Due to study the Effect of lead, azospirillum and humic acid on chlorophyll content, root and Shoot Dry weight in rapeseed (Brassica napus L .) an experiment was done as factorial in the basis of complety randomized design in 4 replication during 2011 at Islamic Azad university shahr-e-Rey branch. Experimental factors contains: Lead heavy metal in 3 levels (0, 250, 500 and 750 mg/Kg of soil), Azospirillum bacteria inoculation in 2 levels (0 and application) and humic acid in 2 levels (0 and 8 g/ha application). The results indicated that all factors simple effects was significant and interaction effects did not showed any significant difference. Mean comparison single effects indicated that 750 mg/kg lead application decreased chlorophyll content, root and Shoot Dry weight to 0.94 mg/g, 3.68 g/plant and 13.12 g/plant alternatively. In this case after Azospirillum application root and Shoot root Dry weight increased 10% and 6.5% consequently. The humic acid consumption increased Chl a (0.75 mg/l), Chl b (0.39 mg/l) and Chl a+b (1.12).

Expansion and economical importance of yield reduction due to iron deficiency chlorosis in the world has attracted many researchers attention. Different materials, such as iron sulfate, acidified remediation, wastes, by-products of industries, iron chelate and organic compounds, have been tested to correct iron chlorosis. This experiment studied effect of applying an iron fertilizer for corn (SC 704) consisting sulfur and Thiobacillus bacteria. Experiment was carried out in greenhouse in factorial with complete of randomized design in four replications. The first factor was two kinds of irrigation water, w1=irrigation with ordinary water of soil and water research station of Karaj and w2=irrigation with acidified water of station with pH of 5-5.2 (acidified with sulfuric acid). The second factor was seven iron fertilizer treatments, T1=Control (without iron fertilizer), T2=Iron sequestrine 138 (10 mg. kg-1), T3=Iron sulfate (110 mg.kg-1), T4=Iron oxide powder of iron ore (220 mg.kg-1), T5=T4+sulfur (250 mg.kg-1 powdered sulfur) +Thiobacillus inoculant (104 cell.gr soil -1), T6=T5+organic matter, T7=T3+organic matter. Nitrogen, potassium, triple superphosphate, Mn, Zn, Cu sulfates and acid boric was used 200, 85, 90, 10, 5, 10 and 5 mg. kg-1, respectively. In the end of experiment, Dry Shoot and root weight, iron uptake, chlorophyll Index (SPAD 502) and Fv/Fm were measured. Based on results, acidified irrigation water had significant effect on Shoot Dry weight and P and Fe uptake at five percent probability level, but had no significant effect on chlorophyll index. Effects of different fertilizer treatments on Dry weight, P and Fe uptake and chlorophyll index, against Fv/Fm, were significant on five percent level. T6 and T7 produced highest Shoot Dry weight and T2 produced the lowest. The highest amount of P and Fe uptake was belonging to T7 and the lowest was belonging to T2. The highest amount of chlorophyll index was belonging to T6. Between treatments there was no significant difference on Fv/Fm factor.

This research aimed to evaluate the effect of mycorrhizal fungi application on the physiological traits and Shoot Dry weight of the Melissa officinalis under cadmium toxicity in the research greenhouse of the Faculty of Agriculture, Yasouj University, in 2022. The experiment was designed as a factorial in a completely randomized design with three replications. Experimental factors included different cadmium levels (0, 5, 10, 15, 20, and 25 mg kg-1 soil) and the arbuscular mycorrhizal fungus Funneliformis moseae (non-application and application). Results showed that the maximum cadmium concentration led to a 27.45% reduction in relative water content and a 1.65-fold increase in MDA content. Mycorrhizal fungi also improved soluble sugars and leaf soluble protein content by 11.68% and 21.25%, respectively. Interaction of fungi and heavy metal showed that the lowest levels of chlorophyll a, b, and total were observed in the treatment with 25 mg kg-1 soil cadmium+without fungi application, measuring 0.308, 0.189, and 0.638 mg g-1 leaf, respectively. Furthermore, the highest activity of the catalase and peroxidase was observed under the treatment with mycorrhizal application + 25 mg kg-1 soil cadmium. In general, increasing cadmium levels negatively impacted the physiological traits of lemon balm, reducing Shoot Dry weight by 76.71% at the highest concentration. The highest level of this trait was achieved with mycorrhizal fungi in non-stress conditions. Therefore, the use of this biofertilizer is recommended to increase lemon balm tolerance in cadmium-contaminated soils.

