Specific cutting energy variations under different rice stem cultivars and blade parameters [Variaciones en la energía específica de corte según las características del tallo de arroz y los parámetros geométricos del par cortante]
Allameh A.,Rice Research Institute of Iran |
Alizadeh M.R.,Rice Research Institute of Iran
Idesia | Year: 2016
Cutting energy requirement for rice stem is a momentous touchstone in design or optimization of cutting mechanism on harvesting machines. Various parameters such as physical and mechanical properties of a plant stem and blade shearing components are effective on the cutting energy requirement. Specifying these parameters and their impacts on the cutting energy would be especially important in the assessment of each cutting mechanism efficiency and total energy utilization. In this study, using a test-rig pendulum displacement cutting apparatus, specific cutting energy for single stem cutting of rice stem was identified. The experiments were analyzed in a factorial arrangement laid out in a completely randomized design (CRD) with three replications in order to examine the effects of rice cultivars (at four levels: Hashemi, Ali Kazemi, Fajr, and Khazar), cutting angle (at three levels: 25, 30, and 35 degrees), blade bevel angle (at four levels: 25, 30, 35, and 40 degrees), and blade speed (at three levels: 1.5, 2.0, and 2.5 m s–1) on the specific cutting energy for rice stem. The results revealed that rice cultivar and blade velocity had significant effects (P < 0.01) on the specific cutting energy. There were significant differences among cultivars in the view of specific cutting energy so that the highest and lowest values belonged to Hashemi (29.29 kJ m–2) and Khazar (16.81 kJ m–2), respectively. When blade velocity increased from 1.5 m s–1 to 2.5 m s–1, specific cutting energy raised about 77 %. Blade cutting and bevel angles were not solely influential on the specific cutting energy but they interacted with rice cultivar and impacted it. Optimum specific cutting energy obtained at cutting and blade bevel angles of 30 and 30 degrees, respectively. © 2016, Universidad de Tarapaca. All rights reserved.
Sarhadi E.,Agricultural Biotechnology Research Institute of Iran |
Bazargani M.M.,Iranian Research Organization for Science and Technology |
Sajise A.G.,International Rice Research Institute |
Abdolahi S.,Rice Research Institute of Iran |
And 6 more authors.
Plant Physiology and Biochemistry | Year: 2012
Salinity is a major factor that limits rice production worldwide. Rice is considered generally to be sensitive to salt stress during the reproductive stage. To determine the molecular mechanisms of salt tolerance at the reproductive stage, anther proteomic patterns for two contrasting rice genotypes IR64 (salt sensitive) and Cheriviruppu (salt tolerant) under salt stress were compared. Plants were grown in a greenhouse and salt stress (100 mM NaCl) was imposed at the booting stage. Anther samples were collected from control and salt-treated plants at the anthesis stage. The Na+/K+ ratio in IR64 anthers under salt stress was >1.7 times greater than that under control conditions, whereas no significant change was observed in Cheriviruppu. We also observed an 83% reduction in IR64 pollen viability, whereas this reduction was only 23% in Cheriviruppu. Of 454 protein spots detected reproducibly on two-dimensional electrophoresis gels, 38 showed significant changes in at least one genotype in response to stress. Using Mass spectrometry (MALDI TOF/TOF) analysis, we identified 18 protein spots that were involved in several processes that might increase plant adaptation to salt stress, such as carbohydrate/energy metabolism, anther wall remodelling and metabolism, and protein synthesis and assembly. Three isoforms of fructokinase-2 were upregulated only in Cheriviruppu under salt stress. This upregulation might result in increased starch content in pollen, which would support pollen growth and development under salt stress. The results also suggested that anther and pollen wall remodelling/metabolism proteins contribute to the tolerance of rice to salt stress. © 2012 Elsevier Masson SAS.
