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Sedaghati N.,Damghans Pistachio Research Station | Hokmabadi H.,Irans Pistachio Research Institute
Journal of Agricultural Science and Technology | Year: 2015

In this research, some of the echo-physiological characteristics of pistachio trees were studied to understand crop response to drought stress and determine the best irrigation interval. This experiment was carried out in an orchard with a sandy loam textured soil and a commercial cultivar of pistachio named Ouhadi grafted on Pistacia vera L. rootstock for three years. The irrigation system selected was surface flooding with intervals of 30, 50, 80, and 110 days. These intervals were chosen so as to resemble common irrigation intervals of pistachio orchards in the region. This enabled a comparison between the best and worst conditions of trees in respect to drought stress. Total irrigation water received was a constant depth of water to all treatments. Quantitative and qualitative yield such as weight of fresh and dry nuts, percent of blank and split nuts, and number of nuts per ounce, vegetative and echo-physiological characteristics were considered and measured. In terms of yield quantity and quality, the results showed vegetative and echo-physiological attributes to be significantly different between the treatments of 30, 80 and 110 days irrigation intervals. This means that with an increase in irrigation intervals and considering soil water holding capacity, soils were not able to provide enough moisture for the plant to carry out its normal metabolic activities. However, in the prolonged irrigation intervals, there were not much differences between treatments i.e. the pistachio tree could adapt itself to the naturally occurring environmental stress conditions. © 2015, Tarbiat Modares University. All rights reserved. Source

Kamiab F.,Islamic Azad University | Talaie A.,University of Tehran | Khezri M.,Shahid Bahonar University of Kerman | Javanshah A.,Irans Pistachio Research Institute
Plant Growth Regulation | Year: 2014

The protective effects of free polyamines (PAs) against salinity stress were investigated for pistachio seedlings (Pistacia vera cv. Badami-Zarand) in a controlled greenhouse. Seedlings were treated with 25, 50, 100 and 150 mM of salts including NaCl, CaCl2 and MgCl2. Foliar treatments of putrescine, spermidine (Spd) and spermine (Spm) (0.1 and 1 mM) were applied during the salinity period. Results showed that growth characteristics of pistachio seedlings decreased under salinity stress and the application of PAs efficiently reduced the adverse effects of salt stress. PAs reduced the severe effects of salt stress in pistachio seedlings neither by increasing the activities of peroxidase and ascorbate peroxidase nor by increasing the proline content but by increasing the activities of superoxide dismutase and catalase and decreasing the hydrogen peroxide (H2O2) activity. PAs treated seedlings showed a lower Na+:K+ ratio and Cl- in leaves suggesting the role of PAs in balancing the ion exchange and better Na+:K+ discrimination under salt stress condition. These results showed the promising potential use of PAs especially Spm and Spd for reducing the negative effects of salinity stress and improving the growth of pistachio seedlings. © 2013 Springer Science+Business Media Dordrecht. Source

Panahi B.,Irans Pistachio Research Institute | Khezri M.,Shahid Bahonar University of Kerman
Scientia Horticulturae | Year: 2011

The appropriate time of harvest is one of the most important factors affecting the quality of pistachio. Cultivars 'Ahmad-Aghaii', 'Kaleh-Ghoochi', 'Ohadi' and 'Badami-Zarand' were evaluated for qualitative indices of nut over a period of four years from 2001 to 2004. Nut samples were collected during eight successive weeks from 23 August to 11 October. Splitting, early splitting, hull cracking and hulling percentage continually increased toward the last harvest week while non-splitting, immaturity, number of nuts per ounce and moisture content decreased during the harvest weeks. The increment of splitting and the number of nuts per ounce was not significant from 20 September to the last week of harvest. Early splitting, hull cracking and aflatoxin contamination of kernel progressively increased from 13 September. Total crude fat and sugar contents showed a peak in the middle of September. The concentration of aflatoxins prior or at maturity stage of selected cultivars was lower than the critical level. In general, the appropriate time of harvest for the cultivars studied is the middle of September to avoid contamination of nuts to aflatoxin and to ensure the nut quality. This study emphasizes different quality indices for determining the optimum harvest time of pistachio crop. © 2011 Elsevier B.V. Source

Sedaghat R.,Irans Pistachio Research Institute
Acta Horticulturae | Year: 2011

Supply, demand and price forecasting can provide an appropriate context for long running programming of production and exports. Pistachio is the main agricultural produce that Iran is competing with some other producing nations very closely in its production and exports. With regards to the importance of long running programming for pistachio and to avoid any short run decisions, in this research, world price, supply and demand were forecasted for Pistachio from 2006 till 2015. Data on concerned variables during 1986-2005 were collected by visiting governmental organizations and institutions like management and programming organization, agricultural and commercial data sources and also registered data in FAOSAT. Regression, algebraic average, forecasting with supply and demand factors and ARIMA methods were employed to analyze the data collected. Results revealed that the average world export demand will be promoted by 12.5 percent from the first to the second period. Average world supply also will be increased by 36.7 percent at the same time period. Domestic consumption in producing countries will be also increased by 74.4 percent from the first to the second time period. Average world market price will be enhanced with the growth rate of 52.5 percent in the similar time period. Lastly, it is indicated that any new investment in producing nations can be economical if yield doesn't decrease/remain stable and production costs increase with the rate of less than 52.5 percent from the first period to the second one. Source

In order to the determine the low-temperature development threshold and forecasting of harvesting time by the degree-hour on 'Owhadi' cultivar this research was done in Iran's pistachio research institute. First cuttings of 'Owhadi' cultivar were taken in January and for overcoming chilling requirement they kept in 4°C for 900 hours. Then cuttings were divided in five groups, and each group was put in different incubators with 13, 16, 19, 22 and 25°C, respectively. Growth ratio was calculated by the time of swollen to bud opening (50%), then low-temperature development threshold was determined by regression analysis. To determine fruit ripening time, sampling was done every two days from 5 August and ripening percentage (hull removing and percent of open shell) measured and determined best harvesting time when 50% of fruits ripped. Based on the lowtemperature development threshold, effective degree-hours were calculated from March. Model of harvest time forecasting was determined by study on temperature of nine years (1992 to 1997 and 2006 to 2008) in Rafsanjan city and calculating of degreehours based on the low-temperature development threshold. Results showed the lowtemperature development threshold in pistachio is 5.2°C. Study on temperature data indicated in order to 50% fruit ripening; 'Owhadi' cultivar needs 4280 degree-hours. Based on calculating and analysis of data the following model resulted: Total degreehours=1.01 (degree-hour of March) + 0.91 (degree-hour of April) + 5.06 (degree-hour of May) + 1.49 (mean temperature of March) - 0.772 (mean temperature of April). Source

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