Selenium (Se) is a beneficial element for plant but at high concentrations, it is toxic and causes in plant growth retardation.There is limited information about the effects of Se on salinity-induced damages on wheat. Therefore this study was carried out to investigate interaction of salinity and Se on root and Shoot Dry matter yield, activity of GPX, and concentrations and uptake of selected micronutrients in roots and Shoots of wheat. Two wheat cultivars (Triticum aestium cvs. Kavir and Back Cross-Rushan) differing in micronutrient efficiency were treated with four levels of Se (0, 20, 40 and 150 mM) and two salinity levels (0 and 100 mM NaCl). The effect of application of different Se concentrations on the Shoot Dry matter yield of wheat varied upon crop cultivar and salinity level. Application of Se at 20 mM concentration resulted in increase of Shoot Dry matter weight of ‘Back Cross-Rushan’ under salinity conditions.Selenium at 40 mM level increased Shoot Dry matter yield of Kavir cultivar at non-saline conditions. The effect of Se on activity of GPX was dependent on the wheat cultivar and Se level. In general, activity of GPX in roots of both wheat cultivars exposed to salinity stress was increased by application of 20 and 40 mM Se. Also, at saline conditions, application of 20 mM Se increased activity of GPX in Shoots of both wheat cultivars.According to the results obtained from the present study, Se nutrition had positive effects on Dry matter yield of wheat especially in salinity condition, but this effect depended on crop cultivar and applied Se concentration.

A study was conducted to evaluate the effects of moisture limitation on yield and Dry matter distribution between Shoot and root of triticale genotypes. This study was performed using a factorial experiment based on completely randomized design with four replications, in Agricultural College of Ferdowsi University of Mashhad greenhouse during 2009. Treatments were two available soil water including irrigated after 50% and 75% depletion of moisture from root zoning (as a check and moisture limitation, respectively) and four triticale genotypes (ET-82-8, ET- 82-15, Et- 79-17 and Juanillo-92). Results showed that the significant (P≤0.01) decrease in grain yield due the drought stress about 32 percent, but the effects of genotypes and interaction of moisture limitation and genotypes were not significant. Total above ground Dry weight, leaf plus Shoot and spikelet Dry weight decreased with drought moisture limitation. Moisture limitation had significant (P≤0.01) decrease in root depth about 16 percent. Also genotypes and treatment's interactions had significant effects on root depth (P≤0.01 and P≤0.05 respectively). Moisture limitation and genotypes showed significant effects (P≤0.01) but interactions were not significant. About 46 percent decrease on root Dry weight was due from moisture limitation. Experimental treatments and their interactions had significant effects on total root area. Genotypes and interactions were significant effects (P≤0.01) on root/Shoot ratio, but the effect of moisture limitation was not significant. Finally, results showed that while the ET-82-8had the better growth characters, its drought susceptibility index (DSI) was lower which indicate the lower susceptibility and high yield stability of this genotype under stress conditions.

Some beneficial soil microorganisms can reduce salt stress in many crops. Two experiments were carried outto study the effect of salinity and microorganisms on the growth characteristics of Plantago ovata Forsk. In the first experiment, tolerant species of phosphate-soluble bacteria screened in a salinity stress condition, a number of bacteria were subjected to semi-quantitative phosphate solubility test. The superior isolate was identified as Pseudomonas fluorescens based on the sequence 16S rRNA gene and other phylogenetic analysis. The second experiment was a factorial experiment in randomized complete block design with three replications. The first factor was three levels of salinity (2. 5, 5 and 10 dS/m), the second factor was mycorrhizal fungus including Funneliformis mosseae, Rhizophagus intraradices and Glomus fasciculatum, and the third factor consisted of two levels of non-bacterial and bacterial application. Shoot and root Dry weight, root to Shoot Dry weight ratio, mycorrhizal growth response and root colonization percentage were measured. Analysis of variance showed that interaction of salinity stress and mycorrhizal fungus on Shoot Dry weight was significant at level 1% probability. The interaction of salinity stress and bacteria on the ratio of root Dry weight to Shoot was significant at 5% probability level. The highest root Dry weight and root/Shoot ratio (1. 7 and 0. 9 respectively) were obtained at 2. 5 dS/m + Glomus fasciculatum treatment. The highest mycorrhizal growth response percentage was 76. 7% at 10 dS/m + Rhizophagus intraradice treatment. Comparison of the mean interactions between salinity stress and bacteria showed that the highest mycorrhizal growth response percentage was obtained in the 10 dS/m salinity + Pseudomonas fluorescenstreatment (45. 6%). The results also showed that salinity decreased the yield of Isabgol, but the simultaneous application of PSB and AMF could compensate the negative effects of salinity stress. According to the results, it is possible to use the simultaneous application of Pseudomonas fluorescens and Rhizophagus intraradices to maximize the production of Plantago ovata Forsk.

