The changes in Root length density (RLD) of rainfed fig trees due to supplemental irrigation were studied during two growing seasons in Estahban, southern Iran, with objective of finding out the optimum position, time, and amount of supplemental irrigation. Irrigation position treatments were: (1) In a micro-catchment close to tree trunks; (2) Inside the tree canopies (1-1. 1 m from tree trunks); and (3) Outside the tree canopies (2. 1-2. 2 m from tree trunks). Irrigation time treatments included: (a) In early spring and (b) In mid-summer; and the treatments of irrigation amount were: (i) No supplemental irrigation (control), (ii) 1, 000, and (iii) 2, 000 L per tree. Results showed that the highest RLD in different irrigation amounts occurred at 15-45 cm depth during late winter and late spring. However, during summers, the high RLD occurred 15 cm lower at 30-60 cm depth. Irrigation water treatments of 1, 000 and 2, 000 L per tree increased RLD values by 11. 3 and 19. 3%, respectively, in late spring and 10. 5% and 14. 7%, respectively, in late summer, compared with the rainfed treatment. Whereas this increase generally occurred in the wetted area; supplemental irrigation out of tree canopy could develop the Root horizontal extension to a greater distance. Lower temporal variation in RLD profile was obtained for depths deeper than 75 cm, which was in agreement with soil water content variations. Supplemental irrigation applied out of tree canopy with 2, 000 L per tree (200 m3 ha-1) during early spring is recommended to improve Root development of fig trees in drought prone rainfed areas.

Plant Root system has an important role in crop production. It is well known that Roots assist as an anchor to the plant and water and nutrients absorption which are necessary for plant survival and growth. In order to evaluate the effect of phosphate solubilizing bacteria and mycorrhizal fungi under different levels of phosphorous chemical fertilizer application, an experiment was carried out in factorial arrangement using a completely randomized design with three replications at Agricultural Research Station of Ilam University in 2015. Experimental factors consisted of two dry land wheat cultivars (Keras Sablan and (Saji) and chemical and biological fertilizers (1-without application of phosphorous, 2-100% phosphorous chemical fertilizer, 3-pseudomonas putida(strain 168), 4-Funeliformis mosseae, 5-P. putida + F. mosseae, 6-P. putida + F. mosseae + 50% of phosphorous chemical fertilizer, 7-P. putida + 50% of phosphorous chemical fertilizer and 8-F. mosseae + 50% of phosphorous chemical fertilizer). Results showed that fertilizer sources had significant and positive effect on Root system in wheat cultivars and seminal Roots number, nodal Roots number, sub-nodal number, seminal Roots length, nodal Roots length and sub-nodal Roots length, Root length density, Root specific density, Root volume density and Root area density increased significantly. Maximum Root number and Root length (13. 3 and 397. 2 cm), Root length density (0. 75 cm Root/cm-3soil), Root area (150. 3 cm-2), Root volume density (0. 010 g Root fresh weight) and Root area density (166. 7 cm-2/g) observed in Saji cultivar ×F. mosseae +50 % of phosphorous fertilizer treatment but the minimum Root system characteristics detected in Keras Sablan cultivar× control treatment.

