Year:2005 | Volume:10 | Issue:4|Papers Count:17

In order to evaluate reaction of safflower to different intensities drought stress response of the three lines safflower at the three plant densities (13.3, 20 and 31 plant/m2) to three irrigation regimes (after 70, 140 and 210 milimeter evaporation from class A pan until physiological maturity) and one irrigation regime (after 140 milimeter evaporation until complete flowering) about number day until physiological maturity (NDM), crop growth rate (CGR) and leaf area index (LAI) at the flowering time yield, total dry matter (TDM)., Yield and grian oil rate (GOR) in the North - East of Isfahan at the a randomized complete block design with split spit- plot layout with three replications were studied during two years (2001 and 2002 seasons). Results of this experiment showed that reduced of water use in safflower canopy caused a intensive stress in safflower canopy and this stress caused NDM, CGR, LAI, TDM and GOR significantly decreased in both two years, although with increased intensity drought stress, rate reduce this characteristics was very little. On the basis of results obtained at this experiment, safflower needs enough water for maximum economic yield but this plant products good yield at the intensive drought stress.

To study the condition of 7.5 hp diesel engine of power tiller with three performances and working age, three engines were selected. One as new engine (good), one with approximately 3000 working hours (medium) and one engine with 7000 working hours (bad). These three engines were tested by an eddy current dynamometer. Energy balances of these engines by measuring different data were calculated. The statistical calculation, the energy balances were tested and approved. For fuzzy model, Mandani product with Gaussian members function, singleton fuzzyyfier and center of average defuzzifier which can shown the there engine condition were selected. Then the mathematical model of this relation was designed. To test the mathematical model, 3 parameters as input were selected. These 3 parameters were thermal efficiency, percentage of energy loose via cooling system respect to fuel consumption and one independent parameter as percentage of exhaust smoke at 2000 RPM of three engines. For fuzzy set, 27 fuzzy rules were designed. By imposing different data of these three parameters, the numerical value of mathematical model was calculated. Testing the correction of the model indicated that mathematical model for bad engine in all speeds shown correct results. In new engine, the answerer of model at 1400 RPM up to 2200 RPM was correct. In medium engine, the model was correct at 1600, 1800 and 2000 RPM and other speed the results were not correct.

In today's world a stable development of a nation that is heast harmful to natural resources and the environment is rare and is therefore of great significance all nations are attempting to establish firm foundations that will not only endure the passage of time but also become stronger day by day resulting in the progress and improvement of the society of mankind, In general to achieve such a goal, undoubtedly, it calls for strict alternation to natural resources and appropriate utilization of these resources. The present study investigates the management of natural resources in the plains of Bashabad, yazd province, in order to achieve correct scientific methods techniques that are helpful in decreasing water consumption and increasing the efficiency of water. Results of this study show that the only source of water consumption in the region is the underground water which at present has led to a full in the Hydrological level in the area due to over consumption, in such a way witnesses annually a 30cm decrease in the underground water level. In order to secure a balance between the decrease in the water level and water consumption we can apply legal measures and achieve a financial aspect by an increase in the cost of water consumed. In addition by executing proper policies for determining the costs we can achieve a stability by changing the pattern of farming (irrigation) because farmers are the significant consumers of water. Despite all kinds of limitations already in the area the amount of water consumption and the efficiency may be helpful in the efficient consumption of water and in return can be helpful in the delay of the crises in water shortage in the region which has become a threat.

The efficacy of four selected bacterial antagonist in biological control of Rhizoctonia solani the root rot agent of potato were evaluated. To isolatate the antagonists, different potato fields from both regions Ajabshire and Sarab were surveyed & sufficient rhizosphere samples were collected. The antagonistic activities of all bacterial isolates including the 4 promising strains were screened enable lab.& greenhouse condition against 3 anastomosis groups of R. solani i.e. AG-3, AG-4, AG-5. The two strains encoted BS-5&BS-1 imposed the highest inhibition effect on normal hyphal growth & sclerot in germination of R. solani AG-3. Also, both strains could significantly reduced the common rate of seedling damping off and prevent from high disease incidence & severity.

