Agricultural Sciences and Technology
Year:2002 | Volume:16 | Issue:1|Papers Count:25

The following steps were used to evaluate the amount of free gossypol in cottonseed meal (CSM) samples of Khorasan province. Samples of (1-2 kilograms of) CSM were taken from three oil extraction factories in Nyshabor and one in Mashhad. Mashhad cottonseed meal (MCSM) had more crude proteion (%29.3) and less crude fiber (%22.5) than others, therefore this meal was used to study the broiler chicken performance. Total and free gossypol content of CSM samples were determined by HPLC. For determining the effect of dihydrated fero-sulfate (DFS) in lowering free gossypol the following treatments were used in the lab: 1 - Control MCSM. (with zero DFS) 2 - MCSM with added DFS (as equal amount of free gossypol) 3 - MCSM with added DFS (as equal amount of total gossypol). The broiler performance were studied by a factorially arranged (3 x 4) completely randomized design experiment consisting of four levels of MCSM (0,5,10 and 20% of diet) and three levels of DFS (zero, equal to free gossypol and equal to total gossypol). All the nutrients density based on metabolizable energy were the same in all treatments. Each treatment was consisted of 6 replicates of 8 day-old broiler chickens. Free and total gossypol in Mashhad cotton seed sample were determined to be 0.023% and 0.077% respectively. Addition of DFS equal to free gossypol, lowered free gossypol to %0.0001 and addition of DFS to total gossypol lowered free gossypol to zero. Different levels of DFS and MCSM did not have any significant effect on daily feed intake, live weight weight gain, feed conversion and mortality of broiler chickens up to 56 days of age (P>0.05).

s experiment was conducted at Kateholieke University of Leuven (Belgium) in order to determine the effect of controlled atmosphere storage on ethylene production and ripening of Jonagold apple during storage period. Apples were collected from commercial storage of Belgishe-Fruit-Veiling (B.F.V.) which had been under atmospheric controlled condition (I-2°C, 02%1, C02%1.5 and C2H4500 to 80000 p.p.b.) during three times storage period (1st, 6th and 15 th week). The analysis for each storage period was done on 1st and 7th days after storage for measuring of ethylene production, C02production, flesh firmness and colour. With respect to statistical analysis, there was significant correlation between flesh firmness and ethylene production, flesh firmness was lower with increasing ethylene production. Ethylene production had no effect on C02 production. Results showed that loss of flesh firmness of apple during atmospheric controlled storage seems to be related to high ethylene concentration in storage rooms at first weeks of storage period. In conclusion loss of flesh firmness by the red side of apple was more than the green side during storage and shelf life period.

In order to investigate the effects of different tillage methods and residue management on agronomic criteria on sesame (Sesamum indicum L.), an experiment was conducted during grawing season of 1375-76 and 1376-77. This experiment was on the basis of split - split plot design with 4 replications. Treatments were different combinations of two levels of residue (without residue and 3 ton of residue / ha): three levels of tillage methods (Conventional tillage, minimom tillage and no tillage): and 3 rotation systems; (1) wheat-maize - wheat sesame, (2): wheat-sesame-wheat - maize. (3) wheat - fallow - wheat - sesame. Cultivar used was local Sirjan population. Yield of sesame was significantly affected by tillage methods in all 3 rotations: however yield in conventional tillage was lower than other tillage methods. Yield was increased with no residue treatment in all rotations. Number of branches / plant was reduced only in rotation (2) with conventional tillage. Number of capsules plant was reduced in conventional tillage. Number of seeds/capsules and 1000 - seed weight were not affected by tillage methods and residue application in all rotations; but harvest index was affected only in rotation (3). Yield was not also affected by rotations. Protein and oil content of seeds were not affected by tillage methods. residue management and different rotations. Micro-organisms population and soil bulk density were not also affected by different tillage and residue treatments in any rotation. Protein and oil content of seeds were not affected by tillage methods, residue management and different rotations.

