Year:2006 | Volume:12 | Issue:3|Papers Count:26

One of the uses of the linear programming is in agriculture and animal husbandry, for decreasing the costs and increasing the benefit. Mostly meaty chicken’s feed has the most share in costs. In order to decrease the costs, framing the meaty chicken’ feed is very important. Original linear programming is one of the main models for decreasing the costs. However in different conditions, the director needs different choices. There for original linear programming cannot be useful .In these cases the model which would be utilized is modeling to generate alternatives (MGA). However for meaty chicken’s feed, physical needs should be noticed as well as decreasing the costs. By another words meaty chicken’s feed should be flexible. There for phase model can be used for this purpose. Because in this model decreasing the costs and flexibility of the domestic feed are both fulfilled. Comparison of the linear programming models in this study indicated that phase model decreased the costs more than the other model. Phase model decreased the costs 1.2 percent as compared with original model and 7.2 percent as compared with (MGA) model. There for framing the meaty chicken’ feed with phase model is better than the other models.

The purpose of this research was to assess the role of extension in adoption of the insurance by apple producers in the Damavand area. Population for this study was all 2118 apple producers during 2001- 2002 in the Damavand area who are involved in this business. The sample was selected through random sampling. This was a practical research with a descriptive method. A questionnaire was used to collect the data from 160 samples. From 18 independent variables, it was found that 8 of them had a positive relationship with respect to the dependent variable:1) level of education,2) work experiences,3) amount of land owned by the apple producers,4) level and amount of information available about insurance benefits,5) participation in extension training activities,6) number of visit by insurance agents,7) the age of participants, and8) extend of insurance adoption by participants.This research had indicated three major findings. It was found that the number of visiting by insurance agents, the work experiences, and awareness of insurance benefits had the highest effect on insurance adoption; while, the age of apple producers had a reverse effect in this process.

The purpose of this study was to investigate the educational needs of agricultural crop insurance specialists. The research method used in this study was descriptive and correlational. A questionnaire was used to gather data. The population of this study included all crop insurance specialists in all Provinces of Iran. The number of specialist was 126 that were working in 29 Provinces. The validity of the instrument was gained through faculty members of agricultural colleges, social welfare insurance specialists, and graduate students of agricultural extension and education. Reliability of the questionnaire was implemented by conducting a pilot test with 15 crop insurance workers (0.88). The Spearman ranking method showed that among personal characteristics at the 95% alpha level, level of education, years of experience and monthly income in regard to insurance; showed a negative significant relationship.However, a significant relationship was found between the participation in extension training classes and the level of educational needs. There was no significant relationship found between age and years of experience in extension activities. There was a positive significant relationship was found between the independent variable of various educational majors and the dependent variable educational needs. Finally the marital status and gender of crop insurance specialist had no significant relationship with their educational needs.

Careful operation of the silvicultureaml application is one of the most important methods for improving the quality and quantity of forestry that thinning is also one of the important stages in this operation. in this study, for investigation forest changes in result operation of thinning application in parrsel-28 of sery-3, two stands are selected with equal condition (which one of them was thinned and another stand was not thinned (stand control) In every stand, 30 samples of 4 areas are selected and different factors are compared after date analyzing and drawing diagram in two stand. By means of T-test it is cleared that the two stands have significant differences on the basis of diameter (2.94 cm), height (1.96 m) canopy height (1.34m) and volume (0/067m^3) variables. More light, better spacing and improved quality of forest, was caused increasing of diameter growth (%18.22), height (%14.97), canopy height (%44.22) and volume (%40.36) in the thinned stand. Diameter reduced coefficient is lower in thinned stand than another stand and it is because of the sylendric shap of the tree in thinned. Aََlso, variance investigation showed that two stands aren’t homogenized in the matter of meter, height, cannopy height, volume, diameter reduced coefficient and bole form factor scatter .mean h/d ratio in unthinned stand was greater than thinned stand that this show more unstability of unthinnrd stand. Also qualitive studies showed that trees in thinned stand have heigher quality. Investigation on the health stand showed that the present age of dried trees and wind thrown tree were respectively (%6.5) and (%4.5)_in thinned stand and (%8.5) and (%6.2) in thinned stand. Studies showed that thinning have great effects on quantity, quality and stability of stand.