In order to screen the suitable genotypes of doubled haploid winter wheat from the view of effective agronomic traits on yield for planting in cold semiarid regions of country, a trial was planed with 39 lines of doubled haploid wheat and 2 lines of no irrigated wheat (Sabalan and zar) and the irrigated line Zarrin. The design of the trial was Rectangular Lattice and contained 3 replications that was conducted in the crop year 2001-2002. The lines and varieties were studied according to the following traits: Time to initial stem, flowering and ripening, length of flag leaf, number of tillers, number of spikes, plant height, length of spike, number of seed per spike, 1000 kernel weight, harvest index and economic yield. Analysis of variance and statistical analysis of yield and dependent traits showed that there is a significant difference among different ecotypes. Differences medicate that there is a wide genetic diversity among the mentioned traits. Grouping of genotypes for the above traits showed the genotypes that initial stem and flowers more rapidly and need less time for physiological maturity nave more yield. Correlation between necessary time for physiological maturity and economic yield was negative and significant and correlation between number of tillers and yield was positive and significant. From the view of spike length, 1000 kernel weight and number of seeds there was a significant difference amongst the genotypes. Correlation between harvest index and yield was positive and much significant (r= 0.456) and correlations between yield and 1000 kernel weight , yield and height, rooo kernel weight and height were positive and much significant (r= 0.288, r= 0.364 ana r= 0.4 respectively) that these Show the Importance of selecting genotypes with the mentioned traits. It sounds that the genotypes selected for semiarid regions should, as well as suitable yield, have the following traits: suitable height, high 1000 kernel weight, Precocious, less tillers, more fertile tillers and suitable harvest index. In tills study the genotypes 5 and 28 from the view of some traits were similar to no irrigated improved and commercial-lines that were also selected for the complementary trial. Correlation between necessary time for physiological maturity and economic yield was negative and significant and correlation between number of tillers and yield was positive and significant. From the view of spike length, 1000 kernel weight and number of seeds there was a significant difference amongst the genotypes. Correlation between harvest index and yield was positive and much significant (r= 0.456) and correlations between yield and 1000 kernel weight, yield and height, 1000 kernel weight and height were positive and much significant (r= 0.288, r= 0.364 and r= 0.4 respectively) that these snow the importance of selecting genotypes with the mentioned traits. It sounds that the genotypes selected for semiarid regions should, as well as suitable yield, have the following traits: suitable height, high 1000 kernel weight, precocious, less tillers, more fertile tillers and suitable harvest index.

Wide amplitude, distinct rings and the presence of many meteorological stations in Tehran make Fraxinus excelsior a good candidate for dendroclimatological study. After crossdating and measuring ring widths, long-term variations were removed by standardization. The correlations between indices and precipitation and temperature demonstrated that precipitation of March, April, May and June have the most positive influence and temperature of June and July have the most negative influence on radial growth. The results indicate the sensitivity of this species to high summer temperature and spring precipitation.

During 2003 faunistic and biocenotic studies were carried out on the aquatic beetles in Southern and Northern shores of Parishan lake (Fars province). A total of 18 species belonging to 5 families were collected and identified. Of these, one family, 3 genera and 10 species which are marked with an asterisk are new records for Iran. They are listed as follows:Hydrophilidae1- Enochrus hamiltoni*(Horn)2- E. bicolor (Fabricius)3- E. sayi *Gundersen4- Berosus pugnax *LeConte5- Berosus sp.near ordinatus *LeConte6- Hydrobius sp.7- Helochares sp.8- Phaenonotum * extriatum Say9- Paracymus nanus *(Fall) Dytiscidae10- Hydroglyphus hamulatus *(Gyllenhal)11-H.pusillus Fabricius.12-Hydroglyphus sp.*13-Laccophilus sp.14-Hygrotus sp.15- Agabus sp.Scirtidae*16- Cyphon* sp.Dryopidae17- Helichus* sp.Hydraenidae18- Ochthebjus sp.In this study Hydroglyphus hamulatus (Gyllenhal) was considered to be a dominant species in Parishan lake.Eight sampling code were used and the research has been done on them.In this survey, species diversity and biocenotic factors affecting on aquatic beetles were also studied.

