IRANIAN JOURNAL OF AGRICULTURAL SCIENCES (JOURNAL OF AGRICULTURE)
Year:2007 | Volume:38 | Issue:3|Papers Count:24

Effect of substitution of NaCl by KCl on the lipolysis of UF white cheese during aging (storage time) was studied. Four treatments of different mixtures of UF white cheese with the ratios of NaCl/KCl: 1.50%NaCV1.50%KCl, A; 1.00%NaCl/2.00%KCl, B; 0.75% NaCV2.25%KCl, C; and D as control with 3.00% NaCl were treated by dry salting to produce low salt cheese. Lipolysis was analyzed by measuring acid degree value and through gas chromatography. The results of acid degree value (ADY) showed that all treatments after 15, 30, 40 and 50 days of aging, except after one day aging, had significant (P<0.05) differences. However treatments D and A had the lowest levels of ADV, Moreover, the results of GC showed that the profile of free fatty acid (FFA) except C18:0in all treatments and after the same aging periods of 10, 25, 40, 55 and 70 had no significant differences. It has to be noted that there were no significant differences observed among volatile FFA, in all treatments and after the same aging time period.

Olive leaf spot or peacock spot caused by the fungal pathogen Spilocaea oleaginea, can cause reduced growth and yield, bringing in economical loss to olive trees and orchards. A survey of olive leaf spot and an evaluation of resistance of 25 cultivars to this disease were carried out during 2003 to 2005 in Mazandaran province. According to the obtained results the degree of infection and severity of olive leaf spot was low in areas that were to a larger extent exposed to wind and dry conditions (hills and rivers banks), while it was very high in areas where leaves of olive trees were exposed to calm weather with high rainfall and humid conditions (north side of hills). Any investigations of different ages of olive trees showed that there was a positive correlation between disease severity and increased age. Most 2-3 year young trees were resistant to very resistant and a majority of 10-12 years trees were susceptibleto very susceptible. An evaluation of olive cultivars' resistance showd that Manzanilla, Roughani (Roudbar), Zard, Kalamon, Sevillano, Mission, Amygdaloidal, Karolea, Konservolia, Koroneiki, Frangivento, Roughani (mohaly Gargan), Ascolana, Coratina, and Velanonia were susceptible, while Arbequina, Nabali Balady and Moraiolo semi susceptible, and Mary, Frantoio, Rosso, Simarimella, Picual, Leccino, and Dolce Agogia being resistant. With a consideration of the disease severity in different parts of the region, it is proposed that seven resistant cultivars (Mary, Frantoio, Rosso, Simarimella, Picual, Leccino and Dolce Agogia) to peacock spot disease be used for cultivation.

The purpose of this research is a technical and economic evaluation of subsurface drainage system implementation in date palm orchards of Abadan with four cases of drain envelopes including local gravel, standard gravel, and synthetic envelopes (polypropylene 700 and polypropylene 450). To achieve this, 16 laterals (subsurface drains) were installed in a 12 hectare area of date palm, in irrigation and drainage project of Abadan, in 2004. Four laterals equipped with envelopes were constructed. In order to determine and evaluate hydraulic resistance, water table curves and other needed parameters, pizometers were installed on and between drains at 0.25L, 0.5L and 0.75L (L is the length of lateral) and started to record parameters for the assessment of: 1- Technical and economic evaluation for application of various envelopes in subsurface drainage system, 2-Economic evaluation of the project and finally a selection of the best or other acceptable methods for the construction of subsurface drainage system in date palm orchards of Abadan.Finally, with regard to the obtained results, and according to importance, the fallowing four acceptable methods are proposed: 1) Construction of subsurface drainage system using trencher and pre-wrapped pipes with synthetic envelope pp-450 (Iran- made). 2) Construction of subsurface drainage system using trencher and pre-wrapped pipes with synthetic envelope pp-450 (made in Netherlands). 3) Construction of subsurface drainage system using trencher and pipes (made in Iran) with standard gravel envelope. 4) Construction of subsurface drainage system using backhoe and pipes (Iran made) with standard gravel envelope.

