Showing 38 results for Rape
C. Ghobadi, M. Khosh-Khui, B.e. Sayed-Tabatabaei,
Volume 12, Issue 45 (10-2008)
Abstract
Grapevine (Vitis vinifera L.) is a clonally propagated major fruit crop. In grapevine, identification of genotypes with amplographical features is often based on mature plant characteristics that may be affected by environmental conditions. This approach lacks objectivity and reliability. Recently, molecular markers have proved to be supplementary techniques to analyze genetic diversity and examine genetic relationships existing between cultivars in a range of horticultural crops. In this study, twenty genotypes from grapevine (V.vinifera species) grown in Isfahan province were characterized by RAPD technique to understand the extent of diversity and relatedness. Fifty random primers were used for the RAPD study. Of those, twenty four informative primers which generated reproducible polymorphic bands were used for grouping the genotypes. PCR products of the genotypes’genome revealed a total of 315 bands, out of which 282 were found to be polymorphic. Average number of 13 bands was obtained per primer and the amplification produced ranged in size from 300 bp to 3000 bp. The dendrogram constructed using UPGMA cluster analysis differentiated the genotypes into two major clusters, nineteen in one group and Madar-o-Bache genotype has been placed in a separate one, indicating its high genetic diversity compared to the rest of the genotypes. Intra-clustering within cluster A grouped the genotypes in four sub-clusters as expected from their genetic background. The results of the study revealed that the RAPD technique is a relevant technique to determine genetic diversity, genomic analysis and to examine genetic relationship in grapevines.
Z Daneshvar Ran, M Esfahani, M Payman, M Rabiei, H Samie Zadeh,
Volume 12, Issue 46 (1-2009)
Abstract
The effects of tillage methods and residual management on yield and yield components of rapeseed (Brassica napus L. CV. Hyola308) were evaluated after rice harvest. The experiment was carried out during 2004-2005 cropping season in a factorical arrangement of treatments at Rice Research Institute of Iran (RRII) in Rasht, in a Complete Randomized Block Design with three replications. Treatments included tillage in three methods: a) conventional tillage b) minimum tillage, and c) no tillage, and rice residue management in two manners: a) removing residues, and b) not removing residues. Plant traits such as grain yield, oil percentage and yield, plant density, plant height, the lowest pody branch height from soil surface, number of pods per plant, plant and weed dry weight, leaf area index (LAI) and crop growth rate (CGR) were measured. Results indicated that grain yield was affected by the tillage type. Also, the effect of tillage type on plant height, number of pods per plant, the lowest pody branch height from soil surface, and oil yield was significant. The effect of residual management and residual management interaction and tillage were significant on none of the traits except for weed dry weight. Economic analysis indicated that rapeseed planting in a field with rice residual and minimum tillage had a relative advantage of less production cost in spite of nearly 15 percent yield decrease compared to other methods.
B Rabiei, M Rahimi,
Volume 13, Issue 47 (4-2009)
Abstract
Discrimination function analysis is a method of multivariate analysis that can be used for determination of validity in cluster analysis. In this study, Fisher’s linear discrimination function analysis was used to evaluate the results from different methods of cluster analysis (i.e. different distance criteria, different cluster procedures, standardized and un-standardized data). Furthermore, Hotelling T2, CCC plot and multivariate analysis of variance were used to support the results. To achieve the goals, 8 rapeseed genotypes were planted in a randomized complete block design with three replications in Rice Research Institute of Iran, Rasht, durin 2005-2006, and 14 characteristics were measured. Analysis of variance based on the randomized complete block design showed significant differences between genotypes for all the studied traits. Comparison of means between genotypes indicated that the genotype Hyola401 for grain yield and most of the measured characteristics was better than the other genotypes. Evaluation of phenotypic and genotypic coefficient of variations showed that most of the traits had high variability in the population. Discrimination function analysis showed that the Euclidean distance criterion was better than others and a desirable clustering was obtained by this criterion. Also, all of the data standardization methods produced similar clusters and were better than un-standardized data. Based on evaluation of dendrograms derived from different methods of cluster analysis determined that the UPGMA, complete linkage and Ward’s minimum variance methods were better than the other methods, and grouped the genotypes into three clusters. Fisher’s linear discrimination function analysis showed that UPGMA and Ward's minimum variance methods with clustering validity of 87.5 percent, was more suitable than other cluster analysis methods however, discrimination analysis grouped genotypes into two clusters. Tests of Hotelling T2, CCC plot and multivariate analysis of variance supported the results from the discrimination function analysis. It seems that the UPGMA and Ward's minimum variance procedures based on Euclidean distance criterion of standardized data function better in grouping genotypes, yet, the use of discrimination function analysis is recommended to confirm the results and determine the actual groups.