Introduction: Biofertilizers play a crucial role in soil fertility by dissolving stabilized phosphates and producing the nutrients needed for plant growth in the soil. One of the most important soil microorganisms is mycorrhizal fungi. Mycorrhizal fungi, with their extensive hyphae network and increasing the level and speed of Root uptake, increases the plant efficiency in nutrients, especially inactive elements such as phosphorus, and improves plant growth. Mycorrhiza fungi increase nutrient uptake of plants due to stimulation of Root formation and subsequent increase in Root level through the production of auxin and gibberellin hormones. By extending the Root system, mycorrhizal fungi increase the total absorption surface of inoculated plants and thus improves crop plant access to water absorption. Considering the important and critical role of Roots in crops, having sufficient information and understanding the morphological characteristics of the Root system is important. Therefore, this study was conducted to investigate the role of the Root system in the presence of mycorrhizal fungi in new barley cultivars in the Ilam region in rainfed conditions. Materials and Methods: In order to investigate the effect of inoculation with mycorrhiza fungi on the Root system of barley cultivars in rainfed conditions, a factorial field experiment was carried out based on a randomized complete block design with three replications in the farm station of Sarablah Agricultural Research Center during 2019-2020 cropping season. Experimental treatments were including barley cultivars (Mahali, Mahour, Khorram, and Fardan) and fertilizer sources treatment including control (without fertilizer), 50% P fertilizer, mycorrhizal fungi (Glomus mosseae, Glomus etunicatum, and Rhizophagus irregularis), mycorrhizal fungi+50% P chemical fertilizer and 100% P chemical fertilizer. Root-related characteristics were measured inside the field at the pollination stage using a metal cylinder with dimensions of 30 cm in length and 2 cm in width, which had been pre-designed by hand. To measure grain yield after removing the marginal effects (50 cm from the beginning and end) were recorded for each plot. Statistical analysis of the data of this research project was done by SAS software, means were compared by Duncan’, s multiple range test method, and graphs were prepared by Excel software Results and Discussion: This study showed that the interaction between cultivar× fertilizer sources was significant on the characteristics of rainfed barley Roots. So that the maximum Root length (76. 6%), Root volume (75. 7%), Root area (73. 3%), Root length density (76. 8%), Root tissue density (89. 9%), Root-specific mass (65. 7%), and Root surface area density (70. 6%) was obtained from Fardan cultivar×mycorrhizal fungi+50% P chemical fertilizer compared to control treatment (without fertilizer source). It seems that the presence of mycorrhizal fungi has caused changes in Root morphology so that the spread of mycorrhizal mycelium related to the internal tissues of the Root has increased Root length. Conclusion: The results of this study showed that the use of mycorrhizal fungi increased Root system and Root morphological changes in new barley cultivars. What is clear and has been mentioned in the reports of other researchers is that the mycorrhizal fungi can gain maximum use of moisture and nutrient uptake by creating a strong Rooting system in the host plant from the rhizosphere. Recent research has shown that Fardan cultivar in the presence of mycorrhiza fungi had maximum Root length, Root volume, Root area, Root length density, Root tissue density, and finally, Root surface area density, and when no fertilizer source was used, a large reduction in the Rooting system was observed in all cultivars. Therefore, among the cultivars used, Fardan cultivar with coconsumption of mycorrhizal fungi and 50% of P fertilizer can cause the development of Root system and ultimately increase grain yield in the region under dryland conditions.

IntroductionAmong the nutrients used by the plant for the growth of nitrogen due to its participation in the structure of proteins, amino acids, coenzymes and nucleic acids are the main factors involved in plant growth and fertility. In recent decades, a group of soil bacteria in the rhizosphere has been introduced as plant growth-promoting bacteria that have been able to improve crop growth. In addition to the positive effects on soil properties, these bacteria are economically and environmentally beneficial and a good alternative to chemical fertilizers. Azotobacter and Azpirillum are the most important Plant growth-promoting rhizobacteria (PGPR) in plants that, in addition to bio-stabilizing nitrogen, produce growth-promoting hormones such as auxin, gibberellin, and cytokines. Modification of Root system architecture by PGPR implicates the production of phytohormones and other signals that lead to enhanced secondary Root branching and development of the Root system. Since accessible water is the main factor limiting growth in rainfed agriculture, so one of the ways to improve nutrition and plant growth is to use PGPR. Therefore, this study was carried out on the role of Azospirillum + Azetobacter on Root traits of new wheat cultivars in Ilam province.Materials and MethodsIn order to investigate the effect of growth-promoting bacteria on Root system criteria in wheat under dryland conditions, a field experiment was carried out as a factorial arrangement based on a randomized complete block design with three replications at the farm station of Sarablah Agricultural Research Center during 2019-2020 cropping season. Experimental treatments include different wheat cultivars (Sardari, Karim, Koohdasht and Rijaw) and treatment of different fertilizer sources, including control (without fertilizer treatment), 50% urea chemical fertilizer (50% of required), Azospirillum + 50% 50% urea chemical fertilizer (50% of required), Azetobacter + 50% N fertilizer, Azospirillum + Azetobacter + 50% urea chemical fertilizer (50% of required) and 100% urea chemical fertilizer (100% of required). Each experimental plot consisted of eight planting rows with a row spacing of 20 cm and a length of 4 m. Nitrogen fertilizer (120 kg.ha-1) was applied at planting and stalking stage based on soil test. Phosphorus fertilizer was applied from triple superphosphate source at the recommended rate of 50 kg.ha-1at planting time. In this study, Root length, Root fresh and dry weight, Root volume, Root surface, Root diameter, specific Root length, Root length density, Root specific mass, Root tissue density and Root surface area density were evaluated. Experimental data were analyzed using SAS statistical program. Comparison of means were done by Duncan test and graphs were drawn with Excel software. Results and DiscussionThe results of this study showed that the interaction between cultivar × fertilizer sources was significant in Root characteristics of dryland wheat, so that the maximum Root length (115.6 cm), Root volume (13.3 cm3), Root surface (137.2 cm2), specific Root length (46.9 cm Root length.g-1 DW Root), specific Root mass (0.0045 g of DW Roots.cm-3 soil volume), Root length density (0.214 cm Root length.cm-3 soil volume), Root tissue density (32.4 g Root.cm-3 soil volume) and Root surface area density (127.5 cm2.cm-3) was obtained in Rijo cultivar × Azospirillum + Azetobacter + 50% 50% urea chemical fertilizer (50% of required) compared to control treatment (without fertilizer sources). ConclusionThe results showed that due to the lack of rainfall in most rainfed fields of the province and also due to the positive effect of fertilizer biofertilizer in maintaining soil moisture, improving the physical and chemical quality of soil, to achieve proper grain yield in rainfed conditions of biofertilizer with chemical fertilizer Used nitrogen. In this study, it was observed that in the combined system of biochemical and chemical fertilizers, the Rooting system increases so that the maximum Root length, Root volume, Root area, Root-specific volume, Root length density, Root tissue density and Root surface density was observed from Rijaw cultivar × Azospirillum + Azetobacter + 50% N chemical fertilizer.  Bacteria increase plant growth by affecting the plant by improving physiological and biochemical conditions to increase resistance to adverse environmental factors in rainfed agriculture. Therefore, the results of this study can be concluded that in rainfed conditions where the intensity and fluctuations of rainfall are not predictable, having a strong Root system can greatly reduce the harmful effects of water deficit against environmental stresses in the region and cause an acceptable increase in the yield of dryland wheat grain.

