IRANIAN JOURNAL OF AGRICULTURAL SCIENCES (JOURNAL OF AGRICULTURE)
Year:2007 | Volume:38 | Issue:1|Papers Count:28

Fuzzy logic was applied as a decision support system to grade Golden Delicious apples. Such features as color and size are measured through a data acquisition system consisting of an apple sorter, illumination chamber, webcam and a PC. In total 250 apples were selected for the test. The selected apples were graded by human experts based on their color and size. Five different sets or grades ranging from very low quality, to very high were produced. In order to find the performance of proposed fuzzy inference system (FIS) the same sets of fruits were fed to the Fuzzy expert system. For input (color and size) and output (apple grade) fuzzy linguistic variables of the FIS, triangular and trapezoidal membership functions were selected. Totally, 125 rules with logical AND operator, Mamdani implication, and Center of maximum method for defuzzification were employed to develop an efficient fuzzy expert system for decision making concerning apples grades. The algorithm is implemented in Visual Basic 6 programming language in 1825 lines of program. The developed VB program can automatically capture image of each apple and extract its RGB color and size features. The software generates all the 125 rules by comparing these features with the reference input. The rules are then exported to Matlab for further investigation concerning the precision of algorithm. These tests were conducted on a two way system i.e. off-line and on-line. Grading results obtained from the developed FIS scheme shows 91.2%, and 95.2% agreement for off-line and on-line methods, respectively, as compared with the results obtainted through human expert. These show the good correlation between the results obtained from the FIS and human expert tests. Therefore, based on these results the automatic apple sorter can be designed and developed.

In order to study the effect of AM fungi and phosphorus on P uptake by tea seedlings, a study soil sample was selected from Tea Research Station of Rezvanshahr, Guilan Province. The soil was sterilized in an autoclave at 1.2 atm for 1 hour. The experimental design was a factorial complete randomized blocks one with two factors of mycorrhizal fungi (non-mycorrhizal application, as control, Glomus etunicatum, Glomus intraradices and Glomus versiforme) and phosphorus (0, 8, 35 mg/kg soil) with three replications. Colon 100 Iran was used for tea cultivation. Before tea seedlings planting, inoculums were added to the soil. Pots moisture content was kept at 60% F.C. At the end of 16th week of growth, plants were harvested and prepared for chemical and biological analysis. Data analyzed with MSTATC & Excel softwares. Results of analyisd of variance showed that simple effect of phosphorus and mycorrhizal fungi on plant phosphorus content was not significant, wherea their interaction effect was of significance (p<0.01), so that those inoculated with G. versiforme in P0, had a maximum content of phosphorus. Consequently, it can be recommended that for soils similar to the study types of soil, G. versiforme would be more efficient in enhancing phosphorus uptake than either G. etunicatum or G. intraradices, respectively.

Soybean seed is one of the important sources of oil and protein supply. Economical productions of soybean seed mean sound seed accompanied by maximum rate of germination. Soybean seed cracks in shell during harvesting, cleaning, transport and during drying processes, causes decrease in germination rates. Limited information is availble to show the relationship between germination rate and drying temperature as well as drying depth. The objective of this research is to investigate the effect of drying air temperatures of 25, 30, 35 and 40oC as well as drying bed depths of 5 and 10 cm on cracking percentage in Sahar and Hill varieties. A factorial statistical design based on randomized complete blocks was used in this research work. The results showed that with an increase in drying air temperature from 25 to 40oC, the percentage of cracks increase from 12.95 to 43.80. With an increase of bed depth from 5 to 10 cm, crack percentage decreased from 27.9 to 24.3. Sahar variety was more sensitive than Hill with respect to cracks in shell. An inverse relationship was observed between the percentage of shell cracks and the rte of germination of soybean seeds with a coefficient of determination of 0.95. It can be concluded and recommended that a depth of 10 cm is more appropriate than 5 cm for drying of Hill and Sahar soybean varieties. The drying air temperatures of 30 and 35oC were the most suitable for Sahar and Hill varieties, respectively.

In this study the effects of grain moisture content, variety and whitening time on whiteness index, as well as the percentage of breakage were examined. The varieties used were Alikazmi, Binam and Khazar with three moisture content levels of 12.5-14%, 11-12.5% and 9.5-11% on a wet basis. Whitening times were 15, 30, 45 and 60 seconds. The results showed that the whitening times had no significant effect on breakage percentage, but increase in whitening time from 15 to 60 sec. caused an increase in whiteness index. There were significant differences observed among the varieties. Aliazemi and Khazar sustained a maximum and minimum rice breakage, respectively. Whiteness index of Khazar variety was significantly higher than that in the other two varieties. Rice breakage was a minimum in the range of 9.5-11% moisture content for all the three varieties.

