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Water deficit stress is considered as one of the most important factors affecting soil microbial activities in dry and semi-dry ecosystems, which reduces microbial activity by limiting access to nutrients. To evaluate the effect of water stress (30%, 50%, 70%, and 100% of field capacity), urea chemical fertilizer (100, 200, and 300 kg/ha), and the impact of biological fertilizers (inoculation with mycorrhiza alone, co-inoculation with mycorrhiza and nitrogen-fixing bacteria, co-inoculation with mycorrhiza and azospirillum, and control) on the yield characteristics of Zea mays hybrid Sc706, a field experiment was conducted as a split-split plot in a randomized complete block design with three replications in two cropping seasons (2018-2019 and 2019-2020) on a farm in Firoozabad, Fars province, Iran. Dual and triple interactions of water stress, urea chemical fertilizer, and biological fertilizer showed significant differences in all yield characteristics. In most traits, the application of urea chemical fertilizer (200 and 300 kg/ha) along with biological fertilizers (mycorrhiza-azospirillum and mycorrhiza-nitrogen-fixing bacteria treatments) produced the best results. Overall, it can be concluded that the use of 200 and 300 kg/ha of urea fertilizer along with a combination of biological fertilizers, mycorrhiza-azospirillum and mycorrhiza-nitrogen-fixing bacteria, can be suitable options for improving the yield and morpho-physiological characteristics of corn under regional conditions. [ABSTRACT FROM AUTHOR]

Salvia mirzayanii Rech. & Esfand is an Iranian endemic plant belonging to the Lamiaceae family which has many pharmacological effects including antioxidant, anti-cholinesterase, antimicrobial, anticancer, anti-inflammatory and enhancing cognition and memory. It is considered as an endemic species of Iran, that is in danger of extinction. The bulks aromatic plants come from wild populations whose essential oils compositions as well as their biological properties are severely affected by the geographical location Therefore, the aim of the present study is to provide more information on the variation of essential oil composition of S. mirzayanii collected from four different geographical regions. The aerial parts of four populations of S. mirzayanii were collected from different natural habitats of Fars province in southwest of Iran. Chemical composition of S. mirzayanii were isolated by hydrodistillation using clevenger type apparatus and analyzed by GC-FID and GC/MS. The major compounds in four populations were a-terpinyl acetate, Eudesm-7(11)-en-4-ol, bicyclogermacrene, d-cadinene and 1,8-Cineole in four populations. Polyphenolics content were identified by HPLC analysis. Predominant phenolic constituents in all extracts were chlorogenic acid, vaniline and rosmarinic acid, p-cumaric acid, trans-ferulic acid and quercetin. The DPPH radical inhibition was measured by using a micro-plate reader. The best antioxidant activity was related to ecotype3 with 1281.48 µg/mL and the highest amount of total phenol is related to ecotype1 and ecotype4. [ABSTRACT FROM AUTHOR]

One of the sustainable and the most effective methods for controlling wind erosion is protecting the ground surface by mulching and vegetation cover. This study was done to assess the effect of organic and inorganic mulches and also compaction levels on soil properties and growth characteristics of caper plants, as one of the important shrubs to combat desertification in hot-humid areas. Results suggested that sugarcane bagasse and palm waste compost mulches significantly increased soil organic carbon (OC), nutrients (available nitrogen, phosphorus, and potassium), and moisture, and decreased soil electrical conductivity (EC), pH, and temperature. Petroleum mulch increased soil penetration resistance (69.50 kPa) and temperature (25.50). Petroleum and cement-slag mulch, and also their combination (petroleum-cement mulch) decreased soil moisture to the minimum extent. For either compaction level, using petroleum mulch increases penetration resistance. Compaction decreased soil moisture by 0.96% and increased total neutralizing value (TNV) and bulk density (BD) by 1.52% and 0.31 g cm−3, respectively. For either compaction level, soil porosity increased with the application of sugarcane bagasse mulch and palm waste compost. Using sugarcane bagasse mulch and palm waste compost increased stem length, leaf number, above ground and root weight, and shoot to root ratio of caper plant. Soil temperature (a = −0.70, R2 = 55.70%, P ≤ 0.001), EC (a = −0.87, R2 = 42.49%, P ≤ 0.001) and penetration resistance (a = −1.32, R2 = 17.03%, P ≤ 0.01) decreased with increasing soil moisture. BD (a = −1.20, R2 = 37.08%, P ≤ 0.001) decreased with increasing soil OC. Findings suggested the significant effect of organic mulches on improving some soil properties and growth characteristics of caper plants. [ABSTRACT FROM AUTHOR]

