The effect of mycorrhizal species on the growth, essential oils, yield and morpho-physiological parameters of Lemon Balm (Melissa officinalis L.) under water-deficit conditions in Tabriz region

Two years experiment were conducted in 2016-2017 as split-plot based on randomized completely block design with three replications to morpho-physiological responses of Lemon Balm (Melissa officinalis L.) plant to mycorrhizal fungi species treatments (control, Rhizophagus intraradices, Funneliformis mosseae, Glomus hoi and combined application of all three species) under different irrigation regimes (irrigation after 70, 100, 130 and 160 mm evaporation). In results, the highest oil yield was achieved in irrigation at 100mm+application of all three species of mycorrhizal fungi. Irrigation after 100 mm evaporation increased this trait by 33% compared to irrigation after 70 mm evaporation due to increase in essential oil percentage under dehydration conditions, however, increasing drought stress led to a significant decrease in essential oil yield. In terms of physiological parameters, dehydration led to an increase in proline content and antioxidant activates. In general and according to the results, modifying the destructive effects of water deficit stress and the use of mycorrhiza can increase the essential oil of lemon Balm. But aggravating water deficiency conditions can drastically reduce the essential oil yield. The founds could be helpful for herbal medicine researchers to achieve high-quality drugs

The effect of bio-fertilizers and a super-absorbent on the quantitative and qualitative characteristics of castor bean (Ricinus communis L.) under water-deficit conditions

The effect of bio-fertilizers and super-absorbents on the modification of water-deficit stress was studied in castor. A field experiment was conducted with a split-plot design based on a completely randomized block design with three replications. The first factor included four levels (70, 100, 130, and 160 mm of evaporation pan A Class) in the main plot; the sub-factor was the application of four bio-fertilizer treatments (Azospirillum, Citrobacter, Azospirillum + Citrobacter, and control); and the superabsorbent at two levels (superabsorbent consumption and control) as a factorial was placed in the sub-plots. With the intensification of the water-deficit stress from 70 to 160 mm of evaporation, the number of seeds per plant, the 1,000-kernel weight, and the oil percentage significantly dropped. All three bio-fertilizer treatments significantly increased the number of grains, 1,000 kernel weight, and oil percentage compared to the control. Citrobacter in all four irrigation levels significantly increased the content of photosynthetic pigments, grin yield, oil yield and proline content and decreased the catalase activity and malondialdehyde content. The application of the super-absorbent under the stress condition of 160 mm significantly raised the content of chlorophyll b, soluble sugar, grain yield, oil yield, and proline compared to the control treatment. Among the combinations of bio-fertilizer and super-absorbent treatments, the highest photosynthetic pigments’ content, grain yield, and oil yield and the lowest catalase enzyme activity belonged to Azospirillum + superabsorbent consumption. However, the maximum soluble sugars and the minimum malondialdehyde content belonged to Citrobacter + superabsorbent

The Effect of Vermicompost and PGPR on Physiological Traits of Lemon Balm (Melissa officinalis L.) Plant under Drought Stress

In this research, effect of vermicompost and plant growth promoting rhizobacteria (PGPR) on physiological traits of lemon balm under drought stress condition was investigated in year 2012 at Karaj Research Institute of Forest and Rangelands. Experiment was conducted as split-split plot in a randomized complete block design with three replications. irrigation (normal: irrigated to field capacity;  drought stress: watered to 60% of field capacity) was considered as main plot, vermicompost fertilizer (consuming 0, 5 and 10 t ha-1) as split plot and biofertilizers (Pseudomonas fluorescent, Azotobacter chrococum+Azospirillm brasilense, Azotobacter+ Azospirillum + Pseudomonas and no fertilizer) as split-split plot. Results showed that water stress significantly increased essential oil content, while decreased essential oil yield, total chlorophyll, cell membrane stability, relative water content and proline. Only relative water content and total chlorophyll were positively affected by biofertilizer application. Essential oil content, essential oil yield, total chlorophyll, cell membrane stability, relative water content and proline were significantly increased by vermicompost application, especially, relative water content increased with an increase in amount of vermicompost application, but there were strong interactions with irrigation. These interactions are important in practical use of vermicompost and biofertilizers