The best recreational use of park and green spaces as well as the best calmness from the beauty of parks is achieved when a sense of safety avails in those spaces. Safety is not provided in parks and urban green spaces, due to improper design or a lack of performing the effective principles of management in which design is an important part. The problems in safety management, have forced us to think of ways to make some everlasting and important decisions. On the other hand, awareness of disasters and dangers in a pattern of smart systems is the key to improvement, and progress in safety. According to references, safety management systems are totally divided in two parts of classical and modern. In this study, the opinions of 450 urban people, users of green spaces, were assessed to find their expectations, and points of view for observing the principles of safety, as well as to investigate the kind of required safety management system. The results showed that users don't have a sense of safety at parks. Some practical ways and users suggestive methods are discussed. The problem in safety mostly arises because of having no safety program or united and regular performance of these safety measures along with other management programs.

In order to find the optimum effect of fertilizer ratio N, P, K on bulb quality and quantity characteristics of tulip cv: hybrid darwin Apledoorn, experiments were conducted in a randomized complete block design using different fertilizer treatments. In those experiments, 3-year tulip Apledoorn bulbs were planted in pots containing sandy loam soil. The following treatments were applied through hydroponics method: 1- Control, solution No.1 with N, P, K (6, 1.6 and 2.6 meq/l), 2- solution No.2 with N,P,K (6, 4.05 and 2.6 meq/l), 3- solution No.3 with N, P, K (6, 4.05, 4.6 meq/l), and 4- solution No.4 with N,P,K (6.25, 1.6 and 4.6 meq/l). At the end of vegetative growth and when the leaves were dried, bulb diameter, wet & dried weight, proteins content, N, P, and K content of bulbs were found out, and the data statistically analyzed. Results revealed that among performed treatments the nutritional solution No.3 with respective N, P, K of 6, 4.05, 4.6 meq/l) increased bulb size, proteins contents and bulblet number in tulip (p<1%).

The use of fertilizers in agriculture has been recognized as a potential source of environmental pollution especially in water and soil resources. An understanding of the factors influencing water and nutrient transport through soil profile is helpful for nutrient management, to minimize the adverse impacts on environment, and to trace nitrate leaching below root zone. In this study, water samples were collected from below the root zone and measurements were made through spectrophotometry to assess the nitrate transportation below the root zone. A field site experiment (under corn production) was conducted in the cropping period of year 2004. Two mathematical and hydrological models, LEACHN and DRAINMOD-N were used to simulate nitrate leaching. These models were calibrated by adjusting nitrification, denitrification rate constants to reach the best agreement between measured and predicted data. Results indicate that the nitrate concentration rates predicted by models were close to the measured nitrate concentrations. Also, in these two models, the moisture and its trend during the growth period was predicted by considerable accuracy. Correlations between measured and predicted data were significant at one percent level. Results and scenarios indicate that the two models can be used as reliable tools to manage environmental pollution in irrigated lands.

This study was conducted to determine ruminal degradation kinetics of DM, NDF and ADF and in vitro digestibility of some range species. Forage samples (Vicia villosa, Bromus tomentellus, Hordeum bolbusum, Festuca ovina, Agropyron tauri, Agropyron trichophorum, Prangus ferulacea, Ferula orientalis, Lathyrus L. and Taeniatherum L.) were collected at the pre-flowering stage on the same date by plotting from natural pastures of Kurdestan province of Iran. Four Varamini rams fitted with rumen fistula were used to determine in situ disappearance characteristics of forage samples.

First lactation test day records on 36487 cows, collected during years 1991-2002 in the Iranian Animal Breeding Center, were used in this research to investigate the trend of milk yield over lactation time, and to study the effect of factors determining the shape of lactation curve. Seven mathematical functions were fitted to individual records and based on the coefficient of determination, the incomplete gamma function was found to be the best to describe the lactation curves and therefore was selected as the most suitable function. Lactation curve traits that were employed in the analysis included a scaling factor associated with yield at the beginning, the inclining and declining slopes before and after peak yield, peak yield, DIM to reach peak yield, persistency and total milk yield, estimated from parameters of incomplete gamma function. Herd-year-season, DIM at the first and the final records, and days open had significant effects on the mentioned traits (P<0.01). The phenotypic correlation between total milk yield and all traits, except for the inclining slope, were positive. Total milk yield was highly correlated with peak yield (r=0.90).