The objective of this research was to study of tree species diversity based on different (dbh) classes in the Norway maple sites in Shafarood forest of Guilan. In this regards 0.5 ha lozenge sample plots has been selected (34 plots) with considering presence of Norway maple in the study forest. In each plot, inutility geographic characteristics (i.e, slope, aspect and elevation) were documented, then diameter at breast height of trees that had 10£dbh class were measured. Also, type of woody species identified and documented. Shannon-Wiener’s and Simpson’s diversity indices were used for evaluating of woody species diversity, also, evenness and richness indices were calculated. In addition, diversity was calculated in four dbh class (10-35, 35-50, 55-80, 85-120). Results showed that Shannon-Wiener’ s index and Mc Arthur’ s N1 in 35-50 dbh class (cm) had the highest value while Simpson’ s index and Hill’s N2 in 10-30 dbh class had been shown the highest value but both of Shannon-Wiener' s and Simpson’ s indices in 85- 120 dbh class had the least value. With increasing dbh classes, initially diversity of tree species is ascended then are being decreased.

The European elm scale Gossyparia spuria Modeer has been known as one of the serious pests of the elm trees. In order to study biological aspect s of this pest, the branches of elms trees of Isfahan were sampled. The type of reproduction being bisexual and also the embryonic developmental period and the interval between egg laying and egg hatching were determined. The possibility of parthenogenesis was indicated by setting virgin females on elm saplings. The results showed that this pest has only one generation per year in Isfahan with two nymphal stages. The second nymphal stage is the hibernating stage. The first nymphal stage takes six weeks while the second nymphal stage takes about six months. The second male nymphal stage emerges in the last of January to the first of February the second male nymphal stage molts to times and change to prepupa then pupa and finally a winged or a wingless adult male appear. The second female nymphal stage changes an adult after one molting. The whole females body resembles to an egg sack after mating. Thirty to forty five minute after egg laying the nymphs batch from the egg. After 30 minutes the nymphs are ready to be taken apart females body. This pest is a facultative parthenogenesis.

LD converter slag, a by-product of the iron and steelmaking industry produced in large quantities in Isfahan, Iran. The slag contains 52.8 and 2.2% (w/w) Cao and MgO, respectively. To determine the possibility using LD slag on the chemical characteristics of two acid soils from Gilan province, a study was conducted including two stages. The soil samples were collected from 0-30cm of rice field and tea orchard. First stage was incubation phase that treatments were 0, 0.5, 1, 2, 4, 8 and 16 % (w/w) of converter slag/kg soil. The slag was thoroughly mixed with 500g soil in plastic pots. Soils moisture content was adjusted to near field capacity and changes in pH, EC and AB-DTPA-extractable Fe, Mn, Zn, P and K were determined at 1, 10, 30 and 60 days. Second phase was a greenhouse study that treatments with due attention to incubation results were desined. Treatment were 0, 0.5,1 and 2 W/W and 0, 1, 2 and 4 W/W of slag in rice field and tea orchard soils, respectively. Results showed that soil pH increased with increasing slag rates. Slag increased AB-DTPA-extractable P and Mn, the increase depends on the amount of slag applied. However, the effect of slag on AB-DTPA-extractable Fe depends on initial pH, bigining decreased at the pH range of 7.4 - 8.5 and then increased at higher pH. Slag decreased AB-DTPA-extractable K especially in highly acid soil. The results of greenhous studies showed that application of 0.5, 1 and 2% W/W of slag increased the plant dry matter. Iron and manganese uptake by plant increased in soils. Application of slag increased P uptake in soils. K uptake increased in rice field soil but decreased in tea orchard soil. In conclusion seems that converter slag is suitable amendment for acid soils. It is suggested that the effect of LD converter slag on the plant growth and chemical characteristics of acid soils be studied under field conditions.