Distance-based clustering methods categorize samples by optimizing a global criterion, finding ellipsoid clusters with roughly equal sizes. In contrast, density-based clustering techniques form clusters with arbitrary shapes and sizes by optimizing a local criterion. Most of these methods have several hyper-parameters, and their performance is highly dependent on the hyper-parameter setup. Recently, a Gaussian density Distance (GDD) approach was proposed to optimize local criteria in terms of distance and density properties of samples. GDD can find clusters with different shapes and sizes without any free parameters. However, it may fail to discover the appropriate clusters due to the interfering of clustered samples in estimating the density and distance properties of remaining unclustered samples. Here, we introduce Adaptive GDD (AGDD), which eliminates the inappropriate effect of clustered samples by adaptively updating the parameters during clustering. It is stable and can identify clusters with various shapes, sizes, and densities without adding extra parameters. The distance metrics calculating the dissimilarity between samples can affect the clustering performance. The effect of different distance measurements is also analyzed on the method. The experimental results conducted on several well-known datasets show the effectiveness of the proposed AGDD method compared to the other well-known clustering methods.

In a pot culture experiment, the Root length density, potassium concentration in crop, and total K uptake by wheat (Triticum aestivum var. HD 2285) at different growth stages (CRIS-Crown Root Initiation Stage, MTS-Maximum Tillering Stage, FLS-Flag Leaf Stage and DFS-Dough Formation Stage) were determined. Wheat crop was grown in 72 pots containing 4.5 kg of three types of soils, namely Alfisol, Vertisol, and Inceptisol. Pots were divided into two sets, that is, with 50 mg kg-1 K as basal and another 50 mg kg-1 was top dressed at 45 days after sowing and without potassium. Optimum doses of N, P and other macro-and micro-nutrients were given to the crop. At different stages of wheat growth (22, 41, 69, and 87 days after germination), the shoot was harvested and the soil in the pot was screened carefully under moist condition to collect total Roots and measuring the Root volume and mean Root diameter. Using Root volume and mean diameter of Root, total Root length and then Root length density were calculated. Results show that the wheat dry matter yields increased gradually with crop age and it was more in Inceptisol followed by Vertisol and Alfisol. Potassium deficiency decreased total Root length (TRL) and Root length density (RLD) in the last stages of wheat growth particularly in Vertisol and Alfisol. Potassium concentration in wheat at different stages of crop growth was found to be less in Alfisol than in Vertisol and Inceptisol. At different stages of wheat growth, potassium uptake (mg pot-1) was found to be less in Alfisol than in Vertisol and Inceptisol. The uptake values increased sharply with the age of the crop up to 69 days after germination (FLS), but the rate of potassium accumulation showed a gradual decrease thereafter, in soils, which received optimum amount of potassium.