Hossain Z.,Japan National Agriculture and Food Research Organization |
Hossain Z.,West Bengal State University |
Nouri M.-Z.,Japan National Agriculture and Food Research Organization |
Nouri M.-Z.,Rice Research Institute of Iran |
Komatsu S.,Japan National Agriculture and Food Research Organization
Journal of Proteome Research | Year: 2012
Proteomics is one of the finest molecular techniques extensively being used for the study of protein profiling of a given plant species experiencing stressed conditions. Plants respond to a stress by alteration in the pattern of protein expression, either by up-regulating of the existing protein pool or by the synthesizing novel proteins primarily associated with plants antioxidative defense mechanism. Improved protein extraction protocols and advance techniques for identification of novel proteins have been standardized in different plant species at both cellular and whole plant level for better understanding of abiotic stress sensing and intracellular stress signal transduction mechanisms. In contrast, an in-depth proteome study of subcellular organelles could generate much detail information about the intrinsic mechanism of stress response as it correlates the possible relationship between the protein abundance and plant stress tolerance. Although a wealth of reviews devoted to plant proteomics are available, review articles dedicated to plant cell organelle proteins response under abiotic stress are very scanty. In the present review, an attempt has been made to summarize all significant contributions related to abiotic stresses and their impacts on organelle proteomes for better understanding of plants abiotic stress tolerance mechanism at protein level. This review will not only provide new insights into the plants stress response mechanisms, which are necessary for future development of genetically engineered stress tolerant crop plants for the benefit of humankind, but will also highlight the importance of studying changes in protein abundance within the cell organelles in response to abiotic stress. © 2011 American Chemical Society.
Nouri M.-Z.,Rice Research Institute of Iran |
Moumeni A.,Rice Research Institute of Iran |
Komatsu S.,Japan National Agriculture and Food Research Organization
International Journal of Molecular Sciences | Year: 2015
Global warming and climate change intensified the occurrence and severity of abiotic stresses that seriously affect the growth and development of plants,especially, plant photosynthesis. The direct impact of abiotic stress on the activity of photosynthesis is disruption of all photosynthesis components such as photosystem I and II, electron transport, carbon fixation, ATP generating system and stomatal conductance. The photosynthetic system of plants reacts to the stress differently, according to the plant type, photosynthetic systems (C3 or C4), type of the stress, time and duration of the occurrence and several other factors. The plant responds to the stresses by a coordinate chloroplast and nuclear gene expression. Chloroplast, thylakoid membrane, and nucleus are the main targets of regulated proteins and metabolites associated with photosynthetic pathways. Rapid responses of plant cell metabolism and adaptation to photosynthetic machinery are key factors for survival of plants in a fluctuating environment. This review gives a comprehensive view of photosynthesis-related alterations at the gene and protein levels for plant adaptation or reaction in response to abiotic stress. © 2015 by the authors; licensee MDPI, Basel, Switzerland.
Zareiforoush H.,Urmia University |
Mohtasebi S.S.,University of Tehran |
Tavakoli H.,University of Tehran |
Alizadeh M.R.,Rice Research Institute of Iran
Australian Journal of Crop Science | Year: 2010
This research was conducted to evaluate the effect of loading rate and internode position on the mechanical properties of rice straw in terms of shear strength, shearing energy, bending strength and Young's modulus. All experiments were conducted at the Department of Agricultural Machinery Engineering, Faculty of Agricultural Engineering and Technology, University of Tehran, Karaj, Iran, in October 2009. The properties were determined at three loading rates: 5, 10 and 15 mm/min and three internodes: the first, second and third internodes. The results showed that the loading rate had only effect on the bending strength. Furthermore, the internode position had significant effect on the shear strength, shearing energy and Young's modulus, and did not have any significant effect on the bending strength. The average shear strength was obtained as 12.18 MPa varying from 8.45 to 20.22 MPa, while the average shearing energy was calculated as 191.34 mJ ranging from 101.31 to 256.02 mJ. The average bending strength was obtained as 7.98 MPa varying from 6.70 to 9.81 MPa, while the average Young's modulus was calculated as 0.66 GPa ranging from 0.21 to 1.38 GPa. The information on the engineering properties of rice straw can be useful for designing the equipment used for harvesting, threshing, and processing.
