فهرست مطالب

Research on Crop Ecophysiology - Volume:6 Issue: 1, 2010

Journal of Research on Crop Ecophysiology
Volume:6 Issue: 1, 2010

  • تاریخ انتشار: 1389/07/01
  • تعداد عناوین: 8
|
|
  • Norair Toomanian, Ahmad Jalalian, Hossein Khademi, Jahangard Mohammadi Page 1
    This paper attempts to estimate and map the clay content of soil Substrata by using some innovative inferences in UK system. Therefore, robustness is inferred in trend analysis and variography of UK system. The variogram parameters are estimated also by maximum likelihood (ML) and restricted maximum likelihood (REML) methods to reduce the probability of biasness of robust variography. A restriction is added to UK system not to predict outside the physical range. Interpolating the clay amount (%) in second soil layer was carried out on transformed (arc sin (y1/2)) data. The landform map was the only remaining fixed effect in the regression model with R2 = 58. The x-validation analysis proved that using RE(ML) methods to estimate the covariance parameters gives more realistic results and avoid the bias existing in robust methods of parameter estimation. Due to non-linearity of back transformation formula of kriging variance, instead of calculating the standard error image the lower and upper confidence interval boundaries of predicted variance was calculated for a 0.975 probability.
  • Mohammad Pasandideh, Fereidoon Nourgholipour, Hossein Besharati Page 11
    Phosphorus is one of the major elements in plant nutrition and crop productivity, participating in many biochemical processes and translocation of energy. In addition, P is a constituent of cell nucleic acids. Application of phosphate fertilizers is a common practice to correct P-deficiency in plants. For a long time, rock phosphate (RP) has been a major source to P fertilizer production. For evaluation of the efficiency of combined rock phosphate with different constituents, a garden experiment, as a completely randomized block design, was carried out in Torough Station of Agricultural Center of Khorasan with eleven treatments and three replications. Each replication included two apple trees (there should be 11 treatments or 22 apple trees in each replicate row). Treatments were: T1: control (without phosphorous use), T2: Using P as triple super phosphate, T3: 40% concentrated R P. + 40% S(powdered) + 16% cow manure (CM) + 4% zinc sulphate, T4: T3 + 20 grams Thiobacillus sp. inoculant (107 cfu g-1), T5: T3 + 40 grams Thiobacillus sp. inoculant, T6: T3 + Tea residues instead of CM, T7: T4 + Tea residues instead of CM, T8: T5 + Tea residues instead of CM, T9: T3 + plant residue compost instead of CM, T10: T4 + plant residue compost instead of CM, T11: T5 + plant residue compost instead of CM. In all treatments, 1 kg of each fertilizer was used for each apple tree at a 40 cm depth. Results indicated that there were significant differences among treatments including concentrated RP + S, Thiobacillus sp. bacteria and CM, with control treatment and treatments with no Thiobacillus from the aspect of available-P and leaves-P concentrations. Based on the results (P<0.05) using of RP + S, Thiobacillus sp. bacteria + CM at a rate of 1 kg.tree-1 for each apple tree had the same effect as triple super phosphate.
  • Majid Shams, Rajab Choukan, Eslam Majidi, Farokh Darvish Page 19
    This study was conducted to estimate combining ability, gene action and proportional contribution of cross components in some maize genotypes under different irrigation conditions. In 2007 in Research Farm of Islamic Azad University, fifteen maize inbred lines as parents, consist of twelve females (No:4-15) and three males (NO:1-3) were crossed to produce 36 F1 hybrids. Parents and their 36 F1 hybrids were evaluated in a RCB design with three replications under irrigation after 70, 90 and 110 mm evaporation from a class A pan in 2008. Results showed both additive and dominance variances were important under drought stress conditions. Gene expression increased with intensify of drought stress. Proportional contribution of lines, testers and their interactions revealed that female line contributed higher compared to male line under drought stress conditions in all studied traits and maternal parents play the most important role under drought stress conditions. The ratio of GCA to SCA variances was less than unity for all studied traits and showed the predominant role of non additive action in the inheritance. In conclusion, it can be suggested that female parents should be considered more for a successful plant breeding programs under drought stress conditions.
  • Gholamreza Zarei, Hossein Shamsi, Sayed Mohammad Dehghani Page 29
