Year:2002 | Volume:8 | Issue:1|Papers Count:10

In modern agriculture, the first step in organic production, is the elimination of chemical residues. In this hio-management system, the substitution of agrochemicals (eg: pesticides, plant hormones, chemical fertilizers, etc.) was based on the use of biological agents and soil organic matters, that are considered as majer principles and the basic method.The agricultural management of organic system consist on, of not using any kind of chemical materials in: farms, fruit orchards, especially on apple tress. For this reason, in organic plant protection programmers, the first step was to avoid the use of pesticids.The cultivation of apple orchards in Iranian plateau, which possess different climatic regions and elevations, is well developed. Accordingly apple trees show much adaptation to such variations. Therefore the fauna of apple pests and their natural enemies show a great biodiversity, and they also occure on other Pomoidea. (pear, quince) and Prunoidea (plum, peach, ...).Such bioecological adaptation and biodiversity are important factors in biocenotic potentiality of apple orchards, especially in late maturing varieties of apple (Red and Golden delicious), and it has created rich community of natural enemies in our IPM programmers. The bioregional relationship of apple orchards fauna in different parts of Iranian plateau (Khorassan, Azerbayjan, H'), provided us the basic element in our research project to develop an IPM programms for organic production strategy by eliminating the use of agrochemicals. For this purpose we included both applied as classic and natural biological control to deal with the following important and cosmopolitan pests:-Cydia pomonella (L) (Lep. Tortricidae, Olethreutinae)(Synonyms: Carpocapsa =Laspeyresia)-Leucoptera scitella (Zell) (Lep. Lyonetiidae)- Eriosoma lanigerum (Hausm.) (Horn. Aphididae)- Aphis pomi DeG. (Horn. Aphididae)- Panonychus ulmi (Koch) (Aea. ri Tetranychidae)- Podosphaera leucotricha Salmon (Erysiphaceae- Ascomycetaceae)In the text of the above IPM programme for controling Cydia pomonella, in its different developpemental stages, such as: egg. larva, adult, and at the 2-4 annual generations, the following methods and materials were used:- Inundative release of Trichogramma spp. - Other biotic agents (Carpovirusine and Sex pheromon traps ...)- Mechanical method by installing belt trap on tree trunks.In this integrated control, to reduce the population density of codling moth, the level of economic damage was lowered to the range of 0.8 to 12.07%.In monitoring the population growth rate of other potential pests (European red-mite, leaf mining moth, aphids, ...) we provided support for their parasitoids and predators by protecting green coverage under trees, regular Irrigation. Practicing winter oil spray, and if necessary, at the time of growth, in spring, and even during the summer time, and excluding chemical pesticides use.Referring to IPM in apple orchards, and their faunistic studies in different regions of Iranian plateau, during 1990 -99 researches were carried out on the following key species parasitoids and predators in our IPM programmers:- Trichogramma embryophagum Hartig. (Hym. Trichogrammatidae)- Tetrastichus amaethystinus Ratz. (Hym. Eulophidae)- Lasiopticus pyrastri L., Epistrophe balteata, ... (Dip, Syrphidae)- Chrysoperla carnea Steph., Chrysopaseptempunctata, (Neur. Chrysopidae)- Oriou.'Ihorvathi (Reuter), O.bulgaconus, ... (Het. Anthocoridae)-Harmonia congfubata, Stethorus punctillum Weise (Col. Coccinellidae)-AeolothripsintermediusBagnall. (Thys.Aelothripidae)In conclusion: The biocenotic potential of apple orchards in Iranian plateau, and thecosmopolitan aspect of mentioned species, provide an opportunity to develop IPM programme, for production of organic apple in national level.

In 1999 a factorial experiment was conducted in khodabandeh Dryland Research station to study the effects of foliar spraying of urea, potassium chloride and urea + potassium chloride on grain yield, grain protein and leaf relative water content of Sardari wheat under rainfed condition. Also to determine the most effective time of application the nutrients is used at various growth stages including double ridge stage, pollination stage, milky stage and double ridge stage + milky stage. The factorial xperiment had 15 treatments and arranged in a randomized bolck design with three replications. The amounts of urea and potassium chloride used for foliar nutrition were equivalent to 20 kg Nand 20 kg K20 per hectar respectively. The urea and potassium chloride were sprayed with concentrations of 5% and 1% respectively. The results obtained from this experiment showed of growth preserved leaf moisture and resulted in highest leaf relative water content. Spraying potassium chloride + urea in double ridge and milky stages resulted in highest grain yield (1221 kg/ha), biological yield 3616 kg/ha, thousand kernel weight (34. 33 g), number of kernel per head (19.4) and grain protein content (16.7%). These parameters showed 40%, 9.3%, 49% and 7.9% increase when compared with the check of treatment respectively. The overall results showed that spraying potassium chloride before anthesis stage increases grain yield and number of grain per head, while spraying after anthasis stage increases significantecy protein content and thousand kernel weight.