PubMed | Rice Research Institute of Iran, Shahid Chamran University, Melkassa Agricultural Research Center, Atatürk University and Guilan University
Type: Comparative Study | Journal: Biochemical genetics | Year: 2016
Analysis of the genetic diversity and population structure of crops is very important for use in breeding programs and for genetic resources conservation. We analyzed the genetic diversity and population structure of 47 rice genotypes from diverse origins using amplified fragment length polymorphism (AFLP) markers and morphological characters. The 47 genotypes, which were composed of four populations: Iranian native varieties, Iranian improved varieties, International Rice Research Institute (IRRI) rice varieties, and world rice collections, were analyzed using ten primer combinations. A total of 221 scorable bands were produced with an average of 22.1 alleles per pair of primers, of which 120 (54.30%) were polymorphic. The polymorphism information content (PIC) values varied from 0.32 to 0.41 with an average of 0.35. The high percentage of polymorphic bands (%PB) was found to be 64.71 and the resolving power (R p) collections were 63.36. UPGMA clustering based on numerical data from AFLP patterns clustered all 47 genotypes into three large groups. The genetic similarity between individuals ranged from 0.54 to 0.94 with an average of 0.74. Population genetic tree showed that Iranian native cultivars formed far distant cluster from the other populations, which may indicate that these varieties had minimal genetic change over time. Analysis of molecular variance (AMOVA) revealed that the largest proportion of the variation (84%) to be within populations showing the inbreeding nature of rice. Therefore, Iranian native varieties (landraces) may have unique genes, which can be used for future breeding programs and there is a need to conserve this unique diversity. Furthermore, crossing of Iranian genotypes with the genetically distant genotypes in the other three populations may result in useful combinations, which can be used as varieties and/or lines for future rice breeding programs.
Amiri E.,Islamic Azad University at Lahijan |
Rezaei M.,Rice Research Institute of Iran
Communications in Soil Science and Plant Analysis | Year: 2010
The model ORYZA2000 simulates the growth and development of rice under conditions of potential production and water and nitrogen (N) limitations. Crop simulation models could provide an alternative, less time-consuming, and inexpensive means of determining the optimum crop N and irrigation requirements under varied irrigation and nitrogen conditions. Water productivity (WP) is a concept of partial productivity and denotes the amount or value of product over volume or value of water used. For the evaluated ORYZA2000 model in Iran, a study was carried out in a randomized complete block design between 2005 and 2007, with three replications at the Rice Research Institute of Iran, Rasht. Irrigation management (three regimes) was the main plot and N application (four levels) was the subplot. In this study, simulation modeling was used to quantify water productivity and water balance components of water and nitrogen interactions in rice. Evaluation simulated and measured total aboveground biomass and yield, by adjusted coefficient of correlation, T test of means, and absolute and normalized root mean square errors (RMSE). Results showed that with normalized root mean square errors (RMSEn) of 5-28%, ORYZA2000 satisfactorily simulated crop biomass and yield that strongly varied among irrigation and nitrogen fertilizer conditions. Yield was simulated with an RMSE of 237-443 kg ha-1 and a normalized RMSE of 5-11%. Results showed that the significant (28-56%) share of evaporation into evapotranspiration, using the actual yield (measured) and simulated water balance (ORYZA2000), the calculated average WPET was significantly lower than the average WPT: 37%. The average WPI, WPI R, WPET, WPT, and WPETQ were 1.4, 1.07, 1.07, 1.57, and 0.82 kg m-3. Results also showed that irrigation with 8-day intervals and 60 kg N ha-1, nitrogen level was the optimum irrigation regime and nitrogen level. © Taylor & Francis Group, LLC.
