Year:2004 | Volume:10 | Issue:3|Papers Count:16

To Study the effect of water deficit stress and potassium application on yield and yield components of canola (Brassica napus L.). A factorial split plot experiment with Randomized complete block design was conducted at seed and plant Improvement institute (SPII), Karaj, Iran during 2001-2002. A factorial arrangement of irrigation interval at three levels (Normal Irrigation, cut of Irrigation from flowering stage, cut of Irrigation from seed filling stage) and Potassium fertilizer at three levels (Normal, recommended ratio, double amount of ratio) were allocated to the main plots and cultivars of Rapeseed (Regentcobra, Quantum, Hyola401) were assigned to the sub-plots. The result showed that the main factors (Irrigation levels, Potassium application Levels and Cultivars) had significant effect (P<0/01) on seed yield, seed oil yield, seed weight, Number of seed perpod and number of podper plant. Normal Irrigation had higher yield (and yield components) than cut of Irrigation from flowering stage. Although in this research is has noted that potassium had important effect on plant resistance to water deficit. The interaction effect between Irrigation and potassium for seed and oil yield and interaction effect between Irrigation and cultivars for seed perpod was significant (P<0/01). The interaction effect between Irrigation, potassium and cultivar was significant (P<0/01) for oil yield and seed yield.

During 2000-2002 a faunstic survey was carried out on aquatic beetles of the family Hydraenidae in Tabriz region (Iran). A total of five species were recorded from this region. Of these, four species which are marked with an asterisk are new records for Iran. They are listed as follows:1. Ochthebius janssensi F.2. Ocllthebius karasui F. *3. Ocllthebius schneideri K *4. Ochthebius inelegans J. *5. Limnebius papposus M. *

Due to nutritive value of tea and its effect on human metabolism is likely to be one of the most common beverages accepted all over the world. To achieve fortification and improvement in quality and quantity of nutrients in made tea, this experiment was proposed. It was conducted by using factorial Split-Plot design, with three factors in three replications in RCBD. Nitrogen and potassium fertilizers were both distributed in two levels in a factorial form in mainplots and micronutrients were distributed in subplots with four levels. In such condition the amount of tea leaf nutrient (included N, P, K, Mg, Zn, Cu) were measured four times, where as the percentage of tannin and caffeine were calculated twice and once respectively. Nitrogen fertilizer showed significant effect on the percentage of tannin, nitrogen, phosphorus, Zn and Cu (at p=5%). Micronutrients application indicated significant effect on percentage of P, Zn and Cu (p=5%, 1% and 1% respectively). Combination of N+K with micronutrients was significant on the caffeine percentage and Cu content (p=1%), where as in both cases, treatment urea + potassium chloride without micronutrients performed the best results.

In 1998 & 2000, two field trails were conducted in the two regions of Karaj & Qazvin in order to evaluate efficacy of chemical, biological and growth regulator compounds against fireblight disease on pear trees, respectively. Results obtained from that study showed satisfactory protection of pear blossoms by both Starner & Boradeaux mixture in combination with mancozeb. In present comparative case study, three forecasting systems namely Mean temperature line, Cougerblight and Maryblyt were used to determine accuracy of the previous phonology-based spray programmes. The metreological data of last month of the winter & three months of the spring seasons of the years 1998 & 2000 were collected from the synoptic weather station of Karaj & Qazvin, respectively. All data required for these forecasting were incorporated into the models. Risk assessment data indicated prevalence of three consecutive infection days in the Karaj at the end of blooming period (19-21 April, 1998). Thus at least two of the four protective sprays on Karaj orchard were applied either unnecessary or inadequately. In contrast, all the three systems predicted six infection risk days in 8, 10, 14-16 & 19 of April, 2000 for the Qazvin. In other words, two of the treatments were met precisely with true infection events. The only failure was with the third (last) spray which was applied two days earlier than the predicted infection days during 14-16 of April, 2000.