Cyclamens are some of the most important ornamental plants flowers of which appear in winter. It's a native of Iran where its different genotypes can be found. Unfortunately, there is no comprehensive information available on these genotypes presently. In order to study the quantitative and qualitative traits, a trial was done on 26 genotypes, in which 23 traits were investigated. The results showed that traits were significant and also it was shown that positive and negative significant correlations existed among some important traits. Factor analysis showed that a majority of traits related to the color of flowers, petiole and young leaves ad axial site, and also flower shelf life are the components of the main factors. Effective traits categorize in 6 groups that cover a total of 86.89 percent of total variance. Cluster analysis, using these 6 factors, put the genotypes into 5 clusters at a distance of 0.1 similarities. Genotypes in clusters were most different in color of flowers, flower shelf life and also in petiole color and young leaves ad axial site.

Tomato (Lycopercicon esculentum) is one of the most important vegetable crops, the fruit of which are widely consumed used by humans. High price of tomato as an out of season crop in Bushehr province has made it a motivation for farmers of this area to cultivate it during fall and winter. Search for drought resistant tomato cultivars has been so sensed especially following the recent drought in the south of Iran. Therefore, a study was conducted in Bushehr Agricultural Research Center greenhouse (located in Borazjan) to determine the effects of water stress on 10 tomato cultivars in the vegetative stage. The experiments were carried out through a completely randomized design (Factorial) with three replications during 2004. The treatments were as follows: Irrigation \vater depth in two levels (irrigation at 50 and 70 percent of water depletion) and 10 tomato culth'ar seeds (fallat CH- Petoearly CH - Thef -Fallat III - Perimoearly- Viova 110- Calj N3 - Early Urbana VF - Vana Fallat - FDT 202). Results indicated that tomato properties (stem and root length and dry matter- leaf dry matter- plant height - Root/Shoot ratio –relative growth rate- leaf area ratio- water use efficiency) were significantly affected by either one of the both factors as well as by their interactions at 1% level, except only for the interactions of R/S and RGR which were not significant. Among the tomato cultivars, Fallatll1and FDT202 exhibited better responses to water stress. A total of 14750 and 13550 milliliters of water were applied in the two irrigation treatments and in a number of 32 and 25 times.

Acrolein was evaluated as a potential fumigant to control three stored product insects. Different doses of acrolein were introduced into glass jars, containing adults of Callosobl7lchus chinensis (1.), Tribolium castanewn (Herbst) and Rhyzopertha dominica (p.). In each jar, the insects were kept at the bottom of the fumigation chamber. Mortality rate was recorded 24 hours after initiation of exposure. LC50and LC95 values estimated were 6.05729 and 8.36819 m1/ 1 for C. chinensis. The secriteria were 10.29 & 20.42379 m1/1 for T.castaneum and 6.99 & 12.30 m1/1 for R. dominica, respectively. To determine the lethal dose of acrolein on immature developmental stages of R. dominica, equal quantities of wheat were placed in similar glass jars, with different amounts of acrolein applied onto them. Newly emerged adults were recorded weekly for 11 consecutive weeks. It was revealed that no adult insect emerged during this period of time due to introduction of 70 m1/1 of acrolein.

This experiment was conducted to evaluate the effect of whole soybean heat processing time in different inclusion levels on male broilers performance in comparison with a ration based on the equivalent value of soybean meal and soybean oil. Four hundred and thirty two male broilers at 21 days of age were randomly taken in 9 treatments, each of which had 4 replications of 12 chickens.A factorial experiment on the basis of a complete randomized design was used in this study. Broilers were fed by 4 types of soybean seeds, which were respectively processed for 0, 20, 40, and 60-minutes, and in 2 inclusion levels (20 and 47 percent). They were compared with the control groups, ration based on the equivalent value of soybean meal and oil. Heat processing was accomplished using common lab ovens at 150°c and for specified times. The results indicated that heat processing has a significant effect on broilers' body weight, feed consumption as well as feed conversion ratio at 42 days of age (P<0.05). Also, observations indicated that 20 percent inclusion level resulted better as compared with the control group and in contrast to the 47 percent inclusion level. Raw soybean seed consumption resulted in a significant increase in pancreas size of the chicks as compared to processed, and the control groups (P<0.05). In contrast, abdominal fat percentage for chickens fed by experimental rations showed no significant difference (P>0.05). In total, the best performance results were achieved by the use of rations containing 20 percent of 60 minute processed soybean seeds; these results being identical with those of the control groups.