In order to dairy cow diet formulation, the In situ protein degradation characteristics of some feedstuffs (barley grain, wheat bran, suyal, beet pulp, soybean meal. Cottonseed meal and corn silage) was determined. In addition, in the second step, these parameters were compared to AFRC standard Tables in lactating cow diets containing alfalfa hay or alfalfa hay and silage (50:50). The results indicated that the cows fed with diets based on the present degradability coefficients had higher milk yield (kg/d), milk protein (g/d), milk NPN (g/l) and milk dry mater (g/d) (p<0.05), when compared to the other groups. It is also noted that there is not significant differences between diets containing alfalfa hay or alfalfa silage (50:50).

The purpose of this researsh was evaluating the effects of land consolidation policy on rice production and its costs in Haraz River Basin which choose 209 case from 3 village of this region by Two Stage Cluster Sampling Method (TSCS), production function and third degree function of cost in 1998.Theresultsshowthat land consolidation policy increases production of qualified long grain variety (Tarom) and high yield long grain variety (Nemat) by 23.8 and 15.8 percent, respectively and has decreased production costs of these varieties by 35.2 and 18.6 percent, respectively.

Epiphytic and endophytic colonization of some Pseudomonas syringae pathovars in leaves, stems and roots of tomato (Lycopersicon esculentll/l1cv. Cannery Row) was studied. Surface disinfestation with chloroform revealed that the chemical is a potent surface sterilant but would not penetrate into the natural openings present on plant tissue surfaces. Hence chloroform appeared to be harmless to massive bacterial populations present in such area as stomata and lenticels. This chemical was found suitable for surface disinfestation in studies dealt with endophytic colonization. Plasmid pLA LacZ was introduced via triparental pairing into wild type and hrp mutant strains of p.s. pv syringae, p.s. pv tomato and p.s. pv phaseolicola. Tamato cv. Cannery Row seedling were inoculated with the wild type and mutant strains of P.syringae. Microscopic examination thin sections of the inoculated but symptomless tomato organs and tissues revealed that bacterial colonization occurred mostly endophytically. P.syringae cells were observed among paranchyma cells and in vascular tissues of inoculated plants. These sites appeared to be more suitable for colonization P.syringae.

Animal fat (AF) and cotton seed oil (CSO) were blended in the proportions (AF: CSO) of: (1) 0.25: 0.75, (2) 0.5: 0.5. (3) 0.75: 0.25. The three blends together with the AF, CSO, fish oil, two heated vegetable oil and a by product of vegetable oil refining were each included at 3, 6,9 precent in to a basaldiet. Fats were anlayzed for most chemical parameters(fatty acid profile, gross energy, dry matter, peroxid value, saponification and unsaponification index and iodin index). The experimental diets were evaluated for true metabolisable energy corrected to zero nitrogen (TMEn) with 4 replicates of two adult single comb white leghorn cockerels per cageusing force feeding method. There was no significant depaliure from linearity in the response of dietary TMEn to added fat. Synergism, as drived from the differences between determined and calculated TMEn values, was detected with two fat combinations (1 and 2). For all fats and oils, the best regression equation could be derived (R 2 =0.976), based on 4 chemical parameters (oleic acid, acid value, Saponification index and unsaponification index).

Due to increase of resistance in German cockroach (Blattella germanica) to insecticides, the effects of some organ phosphorus and pyrethroid insecticides were evaluated in dormitories of Ferdowsi University of Mashhad. These places were frequently under intense pressure of different insecticides. The tests was carried out on two growth stages of German cockroach (first instar nymphal of 3-5 days aged and adult females of 1-5 days after laying the ootheca). Six different insecticides (Permethrin, Cypermethrin. Lambda cyhalothrin, Diazinon, Prymphos methyl and Chlorpyriphos) each in three levels of concentrations (0.003, 0.006 and 0.009) were used. The results were compared in a factorial experiment based on randomized complete block design with 4 replications. The comparision mean of mortality tests indicated that lambda cyhalothrin caused the highest motality on the nymphs and adult females in the least of test time and in the lowest concentration. The m0l1alityeffects of chlorpyriphos, prymphos methyl and diazinon were relatively satisfactory, but effects of permethrin and cypermethrin were not desirable. In most cases the nymphs showed more susceptibility to insecticides than the adult females. Knock-down tests by pyrethroid insecticides indicated that lambda cyhalothrin had the highest effect and cypermethrin the lowest effect on nymphs and adult females of German cockroach.

