Journal of Agricultural Sciences and Natural Resources
Year:2003 | Volume:10 | Issue:1|Papers Count:20

In order to evaluate the economical and biological performance potential of hull-less barley genotypes, this experiment was carried out at Gonad Research Station during (2000-2001) crop year. In this experiment, fifteen hull-less barley genotypes and hulled barley (Hordeum vulgarevar. Turkmen) were evaluated in a simple lattice statistical design with two replications. Biological and economical performance, harvest index, yield components, plant height and the other agronomic traits were determined. Data analysis of variance showed significantly difference (P<0.01) within genotypes in the traits of economical performance, plant height, number spikes per square meter and kernels per spike. Also, there were significantly at difference 5% level in the traits of dry matter production before heading stage and 1000-Grain weight. The means were compared with Tukey's method showed that genotype No.13, with 536.3 g/m2 (7.3% more than check) and genotype No11, with 255.3 g.m2 (49% less than check) produced highest and lowest economical yield, respectively. The correlation between biological performance, harvest index, dry matter production before heading stage and kernels per spike with economical yield was positive and significant.  

The aim of this paper is to determine the optimum crop rotation pattern to obtain the maximum net income and to compare it with the present conditions of farm and also to sensitively and parametrically analyze the final result of using linear programming. In order to do so, the first thing done was the determination of production capacity, kinds of expenses, net income of plant productions and crop rotations, and then solving the linear programming problem with 15 constraints including land, water, labour and the opportunity of crop planting with the respective constraints of 2, 6, 3 and 4 in the form of 12 executable crop rotations. Among these, four following optimum crop rotations were determined and selected: Land 1 and 2 (sugar beet, wheat, corn and barley), and in land 2 (wheat, fallow, barley and corn) and (sugar beet, wheat, fallow and corn). Results showed that the planted areas of land 1 and 2 and the net income of the total selected crop rotations had a respective increase of 40,3.33 and 35 percent with regard to the present condition of the land. The limitations of land 1 and 2, the opportunity of corn and the opportunity to plant sugarbeet were recognized as more limiting factors. Analyzing the sensitivity of the case showed that the net income earned by four optimum crop rotations and some other limiting factors were comparatively flexible, and with a final parametric analysis, the final result of the primary functions in comparison with the new functions was determined and approved as the optimum final result.  

Arid and semi-arid lands involve about seventy five percent of Iran. In these regions, the ground water resources are decreasing rapidly and irrigation efficiency of surface methods is low, then we have to apply the methods of irrigation that has the minimum water losses (Percolating and Evapotranspiration). Irrigation efficiency in pot and pressurized methods with correct and desire design and performance is higher than surface methods. Pot irrigation is a suitable method for this areas that has begin already applied in Yazd and Kerman provinces. In subsurface irrigation methods water is supplied directly to the root zone of crop, without wetting the soil surface. In this study, irrigation efficiency and crop yield of two irrigation methods namely pot and furrow are compared in Yazd. The planted crops were water- melon and cucumber; the research method has been taken in random plots. The results of this research show that the content of water use per unit area in pot irrigation is about 25 percent of furrow irrigation, also the yields of water - melon and cucumber crops are increased respectively 10 and 25 percent.  

A field experiment was carried out in 1999 and 2000 in Nieshabour to study of wheat (Triticum aestivum) cultivar competitiveness against Rocket (Eruca sativa) and Wild oat (Avena fatua). In this experiment seven cultivars planted with Rocket, Wild oat and without these weeds (weed free), that arranged in factorial experiment using a RCBD with four replications and 21 treatments. Time of emergence, growth habit, dry matter, stem height growth rate and time that cultivar needed to 1/2 maximum height measured. The results showed that cultivars with more tillers, minimum time requirement to 1/2 maximum height and early growth prostrate had more competitive ability against Rocket, but with Wild oat, final height was important and more reduced weed dry matter. Rocket and Wild Oat reduced wheat accumulated dry matter from beginning growth season and heading time respectively. High harvest index caused to decrease wheat competitive ability. Rocket decreased plant/m2and kernels/spike and Wild Oat decreased 1000-kernel weight of wheat.  