In this study an anaerobic fungus "Caecomyces communis" was isolated from sheep and goat rumen and the morphological, enzymatic and biochemical characteristics of which were investigated. The enzymatic characteristics that were investigated consist of optimal temperature, optimal pH and enzymatic activity of three-fibrolytic enzymes carboxymethyl cellulose, avicelase, and xylanase. The amounts of enzymatic activity of these three enzymes (carboxymethyl cellulose, avicelase, and xylanase) were 0.59±0.003, 0.71±0.005, 0.93±0.007 U/ml, respectively. Optimal pH of these enzymes were 6, 6, and 5.5 respectively and optimal temperature of each of them was 50° C. Biochemical characteristics were consist of biochemical tests and investigation of possibility of growing of the fungus on various carbon and nitrogen sources (37 carbon and 31 nitrogen sources). The biochemical tests were consisting of gelatinase, reduction of nitrate, hydrogen sulfide, decarboxylase, Voges - Proskauer (VP) test, indole, phenylalanine deaminase, and urease. The responses of fungus to the biochemical tests were +, -, +, -, -, +, -, and -, respectively. The results, which obtained from the possibility of fungus growing on various carbon and nitrogen sources, indicate the patterns, which lead us toward identification of Caecomyces communis from consumption of these nutritional sources point of view.

Bottom outlet leaf gates are one of the most important structures which are used to control the flow for down steam requirements. Therefore, gate should be taken for an accurate design of such structures. The designers should check for any kind risk such as, cavitations, vibration or flow discharge through these outlet conduits. The investigations regarding the design of these structures usually fall into category of physical modeling or numerical investigations. However, the physical model studies are very expensive, and thus, numerical studies have attracted the attention of many investigators. In this paper Numerical studies based on Nabier-stokes equations were applied to predict the how domain pass a normal gate in a high pressure conduit. The model uses SIMPLE Algorithm to solve the equations and the water surface profile is determined using VOF method witch has been successfully applied for free surface flow by many investigational. The results showed a reasonable agreement with those of experiments ti predict the pressure, velocity and water surface profile.

Quantitative description of the soil water retention curve is central for many applications in agriculture. The direct measurement of this soil hydraulic function is time consuming and expensive. Alternatively, the indirect methods are increasingly used to estimate the soil water retention curve. The so-called Pedotransfer functions (PTFs) that can be regarded as a bridge between the "easily obtainable" and "difficult to obtain" properties are used as an indirect method in recent years. The objective of this study was to develop and verify some point PTFs to predict the retention curve. Also, the possibility of using geometric mean and geometric standard deviation of particle diameters instead of soil particle size distribution was investigated. Consequently, 34 soil samples were collected randomly from Karaj area, Karaj, Iran. The particle-size distributions and bulk densities of the soil samples were determined with the hydrometry and core method, respectively. The retention curve was obtained using pressure plate apparatus. The easily obtainable variables were separated into two groups: (i) particle size distribution and bulk density, (ii) bulk density, geometric mean and geometric standard deviation of particle diameters. Two point PTFs types were developed to predict six points at the soil moisture characteristics, using the stepwise regression method. The results indicated that the second specified variables (ii) can better predict the soil moisture characteristic at -30, -100, -300, -500 and -1500kPa. The geometric mean and geometric standard deviation of particle diameters appeared to have larger influence to predict the water contents at drier parts of the retention curve than the soil bulk density. This can be related to the fact that at near saturation the water content is mainly affected by total soil porosity, while at lower water contents particularly near the FC up to the wilting point, the soil moisture is more influenced by geometric pore size distribution.

To introduce productive and new forage plants, a 3-year research (1379-1381) was conducted to evaluate the effects of Plant density on quantitative and qualitative characteristics of Forage Sorghum in second cropping. The test was carried out as split plot in R.C.B.D (Randomized Complete Block Design) with 4 alterations in Khoy agricultural research Station. The density of 200, 250, 300, 350 thousand shrubs per hectare was considered as primary factor level and the kinds of Speed feed, Sugargraze and Jumbo as secondary factor levels. The result of analysis of compound data variances showed that an increase in shrub density on the surface unit leads to the reduction of plant paw and the thinned stalks. Also, a decrease in space between plants and their density-350,000 per hectare- affects in the increase of plant height, leaf surface indices and the proportionate increase of leaf to stalk. On the whole, maximum cropping yield was attained in dry and wet silage and protein in the surface unit with 350,000-plant density. Of the samples experimented, Speed feed yielded the maximum cropping of wet and dry silage of 75 and 14.5 tons per hectare respectively. Meanwhile these figures about the other qualities of Speed feed such as: plant height, number of leaves and paws, leaf surface indicator and protein yield were higher than of Jumbo and Sugargraze. Ultimately, plantation of Speed feed Forage Sorghum with 350,000 plant density as the second cropping was recommended to Khoy Farmers.