Ascochyta blight is the most widespread and destructive disease in chickpea growing areas. North Khorasan province is talented to chickpea cultivation and has a high level of to this disease. In the present study, disease responses of nine chickpea genotypes were evaluated under greenhouse and field conditions, for their response to a local A. rabiei isolate. In greenhouse experiment, the genotypes were sown in randomized complete block design with five replications. Three weeks old seedlings were inoculated with the fungus spore suspension and were maintained at 200e and >90% relative humidity for two weeks. In field experiment, genotypes were sown in split-plot design with three replications, so that the main plots and subplots were included inoculation treatment and cultivars, respectively. In spite of no resistant genotypes in field or greenhouse evaluations, Karaj 12-30-61 , Ghazvin, 12- 60-11 and 12-071-10105 showed tolerance in greenhouse and field. But Kaka was tolerant in field and susceptible in greenhouse. In Ghazvin cultivar, low yield is apparently due to reduction of pods number per plant. Among nine genotypes, Ghazvin and Karaj 12-30-61 were the most tolerant genotypes to blight. Both Jam and Kourosh were very susceptible but disease progressed until podding stage in Jam.

In this study, the effect of allelic variation for HMW glutenin subunits on qualitative characteristics of 145 genotypes including breeding lines, cultivars and landrace varieties of bread wheat (Triticum aestivum L.) were evaluated. Polyacrilamid gel electrophoresis in the presence of SDS was used to determine glutenin subunits patterns. Bread-making quality of the genotypes was tested indirectly by SDS and Zeleny sedimentation test, protein percent, hardness index, test weight, bread volume, grain moisture and percent of water absorption the analysis of variance revealed measured significant differences among glutenin subunits for prot4ein percent, water absorption, hardness index, bread volume and test weight. Subunits 1 and 2* at Glu-Al,7+8 and 17+18 at Glu-Bl and 5+10 at Glu-D1 lici, had the highest positive effects on bread-making characteristics. The results were also confimd by using canonical correlation analysis between HMW glutenin subunits and qualitative traits, especially bread volume, SDS and Zeleny sedimentation, volumes. The best genotypes for bread-making quality traits were those having a combination of (Null, 14+15, 2+ 12) and (2*, 17+18, 5+10) subunits. The correlation analysis indicates positive and significant relationship between 2* and 5+10 subuni8ts with hardness index, 13+16, 6+8 and 7+8 subunits with grain moisture percent, and the subunits of 7+8 and 7+9 with test weight.

A bio-economic model for calculating sire net present values (NPVs) was provided, by accounting for economic coefficients and transmitting abilities for milk yield and milk fat percentage. For this purpose data were used on costs and returns of a dairy herd with 1200 cows, and also on results of genetic evaluation of a random sample of sires which have been used for artificial insemination. The sensitivity of NPVs to price change of concentrate, forage, milk and milk fat were investigated. By doubling these prices, the mean NPVs were increased by 0.99%, 0.64%, 96% and 8.1% respectively. The change of prices resulted in change of correlation coefficients of new NPVs and base NPVs. The highest and the lowest correlations were related to feed price change, by 99.99%, and to milk price change, by 99.93%, respectively. The effect of feed price on the NPVs was not significant (p>0.05) and of milk and milk fat prices were highly significant (p<0.001). Because of sensetivity of NPV to factors of production system, it is not possible to rank the sires for a specific situation and then generalize them to others. There was less than 100% correlation between NPVs and milk and milk fat transmitting abilities, thus they can not been used as an alternative to NPVs in sire selection.

Competitive response of a winter wheat cultivar (Cn-5) to various plant densities of wild oat and levels of nitrogen fertilizer was investigated at the field Research Station of Ferdowsi University of Mashhad, College of Agriculture, in 1999-2000. A split plot experiment based on a randomized complete block design with 4 replications was used. Four levels of nitrogen fertilizer (25, 50, 75 and 100kg/ha) were assigned to the main plots and wild oat plant densities (0, 30, 50 and 80 plant/m2) to the subplots. The results showed that, wheat shoot dry weight and grain yield, the number of tillers and spikes per unit area and wheat 1000 grain weight were declined as wild oat plant density increased. Both crop and weed shoot dry weight and number of tillers per unit area increased, but the proportion of crop from total shoot dry weight and number of tillers per unit area decreased, as nitrogen fertilizer increased. Loss of wheat grain yield with increasing weed density was greater in high than in low nitrogen levels. Regression models were used to describe the effect of wild oat plant density on wheat grain yield. Wheat yield was described well by a linear regression model, using both absolute plant density and relative biomass of wild oat or a nonlinear regression model, using the relative density of wild oat in the weed-crop stand.

