, cultivar and interaction of saline irrigation water× cultivar. Increasing salinity increased the phyllochron, while decreased the rate of leaf appearance. There were significant differences amongst cultivars in this regard. Leaf appearance rate of Sahand cultivar was more than other cultivars. Means comparison of treatment compounds of saline irrigation water× cultivar showed that the greatest phyllochron was obtained in treatment compounds of irrigation with salinity 60 Mm × Lisive cultivar and the lowest of it was observed in irrigation with common water × Sahand cultivar. saline irrigation water decreased leaf area index. In all salinity levels, the trend of leaf area index variations was similar until 24 days after sowing. From 24-64 days after sowing, LAI showed a progressive trend, so that it reached to a maximum level at 64 days after sowing and then decreased slowly till 74 days after sowing. This might be related to increased aging of leaves, shedding and competition between plants for light and other resources. The highest leaf area index (1.95) was obtained in treatment compound of irrigation with common water×Sahand cultivar and the least of it (0.89) was observed in irrigation with salinity of 60 Mm×Lisive cultivar. Saline irrigation water reduced the number of leaves per plant and leaf dry weight. It seems that in order to increase the leaf appearance rate, LAI and number of leaves per plant, it can be suggested to employ the Sahand cultivar under irrigation with saline water.

Spearmint (Mentha spicata L.) is one of the most important mint family that has numerous applications in food, cosmetical, and pharmaceutical industries due to its valuable medicinal properties. The essential oil content and composition are affected by genotype, climatic, edafic condition and agricultural practices. In this research, the effect of harvest time on plant fresh and leaf dry weights, essential oil content, yield and composition as randomized complete block design with twelve treatments and three replications was studied. Result showed that harvest time had a significant effect on plant fresh and leaf dry weights, essential oil content and yield. The highest plant fresh (2507.3 gr.m-1) and leaf dry (452.2 gr.m-1) weights recorded in July had no significant difference with that of June. Plants also showed the highest amount of essential oil content (2.75%) and yield (6.99 gr.m-1) in September and July, respectively. The main essential oil components were carvone, limonene, careen, α-pinene, myrecene, β-borbonene, cisdihydrocarvone, dihydrocarveol, dihydrocarvyl acetate, Pulgone and trans caryophylene. The highest (57.46%) and lowest (16.83%) amounts of carvone were observed in October and February, respectively. The highest (32.62%) and lowest (2.19%) amounts of limonene were observed in September and March, respectively. The maximum amount of careen (2.87%) was obtained in November. Cis dihydrocarvone, dihidrocarveol and dihydrocarvyl acetate were increased during winter. Overall, in regard to essential oil yield and carvone content, the best time to harvest is from June to September.

In order to investigate the effects of plant growth promoting rhizobacteria inoculation on growth criteria and yield of spring barley in different levels of nitrogen and phosphorus fertilizers, an experimental was conducted in two years at the Research Farm of Islamic Azad University, Ardabil branch during two growing seasons of 2009-2010 and 2010-2011 years. Experiment was conducted as Factorial split-plot design with three replications. The combination of nitrogen fertilizer in three levels (0, 40 and 80 kg N ha-1 as urea) and phosphorus fertilizer (0, 30 and 60 kg P2O5 ha-1) were factorialy assigned to the main plots and seed inoculation with plant growth promoting rhizobacteria in four levels (no inoculation, seed inoculation with Azotobacter chorchorum strain 5, Azosprilium lipoferum strain OF and combination of Azotobacter + Azosprilium) were assigned to the subplots. The results showed that with increasing of nitrogen and phosphor rates and seed inoculionat with plant growth promoting rhizobacteria, all of growth indices such as total dry matter, crop growth rate, relative growth rate and leaf area index were increased. Also, seed inoculation with both of Azospirillum and Azetobacter in all of sampling stages in growth indices was more than control (no seed inoculation). Maximum grain yield and leaf dry weight were obtained in highest rates of nitrogen and phosphor fertilizers with seed inoculation with both of Azosprilium and Azotobacter and minimum of they were obtained in no application of them.

To investigate the effect of sowing date and seeding rate on Triticale growth characteristics, a field experiment was carried out in the Rice Research Institute of Iran, during 2008-2009. The experiment was conducted as a RCBD based split-plot design with three replications. Experimental treatments included: Four sowing date (Sept. 21, Oct. 1, Oct. 10, and Oct. 20) as main plot and four plant density (275, 350, 425 and 500 plant/m2) composed of as sub plots, respectively. Measured traits, including yield, leaf and shoot dry weight and leaf area and growth Indicators as leaf area index (LAI), crop growth rate (GGR), relative growth rate (RGR) and net assimilation rate (NAR). Results indicated that interaction of sowing date × sampling time was significant effect on height, leaf dry weight and leaf area index. The Highest values of height (120.7 cm), leaf dry weight (11.21 g.m-2.day-1) were obtained in 21 Sept. in flowering time. Shoot dry weight significantly affected by triple interaction of sowing date × seeding rate × sampling time, and maximum shoot dry weight achieved in seeding rate 200 Kg.ha-1 in 21 Sept. The highest (23.5 g.m-2.day-1) and lowest crop growth rate (11.5 g.m-. day-1) were found on 21Sept. in seeding rate (200 Kg.ha-1) and 21 Oct. in seeding rate (110 Kg.ha-1), respectively.While, the relative growth rate and net assimilation rate reached their maximum with delay in sowing date and reduced seed rate (21 Oct. and 110 Kg.ha-1). In general, according to the results, The highest grain yield (5893 kg.ha-1) was obtained in the earlier sowing date and greater quantities of seed 21 Sept. and seeding rate 200 kg.ha-1) due to higher crop growth rate, leaf area index, shoot and leaf dry weight and plant height.

In order to study effect of irrigation with wastewater and foliar application of complete fertilizer on forage yield and seed yield and yield components of foxtail millet (Setaria italica). A split plot experiment based on randomized complete block design with three replications was conducted at the Agriculture Institute of Zabol University in year 2009. Treatments included three levels of irrigation: Irrigation with well water at all stages of grows (control)، Irrigation with wastewater and tap water alternately، Irrigation with wastewater for all growing stages، as the main plot and sprayed with three levels of complete fertilizer (NATBA-LIB): Non spraying (control)، sprayed with 600 and 1200 gram of complete fertilizer in each hectare، as were the subplots. Results showed that irrigation with wastewater and complete fertilizer sprayed had significant effect on all traits except leaf to stem ratio. Furthermore، among the irrigation treatments، irrigation with wastewater in total growing period، and wastewater and tap water alternately lead to significant increase in grain yield، forage yield and yield components. Among the sprayed treatments، sprayed with 1200 gram of complete fertilizer had highest forage yield and grain.