Fourteen rc mutant and fourteen normal male birds (Rhode Island Red suie) were employed in a study to determine the effects of rc mutation on semen characteristics, testosterone profile and spermatogenic tissues. Similar birds were randomly selected at 12 weeks of age and placed in 2 separate pens. The birds received similar diet and 16L: 8D light program during the experiment. Semen was collected during weeks 16 – 18 from each bird twice a week and evaluated for semen volume (SV), sperm concentration (SC), total sperm count (TSC), percent sperm motility (%SM), dead sperm (%DS), and sperm metabolic activity (SMA). To determine the testosterone concentration (TC) in plasma, blood was collected on week 12, 16 and 18. Collected testicular tissue was processed and evaluated for somniferous tubule diameter (STD), round spermatid number (RSN), percent-elongated sperm (%ES) and semineferous tubules length (STL). Body weights (BW), comb weight (CW) and testes weight (TW) were determined at the end of experiment (week 20). The SV, TSC, and SM percent were significantly higher in normal birds where as DS percent was significantly higher in blind birds (P<0.05). The SC did not differ significantly between the two groups but the value was higher in normal birds. The sperm metabolic activity in the first hour of collection did not differ significantly between the two groups but after 24 hours; the level of SMA in normal group was significantly increased (P<0.05). The level of TC did not differ significantly between the two genotype groups but normal birds had higher TC in all collections, except for the last one. The STD, RSN, ES percent and STL in control birds were higher as compared to blind birds but the differences were insignificant except for ES percent. The BW, CW and TW between the two groups did not differ significantly but the weights were higher in the normal group than in blind birds. Statistical analysis of semen characteristics, testosterone profile and histological factors indicate detrimental effects of rc mutation in prepubertal blind male birds due to a lack in light receiving.

A study was performed to determine a more appropriate method of estimation of loamy soils relative saturated hydraulic conductivity through Guelph permeameter. The hydraulic conductivity measured through inverse hole method was compared to those obtained using different analyses of Guelph permeameter. Experiments were carried out in research farm of Abourayhan Campus, university of Tehran. Results showed that there was a significant difference (P<0.05) between means of inverse hole and Guelph permeameter analyses and similar results will be obtained if the means of Guelph analyses are multiplied by a constant coefficient of 3. Also there was not a significant difference (P<0.05) observed between means of two ponding height analysis and Richards' regression analysis. These analyses were as equivalent methods for loamy soils. Results of this study indicate that Richards' regression analysis could be recommended as a method for measuring loamy soils saturated hydraulic conductivity and would be a more appropriate method in application. Also, applying a suitable value of sportive number (a*), the single and two ponding height analyses would yield the same results.

Enhancing grain yield is one of the major objectives in many plant breeding programs. Since the economic return of a crop plant depends largely on its different trait values, plant breeders consider simultaneous selection for those several traits that maximize the economic value of a plant. Use of selection indices is one of the most effective means in obtaining this objective. In this study, 49 rice cultivars were provided through the Rice Research Institute of Iran (RRII) and evaluated using a simple lattice square design on the research farm of Tonekabon Agricultural Teaching Center (TATC) in 2001. Analysis of variance indicated that the genotypes exhibited significant difference for all the traits studied. Phenotypic and genotypic correlation coefficients between grain yield and fertile tiller number, total tiller number, and grain number per panicle were positive and significant. Correlation analyses using path analysis procedure indicated that the greatest effect on grain yield was due to the fertile tiller number. Moreover, grain number per panicle and 100 grain weight had significant direct effects on grain yield. As evaluation of selection indices using these traits (i.e. fertile tiller number, grain number per panicle and 100 grain weight) together with grain yield indicated that Asgari Tarom, Arjantin and Lebant were among the elite cultivars. However, replication of similar trials and evaluation of other cultivars are needed and recommended for more accurate and dependable results.