The Effect of Water Deficit stress on Osmotic Metabolites and Anti Oxidant System and Grain and Oil Yield of Amaranth CV. Koniz

Drought is one of the most important environmental stresses that highly affect crop growth and yield. But the response of crops to stress depending on the timing of crop growth stages is different. The purpose of this study was to investigate effect of different levels of water stress (irrigation after 50, 80, 110, 140 and 170 mm evaporation from pan) on different stages of Amaranth growth (establishment, branching, flowering and grain filling). To find the effects of water deficit stress on this plant it was decided to determine its protein percentage, oil and grain yields under drought stress. Evaluation of physiological characteristics as to the extent of osmotic adjustment and antioxidant activity was also carried out. Results showed that water deficit stress,depending on the severity and duration of stress, caused a reduction between between a minimum of 10 to a maximum of 89 percent in yield, 28 to 70 percent in harvest index, 12 to 32 percent in grain protein and 29 to 97 percent in oil yield. This indicates the high sensitivity of grain and oil yields to severe and prolonged drought stresses. Changes in osmotic substances (proline and soluble carbohydrates) showed that this crop under water stress conditions increased proline and soluble carbohydrates by 31 and 50 percents, respectively. Thus, if could be said that under severe droughts the ability of crops to cops with drought will be reduced. Similarly, amaranth, to cope with water stress, increases the amount of antioxidant enzymes like catalase, peroxidase and super oxid dismutase up to 53, 23 and 79%, respectively. Higher amount of super oxid dismutase enzyme produce as the result of drought stress may play an important role to cope with reactive oxygen species and oxidative stresses

Allelopatic Effect of Bermudagrass (Cynodon dactylon L.) Extract and Residues on Wheat (Triticum aestivum L.)

With regards to the importance and frequency of bermuda-grass (Cynodon dactylon L.) in wheat fields an experiment was conducted using factorial design in three replicates to evaluate allelopathic effects of different parts extract and residues of bermuda-grass in different concentrations on wheat germination and yield in 2008. Five levels of organ extracts as control, leaf, shoot, root and intact plant extract of bermuda-grass in four concentrations as 20, 10, 7, and 5 % were used. All extracts decreased germination and its components in wheat. The highest decreasing effect was belonged to the root and intact plant extract. In glasshouse, increasing extract concentration from 5 to 20% decreased all attributes significantly. Decrease in seed number per plant, 100-kernel weight and yield in 20% was 89, 769 and 96% less than control, respectively. Field trial confirmed glasshouse results. Generally, root and intact plant extract and residual had higher growth restriction than shoot and leaf residuals and extract on wheat attributes. In field condition, applying bermuda-grass extract decreased 71% and residual 81% of wheat yield. It may be depends on gradual leaching of allelochemicals from residuals of bermuda-grass in growth period that affect growth and yield of wheat

The Effects Foliar Application of Methanol at Different Growth Stages on Kernel Related Traits in Chickpea var. ILC 482

This research was conducted to evaluate the effects of foliar application of methanol on certain kernel related traits at different growth stages of pea var. ILC482 at the Research Station of Faculty of Agriculture in Islamic Azad University, Tabriz Branch in 2011. The study was conducted in split plot experiment based on Randomized Complete Block Design with three replications. Treatments were three levels methanol foliar application at different growth stages (vegetative, reproductive and foliar application at both two stages) which considered as main factor, six levels of foliar application of methanol concentrations: (0 [control], 5, 10, 15, 20, 25, 30%) as sub factor. Results showed that the interactions of methanol applications growth stages and its concentrations on grain number per plant, 100 kernel weight, grain yield, grain filing rate and harvest index were significantly different. Foliar application of methanol at reproductive stage decrease kernel related traits, but this application at both growth stages had positive effect on grain production and kernel related traits. This positive effect on number and 100 kernel weight were significant. The highest grain yield (2460 kg/ha) was obtained by 20% concentration of methanol at both growth stages that increased grain yield above 13.5% compared to the control condition

Evaluating of Drought Tolerance of Doubled Haploid Barley (Hordeum vulgare L.) Lines using Toleance Indices

