h. dialami

In order to investigate the effect of water stress and the application of potassium sulfate fertilizer on some growth characteristics of "Zahedi" date palm tissue culture-derived plants, this research was conducted as a factorial experiment based on a Randomized Complete Block Design with three replications on 45 plants. Water stress at three levels (Irrigation to the amount of 100, 80 and 60% of cumulative evaporation from Class A evaporation pan) and potassium sulfate fertilizer at five levels (zero, foliar application 2 g L-1 and 4 g L-1, soil application 50 g and 100 g for each plant) were applied to the plants. At the end of the experiment, the growth characteristics including trunk circumference, number of leaves, length and width of leaves, number of leaflets, length and width of leaflets, fresh and dry weight of aerial parts were measured and subjected to statistical analysis. The results showed that the increase in water stress had a significant negative effect on all vegetative growth traits, while the application of potassium sulfate moderated the effects of water stress. At the highest level of water stress (Irrigation to the amount of 60% of the water requirement) without application of potassium, the fresh and dry weight of aerial parts was recorded at 590 and 243 g respectively, but with the soil application of 100 g potassium sulfate at the same level of water stress, the fresh and dry weight of aerial parts increased significantly to 706 and 346, respectively. In this research, the soil application of potassium sulfate fertilizer had better effects on the growth characteristics of date palm plants than the foliar application method. In all levels of water stress, the application of potassium sulfate fertilizer, especially in soil application of 100 g for each plant, increased vegetative growth and fresh and dry weight of the date palm plant and improved its resistance to water stress.

This research was conducted to investigate the effect of potassium sulfate application on some physiological characteristics of tissue culture-derived date palm plants under water stress conditions. The study was conducted as factorial experiment based on a randomized complete block design with three replications. After complete establishment of plants, potassium sulfate at five levels (zero, foliar application of 2 and 4 g L-1, soil application of 50 and 100 g for each plant) and then water stress at three levels (100, 80 and 60% of cumulative evaporation from Class A evaporation pan) were applied. The results showed that with the application of potassium sulfate at high levels of water stress, the chlorophyll index increased and ion leakage percentage decreased. In the third level of water stress without application of potassium, the chlorophyll index was recorded at 42.61, but with the soil application of 100 g potassium sulfate, the chlorophyll index significantly increased to 58.78. The ion leakage of 34.75% was also observed at the third level of water stress without the application of potassium sulfate, while with the application of 100 g potassium sulfate, it reduced significantly to 25.42%. The potassium concentration in leaves in the treatment without potassium application was 1.61%, while in the treatment with soil application of 100 g of potassium sulfate, the value of 1.88% was recorded with a significant increase. Overall, soil application of 100 g of water-soluble potassium sulfate for each plant had the best results in terms of the physiological responses of date palm plant in dealing with water stress conditions.

This research aimed to evaluate the qualitative land suitability for irrigated cultivation of Date Palm (Phoenix dactylifera L. cv Kabkab) using FAO (parametric -the second root formula) and Multi-criteria approaches. The FAO approach has been used by many scholars in different parts of the world and Iran for land suitability assessment. In this approach, the most commonly used method is the parametric method. The FAO approach uses Boolean logic to assess land suitability. This logic has been criticized by a number of land evaluation researchers. Because it does not take into account the continuous nature of the soil variations along the earth's surface and the uncertainty in the measurements. To overcome these shortcomings, the fuzzy analytical hierarchy process (FAHP) was presented to determine the land suitability classes. Land suitability should be determined based on a fuzzy analytical hierarchy process, in which, unlike the Boolean logic, unequal importance of different land characteristics and continuity of soil variations are considered.

The studied area is located in Kheshet and Komaroj plain, Kazerun County, Fars province, southwestern- Iran; between latitudes 29º 32΄ and 29º 36΄ N and longitudes 51º 20΄ and 51º 22΄ E. Its surface area is 5000 ha. The mean annual rainfall and temperature are 377mm and 23 °C, respectively. The soil temperature and moisture regimes are hyperthermic and xeric, respectively. The physiographic unit is river alluvial plain with a very gently sloping. The entire Kabkab date palm plantation of Fars Province is located in this plain. To fulfill the objectives 10 date palm groves, each with an area of at least 0.5 ha and palm date (Kabkab cultivar) cultivation, aged between 20 and 25 years, identical in soil management and vary soil characteristics were selected. A soil profile was dug randomly in each date palm grove, with dimensions of 1.5 (length), 1(width) and 1.5 (depth) meters and described, using soil profile description (Soil Survey Staff). Soil samples were collected from each horizon. After pre-treatments soil samples were analyzed and some physical and chemical characteristics were measured using standard laboratory methods. The profile site was chosen to have a date palm tree in each of the four corners of the profile. The yield of the four trees in four corners of each profile was measured and their average yield was considered as the yield of the corresponding profile. Meteorological data was collected for a period of 10 years from the nearest synoptic station (Kazerun). Land indices were calculated, using soil and climatic data and FAO (parametric-second root formula) and fuzzy AHP and AHP methods. Weighted average of the climatic and the soil data were used and a land index was calculated for each soil profile. In the fuzzy AHP and AHP methods, relative weight of each of the studied criteria was determined by analytical hierarchy analysis using a pair wise comparison matrix. In the fuzzy AHP method the membership degree for each soil and climatic criteria was determined through an appropriate membership function and finally, land suitability class for each soil profile was determined. Landscape characteristics such as slope, drainage and soil depth were not considered in the land evaluation, because these characteristics did not show any limitation for the date production in the studied area. Finally the accuracy of the methods was compared.

The results of qualitative land suitability evaluation based on FAO (parametric-second root formula) method showed that about 10 and 90 percent of the studied area were classified as S2 and S3, respectively. Based upon fuzzy AHP method, 100 percent of the studied area was classified as S2 and according to AHP method about 90 and 10 percent of the studied area were in S1 and S2, respectively. According to the results, the suitability classes resulted from AHP method was higher than of the fuzzy AHP and FAO methods. Correlation coefficients between the measured yields and the calculated land indexes showed that the fuzzy AHP method results were more correlated to the measured yield than of the other two methods which indicated that the fuzzy AHP was the most appropriate method for land suitability assessment for Kabkab Date palm plantation compared to the FAO (parametric-second root formula) and AHP methods.

According to the results of this research, the fuzzy AHP was the most appropriate method for qualitative land suitability evaluation for Kabkab Date compared to the other two methods in Fars province, Iran