Various species of the genus Artemisia are used for their Pharmacological, antimicrobial and antioxidant activities. Two species of this genus, namely Artemisia scoparia and A. aucheri are widely distributed in desert areas of Iran especially in south Khorasan province. In order to study the chemical composition of these species, their aerial parts were collected from Bajestan (Khorasan province) at flowering stage. The essential oils were extracted through hydro-distillation of air-dried samples, and their chemical composition was determined through GC-MS. Oxygenated monoterpens were the major components of oils in both species. a-thujone (81.7%), b- thujone (14.5%) and 1,8- cineol (1.9%) were the major compounds in the essential oil of A. scoparia. The essential oil of A. aucheri was rich in linalool (44.1%), gernyl acetate (10.7%), (E)-citral (9.7 %) and (Z)-citral (7.7 %). Studying antifungal activity of either of the essential oils against four soilborne phytopathogenic fungi showed that the essential oil of A. aucheri is of more inhibitory effect than that in A. scoparia. The minimum inhibitory concentrations (MlCs) of the essential oil of A. aucheri against Rhizoctonia so/ani, Tiarosporella phaseolina, Phytophthora citrophthora and Pythium sp. were 150, 300, 1200 and 300 mL/L respectively. Minimum EC50 (51.03 m/L), resulted from A. aucheri oil inhibitory effect on R. solani.

Saliferous - gypsiferous soils are among a vast extension of soils in arid and semiarid regions of the world. Although there have been numerous studies dealing with these soils, yet many scientists are still interested in the genesis and particularly morphology of gypsmn as well as more soluble salts in these soils. This study was carried out in Barn region to investigate the soil genesis as well as morphology of gypsmn and salts in soils of this area. Eight pedons located on a gravelly alluvial fan were field described and sampled. Physicochemical determinations, including; soil texture, electrical conductivity of saturated extract, soil reaction, organic carbon content, gypsum percentage, and soluble anions & cations were determinated in samples, based upon standard methods. Undisturbed oriented san1pleswere taken for thin section preparation. SEM assisted EDS was employed for more detailed morphological study of these salts. The soils were classified as Petogypsic Haplosalids. Pedogenic gypsmn shows a range of habits in these soils, ranging from fibreous to granular and lenticular in the petrogypsic horizon, to tabular pseudo-hexagonal habit on gypsum, pendant at depth. Cubic halite crystals have been observed under the petrographic microscope, probably because of having been trapped between less soluble gypsmn crystals. The distribution pattern of gypsmn and salts suggest that the gypsmn crystal pendants of the lower depths have been formed under a more hmnid climate than that of present days, whereas, gypsmn and salts on the upper petrogypsic horizon are more related to the presently drier climate.

Drawbar power produced by tractor has gained and is gaining ever increasing importance. Tractive efficiency is a measure of traction performance of the tractor and is widely used for evaluating tractor operation in the field. This study was conducted to develop a general equation for estimating the tractive efficiency of a tractor by using dimensional analysis technique. Therefore a single moldboard plow mounted on a U-445 tractor was put into operation for the test on a loamyclay soil. Drawbar force, rolling resistance force of the drive wheels, slippage of the drive wheel, cone index of soil, theoretical and actual velocity and dynamic load on driving wheels were either measured or calculated. The experiment was performed at four plowing depths (10, 15, 20 and 25 cm) in three replications. Finally the general equation for an estimation of tractive efficiency was obtained as:T.E. =(10)2.830[(P/W)(0496) x (CI.b.d/W)(-0.280) x (10)(-0.720)(S)(10)(-4.41)(r/d)´x (10)(9.965)(T.F/W)] 1.0076 This equation can be employed to estimate tractate efficiency of various combinations of tractors and moldboard plows provided the dimensionless terms fall within the limits experienced in this research. By use of this equation and through employing the initial data for tractor and soil, the tractive efficiency could well be predicted.