A Faraji, H Hatamzadeh,
Volume 13, Issue 47 (4-2009)
Abstract
Development of oil seed crops is the most important aim in our country to achieve self sufficiency. This study was conducted to assess the suitability of oil brassicas species in rain-fed warm areas of Iran. This research was performed for three years in Agricultural Research stations of Gonbad (Golestan). Twenty varieties and hybrids (B. napus, B. rapa, B. juncea ) were compared in RCBD with three replications under rain fed conditions. Each plot had 4 rows 5-meter long. Combined analysis results indicated that there were significant differences at 1% probability level among years and varieties for No. of days to maturity, No. of pod per plant, oil%, oil and seed yield. The highest seed yield was obtained in the 2nd year (2103.48 kg.ha), followed by the 1th and 3rd year (1771.50 and 1575.13 kg.ha, respectively). Namely, year environment factor had a significant effect on the rape seed product. j-98-102.51-5 (B. juncea), Alexandra and comet (Spring B. napus) showed the highest seed yield (2484, 2326 and 2290 Kg.ha, respectively). Regression analysis via step by step method explained that No. of pod per plant and oil percentage had significant positive effects (508.53 and 96.48 respectively) and No. of days to maturity significant negative effect (-78.63) on the seed yield. Factor analysis extracted four factors. Factor loading of the first three eigen values showed that the first three factors explained 98.794%, sum of variance. Rates of first, second and third factors were 45.575%, 36.816% and 16.403%, respectively. The first factor, second factor and third factor were named productivity factor (seed yield and oil yield), sink factor (No. of pod per plant), fixed capital factor (No. of day to maturity and plant height) respectively. Generally, j-98-102.51-5, Alexandra and comet varieties are advisable for Fall planting under rain fed conditions in Gonbad area because they had the highest seed yield and earliness. Also, we can introduce less No. of days to maturity (earliness) and more No. of pod per plant as select index under rain fed conditions in Gonbad.
Sh Mimohamadi, H Allahyari, M Nematolahi, A Sabouri, S Zarghami, Sh Khaghani,
Volume 13, Issue 47 (4-2009)
Abstract
The cabbage aphid Brevicoryne brassicae L. is an important pest, which attacks the rape seed and causes economic damage. In this study, effects of four different cultivars of rape seed (Zarfam, Licord, Hyola 401, and SLM046) on biological parameters and intrinsic rate of increase of B. brassicae were studied in laboratory conditions (25±1ºC, 70±10 RH and of 14:10 (L:D) photoperiod). Results showed that maximum nymphal and reproductive period, longevity of insects were found on Licord cultivar. The maximum fecundity of adult aphid was seen on Hyola 401. There was no significant difference between duration of developmental stages, and aphid fecundity on different cultivars. The intrinsic rate of increase was calculated by Wyatt & White method. Estimated intrinsic rate of natural increase of aphid was 0.316, 0.294, 0.311, and 0.289 on Zarfam, Licord, Hyola 401, and SLM046, respectively. Although the lowest intrinsic rate of increase was observed on Zarfam, statistical analysis of Wyatt & White output showed there was not any significance difference between rm on different cultivars.