In order to investigate effects of salinity on quantitative yield, ion uptake and transportation a farm experiment was done. The experiment was conducted for two years (1999, 2000) at the pistachio production station in Gonabad, Khorasan. Two orchard of pistachio farm with different levels of Eciw. were selected for this study. The cultivars of Badami riz (Sefid) and Fandoghi (ohadi) which have previously been budded on Badami -riz formed scion – rootstock combinations. This experiment was done in the form of randomized complete block design with repeated measurement. The following results obtained:Sodium content of leaf tissues was increased in Fandoghi as compared to Badami, Significantly. The Cl‑, Ca+2 ,Mg+2 and especially Na concentrations in leaves showed an increase beyond the normal range. The results of combined analysis in two years and two pistachio production units showed that the quantitative yield of Badami is significantly higher than Fandoghi.

In this research, during different seasons of a year, effect of cream separation, two-stage bactofugation and pasteurization were studied on cheese milk microbial load reduction in a cheese production line using ultrafiltration technology. Results showed that related to microbial load reduction, preheating of raw milk in regeneration section of pasteurizer; centrifugal force in cream separator and bactofuges and heat treatment during pasteurization have considerable effect and the efficiency of different unit operations is affected by months and seasons. In addition, in different months of year, microbial population of raw milk has considerable alterations. The higher milk supply during the summer in comparison of other seasons, and some other factors related to the milk collection are at the origin of these changes. The efficiency of different apparatus in term of microbial load reduction are: 20-70% for cream separator, 60-90% for first bactofuge, 55-85% for second bactofuge and 92-98% for pasteurizer.

In this research the functional response of Encarsia lutea (Masi) and Eretmocerus mundus Mercet as important natural enemies of Bemisia tabaci (Genn.) nymphs were studied. Parasitoid were wllected from Varamin and Garmsar cotton fields and studied on B. tabaci nymphs, in a growth chamber at 15, 25 and 32°C, 60±5 % R.H. and 16:8 (L:D) photoperiod.Individual parasitoid females were provided with 2, 4, 6, 8, 10, 12, 14, 20, 30 and 40 third nymphal instars for a 24 hours period. Mean number of parasitized nymphs by E. lutea and E. mundus on minimum and maximum host densities ranged from 1-4.4 and 0.4-3.8 at 15°C, 1.2-7.1 and 0.8-5.6 at 25°C and 1.4-6.4 and 1-6.4 at 32°C, respectively. E. lutea and E. mundus showed a type H functional response to the third nymphal instars of B. tabaci. Searching efficiency was 1.083, 1.828 and 2.972 in E. lutea and 0.674, 0.988 and 0.797 in E. mundus at 15, 25 and 32°C, reservedly Handling time at the same temperatures was 0.184, 0.108 and 0.125 in E. lutea and 0.135 and 0.105 in E. mundus. In comparison of natural enemies, each species that Has higher searching efficiency and lower handling time is more effective in control of it's host. On the hasis of this idea, E. lutea has more capacity than that E. mundus in control of B. tabaci.

The effects of drought and potassium application were studied on quantitative and qualitative soybean (Glycine max L.) characters in a split plot design. Drought and potassium levels were set as main plot and sub-plot, respectively. Node number and inter-node length were declined that caused plant height to be decreased. But the effective factor on seed number declining was seed number per pod at medium stress. However, both of them caused to decreased seed number at sever stress. Drought occurrences at reproductive development stages not only induced flower abortion but disordered assimilate synthesis and its translocation. Seed weight was decreased hy drought. Potassium helps plant to conserve water potential in the cell and inhibited to waste water. At, drought treatments, potassium caused photosynthesis to conserve. However, there were no significant difference on yield and its components, but when stress was more sever pod and seed number per plant were increased where potassium was applied.

The major purpose of this study was to assess the factors that affect the usefulness of informal technical and vocational education courses for working forces in rural arae of Tehran Province. The population for the study was 43 practitioners, 51 trainers and 1777 trainess which attended in 99 deferent educational courses for 1998.The study used applied research and the researchers gathered information by interviewing the population. The dependent variable in the study was usefulness of educational courses and 31 different independent variables was selected.The results show that there were meaningful relationship between dependent variable and age of trainee, present occupation of trainees, using the educational materials by the trainess, final scores of trainees after completing the educational session, length of courses and time of classes.The result of study also indicated that there were no relationship between dependent variable and trainers educational level, trainers teaching experience, gender of trainee, using the course syllabus and number of hours allocated for each classes.The regression analysis revealed that the variables such as income, educational level of trainee had negative impact on usefulness of courses. The results from factor analysis showed that seven factors such as appropriate training content, educational level as well as working experience of trainers and practitioners influenced the usefulness of the training courses.