To identify drought tolerant genotypes from 40 doubled haploid and 5 barley cultivars an experiment in a randomized complete block design with three replications was conducted both at normal irrigation and water deficit stress conditions at the Agricultural Research Station of West Azarbayjan, at Miyandoab during 1390-91 crop years. A significant difference was observed among the genotypes concering grain yield, which indicates a high genetic diversity for this trait among genotypes under study. Genotypes No. 35, 24, 21 and 3 were highest yielders in both irrigation conditions. In this study, during tolerance of genotypes under both stress and normal irrigation conditions, were evaluated by using mean productivity (MP), tolerance (TOL), geometric mean productivity (GMP), stress susceptibility (SSI), and stress tolerance (STI) indices. According SSI and TOL indices genotypes 13, 16, 1, 19, 8 and 5 were identified as tolerant genotypes to water stress. Genotypes 3, 24 and 35 were found to have highest STI, MP and GMP indices. Correlation coefficients indicated that STI, MP and GMP were the best indices to select barley tolerant genotypes to water deficit stress in this study. It was also revealed that genotypes 3, 21, 24 and 35 which were highest yielders under normal irrigation and did have the least reduction in their yield under deficit irrigation. Thus, they can be recommended to the experimental site as the top producers

Evaluation of yield traits and tolerance indices of different wheat genotypes under drought stress conditions

Drought stress negatively influences the production and productivity of wheat (Triticum aestivum L.) as one of the world’s three important cereal crops. This field experiment was conducted to evaluate the morphological, yield and physiological characters of 15 modern and elite experimental wheat genotypes under irrigation and drought stress (no irrigation from pollination until the end of the growing season) during the 2016–2017 and 2017–2018 growing seasons. The results showed that the grain yield, 1000-grain weight, harvest index as morphological traits and relative water content (RWC), total chlorophyll, electrolyte leakage, proline as physiological traits were influenced by drought stress. The grain yield of all genotypes was reduced due to the reduction of grain number per spike or 1000-grain weight in response to drought stress. The wheat genotypes showed significant differences with regards to relative water content, photosynthetic pigments, proline and electrolyte leakage under both conditions. In all genotypes, RWC and photosynthetic pigments were decreased; however, proline and electrolyte leakage were increased under drought stress. The correlation analysis revealed a positive and significant correlation between grain yield with biomass, No. grain per spike, No. spike per plant, 1000-grain weight, and main stem length. In drought stressed genotypes grain yield was significantly associated with RWC and negatively correlated with electrolyte leakage and proline content. Tolerant genotypes were selected according to results of drought tolerance indices. According to obtained data URBWYT4 with high mean productivity (MP), geometric mean productivity (GMP), stress tolerance index (STI) and harmonic mean (HARM) but relatively low stress tolerance (TOL) and stress susceptibility index (SSI) performed well in both conditions. This conclusion was supported by the results from morphological, yield and physiological traits

Effect of Bio and Chemical Fertilizers on Yield, Yield Components and Mycorrhizal Colonization Percent on Common Dill (Anethum graveolens L.)

To study the effect of biofertilizers (mycorrhiza, nitroxin and supernitroplus) and chemical fertilizers (nitrogenous and phosphorus) on yield, components of yield and mycorrhizal colonization percent on commen dill (Anethum graveolens L.) two separate two-year experiment were conducted using a factorial experiment design based on completely randomized design with three replications under greenhouse conditions at the Faculty of Agriculture, Islamic Azad University, Tabriz Branch, Iran, during 2010 and 2011. Treatments consisted of mycorrhizal application in three levels, (without using mycorrhiza as control, application of species of two mycorrhiza Glomus intraradices and G. mosseae, nitrogen-fixing biofertilizers in three levels (without application as control,applicationofnitroxin and supernitroplus) and chemical fertilizers of nitrogen and phosphorus in three levels including (zero, 50% and 100% of recommended dose according to soil analysis). The results showed that combined and simultaneous application of experimental treatments were effective on number of lateral branch, number of umbel per plant, seed yield and percent of root colonization with mycorrhiza. The combined application of biofertilizers under reduced application of nitrogen and phosphorous chemical fertilizers (zero and 50% recommended dose) affected these positively. Also, separate applications of nitrogen fixing biofertilizers, especially supernitroplus and combined application of mycorrhiza with reduced amounts of chemical fertilizers increased the number of seeds per plant against the control treatment