B Kavoosi, S Eshghi, A Tafazoli,
Volume 13, Issue 48 (7-2009)
Abstract
Overcroping, shading and short growing season can reduce the pool of carbohydrate reserves, and consequently reduce the quality of crop in grapevines. An experiment was conducted in order to study the effects of cluster number and different levels of cane topping on balanced yield and qualitative traits of table grape (Vitis vinifera L.) cv. Askari. The design of experiment was factorial in completely randomized blocks with four replications. Factors included cluster number (Control, 25, 30, 35, 40, 45 and 50 cluster per vine) and cane topping included (Control, removal 1/4, 1/3 and 1/2 length of shoot). Results showed that decreasing the number of cluster to 25-35 per vine, significantly increased %TSS, TSS/TA and pH but with increasing cluster number, these traits were significantly reduced. Thinning treatment to 25 cluster showed significant difference from the viewpoint of %TA compared with untreated control. Also topping treatment significantly increased %TSS, %TA, TSS/TA ratio and decreased % TA compared with untreated control. Reducing the cluster to 25-45 per vine significantly increased cluster weight, however, no significant difference was observed between control and 50 clusters per vine and/or 25 to 50 clusters. Yield per vine was reduced in all treatments in comparison with untreated control. However, no difference was shown between 25 to 35 and or 40 and 50 clusters per vine. According to the results obtained, cluster thinning combined with topping can be recommended for increasing fruit quality and balanced yield of Askari table grapes in cold climate of Cisakht region.
A Shaabani, A Kamgar Haghighi, A Spaskhah, Y Emami, T Honar,
Volume 13, Issue 49 (10-2009)
Abstract
Oil seed rape (Brasica napus) is an important crop, which is cultivated in Iran for oil production. As a management practice deficit irrigation strategy is applied to cope with water shortages, especially during drought periods. This research was conducted to study the effect of water stress on physiological parameter of oil seed rape in the experimental research field of Collage of Agriculture (of shiraz university) during 2004- 2005 and 2005- 2006. Licord cultivar of oil seed rape was planted and experimental design was random block with five treatments and four replications. Treatments were full irrigation in all growth stages, water stress in vegetative stage in early spring, water stress in flowering and podding stages, water stress in grain filling stage and dry land treatment with supplemental irrigation in time of planting. Water stress caused decrease in water potential of plant, an increase in canopy temperature, and decrease in plant height especially in dry land treatment. Leaf area index decreased as water stress increased. The decrease in leaf area index was more severe in vegetative stage water stress treatment. At the end of water stress period leaf area index increased again. Rate of decrease in leaf area index at the end of the growing season was higher in grain filling stage of water stress treatment.
M. Karami Moghaddam, M. Shafai Bajestan, H. Sedghi,
Volume 15, Issue 57 (10-2011)
Abstract
In diversion flows, a portion of stream flow which enters the intake is diverted from upstream of the intake denoted by a surface and is called dividing stream surface (DSS). The amount of flow and sediment discharge entering the intake as well as design of submerged vanes to control sediment depends on determination of dividing stream width. In this study, the experimental tests were carried out at a 30 degree water intake from a trapezoidal section. Three components of velocity data were obtained for different flow conditions. Then numerical SSIIM2 model was calibrated and verified using tests data. More flow conditions such as the main channel with rectangular section were run using SSIIM2 model to get enough hydraulic data. From analysis of these datas it was found that the dividing stream width in different distances from the bed depends directly upon the diversion flow ratio. It was found that in comparison to the rectangular section, in trapezoidal cross section, the DSS dimensions are modified in such a way that its width is increases at the surface and reduced at the bed for the same flow conditions. Relations for predicting the dividing stream width and diversion flow ratio have been presented in this paper for intake from both rectangular and trapezoidal cross sections.