Melilotus officinalis L. has dormant seeds at maturity. Seed dormancy is an obstacle in controlling of this weed. The present work tries to find out the effective methods of bresking M officinalis 's seed dormancy. This study examines the effects of different compounds such as concentrated sulfuric acid (98%) in various time intervals, scarification, holing by scalpel, grinding the seeds by marblestone, wetting by boiled water in different time intervals, stratification, stratification plus concentrated sulfuric acid, and pretreatment by sodium azide, ethylene, hydrogen peroxide, potassium nitrate and gibberllic acid for breaking Mofficinalis's seed dormancy. The treatments of concentrated sulfuric acid in 30 minutes, stratification plus concentrated sulfuric acid in 15,20 and 30 minutes, holing by scalpel were the most effective treatments and caused the highest germination up to 100 percent. Other treatments in breaking seed dormancy and increasing germination did not 4ave any meaning full effect.  

The amount of total protein in seed from four varieties of Cucurbita was identified. Three varieties of these plants (ghalami, mashhadi, kaghazi) were from Cucurbita pepo and one variety (tanbal) was from Cucurbita maxima. Result showed the total protein range between 36.47-37.60%. Isolation and analysis of seed storage protein was carried out by Lamelli method and electrophoresis with polyacrylamid gel on SDS. Electrophorgram from seed storage protein showed 22 protein bands which their molecular masses were between 3.73-156 Kd and 12 protein bands are the same. Dendrogram of these 22 protein bands and similarity matrix showed similarity percent and genetically distance among them. First cluster included three varieties of C.pepo and second cluster included C.maxima, which had very low similarity in regard to first cluster and had genetically distance with three varieties of C.pepo. These result indicate that seed storage protein can be used to identify the genetically distance among varieties.  

Alfalfa is a high quality forage crop which can produce more than two tons of protein per hectar. Quantitative and qualitative forage yield of seven alfalfa cultivars were determined in an experiment in 1996-97in karaj. The design was split plot arranged in complete randomized block with replications. In each cut, total dry matter production and protein, fiber, P and Ca continents of forage were determined. Analysis based on split plot design over time showed that the effect of cutting and interaction of cutting X cultivator for leaf stem ratio, protein and fiber yield were significant. The protein yield as well as fresh and dry forage yield in pioneer 581 cultivar, Ca, P, and leaf stem ratio in Yazdi and fiber yield in pearce were higher than other cultivars. Also protien, fiber and forage continents on first harvest, P in second harvest, Ca and leaf stem ratio in third harvest were higher than other harvests due to coincidence of cutting with longer days better ecological conditions. The results of the experiment showed that: environmental conditions at harvest time have an important role on quantity and quality of produced forage. Concerning forage, protein and fiber yield, Pioneer 581, Pearce, Hamadami, Gharayonjeh and Bami were most suitable cultivars for Karaj region, respectively.  

In order to study the effects of row spacing and seeding rate on yield and yield components of promising wheat line (M-75-10), an experiment was conducted in the field of Seed and Plant Improvement Institute in Karaj region in cropping season of the year 1999-2000. A strip-plot design based on randomized complete block design was used three replications. Three row spacing (12.5, 15.6 and 18.7cm) and seven seeding rates (310, 320, 330, 340, 350, 360 and 370 seeds/m2) were randomized to the vertical and horizontal plots respectively. The maximum grain yield was obtained from the lowest row spacing (12.5 cm) due to more homogeneity in plant distribution with lower row spacing and closing to square planting. Correlation between yield and yield components showed that number of spike/m2 had the main effect on increasing grian yield and row spacing had significant correlation with number of spiklet per square unit. Number of spike per square and biomass increased with increasing seeding rate whereas spike length and number of spiklet per spike were reduced. The results showed that the best seeding rate for obtaining optium grain yield was 340 seeds per square meter.  