Ferula galbaniflua (Barijeh) is a natural plant of Iran the exudates of which, (galbanum gum) can be used in food industry. The gums was analyzed for its composition using HPLC, and by comparing the results with standards, the constitutional form of sugars and uronic acids in extracted sample were determinated. The effects of solvent type (methanol, ethanol, propanol and butanol), temperature (50, 70, 90 oC), and pH (4, 7, 9) on the extraction yield and on the purity, as well as on color of extracted gum were investigated. As to the effect of solvent type on extraction, maximum yield was obtained through methanol and ethanol extraction. Extraction yield was highest in acidic pH, and temperature increase led to a higher extraction yield. Increasing temperature and pH introduced more impurities into extracted gum. Neither temperature nor pH affected the color of gum. The analysis indicated the persence of galactose, arabinose and galactoronic acid from among which galactose consisted the major one.

For a decrease of agricultural crop losses, it is essential to estimate of paddy layers´ moisture content at the end of a drying process. In this study, intelligent method of artificial neural network was employed to predict paddy layers´ moisture content in a range of final moisture contents of 10 to 14% (w.b.). Drying experiments were carried out with the paddy samples at an initial moisture content of 18.7 to 20.5% (w.b.) and at a depth of 5 to 30 cm. A controlled environment temperature of 43°C was applied in all the experiments. Moisture content of paddy layers were predicted through three parameters of: average moisture content of paddy, layer depth, and total depth of paddy drying in each experiment. Application of two methods of multi layer perceptron network and radial basis function network revealed that the artificial neural network can estimate each layer of paddy moisture content with a coefficient of determination of over 99% thus with a negligible error.

Combined effects of homogenization pressure (0, 50, 150 bar), homogenization sequence (before or after heat treatment), and type of stabilizers (carrageenan, guar and a mixture of carrageenan – guar, either alone or in the presence of starch) on the textural and rheological parameters, including hardness, viscosity, surface tension, syneresis and also microstructural properties of cream – based dairy dessert were investigated. Homogenization pressure of 50 bars after and 150 bars before heating resulted in the highest and lowest hardnesse, respectively. Homogenization pressure of 50 bars after heating led to the highest surface tension, whereas the lowest obtained when applying 150 bars of pressure following the process of heating. Unhomogenized treatments exhibit the highest syneresis, vise versa; the lowest amount was primarily related to the homogenized treatments (after heating) and secondarily homogenized treatments (before heating). Using carrageenan, alone, caused both the highest hardness and the highest syneresis, and in mixture with guar, the highest surface tension. Guar, alone, led to the lowest hardness, surface tension and syneresis. In the presence of starch, hardness was increased using all three combinations of gums, but surface tension was increased through only carrageenan - guar mixture application. Syneresis was decreased applying carrageenan, alone. Microstructure analysis showed good correspondence with the textural and rheological results.

For an investigation, and identification of virulence effect of fungal pathogens of rice striped stem borer, Chilo suppressalis, dead larvae were collected from different rice fields in Guilan province. For isolation of the entomopathogenic fungi, the infected larvae were sterilized by etanol 96% for 1 minute, followed by chlorax 3% for 1minute. Afrer this stage, they were rinsed three times in sterile water. The larvae were placed on wet sterile filter paper in petridishes and incubated in 25.2oC and relative humidity of 85.5% for mycelial growth and sporulation. The fungal colony was formed on dead larvae within 48-72 hours, and sporulation started after 5 to 7 days. The fungi appeared on larvae bodies in white or green coverings. For each fungus, monconidial and purification operation of isolates were carried out on PDA and SDAY media. The Fungi, Beauveria bassiana (Bals.) vuill. and Metarhizium anisopliae (Metch.) Sorok. were identified. In this trial spores of B. bassiana were hyaline, globose to subglobose (2-3.5 × 2-3 mm), while spores of M. anisopliae cylindrical to oval, often slightly narrower in the middle, truncate at both ends, (3.5-9×2-4 mm). Pathogenicity of two species studied by using concentration of (1×106) spores per ml. Sterile water was applied for 15-20 sec. by dipping method on 5th instar of larvae under laboratory conditions. The results revealed that mean mortalities and sporulation of larvae by B. bassiana and M. anisopliae were 75.55, 71.11% and 67.44, 62.22% respectively. No significant difference was observed among treatments involving the two Fungi.

Interaction between artificial inoculation of Meloidogyne javanica and fusarium oxysporum on green and red bean cultivars; Contender and Naz respectively, under greenhouse conditions was studied. A randomized block design with six treatments and four replications was used. Level of inoculums was 5000 j2 of nematode and 1.0 g of mycelia mat of fungus per 800 g of soil. Synergistic interaction occurred between the two pathogens on bean cultivars both in concomitant and sequential (first nematode, then fungus, after two weeks) inoculations. The growth parameters (length of fresh root and shoot, dry weights of root and shoot) reduction was more pronounced with inoculation of either of the pathogens alone. The number of knot formation on root and density of nematode reproduction were very low when inoculation was initially conducted with the fungus then with nematode. The minimum rate of wilting next to control was observed when the plants were inoculated with nematode alone. Maximum wilting symptoms were observed when both nematode and fungus were inoculated concomitantly.