Evapotraspiration (ET) is the base of water management, design of irrigation systems capacity and hydrological studies. Requirement for ET data has caused various ET estimation methods to be developed. Therefore, on the basis of a region's climate, the best reference evapotranspiration estimation method must be selected to design engineering projects. In this research, by selecting the FAO-Penman-Monteith as the standard method, validity of ETo data based on Hargreaves-Samani, Makkink, Turc and Papadakis methods (which have simple equations) was evaluated for different climates of Iran. In the Demarthon method, Iran's climate is divided to 8 classes: very arid, desertarid, semi-arid, Mediterranean, semi-humid, humid, very humid kind A and very humid kind B. For each climate-(except semi-humid climate), a synoptic meteorological station was selected. Results indicated that ET0data estimated by Hargreaves-Samani method in desert-arid, semi-arid and Mediterranean climates and by Turc method in very arid, humid and very humid kind B climates and by Makkink method in very humid kind A had the best correlation and the least error with FAO-Penman-Monteith method, respectively. For monthly mean of daily ETo data, estimation by Hargreaves-Samani method in desert-arid and semi-arid climates and by Makkink method in Mediterranean, humid, very humid kind A and very humid kind B climates and Turc method in very arid climate had the best correlation as well as the least errors with standard data. To reduce the difference between daily ETo data which had been estimated by simple equations and FP-M equation as well as monthly mean of daily ETo data, 50% of daily ETo data was corrected by using regression equation. As results showed, the differences reduced. Papadakis method did not have these features in any climate.

In this study the effects of temperatures stress and manitol pretreatment on microspore cultures response and viability of microspores have been examined in three popvlations of F3 (Alpha/Yazd -5, Arigashar/Yazd -5, Arigashar/Alger) and cultivar Igri. Spikes were sampled when the distance from the base of flage leaf to the penultimate leaf was 2 to 5 cm in winter genotypes and 5 to 10 cm in spring genotypes. In cytological observation, most microspores in the anther of central floret of each spike were at the mid to late uninucleate stage. The physical appearance of the spikes at this stage depends upon the genotype and the environment where plants are grown. Three pretreatment were investigated in first study.l.cold pretreatment of spikes: Spikes were pretreated during 28 day indarkness and at 4°c. 2. pretreatment of spikes in manitol: Spikes were placed in plate with fifteen ml of 0.3 M Ice cold manitol and kept in the fridge at 4°c for 4-7 days. 3. pretreatment of anther: Fresh anthers were pretreatmented in 5 cm plates with 0.3 M manitol solution at 25°c (3-4 days) in PH=7.00. 200 anthers of central part of each spikes were constituted one replication. In this experiment mechanichal isolation blending method was used to isolate microspore. FHG liquid media (Hunter 1988) with 10 mg/lit PAA (phenyl acetic acid) was used for barley microspore culture. Genotype differences and pretreatments effect were highly significant in microspore viability and their response proportion. There was a very singnificant intraction pretreatments and genotypes according to the percentage of embryo like structure although this subject was not significant for viability of microspores. In second study the influence of temperature stress on microspore culturesresponse and their viability of microspores in cultivar Igri has been examined. Spikes were pretreated in darkness at 4°c for periods of 7,14 and 28 days. According to viability of microspores and microspore culture responses cold pretreatment differences were singnificant. In third study significant differences were observed between four mechanical microspore isolation methods: (Vortexing, Blending, Stirring and Maceration) according to the number ofreleased microspores from each anther, number of relesed viadle microsporespr anther an in number of divided microspore per anther. Finally, in forth study, the influence of concentration of PAA on microspore culture response in four genotypes has been examined. Genotype differences and various concentration of PAA were highly significant in microspores response proportion. There was a very significant intraction between genotype and hormone concentration. Attentive to results it seems that pretreatment of anthers in manitol mechanically isolation method ofvortexing, concentration of 10 mg flit PAA in FHG media are sutible in microspore culture of barley. Ina routin breeding program such as produce doubled haploid, genetic engineering, mutation and selection, the proportion of response of microspore culture is suitable enough.

As a new product, MDF has superior application properties and has recently welcomed by both international and national markets of wood based composites. Consumption history of this product is limited to the last eight years and has been supplied through importation. Production of MDF has been initiated in Iran from 2004, and is growing with regards to the under construction projects. Due to the similar properties of MDF and particleboard, MDF can replace particleboard in various applied cases in national and international scale and is increasing rapidly. Concerning the growing consumption of MDF in Iran in the recent years, and also the local manufacturing of this product, rapid growing of MDF consumption in the country is expectable. Moreover, reviewing the consumption of MDF and particleboard in the last years indicates a higher consumption growth rate of MDF compared to particleboard. Results show that in the lignocellulosic based composites market of Iran, MDF has increasingly substituted particleboard in some applications. In addition, consumption growth rate of particleboard has been affected by the consumption growth rate of MDF, and the substitution rate of this new product is increasing.