In spite of highly economic importance of white mushroom (Agaricus bisporus) and its world wide production, the breeding difficulties for yield improvement of this edible mushroom which is due to its biology is still under consideration. In this research the ways of improvement of the mushroom for yield by employing hetrosis phenomenon of interbreeding crosses was investigated. Spore prints of six commercials exotic and two cultivated domestic strains were prepared and after 15 to 25 days, 100 different spawn produced. In the above stages basidiospore variation in terms of growth rate and type of colony on PDA medium and wheat spawn was carefully investigated. Fruiting test was conducted to isolate homokaryons from hetrokaryons. One hundred Isolates were classified into four groups of high, medium, low and zero in terms of yield. The relationship of these yield classes with the type of colony was studied. Those isolates with zero yields were used in interbreeding crosses to produce hybrids. Some hybrids performed significantly better both in PDA culture medium and in the wheat spawn. RAPD markers used to briefly investigation of variation between some isolates of A15, showed high and positive correlation between number of bands and yield for each isolate. Key words: Agarics bisporus, Hybridization, Spawn, Fruiting test, RAPD.

Tomato Paste is one of the most important tomato products. Some of its characteristic is very important. In this research effects of heating on whole tomato and acid-hot break have been studied for improving the consistency and other characteristic of tomato paste. The results show that simple effects of these treatments improved the consistency and flavor of tomato paste. Due to increasing heating time in whole heating procedure and oxidation in low pH the paste color quality was decreased. By using the suitable variety and sorting this variation could be controlled. The interaction effect of treatments especially in the pH low than 2.5 had a certain reduction on consistency of paste due to pectin hydrolyze.

In order to investigate fall-winter sowing possibility of chickpea and comparing it with spring sowing from viewpoint of growth, development and seed yield, two experiments carried out in 1995-96 and 1996-97at Northern Khorasan Rainfed Station (in Sisab). Three planting dates including 4 Dec., 3 Jan. and 3 Apr. and six Kabuli chickpea cultivars in each year were compared in a factorial experiment based on randomized complete block design. Based on combined analysis of variance for two years, there were not significant differences among plant height, number of branches and their length per plant, pods number per plant, seed numbers per pod and 100 seed weights, in planting date levels. Although seed yield in 4 Dec. (with 34.1 gm-2) and 3 Jan. (with 32.3 gm-2) increased compared to 3 Apr. (with 29.6 gm-2) but differences were not significant. Cultivars had significant difference in seed yield (p≤0.05) but interaction of cultivar x year and cultivar x planting date were not significant. The results revealed necessity of more studies on fall-winter sowing such as selecting of suitable cultivars tolerate cold in this area.

Starter cultures are one of the most important factors affecting yoghurt quality. The qualitative and quantitative assessment of yoghurt starter bacteria (Streptococcus thermophilus and Lactobacillus delbrukii subsp bulgaricus) is valuable because some countries have proposed standards of quality yoghurt which may include the requirement that a minimum number of viable yoghurt organisms must be present at the time of the sale. Also, the proportion of two yoghurt bacteria is believed to be important in determining the quality of yoghurt. In the current study, nine different types of general and differential media were compared for the growth and differentiation of yoghurt bacteria. It was noted that although many media have been proposed for enumeration of yoghurt bacteria, only few of them proved to be reliable. M17 and acidified MRS (AMRS) performed as expected, but if using one medium is preferred, Tryptone Protease Peptone Yeast Extract agar (TPPY) and Reinforced Clostridial Prussian Blue agar (RCPB) are media of choice.