Oil of regular genotypes of flax (Linum usitatissimum L.) is used as drying oil in different industries, because of its high level of linolenic acid (>50%). However, oil of new genotypes of flax which have been produced by mutation breeding programs have a very low level of linilenic acid (<2%) and can be used as edible oil. Yellow seed color can be considered and used as a very good visual marker to distinguish edible-oil varieties of flax from those of industrial types which are usually brown-seeded. Although, yellow seed color could be associated with higher oil content, it may adversely affect on emergence and seed yield. The objectives of this experiment were to study genetic variation and relation among agronomic traits in brown and yellow-seeded genotypes of flax. The experiment was conducted in Isfahan University of Technology Research Farm, using a randomized complete block design with 3 replications in which the genotypes were evaluated for different traits such as emergence, height, maturity, seed yield and yield components. The results showed that there was considerable phenotypic and genotypic variation for seedling emergence, number of boils per plant and seed yield per plant among the genotypes. Broad-sense heritability was high (52-84%) for number of seedlings 1m2,days to 50% emergence, days to maturity and plant height in both yellow and brown-seeded genotypes. Heritability in terms of broad sense for number of boils per plant, seeds per boil, seed weight and seed yield was estimated as very low (1.99),28, 47.2 and 23.8 in brown-seeded and 28.9, 11.5,84.1 and 44.9 in yellow-seeded genotypes, respectively. Seed yield per plant showed a high and positive correlation with each of basal branching and number of boils per plant, but a high and negative correlation with number of seedlings/m2. Based on regression analysis in all genotypes and also genotypes with different seed color, the most important components of seed yield per plant were the number of boils per plant, seeds per boil, and seed weight, respectively. However, number of boils per plant contributed in the most (90%) of the variation of seed yield per plant. Path analysis revealed that the number of boils per plant had the most direct and positive effect and indirect effect through the other traits on seed yield per plant.  

This research was achieved for determining of soil effects on separation of plant types in Taleghan region with semi-arid climate. Classification of index plants was done in term of soil chemical and physical properties. Correlations were determined between canopy cover percentage and soil characteristics. 24 plant types were identified in different heights and aspects. Soil and vegetation characteristics were surveyed in different types. Correlation were obtained between canopy cover percentage and soil characteristics by simple regressiOJ1and multiple regression. Soil mentioned properties were gravel percentage, lime percentage, acidity, electrical conductivity, depth, organic matter, Nitrogen percentage, Potassium content and texture. Comparison between plant types was done by Analysis of Variance, Duncan Multiple Range Test and cluster variations of canopy cover percentage were surveyed in various aspects and by Analysis of Variance. Significant correlations between soil and plant were observed in 12 range plants. Three range plants hadn't any significant difference with measured factors in soil. Soil characteristics can separate different plant type, although correlations aren't 100%. More over, the result showed relationship between soil factors and plants is one of the important factors in canopy cover percentage on different elevations and aspects.  

To determine the chemical composition and nutritional value of six dominant range plants species: Medicago sativa, Onobrychis sativa, Medicago polymorpha, Hordeum bulbosum, Poa bulbosa and Dactylis glomerata at three phonological stages (vegetative growth, early flowering,full flowering); the samples were collected in Yekkeh Cheanar area. The samples were dried under room condition and then calculated percentage of dry matter. Then samples were ground by Mullinex grounder and chemical analysis were done according to AOAC method. The results obtained from chemical analysis were analyzed by using factorial experiment at randomized complete block design. The results showed that Medicago polymorpha had a maximum crude protein; ash; total digestible nutrient, calcium, digestible energy ranged from, 15.5%-20.80%, 14.53%-17.67%, 60.32%-70.79%, 1.18%-1.32%, 2.39-3.02 Mcal/kg respectively; and a minimum crude fiber, ADF, NDF and gross energy ranged ITom15.67%-28%, 22.33%-31.33%, 31.66%-45.33%, 3.4-3.5 Mcal/kg respectively at the three phonological stages. The maximum crude fiber, acid detergent fiber, neutral detergent fiber, phosphor ranged ITom,32.66%-39.33%, 39.33%-50.67%, 54.66%-69.67%, 0.3%-0.36% respectively; and minimum crude protein, total digestible nutrient, digestible energy ranged from, 7.37%-13.54%, 38.08%-51.12%, 1.77-2.08 Mcal/kg respectivily at the three phonological stages related to Dactylis glomerata, Medicago sativa at the three phonological stages haf a maximum amount gross energy (3.95-4.28 Mcal/kg). Under the condition of this study the content of crude protein, ether extract, digestible dry matter, digestible energy and metabolizable energy decreased as the plants mature; but, at the other hand the content of crude fiber, ADF, NDF increased with the maturity.  