Ultrafiltration can be defined as a pressure- driven membrane process (2-15bar) that can be employed in the separation and condensation of substances with molecular weights between 1-100 KD. The pasteurized, non- homogenized whole milk was ultrafilterd at 50oC, 5 Bar with APV ultra filtration system (51 spirally wound, poly sulfone filter, MWCO=20 K Dalton, DDS) to evaluate all milk of its contents Coefficient of Rejection. Then, total solid, total nitrogen, non- protein nitrogen, protein, fat, lactose, ash, calcium, sodium and potassium were analyzed at a 95% confidence level. The percentage coefficient of rejection for these components were respectively reported as: (55.67±0.695), (93.94±0.89), (5.85±0.39), (99.63±0.24), (100), (0.835±0.21), (31.30±2.89), (59.77±1.18), (9.2±0.77), and (11.47±0.5). The rejection coefficients of milk protein were evaluated through discontinuous SDS-PAGE (10-20% acryl amide), which revealed that a-lacto-albumin, b-lactoglubolin casein and casein hydrolysis contents were respectively rejected as: (96.68±1.725), (99.18±0.46), (100), (98.39±1) through ultra filtration membrane.

Effects of different moisture regimes on soil exchangeable potassium were investigated using 48 soil samples collected from different agricultural areas of Iran. The soil exchangeable potassium was determined after the application of 0, 10 and 20 cycles of wetting and drying and following 10 and 20 days of incubation at field capacity moisture regime. In addition, variations in exchangeable K, following soil incubation at constant field capacity moisture was studied in five soils using 1M ammonium acetate as the K extractant, and in three out of these five soils the exchangeable K was also extracted by 1M sodium acetate. Results indicated highly significant (p<0.1) effects of wetting and drying and also constant moisture regimes on the exchangeable K. The mean increase in exchangeable K after the application of 10, and 20 cycles of wetting and drying, were 17.5 and 19.2 mgkg-1 and the mean decrease in the same parameter due to the incubation of the soils for 10 and 20 days at field capacity were 9.5 and 11.1 mgkg-1, respectively. The reaction of the dry soils to wetting were different; in some soils having low levels of exchangeable K, there was an increase in exchangeable potassium immediately after wetting, while in the others, it either decreased or remained unchanged. When 1M sodium acetate was employed instead of 1M ammonium acetate for the extraction of K, the exchangeable potassium remained unchanged by wetting, indicating that the effect of wetting is on the fraction of K which is not exchangeable by the large hydrated ions like Na+, but it is replaceable by NH4+ ions. This fraction of K is located mainly in wedge zones of 2:1 layer silicates. In all soils, the exchangeable K decreased exponentially with time of incubation at constant moisture. In this study, it was indicated that the results of Olk et al. (1995) method for determination of soil exchangeable K were highly correlated (r2=0.999, 22 soils) with those of Knudsen et al (1982) method.

Seventy seven monoconidial isolates of A. flavus were recovered from pistachio seed and pistachio processing residues at different areas of Kerman province. Nitrate non-utilizing mutants (nit) were isolated on Czapek Dox Agar amended with KClO3 for 48 isolates, with other isolates producing no nit mutants. Phenotype of nit mutants was determined on Czapek amended with various nitrogen sources (nitrate, nitrite, amonium, uric acid and hypoxantine), so that 75% of mutants were found to be nit1, 18% nit3 and 7% nitM. Complementation between nit mutants was tested on Czapek Dox Agar. Twenty one isolates were assigned to four vegetative compatibility groups (VCGs) based on formation of heterocaryon, designated as Af1, Af2, Af3 and Af4, while 27 isolates produced no heterocaryon and did not categorize into any VCG. Sclerotium production ability was analyzed for all isolates in which only 16.6% of isolates were found to produce sclerotium. There was no relationship observed between vegetative compatibility groups (VCGs), sclerotium production ability and geographic distribution. This study revealed that population of the fungus did not show any high level of diversity in Kerman province even though isolates can exchange genetic materials through hyphal anastomosis and formation of heterocaryon.