In order to investigaten the physiological and morphological traits associated with 50 years winter wheat improvement in Iran, an experiment was conducted during 1998-1999 growing season in Mashhad, Iran. Six winter wheat cultivars that had been released during the past 50 years, were planted on a randomized complete block design. Each cultivar was planted under its own optimum planting density and nitrogen requirement. The results showed that the annual average increases in grain yield, total biomass yield and harvest index were 83 and 86 Kg/ha and 0.0037% respectively. Dry matter accumulation, radiation use efficiency and leaf area index after pollination, nitrogen use efficiency and nitrogen uptake efficiency were higher in recent introduced cultivars compare to old cultivars. New wheat cultivars also had lower nitrogen harvest index to harvest index ratio and higher extinction coefficient than older cultivars. However older cultivars were taller and had longer internodes. Higher grain yield were positively correlated with higher number of fertile tiller and higher number of grain perm2.

Existing restrictions in spring sowing of chickpea (Cicer arietinum L.) as dry farming have made the study of Entezary sowing unavoidable. However, lack of suitable varieties of chickpea has endangered this system of sowing. This study was conducted at the Experimental station of Faculty of Agriculture, Ferdowsi University of Mashhad for two years (1997-99) to evaluate the reactions of 315 of Kabuli Chickpea germplasm to Entezary sowing. Ten seeds of each accession with a distance of 10cm were planted in rows with 50 cm apart without replication. Two planting dates were chosen in the late November and late December in 1997-8 and 1998-9 growing seasons. To determine the percentage of survival, seedlings were counted after winter. At the first sowing date of 1997-98,45.5% and in the second sowing date 51.8% of accessions were highly tolerant (rank 1) and / or tolerant (rank 2). In contrast in 1998-99 at first sowing 54.8% and second sowing 60.0% of accessions were high tolerant (rank 1) and / or tolerant (rank 2). Cold severity and duration in the first year were higher than those in the second. Therefore, a large number of accessions were killed. At first sowing date in both years, 84 accessions and second sowing date 110 accessions ranked 1 and / or 2.25 and 20 accessions (at date 1 and 2, respectively) selected on basis of survival index, yield per plant, weight of 100 seeds and tolerance to Ascochyta blight at each planting dates. one of selected accessions was in all dates in common. Results show that among the studied accessions there are some adaptive accessions to the Entezary sowing and obtaining such suitable varieties of chickpea is possible.

Soil erosion plays an important role in decreasing soil quality and agricultural products. Soil conservation is the preventive alternative that may have a role in decreasing soil erosion costs. Farmers have used vertical plow on the basis of experience and local knowledge and the effects of vertical plow on crop yield and quality of soil are tangible for them. this paper tried to examine soil conservation management in a bioeconomic modeling framework with an emphasis in local knowledge of farmers. It is shown that (I) soil erosion is a phenomenon present at any conservation management and impossible to completely avoid. Hence, some costs will be incured, (2) any kind of conservation practices that result in decreasing soil erosion and soil fertility mining may be effective in decreasing erosion costs. For example, vertical plow based on farmers knowledge has reduced in costs of soil erosion at least half as much as much as of its alternative, horizontal plow, (3) a considerable increase in farmer’s income is made because of traditional conservation every year, (4) Farmers are aware of the important of soil conservation and its benefits as result of their local knowledge. They would use conservation plow if they had suitable plowing machines for the steep lands and (5) The delay in using soil conservation practices by some farmers in due to increasing loss of yields and consequently, costs of erosion in soil with less than 10 centimeter depth being unimportant in terms of acreage and will get that depth in the long run with the present rates of erosion. The results justifies policy making, planning, credit support and application of advanced soil conservation measures or at least extension of traditional conservation practices, research about advanced conservation methods and allocation of sufficient budget for the application of the soil conservation practices.

Findings of a partial equilibrium analysis applied on time-series data of 1340-79 were used to forecast possible welfare effects of tobacoo market liberalization in Iran. Using a forecasting model, the effects were predicted for future. The results show that as a results of market liberalization, government expenditure and imports will decline. This policy increases the social welfare and creates social benefits as well. Despite a relative decrease in consumers welfare, the improvement in producer’s surplus is so high that can lead to an increase in social welfare. In general, tobacoo market is recommended to be liberalized in next coming years.