A survey has been conducted on the metazoan parasitic infections of juvenile sturgeons in southeast of Caspian Sea during 1997-1999.239 specimens were obtained from beach seines in Miankaleh Peninsula and Gorgan - rud estuary. Ten and eight parasite species were recovered from 126 juvenile A. persicus and 113 juvenile A. guldenstaedti respectively. Anisakis larvae with 19.8% and 13.3% had the highest prevalence of various parasites were observed in A. persicus and A. guldenstaedti respectively, too. Age and diet of samples determined. Prevalance, frequency, range, intensity and dominant of parasites were determined. Effects of seasons on parasitic infections and parasitic infection in different ages of fishes were studied. The result of this study was compared with results of other investigators in other parts of Caspian Sea.  

The Anaesthetic effects of clove oil (Eugenia caryophyllata) were studied in fingerlings of Persian sturgeon (Acipenser persicus) of three weight groups consisting.of specimens weighting 4.25 g (9-11 cm), 3.33 g (7-9 cm) 1.89 g (5-7 cm). The anaesthetic and recovery times were considered in different concentrations of25-120 ppm under farm conditions including: pH=8.31 and temp. =22º C as well at pH= 5.88 and water temperature of 21º C and 23ºC. Also the effects of long-term non-feeding (48 hours) and long-term exposure of fish into clove oil solution (3-30 Minutes) were studied. The results showed that concentration of 75 ppm and 12ppm was the suitable dosages of anaesthetization and sedation. Anaesthetic concentration and time of exposure had significant effect on anaesthetic duration (P<0.05) but not on recovery time in all conditions. Also pH, temperature, weight and duration of non-feeding had significant effect on anaesthesia and recovery time in some cases.  

Organic and commercial phosphorus fertilizers are used in today's agriculture to maintain a high level production of agricultural crops, while in most watersheds controlling of phosphorus is a very important issue. Because of the contribution of phosphorus to water quality deterioration, the environmental scientists are very concerned about the increasing of phosphorus concentration in standing waters. The blossom of the algae and other aquatic plants is related to different nutrient concentration e.g. phosphorus in their media, however, the role of phosphorus as a key element in eutrophication of the surface water and lakes is well documented. Four soil groups and sediment samples from the St. Esprit watershed of Quebec, Canada were amended with 50, 100, and 500 mg P kg-1soil as KH2PO4.The relationship between water-extractable P, WEP, (soluble phosphorus) and available P, MHШ, (Mehlich #3) was determined for water-soil ratios of 100:1, 200:1, and 500:1. Soluble P for these water-soil ratios were measured by method of Murphy and Riley after 4 hours shaking. The 4 hours shaking of the samples were based on the laboratory experience that more than 90% of the water-extracted phosphorus was released after 3 hours shaking for all the samples. Therefore, the shaking time for release of soluble P was set at 4 hours. Mehlich#3 extractable P was also determined in soil and sediment samples. There was a linear relationship (linear isotherm) between the logarithm of soluble and Mehlich#3 extractable P at different water:soil ratios for all soil and sediment samples from the watershed. Therefore, the equation of these isotherms could be used in mathematical models such as ANSWERS, an event based model, for prediction of soluble P transport from this watershed.