Crook development, as one kind of warp can lead to yield and quality decrease during lumber drying. In this research in addition to study the mechanism of this kind of defect according to theoretical principals and experimental observations, utilizing an analytical mathematical model was investigated to predict the values of the crook. To do this, theory of elasticity and thermo elastic reciprocal theorem was used. Also to calculate the required force to restrict the crook, simple beam theory was applied. Results showed that differential longitudinal shrinkage on opposite edges of boards is major cause of crook and this phenomena is also a function of initial and final M.C, length and width of the lumbers. Reliability of the model estimations was compared and approved by experimental results. Finally, the values of the crook and the required force to restrict it during drying of Oak lumbers with 2.5, 3.2 and 5cm thickness and different sizes was calculated and compared with each other.

Effect of different amounts of nitrogenous fertilizer as Urea (0, 50, 100, 150, 200 and 250 kg N/ha) was studied on growth, yield and nitrate accumulation in cucumber cv. Daminos. The experimental design was a complete randomized block with four replications. Several plant and fruit characteristics consisting of number of male and female flowers, lengh and weight of plants, number and weight of fruits, dry matter percentage of fruits and plant and eventually yield of first and second grade fruits were recorded. Nitrate amout in fruits as measured for every harvest of morning and afternoon. Results showed that the number of female flowers increased with increasing the level of nitrogen. This increment was correlated positively with the increment of plant length. Nitrogen application at levels of 150-250 kg/h showed significantly higher total yield compared to that lower levels. Nitrate amount in fruit tissue was increased with increasing level of applied nitrogen and reached its highest level with application of 250 kg/h nitrogen. The level of nitrate was always higher in fruits harvested in the morning compared to those harvested in the afternoon. The level of nitrate reached its toxicity threshold in treatments of 200 and 250 kg/h nitrogen when harvested in the moning but for afternoon harvest it reached toxicity threshold when 250 kg/h nitrogen was applied. It can be concluded that nitrogen can be applied at 200 kg/h if it is supposed to be harvested in the afternoon but only 150 kg/h nitrogen can be recommended if it is supposed to harvest in the morning.

Diallel crosses involving 8 Bread wheat cultivars were used to determine mode of inheritance, gene action, general and specific combining abilities and effect of different environmental conditions on genetic parameters for harvest index and biological yield. Parents and F1S were evaluated in a randomized complete block design with 3 replications and two stress and non-stress conditions. Data were analized according to method of Hallauer and Miranda and model 2 of Griffing's method 2 for diallel crosses. The Jinks-Hayman analysis used to estimate broad and narrow-sense heritabilities and mean degree of dominance. Significant differences accrued between parental lines and between crosses for both traits in two environments. The GCA and SCA mean of squares, MSgca/MSsca ratio and portion of additive and dominance variances indicated that additive and non-additive genetic effects contributed to the expression of biological yield and harvest index in both environments, respectively. Estimates of mean degree of dominance designated the presence of over dominance for biological yield and partial dominance for harvest index in both environments. In stress and non-stress environments broad and narrow-sense heritabilities estimates indicated low and high genetic gain of selection for harvest index and biological yield, respectively.

The purpose of this study was to measure the impact of training on rice production in Gillan and Mazandaran provinces. This research was a descriptive ex-post facto study. A questionnaire was used to collect the data. The target population for this study was 828 rice producers who participated in training courses that provided by Deputy in Agricultural Research & Training Organization. From this population 120 were selected through random sampling method. Out of 15 independent variables, it was found that six of them had a relative positive relationship with the following dependent variable:a) The income of rice producers;b) The amount of land using for producing rice;c) Number of visit to the farms;d) Application of practical training;e) Adaptability of content of training with educational needs, andf) Location of training classes.This study had two major finding: First, it was found that educational classes can be an appropriate tool for increasing rice production in Gillan and Mazandaran provinces if they hold at the appropriate time, and second is that the extension classes had not been effective in helping rice producers. Therefore, there should be an evaluation for educational classes.