The increasing demand for food as a result of population growth has led to more pressure on the limited water resources for irrigation. For this reason, increase of yield per unit of water is more important as compared with yield per unit of land. Chemical nutrients are taken up by plant roots in solution form. Thus, an adequate amount of soil moisture is essential to facilitate this process. In Iran, fertilizers are mainly applied directly to soil. In such conditions, the yield and fertilizer use efficiency are usually low. The simultaneous application of fertilizers and irrigation water is an appropriate alternative to increase the efficiency of applied water and fertilizers. The objective of this study was to investigate the effect of various irrigation amounts on yield components, efficiency of applied water and fertilizers when used as fertigation. Consequently, a field experiment was carried out with forage corn as a complete randomized design with 20 treatments and 3 replicates. The fertilizers were applied by fertigation. Four levels of the water (60, 80, 100 and 120% treatments I1 to I4) and five rates of the recommended fertilizers (0, 60, 80, 100, and 120% treatments F0 to F4) were applied. The recommended amounts consisted of 500 kg C0(NH2)2, 50 kg KCL, 40 kg FeSO4, 40 kg MnSO4, 75 kg ZnSO4, 20 kg CuSO4, and 20 kg H3BO3 per ha. Tape irrigation was used for every treatment. The results indicated that in fertigation method, there were significant differences (p<1%) in total dry matter, grain yield and biomass between treatments. Treatment I4 with 19376 kg ha-1 dry matter, 15477 kg ha-1 biomass, and 3899 kg ha-1 grain yield and treatment I-1 with 9765 kg ha-1 dry matter, 8480 kg ha-1 biomass, and 1284 kg ha-1 grain yield had maximum and minimum yield respectively. Amounts of water used by the treatments from I1 to I4 during growing season were 6630, 7470, 8580 and 9980 m3 ha-1 respectively. Also treatment F4 with 16280 kg ha- 1 dry matter, 13756 kg ha-1 biomass, and treatment F1 with 14212 kg ha-1 dry matter, 11311 kg ha-1 biomass had maximum and minimum yield respectively. The result indicated there was no significant difference between treatment F2, F3 and F4. There were significant differences in water use efficiency (WUE) between I1 and other treatments. On the basis of dry matter WUE, biomass WUE, and grain yield WUE, treatment I3 with 2.25, 0.18 and 0.42 kg m3 and treatment I1 with 1.47, 0.13 and 0.19 kg m3 had maximum and minimum WUE respectively. The results showed that by increasing yield, water use efficiency increased and affected by fertilizers treatments. Finally, results indicated there were significant differences in harvest index (HI) between I1 and other treatments but there was no significant difference between I2, I3, and I4. Treatment I4 with 0.26 and I1 with 0.15 had maximum and minimum HI respectively. Also treatment F1 with 0.26 and F4 with 0.17 had maximum and minimum HI respectively. The results indicated that fertigation method provided the nutrients in readily available forms for plant uptake. Thus due to higher availability of nutrients, yield and fertilizer use efficiency increased, which in turn increased the water use efficiency.

The best usage of water resources must be considered as the main axis of agricultural progress. Sprinkler irrigation systems having high application efficiency may be considered to be a safe way in the direction of the best usage of water resources. In order to reach the above mentioned goal, one has to be creation about their performance in the field. The valuation of irrigation of farms is the analysis of any irrigation system which is based on measurements made in the real conditions of the fields and under the normal condition of work. Irrigation systems may or may not be well designed and properly used. The technique for system evaluation described in this study is designed for evaluation actual operation and management and for determining the potential for more economical and efficient operation. This study based on climatic condition, management, soil, and irrigation system were selected in 12 projects in Khorasan Province of Iran. At part of efficiency irrigation used from three parameters such as AE (application efficiency), AELQ (application efficiency of low quarter) and PELQ (potential application efficiency of low quarter).The minimum amount of PELQ at farm of BFV was 45% and maximum amount at THK farm was equal to 67%. Also, in this we’ve evaluated distribution uniformity coefficients like (CU, DU). Minimum distribution uniformity was related to THK farm and it’s maximum was related to MBV farm equal to 75 and 53%. One of the main reasons for low distribution uniformity is existence of wind at area and carelessness at designing. However, all results show that at executed system, maximum irrigation efficiency is 67% which have had en numerous differences with ideal efficiency (75%), so we should be more careful about drawing procedure, efficiency and exploitation management process.

The Penman Monteith equation (PM) has been proposed as the standard for estimating reference evapotranspiration. A major drawback to application of the PM is the relatively high data demand, where the method requires air temperature, wind speed, relative humidity, and solar radiation data. The number of meteorological stations where all of these parameters are measured is limited in many areas of the Iran. In this study two methods of estimating reference evapotranspiration for one of the hot and arid zone in Iran were evaluated. In first method (MPR), relative humidity and solar radiation have been derived from the maximum and minimum daily temperatures using empirical relationships, so PM requires only air temperature and wind speed for measuring at meteorological stations. Second method was using Hargreaves equation (HG). These two methods validated and calibrated using PM as a standard. The results showed that the correlation between HG and PM was not as good as expected; however, an excellent correlation was found between PMR and PM.