M. Rabiee, M. Kavoosi, P. Tousi Kehal,
Volume 15, Issue 58 (3-2012)
Abstract
To determine the proper nitrogen fertilizer rates and its application times for achieving high grain and oil yields of rapeseed cultivar, Hyola 401, a research was carried out in paddy fields of Rice Research Institute of Iran in Rasht during two cropping seasons. A factorial experiment was conducted in a completely randomized block design with three replications. The experimental factors were pure nitrogen fertilizer rate at five levels of 0, 60, 120, 180 and 240 Kg ha-1 and fertilizer application times at five levels of all fertilizer at planting 1/3 at planting + 2/3 in stem elongation 1/3 at planting + 1/3 in stem elongation + 1/3 before flowering 1/3 in 3-4 leaf stages + 1/3 in stem elongation +1/3 before flowering 1/4 at planting + 1/4 in 3-4 leaf stages + 1/4 in stem elongation + 1/4 before flowering. The results of statistical analyses showed that from amony nitrogen rates, application of 240 Kg N ha-1 and 180 Kg N ha-1 with average production of 2505 Kg ha-1 and 2596 Kg ha-1 respectively showed the highest grain yield and were in the same group. of Nitrogen application times, application of 1/3 at planting + 1/3 in stem elongation + 1/3 before flowering had the highest grain and oil yields with average of 2155.3 Kg ha-1 and 9865 Kg ha-1, respectively. Maximum oil percentage was observed in control treatment (without N-fertilizer application) and the highest oil yield was obtained for nitrogen rates of 180 and 240 Kg ha-1. Also, the highest growth period was observed for the treatment of 240 Kg nitrogen with 206.3 days. The results showed that nonsignificant difference exists between the nitrogen rates of 180 and 240 Kg ha-1 in grain and oil yields. Therefore, the rate of 180 Kg ha-1 is recomended due to less fertilizer consumption and prevention of destructive effect on the environment
Mohammad Rabiee, Masoud Kavosi, Hassan Shokri Vahed, Pari Tousi Kehal,
Volume 17, Issue 64 (9-2013)
Abstract
In order to evaluate the effect of concentration and time of foliar spraying of nitrogen fertilizer as supplemenfary to soil nutrition on grain yield and some important traits of rapeseed (Hyola401), an experiment was conducted in complete randomized block design with 16 treatments and three replications in in 2008-2009, 2009-2010 growing seasons, and in 2003-2005 growing seasons in paddy fields of Rice Research Institute of Iran (Rasht). In this experiment, nitrogen concentration (from urea source) at two levels (5 and 100.00) and application time at seven levels including 1-seedling stage: 6-8 leaves 2: beginning of stem elongation 3: prior to flowering 4: 6-8 leaves + stem elongation 5: 6-8 leaves + prior to flowering 6: stem elongation+ prior to flowering 7: 6-8 leaves + stem elongation+ prior to flowering with two control treatments including zero nitrogen fertilizer and basal fertilization as 1/3 at seed sowing, 1/3 at stem elongation and 1/3 prior to flowering stages of 180 kg pure N ha were considered. Results of combined analysis showed significant differences between the experimental treatments in most traits. Spray application of nitrogen (100.00) in stem elongation+prior to flowering stage produced maximum silique length (6.8 cm), number of secondary branch (7.1) and plant height (141.1 cm). Also, the spray application (100.00) in 6-8 leaves+stem elongation+ prior to flowering stage had maximum biological yield (10684.6 kg.ha-1), grain and oil yields (3686.2 and 1489.3 kg.ha-1, respectively) and the maturity period (202 days). Spray application (100.00) in stem elongation+ prior to flowering stage did not induce significant difference with spray application (100.00) in the three stages. Maximum oil content was observed in control treatment (zero nitrogen fertilizer) with an average of (44 %). According to the results of the present experiment, it seems that spray application of nitrogen (100.00) at final growth stage of rapeseed (stem elongation+ prior to flowering stage) increases grain and oil yields.
M. Heidarpoor, S. H. Razavian, Y. Hosseini,
Volume 18, Issue 68 (9-2014)
Abstract
The combined system of gate and weir is used for flow measurement in open channels. But in case the passing water has floating material and sediment it damages their performance and hence error of measurement will increase. In order to solve this problem, weir and gate can be combined and a concentrated hydraulic system known as weir-gate can be developed, thus allowing sediments transportation from under the gate and floating particles on weir. The principal goal of this study was to investigate the passing flow characteristics by trapezoidal weir and sharp-edge rectangular sluice gate in rectangular channel, and also suggest a discharge coefficient for combinational flow in different flow conditions. The experiments were carried out in laboratory channel on models with different geometric dimensions under various hydraulic conditions. Discharge coefficient was presented for various condition of passing flow of trapezoidal sharp-edge weir and below rectangular sluice gate using statistical analysis conducted on dimensionless geometric parameters affecting the flow. Resulting discharge coefficients were in agreement with laboratory results.