In order to study the application of mathematical models in the analysis of the effect of planting density and weed interference on agronomic traits of different rapeseed genotypes, indicators including physiological feature, morphological feature, components and compounds of components of experimental rapeseed genotypes, in the terraces, which were broken twice, in the form of pilot plan of blocks, complete randomized, with 3 replications was conducted in Fars province (Darab city, Farrag district) in 2012-2013 (two years). The results of stepwise regression of grain yield (as dependent variable) on 12 agronomic traits were presented for two years. The results confirmed that pod weight and 1000-grain weight could well predict performance changes. In order to interpret the relationships between traits and grouping them, factor analysis was used based on these relationships. Factor analysis was carried out using principal components method on the traits studied in this experiment and the factors were given to Vermax 1 for better justification. In this analysis, the three main and independent factors justify a total of 88.48% of the total variance. [ABSTRACT FROM AUTHOR]

Precise and appropriate management of farmland for a cotton crop to reach the highest water use efficiency with a low water supply and an acceptable yield is required in arid- and semiarid regions. This study in Iran aimed to find the most appropriate concentration of jasmonic acid (JA) and the best stage for application to cope with any negative impacts of water deficit stress. A split-plot factorial experiment based on a randomized complete block design with three replications was used in 2 consecutive years (2016-2017). Two irrigation intervals of 10 and 20 days were used, with four concentrations of JA (0, 25, 50, and 100 mg L-1) and applications at three crop stages (vegetative, reproductive, and vegetative and reproductive together). The final results showed that the 20-day interval significantly decreased relative water content, the quantity of cotton, cotton yield and its related traits including boll number per plant, the 1,000-seed weight, seed cotton yield, lint yield, and lint percentage. It also increased the content of proline and soluble sugars. The 50-mg L-1 concentration of JA applied at the vegetative-reproductive stages appropriately mitigated the negative effects of water deficit. These results are of practical application for farmers in arid- and semiarid regions with low water supply when irrigating cotton lands in order to reach an acceptable cotton yield. [ABSTRACT FROM AUTHOR]

This study was performed to the environmental evaluation of auxin and plant growth promoting rhizobacteria priming on yield and yield components of wheat under drought stress. Experiment was conducted as a Split plot in RCBD design with 3 replications. Main factor included drought stress (irrigation on base of 25, 50 and 75%FC) and sub plots were inoculation at 4 levels (control, azotobacter, pseudomonas and a combination of two bacteria), also sub plots were auxin priming at 4 levels (0, 1, 2 and 4 mg.L-1). According to results, application of drought stress led to the reduction grain yield, so, the 50% and 75% water discharge treatments led to 9% and 37% the reduction of grain yield as compared to control, respectively. In relation to bacteria treatments, highest grain yield (4.35 t/ha) obtained by azotobacter inoculation. In relation to auxin application, the 4 mg.L-1 treatment led to 6%the increase of grain yield as compared to control. Highest means of grain yield (3.25 t/ha) under 75% discharge water observed by azotobacter inoculation. We concluded that priming with auxin and rhizobacteria, plays an important role in the induction of tolerance to drought and overcome limitations created by the drought stress on wheat. [ABSTRACT FROM AUTHOR]

This study was performed to the environmental evaluation of auxin and plant growth promoting rhizobacteria priming on yield and yield components of wheat under drought stress. Experiment was conducted as a Split plot in RCBD design with 3 replications. Main factor included drought stress (irrigation on base of 25, 50 and 75%FC) and sub plots were inoculation at 4 levels (control, azotobacter, pseudomonas and a combination of two bacteria), also sub plots were auxin priming at 4 levels (0, 1, 2 and 4 mg.L-1). According to results, application of drought stress led to the reduction grain yield, so, the 50% and 75% water discharge treatments led to 9% and 37% the reduction of grain yield as compared to control, respectively. In relation to bacteria treatments, highest grain yield (4.35 t/ha) obtained by azotobacter inoculation. In relation to auxin application, the 4 mg.L-1 treatment led to 6%the increase of grain yield as compared to control. Highest means of grain yield (3.25 t/ha) under 75% discharge water observed by azotobacter inoculation. We concluded that priming with auxin and rhizobacteria, plays an important role in the induction of tolerance to drought and overcome limitations created by the drought stress on wheat. [ABSTRACT FROM AUTHOR]