    Water deficiency has adverse effect on vegetative and reproductive stages of rapeseed. Hence, the objective of this field experiment was to examine the effects of irrigation intervals on yield, yield components and oil seed content of three autumnal rapeseed cultivars. An annual field experiment was conducted on a sandy-loam soil at the Islamic Azad University, Maybod Branch in 2006-2007. A split-plot experiment carried out in RCBD with four replications. The irrigation intervals were placed in the main plots including: I1: 7 days, I2: 10 days and I3: 14 days and Okapy, Zarfam and Sarigol cultivars were as subplots. Planting date was September 2006. Fertilizer was applied based on soil testing for all treatments. Irrigation treatments were applied on March 2007 after rosette stage and plant were harvested on July 2007. The following measurements were carried out: seed yield, the number of lateral branches, plant height, the number of siliques per plant, the number of seeds per silique, 1000-seed weight and seed oil content. Base on results, there were significant differences in seed yield between the irrigation intervals and cultivars. The I1 and I2 treatments produced a significantly higher seed weight than I3. Sarigol and Zarfam produced a significantly higher seed yield than Okapy. The irrigation intervals and cultivars were not significant on seed oil content. On the I1, I2 and I3treatments seed oil percentage were 37.58%, 38.38% and 35.93%, respectively and on the Sarigol, Zarfam and Okapy were 37.58%, 37.58% and 35.51% respectively. It is concluded from the present study that 7 days interval and Zarfam cultivar produced the highest seed yield.
  • Sayyed Hassan Tabatabaei *, Reza Lalehzari, Negar Nourmahnad, Mostafa Khazaei Page 37
    More than 98 percent of the earth’s drinking water supply comes from groundwater. It needs protection from possible contamination, especially in urban areas where wastewater production is high. Most area of Shahrekord plain is under the cultivation and irrigation water comes from the groundwater. Furthermore, urban sewage discharges to the groundwater, in some parts of the Shahrekord plain. In this study, 18 wells were selected for water sampling. The effects of landuse were evaluated on Total Dissolved Solids (TDS), Total Hardness (TH), Electrical Conductivity (EC), Nitrate (NO3–), Nitrite (NO2–) and Sulfate (SO42-). The samples were selected in different seasons; spring, summer and autumn 2004. A Nested Complete Randomized Design (NCRD) was used for statistical analysis with 18 samples per plot. The results show that there were significant differences (P<0.05) between value of NO3–, NH4+ concentration and EC in farmlands and urban areas. There was no observed any significant difference on the NO2–, pH and TH value. It was higher in farmlands than in urban areas. The result shows that there are a significant difference (P<0.01) on NO3– concentration in different seasons.
  • Manoochehr Messripour, Mohammad Mahdi Gheisari Page 47
    Certain food and feed products are threatened by mycotoxins. Aflatoxins are a group of mycotoxins produced mainly by fungi Aspergillus flavus and Aspergillus parasiticus. There are four major aflatoxins: B1, B2, G1 and G2 that are usually formed together in various foods and feeds. Aflatoxin B1 is known as the most commonly occurring type of aflatoxin and a potent cancer-causing agent. Because aflatoxigenic fungi can grow on a variety of feedstuff at any stage of production, this study was undertaken to determine the presence of aflatoxin B1 in certain foodstuff in Isfahan. From July 2007 to May 2008, ninety seven samples of animal feeds, such as corn, wheat, barley, rice bran, cottonseed bran, dried roughage feed, and recycled bread were collected from Eastern municipal districts of Isfahan. The samples were treated with methanol and aflatoxin was extracted from the aqueous phase with chloroform, and analyzed using the thin layer chromatography (TLC). Nineteen samples out of the 97 analyzed samples were contaminated with aflatoxin B1. Highest number of contamination was seen in recycled bread samples (64%). Bread is probably the food of greatest concern in Iran, because of its predominant consumption. However, the toxin was detectable neither in wheat nor in wheat flour. Contamination of corn, cottonseed bran and rice bran were 38, 25 and 17% respectively. Results indicated that high contamination of recycled bread can be associated with a very poor storage habit. However contamination of corn, cottonseed bran and rice bran may occur during processing and storage.
  • Abbas Kheiri, Mohsen Fatahi Page 55
    Field experiments were conducted to evaluate yield and Verticillium resistance in cotton, 6 cultivars were studied as randomized complete block design with 4 replications in Estahban Research Station, during 2005 to 2006. Disease percent, the index and severity were determinated based on foliar symptoms.Results showed that Bakhtegan, 818 and B-557 had the least percent (20-29.38%),Severity (1.42-1.62) and index (32.13-45.69) of disease.On the other hand, Varamin had the most percent (%85.63), Severity (3.23) and index (278) of disease. Bakhtegan, 818 and B-557 were significantly differed of others in yield.
  • Mohammad Jouki, Naimeh Khazaei Page 61
    Methanolic extract of leaves of Eucalyptus camaldulensis was studied for in vitro microbial activities by agar dilution method. The phytochemical analysis of the crude extract of the medicinal plant revealed the presence of saponin, saponin glycosides, steroid, cardiac glycoside, tannins, volatile oils, phenols and balsam (gum). The methanolic extract of the plant inhibited the growth of Bacillus subtilis and Staphylococcus aureus (ATCC103207 and Clinical strain respectively) but had no inhibitory effects on and Escherichia coli. The minimum inhibitory concentration (MIC) of the extract ranged from 1.25g/ml to 5g/ml. The results obtained suggest that Eucalyptus camaldulensis can be used in treating diseases caused by the test organisms.