In order to evaluate of durum wheat genotypes growth habit in grain yield trials and determination of correlation among some agronomic traits and growth habit, this study was conducted during 3 cropping seasons (1998-2001) on 298 different durum wheat varities and lines in three cold dryland agricultural research stations (Maragheh, Heidarlo and Ghamlo). The same method in International wheat research centers was used for determination of genotypes growth habit. Means of agronomic traits (days from planting until spike emergence and maturity, grain filling period, plant height , 1000 kernel weight and grain yield) in yield trails were used for calculate of correlation among traits. Results showed that spring type genotypes were the largest number of germplasm and winter and facultative genotypes ranked after them. In Maragheh region correlation between growth habit and spike emergence date was significantly (P£ 0.01) negative (r = 0.31) and correlation between growth habit and grain filling period was significant and positive (r = 0.24). There was positive and significant correlation between grain yield, day of spike emergency, maturity, grain filling period and plant height. In Gamlo station correlation between growth habit, grain filling period and grain yield was negative (r = -0.35 and r = -0.41, respectively). Correlation between grain yield and plant height was positively significant (r = 0.39). In Heidarlo station correlation between growth habit and plant height was negative (r = -0.36) and correlation between growth habit and spike emergence date, maturity and 1000 kernel weight were positively significant (r =0.78, r = 0.79 and r = 0.56 respectively).

To review wheat and canary grass inter-species and intra-species competition as well as dynamic analysis of their interference, an experiment was conducted in 2001-2002 at the research station agricultural of Ghaemshahr Azad university The experiment included 45 plots and each plot had various more or less density of phalaris minor in constant relatively density of Triticum aestivum, During growth season, for all plots within a quadrate by 50×60 centimeters, leaf area, dry weight and plant density, also at the end of season, those characters, were measured separately, At the end of the experiment, wheat single plant biomass Neperian logarithm model was used to estimate the interference, The results showed that during the growth season, wheat intra-species competition was more than interference with canary grass(Interspecies synergism), During the most part of the growth period, canary grass had an stimulating role on wheat, but as compared with the effects of wheat intra-species competition, this role appeared to be less, At end of the growth stages, canary grass role in interference with wheat had been explained as a competition and this subject is confirmed to the superiority of the relative competition effect and its high leaf area index.

An experiment was conducted to investigate the effects of gossypol in cottonseed meal (CSM) on some hematological parameters in Atabay rams. Eight Atabay rams of 2 years old with an average body weight of 58±6.09 kg, were used. Rams were divided in two control and treatment groups (N=4).The isocaleric and is nitrogenous diets were calculated for the control and treatment groups contained 10% soybean meal (SBM) and 15% CSM (containing 850 ppm free gossypol) respectively. Blood samples were collected for 12 consequent weeks to measure Erythrocytes Osmotic Fragility and Plasma Level of Potassium. It also collected 3 times within 12 weeks of experiment to measure Plasma Levels of Testosteron, Red and White Blood Cells Counts, Hemoglobin Concentration and Hematocrit. The data were analysed with the Nested Design using SAS software. The results showed that differences between the control and treatment groups for blood parameters were not significant (P>0.05) except Erythrocytes Osmotic Fragility (P<0.05). Erythrocytes Osmotic Fragility was more in the treatment group than in control group (6.01 g/lit vs 4.97 g/lit). Because increase in Erythrocytes Osmotic Fragility Preceds other known gossypol- induced physiological changes, therefore it can be concluded the feeding Atabay rams with cottonseed meal containing relatively high levels gossypol, should be limited for long time use.

In this study a single – equation model have used for estimating newsprint demand function in Iran. The data are annual newsprint consumption per capita as dependent variable and national income with a lag; printing and writing paper price and real newsprint price are used as explanatory variables for the time period 1981 to 2003. Functional form of the model is a Linear Regression Model (Log-Log). After specification the model Ordinary Least squares (OLS) have used for estimation coefficients of the model. Finally the income elasticity is estimated at 0.05 level 1.82 and the value of price elasticity is estimated - 0.46. Both income and price elasticity are statistically significant at 0.05 level. In addition, statistically significant coefficient of printing paper price indicates that with increasing its price, per capita consumption of newsprint will decrease up to 0.33 percent. By this model the per capita consumption of newsprint in Iran in year 2007 is estimated 2.56±1.15 kg.