S. M. Seyedian, M. Karami Moghadam, Y. Ramezani,
Volume 21, Issue 4 (2-2018)
Abstract
The study of flow patterns in front of intake has been attracted the attention of researchers during the past decades to explore the mechanism of flow and sediment entry to the intake. In this study, the separation and stream tube dimensions were investigated in water intakes installed to rectangular and trapezoidal main channel. These researches were carried out with experimental and fluent models. The results of experimental and fluent models have a good conformity. It was found that, in trapezoidal main channel, the stream tube width decreases near the bed and increases near the surface and separation dimensions reduced and led to reduction of sediment entry and increase of efficiency
J. Khajehali, M. Kohansal, B. Hatami, M. Mobli,
Volume 22, Issue 2 (9-2018)
Abstract
The grape leafhopper, Arboridia kermanshah Dlabola (Hemiptera, Cicadellidae), is an economically important pest of most vineyards in Isfahan. The effects of two irrigation regimes [normal (100 liter/ tree/ week) and minimum (100 liter/ tree/two weeks)] seasonal population changes and the damage of A. Kermanshah as well as the percentage of leafhopper egg parasitism by Anagrus atomus were studied on five grape cultivars including Shahani, White Rishbaba, Askari, Black Rishbaba and White Yaghoti; this was done in a completely randomized blockdesign with split plots in three replications at Isfahan University of Technology in the 2005-2006 period. Adults and nymphs were assessed by weekly sampling using a vacuum insect collector (D-VAC). Non-parasitized and parasitized eggs were counted weekly by clipping three leaves from different strata of vine canopy as a sample unit, in each plot. The results showed that the leafhopper population density, damage percentage and egg parasitism in both years of study in the normal irrigation plots were higher than those with the minimum irrigation. The maximum density of adults and nymphs was observed in June and early July on the White Yaghoti. The highest egg density and parasitism were recorded in June and October-November, respectively, on black Rish-baba in the normal irrigation. The highest damage was on the white Yaghoti in August and September, and the lowest damage was on Askari and Shahani, both in the normal irrigation regime.
Gh. Safarinejadi, M. Heidarnejad, A. Bordbar, M. H. Pourmohammadi, A. Kamanbedast,
Volume 23, Issue 4 (12-2019)
Abstract
The use of free launch jets in flip bucket structures with associated submerged ponds, in the appropriate geological, and topographic and hydraulic conditions, could have significant economic and safety benefits. In this research, the downstream scour phenomenon of a flip bucket jet was investigated in free conditions, as well as in the presence of a trapezoidal and triangular slot in the coastal manner with different layout intervals at flow rate of 9, with a total of 45 experiments. The results of this study showed that the presence of the slot had significant effects on the depth and range of scour, so that the fit bucket jet with alternate triangular slots reduced the scour by about 12.7%, as compared to the no slot mode. Moreover, the maximum scour depth occurred in the bucket mode with the alternate trapezoidal slots in the more favorable interval than the rest of the models. Then, the results were compared with several empirical formulas and Veronese A relation showed closer results to the actual values.
R. Gharibvand, M. Heidarnejad, H. A. Kashkouli, H. Hasoonizadeh, A. Kmanbedast,
Volume 24, Issue 1 (5-2020)
Abstract
The flow fields over a trapezoidal labyrinth weir (two-cycle) and a piano key weir were simulated using Flow3D, studying the impact of each model on the flow field in the weirs and the coefficient of discharge in comparison with the available experimental data. Moreover, the models were investigated experimentally in a 12.5 m long, 0.3 m wide, and 0.4 m high rectangular flume under clear-water conditions. The results showed good agreement between the data from the numerical and experimental models. The piano key weirs had a higher coefficient of discharged compared with labyrinth weirs. The coefficient of discharge was observed to increase by 26 percent as the height of the PKW was increased by 50 percent (from 5 to 7.5 cm). This increase was 24 percent for labyrinth weirs.
