Agriculture
Ali Zeinadini; Mir Naser Navidi; Mahnaz Eskandari; seyed alireza seyedjalali; Javad Seyed Mohammadi; Aboalhasan Moghimi; ءشاشئئشی ganjehie; alireza moghri; mohammadreza pahlavanrad
Abstract
The objective of this study was to investigate the effect of soil and land characteristics on saffron yield, their rating for preparation of a soil requirements table of this plant for land suitability studies by FAO method. First, 124 saffron farms in Khorasan Razavi, South Khorasan, Fars, Golestan, ...
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The objective of this study was to investigate the effect of soil and land characteristics on saffron yield, their rating for preparation of a soil requirements table of this plant for land suitability studies by FAO method. First, 124 saffron farms in Khorasan Razavi, South Khorasan, Fars, Golestan, Markazi and Kerman provinces were selected. In each field, suitable soil samples were taken and a land use questionnaire was completed during three years from 2017 to 2019. Soil samples were tested to determine their physicochemical properties. After preparing the data, they were statistically analyzed. Multivariate regression between yield as a dependent variable and salinity, percentage of exchangeable sodium, soil reaction, gypsum, lime, clay, sand, silt, gravel and available potassium and phosphorus of soil were studied as independent variables by stepwise method. By examining the relationships of simple regression between important and effective land characteristics and yield, land characteristics rating was performed. Then, the saffron soil requirements table prepared. The proposed table was verified with the data of 21 new farms. The results showed that available potassium, sand, soil salinity, percentage of exchangeable sodium and lime had the highest and the reaction of soil and organic carbon had the lowest range of changes. Regression results showed that the independent variables of soil salinity, ESP, lime, gypsum, gravel and available potassium and phosphorus, respectively, affect yield. Coefficient of determination of multivariate regression showed that the variables entered in the model were able to determine 95% of the variance related to the dependent variable. The largest contribution to the reduction of saffron yield is related to soil salinity, gravel, exchangeable sodium percentage and the amount of lime. Validation results showed that the yield correlation coefficient with the soil index of the proposed table for saffron is about 0.92, which indicates the acceptable accuracy of the proposed table.
Agriculture
Moein Tosan; Amin Alizadeh; Hosein Ansari; Parviz Rezvani Moghaddam
Abstract
Saffron is cultivated in most part of Iran, because of low water requirement and well adaptation to diverse environmental condition. In recent years, for many reasons such as low water requirement, saffron cultivation areas has been increased especially in Khorasan Razavi province. Temperature is one ...
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Saffron is cultivated in most part of Iran, because of low water requirement and well adaptation to diverse environmental condition. In recent years, for many reasons such as low water requirement, saffron cultivation areas has been increased especially in Khorasan Razavi province. Temperature is one of the most important factors in saffron flowering phenomena. The aim of this research was to evaluate the response of saffron to temperature in Khorasan Razavi province counties (Torbat-e-Heydarieh, Gonabad, Nishabour, Sabzevar and Ghoochan). Climatic data (monthly minimum, average, maximum temperatures and diurnal temperature range) and saffron yield data were collected for past 20 years period. The stepwise regression methods were used to remove extra parameters and only keep the most important ones. By using these equations and ArcGIS software zoning, Spline method was find the best for saffron crop zoning. The results of linear regression in Gonabad showed that minimum, maximum and average temperature and also diurnal temperature range in March and April months had the greatest impact on saffron yield. For each of the four indices (the minimum, maximum and average temperature and also diurnal temperature range) the best area for saffron cultivation was the southern part of the province (particularly Gonabad); so by increasing distance from this area to north areas (such as Kashmar, Torbat-e-Heydarieh, Sabzevar, Nishabour, Mashhad and finally Ghoochan) saffron yield reduced by 30 to 50 percent. Therefore, the northern areas of the province had relatively low saffron yield. According to result of this research, saffron yield in Khorasan Razavi province was significantly influenced by temperature parameters. Flowering which basically is the most important stage of plant growth, is directly setting up with temperature.