Short-term changes of soil bulk density (BD), cone index (CI), corn (Zea mays L.) Root length density (RLD) and Root surface area (RSA) under different management regimes was studied. The interaction effects of tillage (no-till, NT; chisel plow, CP; and moldboard plow, MP) and composted cattle manure applications [0, 30, and 60 Mg (dry weight) ha-1] on BD, CI, RLD and RSA were assessed in a split-plot design under corn plants. The BD and CI were determined to depth of 22.5 and 30 cm, respectively. The RLD and RSA were measured to depth of 50 cm. Tillage methods and manure applications had significant effects on BD, CI, RLD and RSA. The MP system had higher values of RLD and RSA with lower values of both CI and BD. The NT system resulted in lower RLD, and higher CI and BD. The increased BD and CI of the topsoil in the NT treatment probably restricted Root growth. Adding manure to the soil significantly increased RLD and RSA in the order of 60>30>0 Mg manure ha-1. There were also significant differences in CI and BD among the manure treatments. The positive effects on CI and BD of manure applications are attributable to manure incorporation in soil structural improvement. The results indicate short-term positive effects of manure application on soil physical properties under moldboard and chisel plowings in the semi-arid regions. Our findings indicate short-term beneficial effects of manure application on corn Root characteristics while combined with the tillage systems.

Background & Objective: Auxin producing plant growth-promoting bacteria can prevent the entry of heavy elements such as cadmium into the aerial section of plants. This issue was investigated using Bacillus atrophaeus in the presence and absence of tryptophan by inoculation of rye under cadmium contamination. Materials and Methods: This experiment with 12 treatments including two bacterial levels (inoculation with B. atrophaeus and non-inoculation), two levels of the tryptophan amino acid (application and non-application) and three cadmium levels (zero, 50 and 100 mg. L-1) was performed as hydroponic culture with rye culture in factorial experiment with randomized complete design. Results: The results showed that the co-application of tryptophan with bacterial inoculation of rye as a superior treatment reduced the entry of cadmium into its aerial section by 53 and 37% compared to the control treatment respectively at 50 and 100 mg. L-1 of cadmium. Also, the highest amount of cadmium accumulation in the Roots, especially at the level of 100 mg. L-1 cadmium, was 2 times higher than the control treatment. The study of Root characteristics also showed that there is the highest correlation between Root cadmium concentration and Root surface density and Root surface density characteristics (r2=0. 87). Conclusion: In order to reduce the entry of cadmium into the shoots of rye, B. atrophaeus can be inoculated alone or with the addition of tryptophan. Due to the high accumulation of cadmium in the Roots, this compound can be used in the cadmium phyto-stabilization process.

In this paper, we prove the strong uniform consistency and asymptotic normality of the kernel density estimator proposed by Jones for length-biased data. The approach is based on the invariance principle for the empirical processes proved by Horvath. All simulations are drawn for different cases to demonstrate both, consistency and asymptotic normality and the method is illustrated by real automobile brake pads data.

Background: Determination of working length has great significance in Root canal treatments. For this purpose, analog radiography has been replaced by digital radiography. Despite numerous studies, there is still no accurate information about the resolution of these images.Objectives: Theaimof this study was to assess the accuracy of working length determination in Root canal treatment using different algorithms in digital radiography.Materials and Methods: Using an analytical-diagnostic method, an access cavity was prepared in 36 mandibular and maxillary premolar teeth. A file # 15 was inserted into the canal of each tooth until the tip of the file was observed, then the files were retracted 0.5 mm. The teeth were then placed in an acrylic block, and finally, a radiograph was taken of the blocks. Thereafter, the file in each canal was taken out and measured using a digital caliper. The obtained measurement was the real length of the file. The saved images underwent modifications using different algorithms of image processing. The working length was observed on a monitor under standard conditions. Data were analyzed by t- test using SPSS (ver.17).Results: Based on the findings of this study, no significant difference was observed between the main image, the images processed with the emboss, enhancement, sharpen, and negative algorithms, and the actual file size regarding the means of error. None of the indices had a statistically significant difference with the actual file length (P>0.05).Conclusions: According to the results of this study, the accuracy of the file length in improved digital images showed no significant difference in comparison with the actual file length.