Mirmoayedi A.,Razi University |
Kahrizi D.,Razi University |
Ebadi A.A.,Rice Research Institute of Iran |
Yari K.,Kermanshah University of Medical Sciences |
Mohammadi M.,Razi University
Molecular Biology Reports | Year: 2012
RAPD (random amplification of polymorphic DNA) was used to distinguish the genetic diversities between two genera of Chrysopa and Chrysoperla (Neuroptera, Chrysopidae). Sixty specimens were collected in different places in Kermanshah, west of Iran. The wing venation was used for identification of each type of two genera, and the gender was determined by study of external genitalia. 20 random primers were used for polymerase chain reaction. Then, the electrophoresis was used for separation of the PCR products on agarose gel. 294 bands were amplified, which 235 bands were polymorph and others (59s) determined as monomorph. The electrophoresis results showed that the primers OPA02 with 19 bands and OPA03 with 8 bands successively amplified the maximum and minimum of bands among the applied primers. The results showed that there are maximum of genetic diversity and minimum of genetic similarity between Chrysopa male (Chrysopa-M) and Chrysoperla female)Chrysoperla-F) population, in contrast, there are maximum of genetic similarity and minimum of genetic diversity between Chrysoperla-M and Chrysoperla-F, and Chrysopa-M and Chrysopa-F. There are also more genetic similarities, between males and females of Chrysopa and Chrysoperla, than between male of Chrysopa with female of Chrysoperla or vice versa. © 2012 Springer Science+Business Media B.V.
Sabouri A.,Guilan University |
Sabouri A.,University of Tabriz |
Rabiei B.,Guilan University |
Toorchi M.,University of Tabriz |
And 2 more authors.
Australian Journal of Crop Science | Year: 2012
A mapping population consisting of 236 F2:3 families derived from the cross between two rice varieties, Gharib as female parent (with good cooking quality) and Sepidroud as male parent (with poor cooking quality) was used to analyze the quantitative trait loci (QTLs) associated with amylose content (AC), gelatinisation temperature (GT) and gel consistency (GC). A total of 105 single sequence repeat (SSR) markers were used to construct a genetic linkage map, covering a total length of 1440.7 cM of the genome in rice (Oryza sativa L.) with an average distance of 13.72 cM between markers. Twelve independent QTLs were identified using composite interval mapping. These loci consisted of three QTLs for GT, eight QTLs for AC and one QTL for GC, most of which are reported here for the first time. For GT the QTL explaining the largest proportion of variance (18.4%) was located on chromosome 6, the same locus as the alkali degeneration gene (alk). For AC, four QTLs were found on chromosome 6, one of which was located at the interval RM586-RM190 explaining 19.3% of the total variation and which should coincide with the waxy region (wx) located on the short arm of this chromosome. The results using Iranian rice cultivars, in combination with previous reports further confirmed that alk and wx regions play a considerable role in determining cooking and eating quality of rice.
PubMed | University of Mohaghegh and Rice Research Institute of Iran
Type: | Journal: Neotropical entomology | Year: 2016
The striped stem borer, Chilo suppressalis (Walker) (Lepidoptera: Crambidae), is an important pest afflicting rice in most rice-growing countries in the world. Deliniating the categories of resistance in rice genotypes under field conditions could be helpful in managment of this pest. Two categories of resistance, antixenosis and antibiosis, were examined in ten popular and diverse rice genotypes of different origin that had been selected for their resistance to the striped stem borer in a previous study. Significant differences were found between genotypes for the number of egg masses, number of eggs, preference index, larval and pupal weight, larval development time, larval survival rate, larval mine length, and leaf trichome density. It was found that the rice genotypes Novator, A7801, and Nemat had the more pronounced antixenosis-type resistance, whereas AB1 and Shirodi had better antiobiosis-type resistance. Interestingly, the rice genotype AN-74 for which Nemat is the parental line showed both types of resistance and could be effectively used in an integrated pest management of the rice striped stem borer.