SIRMOD model is more suitable tools for evaluation of irrigation systems that must be tested and evaluated before use in practice. Sensitivity of SIRMOD to input parameters in three solution methods of Saint- Venant equation was evaluated with ±25% of input parameters variation. Sensitivity analysis results was shown, model is more sensitive to input parameters in advance phase and runoff volume than other parameters (Slope, roughness coefficient and furrow geometry). Model in infiltrated water volume is more sensitive to infiltration equation coefficient and inflow respectively, than other input parameters. SIRMOD isn't sensitive to solution methods of Saint-Venant equation. Sensitivity of model is variable with soil type. The percent of input parameters variation isn't effective in sensitivity order. Therefore, the parameters must be measured with maximum accuracy consist on inflow and soil infiltration coefficients.

This study was carried in 1999 in Damavand region, as factorial in a randomized complete block design of a planting depth on yield of 3 potato cultivars. In this experiment the cultivars (pashandy, aola, and ponda) and the planting depths(15,20,30,and 40 cm) were of A and B factors respectively. All agronomical characteristics of the plants were evaluated during the growing season and the data were recorded during growing period and analyzed statistically. The results showed a significant difference between cultivars and planting depths. Also the results showed the aola cultivar and 15 centimeter planting depth were superior than the others. Finally it is recommended that the superior cultivars like aola to be planted in 15 cm planting depth in this region and the similar region in order to increase the yield of potato.

Regarding to unbelievable recent technology developments, one can observe the progress of science in the fields such as agriculture and industry due to application of computerized systems. Performance and ability of computer causes that challengers accept this phenomena in any ages and receive its services. Agricultural industry has benefited from this technology too. In fact designing an expert system is creating an intelligent computer software which is able to suggest the best way in a systematic and exact manner with bounded knowledge. It goes without saying that its possible to design expert systems in any branch of sciences. In this article design of an expert system in selecting primary tillage tools has been discussed. Developed multiple language, is efficient for the whole country to day. It is enough to show your location on the map instead of answering some of the questions for KARAJ (its hemisphere information exists in the software). These facilities is extendable for the world. The structure of the software for selecting the empliments is done on the basis of weighting different parts of the name of the complete implement by fuzzy logic lables and data fusion and its result is a list of proper tillage implements for that special situation given by the user. This list is sorted by the priority of implements and the pictures and explanations as well as the name of the implement will guide the user.

In order to determine the effects of narrow row spacing on vegetative and reproductive characteristics of bean (Phaseolus vulgaris), an experiment was conducted in Khomein National Bean Research Station for two years (1998-1999) as split block design in randomized complete block with three replications. Three bean genotypes (C.O.S-16, Akhtar, WA4502-1) in verticl plots and four row spacings (50, 37.5, 25,18.75 cm) in horizontal plots were studied. Combined analysis of variance of experiment revealed that genotypes had significant differences in plant height, days to flowering, days to maturity, pod filling period, 100-seed weight and grain yield. C.O.S-16 had the highest plant height. Furthermore, this genotype had greater growth period than the others. Mean grain yield of spotted bean (C.O.S-16), red bean (Akhtar), and white bean (WA 4502-1) were 2569, 3050, and 2230 kg/ha, respectively. Row spacing significantly influenced the traits of days to flowering, days to maturity, pod filling period, 100-seed weight and grain yield. The greatest grain yield, up to 2971 kg/ha, was obtained from 37.5 cm row space.

Studies show that in 80 percent of unsuccessful drainage projects, the reason is improper subsurface drainage envelope design and installation. Thus, proper envelope design and installation is more important than other subsurface drainage design parameters. Gravel envelopes which are generally used in projects has some limitations in prepation, transportation, installation. That's why the use of synthetic envelopes developed in some countries. Synthetic envelopes or geotextiles have no problems such as the ones expressed above for gravel envelopes. In this study two kinds of non-woven synthetic envelops were made of polypropylene and polyacrile filaments, then an unstable soil with sandy loam texture was selected. After determining the properties of soil and geotextiles, the best geotextile was selected for this soil by permeameter testing. The results of geotextile and gravel envelope investigation in compare with each other in soil-water tanks showed that the ratio of average outlet discharge of drains with geotextile envelope to gravel with different hydraulic heads(30, 60 and 90 cm) were 0.83, 0.72 and 0.6 respectively. It shows that geotextile discharge is lower than gravel. In addition, the resistance of geotextile to water current is more than designed gravel envelop.