To investigate the effect of different sugars (sucrose, glucose and fructose) on haploid induction of nine Iranian onion landraces via in vitro whole flower culture, this research was carried out, while traits such as embryogenesis, plant regeneration, plant survival, vitrified flowers and time required for embryo observation were evaluated. From a total of 4758 cultured flowers in different media, 64 embryos (1.34%) were produced. The highest and lowest embryo percentages were obtained in mediums containing glucose and fructose, respectively. Eghlid- e- Fars and "Tarom- e- Zanjan" landraces exhibited the highest and lowest response to in virto gynogenesis (2.32 and 02%, respectively). The highest embryogenesis (5.06%) belonged to "Sefid- e- Naishabur" in medium containing glucose and Eghlid- e- Fars in medium containing sucrose (4.51%). The highest and lowest plant regeneration belonged to "Eghlid- e- Fars" and "Tarom- e- Zanjan", respectively (2.19 and 0.19%). "Eghlid- e- Fars" had the highest plant survival rate (63.89%), while "Sefid- e- Qom" the lowest (13.89%). Therefore, glucose as well as sucrose could be used as carbohydrate source, while use of fructose is observed to reduce embryogenesis.

Fruit set in pear is affected by several genetic and environmental factors one of which is incompatibility. Self-incompatibility (SI) in the Rosaceae is controlled by a homomorphic, gametophytic, monofactorial, multiallelic incompatibility system, where pollen rejection occurs in the style. The incompatibility locus controls self-incompatibility as well as intra-specific cross incompatibility.In the present study PCR along with specific primer was applied to investigate SI genes. This method is easy and fast and not affected by pollination factors. DNA from five European pears (Shah-Miveh, Spadona, Sardrood, Mohammad-Aliand Bartlet) was extracted using CTAB method. Specific primers amplified SI gene. The results showed that primers could amplify SI gene. S-locus was existent in the mentioned cultivars. The first pair of primers showed that there was one pair of SI, S3-S7, alleles in Shah-Mivehand in Mohammad-Ali. Sardrood and Bartlet had similar band patterns and had had S2 allele. In Spadona, Sardrood and Bartlet a 1400 base pair band was amplified which may be a new allele. The other primers resulted the same. Therefore, in order to obtain suitable yield one should pay attention to this fact and employ cultivars with different alleles in establishment of new pear orchards as well as in breeding programs.

The effects of dietary supplementation of a probiotic on daily feed intake, egg production, egg weight, feed conversion ratio, plasma and yolk cholesterol, as well as immune response in laying hens were investigated. In a completely randomized design, seventy-five 26-week-old layers were randomly assigned to 5 treatments with 5 replicates each. A diet based on corn-soybean meal was used. Treatments consisted of 5 experimental groups including: T (1): control group that received the basal diet, T (2): basal diet+400gr/ton probiotic every other day. T (3): basal diet+400gr/ton probiotic every weeks T(4): basal diet +400gr/ton probiotic every other two week. T(5): basal diet+ 400gr/ton probiotic every three weeks. There were not any significant differences observed among T (2), T (3) and T (4) regarding egg yield, egg weight, cholesterol of plasma and yolk (P<0.05). T (2) and T(3) had maximum influence on the immune response(p<0.05). The results indicated that continuous and periodic (every other week and every two weeks) consumption by layer of probiotic have respectively the most positive effects on layers' performance (P<0.05). Periodic layer consumption of probiotic has the highest effect on decrease in yolk cholesterol (p<0.05).