The effect of flushing by the use of a supplementary feeding and oestradiol benzoat on reproductive efficiency of Zel ewes was compared. 200 ewes of 4-5 years old were randomly allocated into four groups in lowland pasture of Golestan province. Four treatments were applied to these four groups of ewes as follows: Group one (control), group two using nutritional flushing, group three using nutritional flushing plus one injection of 0.5 ml oestradiol benzoat hormone, group four using one injection of 0.5 ml oestradiol benzoat hormone. Each ewe in groups two and three was given 300 grams of a mixed concentrate ration, containing barley grain 60, wheat bran 10, beet pulp 30 percentages for 28 days prior to tupping. For each group of ewes two teaser rams were used to detect heat. The results showed that ewes were received oestradiol benzoat with or without nutritional flushing, had signs of estrous after 24 hours of injection. Ninety- two percentages of ewes in group two showed signs of estrous after 14 days of flushing. The amounts of non-return rates of ewes were 74, 98, 96, and 86; and lambing percentages of ewes were 84, 120, 128, and 102; and twinning percentages of ewes were 11, 22, 32 and 16 respectively for four groups of ewes. In conclusion, the use of nutritional flushing plus injection of oestradiol benzoat for inducing estrous synchronization and increasing reproductive efficiency can be suggested for Zel breed of sheep.  

This experiment was carried out to study the effect of feeding different levels of colostrum on the activity of adrenal and thyroid glands during the first week of life were investigated. 18 calves were allocated in three groups of 2, 1 and 3(n=6). Calves were fed colostrum twice daily for 3 days (group 2), or colostrum only as their first meal (group 1), or they received only milk replacer, no colostrum (group 3). Postprantial plasma gloucose concentrations on day 2 were higher in group 2 than two other groups (P<0.05). Plasma concentrations of T3 and T4 decreased during the first week of life in all groups. Circulating concentrations of plasma cortisol had reducing pattern in all animals, but on days 2 and 7 plasma cortisol levels were higher in group 3 than two other groups (P<0.01).  

In this experiment, effect of three kinds of oils; sunflower, soy and solid (hydrogenated) soy cotton seed oil on the semi fried French fried potatoes varieties (Cosima, Draga and Folva) of Golestan province, were studied. The results showed that dry matter, fat, sugar percentage and peroxide value were used as an oxidation reaction phenomenon, no significant difference (P>0.01)was observed between partially fried French fried potatoes processed with sunflower oil and solid ( hydrogenated) soy cotton seed oil. But between these same two oils and soy oil, a significant difference was noticed. Since the peroxide value, as mentioned earlier is an established criterion for measuring the degree of oxidation reaction of oil, so partially fried French fried potatoes processed with soy oil with the least degree of oxidation, have high quality. In view of oil absorption, a significant difference was observed among the partially fried French fried potatoes samples processed with all three oils used. Thus potatoe samples fried with sunflower oil, contained the lowest degree of oil absorption. Regarding dry matter, a significant difference was noticed among the partially fried french fried potatoe processed with these oils and potatoes samples fried with solid soy cotton seed oil contained the highest amount of dry matter. The sugars also determined, and no significant difference was noticed between these potatoe samples fried with soybean oil and solid (hyrogenated) soy cotton seed oil. However, when the same two poato samples compared with potatoe samples fried with sunflower oil, a significant difference was observed ,and potato samples processed with sunflower oil contained the least percentage of sugar. Since, oil absorption was used as a major determination criterion for measuring quality of semi fried French fried potatoes, so under the condition of this experiment, potato samples fried with sunflower oil at zero (fresh) and one month storage, contained the least oil absorption, it is supposed to have a better quality respectively.  

Pathogenicity of twenty-six isolates of ascochybta blight fungus, Ascochyta rabiei, from 16 provinces of Iran was evaluated using 16 differential cultivars in greenhouse condition. Variance analysis revealed that affect of isolates; cultivars and their interaction were significant. Isolates were grouped on the basis of pathogenecity pattern, virulence intensity and cluster analysis. Pathogenecity test identified three races (R1, R2, R3) and two pathotypes (P1, P2), but on the base of virulence intensity all the isolates were divided into three pathotypes (P1, P2. P3). Cluster analysis distinguished two virulence groups with the averages 6.21 (highly virulence) and 3,87 (weakIy virulence). In the study, a new method was used for pathotyping of isolates. At first, the cultivars divided into six resistance levels then all the isolates resolved into six Pathotypes (P1. P2, P3, P4, P5, P6). The new method had more ability for grouping of isolates. The   results showed pathotype 6, includes three isolates from Tabriz, Markazi and Hamedan provinces, is very aggressive and all the used cultivars are sensitive against it, Thus it looks that it is necessary to design programs for breeding resistance lines in different areas.