This study with purpose to investigate the anatomical and chemical properties in stem of colza (Brassica napus) was arranged. Sample selection of used tests was Ocapi that was prepared from center of modification of seeds, Karaj County. For study the anatomical and chemical properties of colza fibers, used the TAPPI standard. Colza fiber length, diameter, lumen diameter, cell wall thickness was measured at 0/82 mm, 30 mm, 18.2 mm, and 6 mm respectively. Chemical composition was as follow: cellulose 43 %, lignin 19.3%, extractive 6.5% and ash 7.3%. The slenderness ratio, flexibility ratio and raunkel ratio are calculated in the colza from one site 27.33, 60.67, 65.93. With regard to fiber properties this type of non-wood and comparison to Oder raw material, because of this, using rind from colza in papermaking can be useful.

In this study, the tracheid length and physical properties of wood in plantation cypress (Cupressus sempervirens L. var. horizontalies (Mill) Gord) were analysed in radial and longitudinal directions of the tree stems. Three plantation cypresses were cut down in ramsar’s forest (North of Iran ) and from each tree, three disks were selected at intervals of 20 cm, 130 cm and mid-length of the tree trunk. The testing samples were prepared from these disks for measuring the main properties such as, tracheid length, dry specific gravity, critical specific gravity, maximum moisture content and total volumetric shrinkage based on the ASTM standard, and the data in two radial and longitudinal directions in the trunk were analyse statistically. The result of this study shows that tracheid length of plantation Cypress wood in are increased from pith to bark and in axial direction, were decreased from bottom to top. The variation patterns of the dry specific gravity and critical specific gravity in radial direction, were increased from pith to bark and axial direction were decreased from bottom to top. Maximum moisture content in radial direction, were decreased from pith to bark and in axial direction, were increased from bottom to top. The variation curve of the total volumetric shrinkage in radial direction, were increased from pith to bark and in axial direction, were decreased from bottom to top.

In this research, the effect of site condition Such as altitude level, slope and edaphic condition on wood anatomical characteristics in beech tree (Fagus Oientalis. Lipsky) stands were studied.10 samples tree were collected in each site of six, across the west of Noor City (Galandrood Forest) with three different altitude levels (700, 1000 and 1500 m). From each tree, one sample was collected by sounding bit at the breast height and then in laboratory biometric coefficients of 30 fibers were estimated in Franklin (1938) method. The effect of altitude level on wall thickness was significant (with a maximum in 700 m), but there was not any relationship between site conditions and the other biometric coefficients.

Wheat flour proteins linked together with disulfide bonds and making gluten structure. (reducing agent) Cause to increase sulfidryl with effecting on sulfidryl bonds and reducing them which distinguished effect on handling properties of the dough. In cooky products, reducing agents causes an increase in lamination and better make-up of bough and modifying the rheological properties of dough. In this research, wheat flour will be highlighted. Sodium metabisulfite, a reducing agent, affects on disalfide bonds in gluten. For this, it softendes gluten and modified its formability. The results of this study was showed that sodium metabisulfite increased water absorption (%) Dough development time after 10 and 20 min and reducing dough resistance and the rheological properties of wheat flour dough with high quantity and quality gluten, have been modified at level 150 ppm sodium metabisulfite.

The effect of ballast weight on tractive efficiency, slippage drawbar force and fuel consumption of the ITM285 tractor with a cabin was examined during moldboard plow operations. The speeds of 4.43 and 5.49 km/h at 3rd and 4th low gear (2000 rpm, engine rotation), respectively, were selected for the experiments. In this research a factorial experiment at 9 different levels of ballast weights (on rear axle) and two levels of speed were used in completely randomize design. Slippage was measured manually and fuel consumption was measured by constructed fuel meter. Results of this search showed that ballast and speed parameters and their interaction had significant (P<0.01) effect on slippage and fuel consumption of ITM285 tractor and ballast had significant (P<0.01) effect on drawbar force. By increasing ballast to 1150 kgf on the rear axle, fuel consumption and slippage decreased 15.6%, and 58.9%, respectively, and drawbar force increased 36.3%. Also speed did not have significant effect on drawbar force.

Moisture desorption isotherms are useful in food dehydration, storage and packaging. Because of the complex food composition, experimental measurements are necessary for prediction of the isotherms. Moisture desorption isotherms of black currant raisins were determined at 30, 40, 50, 60,70 and 80 °C, using the standard static gravimetric method developed by the European cooperation project COST 90. GAB, Smith, Oswin, Halsey, Henderson and D’Arcy-Watt equation were fit the data. The experimental data were fitted well with GAB equation at 40, 50, 70 and 80 °C and with Halsey equation at 30 and 60 °C. So, Isosteric heat of desorption data obtained at different moisture content.