A. Moghtaderi, E. Valizadegan,
Volume 25, Issue 2 (9-2021)
Abstract
In this study, the hydraulic characteristics of the flap gates are installed at the end of the trapezoidal channels were investigated by laboratory study. In the physical model, three trapezoidal channels and four gates with different weights were used (12 gates for three channels). Based on several experiments, equations for estimating of flow rate for each side slope (each channel) were developed using dimensional analysis. In this research, five forms of discharge-stage relationship were used to obtain relationships for each side slop to estimate flow rate, separately. The results show that none of the discharge-stage relationships forms as a single relationship for all flap gates in a certain channel are suitable for estimating discharge. But the first, second, and third forms of the discharge-stage relationship are very suitable for estimating the flow rate in a certain channel for a certain flap gate. In other words, for each gate with a specific weight, a separate (unique) relationship is obtained to estimate the flow rate in the form of the first to the third discharge-stage relationship in a certain channel. To estimate of flow rate by using the first form of the discharge-stage relationship, the maximum values of statistical parameters of RMSE, ME, and MARE, among all three channels, are 0.0001 m3/s, 0.00022 m3/s, and 0.22 percent, respectively. The values of all the above statistical parameters for the first, second, and third forms of the discharge-stage relationship are presented in the article.
J. Meshkavati Toroujeni, A.a. Dehghani, A. ٍemadi, M. Masoudian,
Volume 25, Issue 3 (12-2021)
Abstract
One of the crucial problems that exist in the irrigation networks is the fluctuation of the water surface flow in the main channel and changes in the flow rate of the intake structure. One of the effective methods to decrease these fluctuations is increasing the weir crest length at the given width of the channel with the use of the labyrinth weirs can be achieved for this purpose. The labyrinth weir is the same linear weir that is seen as broken in the plan view. In this study, a labyrinth weir with a length of 3.72 m, three different heights of 15, 17, and 20 cm, three different shapes of dentate (rectangular, triangular, and trapezoidal), and a linear weir were used in a recirculating flume with 15 m length and 1 m width. The result showed that for a given length and height of weir, with the increasing of the upstream water head to the weir height ratio (
), the discharge coefficient decreases. The results showed that by increasing weir height, the discharge coefficient decreases for a given length of the weir. Linear weir and labyrinth weir without dentate create more water depth at the upstream by 3.3 and 1.2 fold compared with dentate labyrinth weir.
F. Momeni, A.a. Amirinejad,
Volume 27, Issue 1 (5-2023)
Abstract
In precision agriculture, a productivity rating system is a significant tool to quantitatively assess soil quality. An experiment was conducted in Bilavar, Kermanshah to evaluate the spatial variability of physical indicators of soil quality of a rapeseed (Brassica napus) field. Spatial variability analysis of soil physical properties measured on a rectangular grid (100 m×100 m) was carried out using a geostatistical analyst extension of Arc-GIS software. Five physical soil quality indicators including bulk density (BD), non-capillary porosity (NCP), field saturated hydraulic conductivity (Ks), available water retention capacity (AWC), and organic carbon (OC) were determined. The physical rating index (PRI) at each sampling point was determined by multiplying the rating values for all five parameters. Results revealed that major ranges of semivariogram for Ks and AWC varied between 137-145 m and for BD, OC, and NCP they were relatively long (161-205 m). Clay and NCP showed moderate spatial dependence (0.68 and 0.28, respectively) whereas the rest of the parameters showed weak spatial dependence. Also, the correlation between PRI and the biological yield of rapeseed was fairly good (R2=0.68). Investigation of zoning maps of soil physical properties showed an increase in BD and a decrease in AWC and NCP parameters depending on changes in soil texture and organic matter content in some parts of the field. In general, the PRI index is an important tool in the quantitative assessment of soil physical conditions, and based on it and zoning maps can improve the physical quality of soil in agricultural fields.