Introduction: Most plants, especially those that are native to hot areas, show signs of injury when exposed to low temperatures. Damages caused by cold stress occurs at the cell and organs level, which reflects it at the plant surface. Color change, chlorosis, general reduction of growth, cellular tissue destruction, non-absorption of nutrients, reduction of photosynthesis, non-transferring photosynthetic materials are from early effects of cold stress. Cellular responses to colds including loss of thoracic pressure, vacuolization, collapse of cytoplasmic membrane balance, cytoplasmic flow loss, and general organ dysfunction. The susceptibility of the plant to frost is different depending on the type of plant, variety, tissue morphology and other cellular characteristics, as well as the cold conditions of the period, time and cold intensity. In addition, it seems that organs of the plant have different degrees of cold tolerance. If the temperature of the aerial part is favorable, the low temperature of the root zone can be one of the factors limiting the root system and plant growth. The consumption of balanced boron content by neutralizing the negative effects of cold stress and mechanisms such as maintaining the structure of the membrane, improving and increasing root growth, increasing the synthesis of proteins needed for the plant, adjustment of stomatal movements and improved stomatal conductance, increased cell division, increased nitrogen metabolism and chlorophyll production, and its consequence was increased photosynthesis and Dry matter production, increased activity of antioxidants, calcium / potassium ratio adjustment, optimizing the transfer of calcium in the plant, adjusting the amount of water and conducting it in the cell, increasing the moisture content and relative content of leaf water, transferring soluble materials and increasing water use efficiency creates a relative resistance to low temperature stress. Although the root temperature is very effective in plant growth, it has been less attractive. Therefore, the aim of this study was to investigate the effect of low temperature of root and Shoot on the ability to restore plant growth and physiological activity in the presence and absence of boron. Materials and Methods: In order to compare the impact of sudden low temperature stress of root and Shoot on recovery of vegetative and physiological traits of tomato, a research was conducted in two separate experiments under controlled conditions in the greenhouse of Faculty of Agriculture, Isfahan University of Technology. Two experiments were factorial based on completely randomized design with 10 replications including two concentrations of boron (0, 0. 5, 1 and 1. 5 in ppm) and two temperature levels of Shoot and root sections (10 degrees’ Celsius temperature, and 11 rootstock temperatures and 22 ° C optimum and control temperatures). Indicators included photosynthesis rate, respiration rate, stomatal carbon dioxide, stomatal conductance, chlorophyll fluorescence, chlorophyll index, water use efficiency, proline, antioxidant, phenol secretion from root and leaf extracts, leaf relative water content, soluble protein concentration, ion leakage, leaf water potential, root and Shoot Dry weights and starch content. Finally, the analysis of the results was done by statistical software statistic and comparing the meanings by LSD test at 5% level. Result and discussion: The results showed that the highest amount of photosynthesis, root Dry weight and Dry weight of the aerial part were in the consumption of 0. 5 ppm of boron during abrupt stresses of low temperature on the root after the recovery period. The highest amount of stem proline and electrolyte leakage were also obtained from 0. 5-1. 5 ppm of boron consumption during abrupt low temperature on the Shoot part. According to the results, it was found that when stress has entered from the root zone to the aerial part of the plant, the plant was in the better conditions after the recovery period. It seems that when a cold stress occurred on the roots, the plant can produced more antioxidant substances, including phenol and proline, while counteracting the relative water content of the leaves were more effective with radical agents. Thus, in normal conditions, the roots of the plant operated at a lower temperature than the airspace. They also exhibited more adaptations to the lower air at the lower temperature than the air section and the plant is less damaged. At levels above the boron element due to the effect of boron toxicity and the production of excess free oxygen radicals, the plant probably suffered more severe damage than cold damage. Conclusions: Sudden low temperatures stresses on the root and Shoot had negative effects on the recovery of the vegetative and physiological traits of tomatoes. When lower temperatures were imposed on the Shoot, the plant suffered much more damages. Consumption of 0. 5 ppm of boron during cold stress by creating optimal conditions for growth also caused the relative neutralization.