This study was conducted to examine a new method for determining feedstuff dry matter degradation kinetics. For this purpose, an assembly of a one-liter volumetric flask, pH meter, gas output valve, buffer solution buffer and shaker in a water bath was employed. For each trial, 800ml of unfiltered rumen fluid was collected. Comparisons were made between the new method, in situ and in vitro data. In nylon bag technique, feed samples consisting of alfalfa, wheat straw and a mixture of both in different ratios were incubated for 0, 24, 48 and 72h in the rumen of four cannulated varamini rams as well as in the artificial rumen. Dry matter degradability parameters were estimated through Naway program. The new method's results were compared with in situ and in vitro results. in situ-in vitro results were different from in situ and there were significant differences between in vitro results (P<0.05). But in situ-in vitro feedstuff degradation means were close to in situ, rather than in vitro results (r2=0.94vs. r2=0.91).The newly proposed procedure can be recommended for estimating feedstuff dry matter degradation kinetics.

For promotion of pistachio export, investigation concerning mechanized harvesting to improve hygiene in harvest is necessary. In this relation, for harvesting pistachio by tree trunk shaker, initially and in another research work, an experimental trunk shaker had been designed and developed by the same author, which was then optimized and tested in this research. The initial experimental trunk shaker suffered from some shortcomings some of which could be mentioned as: 1- Clamping to the trunk being tedious. 2- Shaker handling 3-Time consuming process of attaching and detaching of the shaker to the tree trunk, free to move shaker arm and adjustment of shaker arm being stepwise as against being continuous 4- And finally non-gentle shaking of the tree. Those shortcomings were observed, taken into account and then overcome in the process of optimization to a pistachio harvester machine, which was put to test in Rafsanjan. Evaluation of the machine was carried out through a completely randomized design with 40 trees and at a 40 mm stroke and 20 HZ frequencies. A comparison of results between the two apparatuses revealed that the difference in percentage of shedding as well as in time taken for attaching and detaching of the shakers from the tree was significant (p<0.01). This experiment revealed that the tree trunk shaker pistachio harvester with a 77.9% of shedding and time requirement (for attaching to and detaching from the tree) of 15.5 seconds as compared to 30 sec for the former was better fit for pistachio harvesting. This indicated that many of the previous problems and shortcomings had been overcome due to increase in weight, and an addition of attaching clamp, transport wheels and damper to the harvester.

In this study the effect of packaging material type on moisture variations and quality character of Orthodox tea during storage period were investigated. Black tea was packed in seven types of packaging materials and then kept in two different stores, in Guilan and the other in Tehran for three years. Quality tests consisted of, moisture content, caffeine, the aflavin and thearubigin, measured every three months. The data was analyzed using Mstatc. Increase in moisture content in Guilan store was different from that in Tehran store, which affected quality parameters especially in Guilan sample. Among seven type of packaging materials, two layer lining cardboard and shell covered cardboard were found more suitable for prevention of moisture penetration and maintenance of quality characters.

Gholam-gardeshy furrow irrigation is a modified form of furrow irrigation, mainly used in Iran. However, to date no research has been noted about the hydraulic performance of this method of irrigation. The use of this method of irrigation, especially in heavy soils and steep slopes, can reduce tail water runoff as well as increase application efficiency as compared to the furrow irrigation. To evaluate the performance of this method of irrigation and to compare the results with a furrow irrigation, in three experimental fields, (Khazaneh with sandy clay loam soil texture and 0.3%, I% and 2% soil slopes, University with sandy clay loam soil texture and 0.29"10soil slope and finally Roodasht with clay soil texture and 0.1% soil slope), ordinary and Gholam-gardeshy design of were designed and equipments including constant head water delivery system to the furrows were installed in any of the experimental fields. To determine the parameters of Kostiakov-Lewis infiltration equation, volume balance method was employed. The results showed that for the same irrigation time and inflow discharge the velocity of advance and tail water runoff was less for Gholam-gardeshy furrow irrigation as compared to the furrow irrigation. In the three experimental fields, for Gholam-gardeshy furrow irrigation, infiltration was more as compared with the furrow irrigation and as the slope of the field increases the differences between the two methods decrease. Both methods had nearly the same furrow cross section in the three experimental fields. In the three experimental fields, as the net depth of irrigation increased the application efficiency increased for either method. In both irrigation methods the determined advance equations were able to predict the measured data with a coefficient of determination of more than 90 percent. The difference between the two methods for longitudinal advance and infiltrated water along the field was significant at 5 percent level.

In order to investigate the effect of several seed tubes on the scattering of seeds, when drilling seeds, experiments were done while using a John Deere model seed drill equipped with three point hitch and two lateral drive wheels. In this research a fixed test area (greasy nylon surface) along with a mobile seed drill were employed in place of an experimental test rig (grease belt). A 3x4 factorial experiment with a completely-randomized design was employed for experimentations and evaluations. The first factor was comprised of seed tube types at four levels (2 piece telescopic, 3 pieces telescopic, screw seed tube, and flexible ribbon seed tube). The second factor was forward speed at three levels (5, 7, 9 Km/h). The effects of these variables were evaluated on longitudinal as well as lateral scattering of seeds. The analysis of data indicated no significant effect on longitudinal seed scattering in any of the treatments. Continuous flow of seeds from the seed metering device is the main explanation for this behavior, which compensates for the bouncing reactions of inner side of seed tube walls. However at forward speed of 5 Km/h, the 2-piece telescopic seed tube showed better results as compared to others. The effect of forward speed on lateral scattering was significant at 99 percent probability. The shape and structure of the flexible ribbon seed tube accounted for the low lateral scattering values. In total, a flexible ribbon seed tube and forward speed of 7 Km/h (on level surfaces) resulted the best, and is recommended in seed drilling.

UV-C irradiation was used to increase storage shelf life of Red Delicious and Golden Delicious apple cultivars. A factorial design of three different irradiation times and with 4 replications was employed for treatment of the fruits. The treated fruits were stored in a cold storage of 1±1°C with 85-95% relative humidity for 6 months. Samples from cold stored apple fruits were then taken and stored for 7 days in 25°C after which quality factors, including pH, titratable acidity, total soluble solids, total soluble solids to acidity ratio, and fruit firmness, were measured. Results indicated that after a lapse of 6 months, irradiated fruits for duration of 15min had a lower pH and TSS/TA ratio and higher TA and firmness than the 5 min irradiated, and control fruits. A significant difference was observed for total soluble solids in irradiated Red Delicious fruits for 15 min The ones irradiated for 5 min. and control at the end of storage period. Red Delicious apples (after 6 months) had a lower TSS and TSS/TA ratio and while a higher firmness than Golden Delicious apples.

This experiment was conducted to study the effect of dried pistachio by-product on the diet of fattening lambs. Thirty-two male lambs, with initial weight of 25.9±1.9 kg, were used in a completely randomized designed for a period of 3-month experiment. Four diets containing 0, 10, 20 and 30 percent pistachio by- product, each treatment with 2.5 Mcal ME and 135 gr/kgCP, were fed to the lambs ad labium. Result indicated that, average of final lambs live weight for the diets contained 0, 10, 20 and 30 percent of pistachio by-product were respectively 44.5, 40.4, 39.5 and 34.8 kg at the end of the experiment. Mean daily weight gain was 216.3, 177.0, 167.9 and 123.7 gr/day respectively and average feed intake was 1470.4, 1320.1, 1201.5 and 1004.4 gr/day respectively. Feed conversion ratio was respectively 7, 7.5, 8.3 and 11.6 for the above diets. Diet containing 20 percent of pistachio by-product did not effect on the daily weight gain, live weight and feed conversion ratio of the lambs (P>0.05) and diet containing 30 percent of pistachio byproduct significantly (P<0.05) reduced feed intake, daily weight gain, final live weight and increased feed conversion ratio. It can be concluded that pistachio by-product may be used up to 20 percent in the fattening lamb diets.