جستجوی مقالات مرتبط با کلیدواژه « خرما » در نشریات گروه « کشاورزی »

The date palm (Phoenix dactylifera L.) plays an important social, environmental, and economical role for many people living in arid and semiarid regions of the world. Date fruit is one of the major agricultural crops in the East Asia region, where about 90% of the world's dates are cultivated. Dates are rich in certain nutrients and provide a good source of rapid energy, due to their high carbohydrate content (70–80%). Moreover, date fruits contain fat (0.20–0.50%), protein (2.30–5.60%), dietary fibre (6.40–11.50%), minerals (0.10–916 mg/100 g dry weight), and vitamins (C, B1, B2, B3, and A) with very little or no starch. In addition to the direct consumption of the fruit, various industrial products are also extracted derived from this product, including date juice, date honey, liquid sugar, vinegar, alcohol, caramel, date paste and date chocolate. The annual production of one million and 400 thousand tons of dates in Iran has made Iran the second pole of date production in the world after Egypt. Zarin Dasht region is located in Fars province, and the annual production of dates in this region reaches more than 1000 tons. The aim of the present work was to investigate the chemical composition, carbohydrate, and antioxidant capacity of two cultivars of Zarin Dasht dates.
 
After collection, all date fruits were washed with tap water, and the seeds were then removed, and the flesh were shade dried at room temperature. The dimensions and area of the imaged surfaces were measured by the physical properties measurement device in 100 repetitions. The working principle of this device is based on image processing technique. By placing the product in three different positions and perpendicular to each other, pictures of the date samples were taken individually. Date mass was obtained using a sensitive digital scale with an accuracy of 0.01 g. The displaced water method was used to determine the volume and density of each date seed. Bulk density, date porosity, geometric mean diameter, sphericity coefficient and surface area of the samples were determined. The amount of moisture was determined by weight method, ash by burning in an electric furnace, titratable acidity based on malic acid and pH of the samples were measured by a digital pH meter. To measure the amount of total phenol in the fruit, Folin–Ciocalteu reagent was used and the absorbance of the reaction mixture was read at 750 nm by a spectrophotometer. The amount of total phenol was reported in terms of gallic acid. The antioxidant capacity was determined through the neutralization of free radical 2 and 2 diphenyl 1-picrylhydrazyl (DPPH). To measure the sugar of all samples, first a standard curve was drawn from the glucose solution in different concentrations, then the sugar content of the samples was measured in milligrams per gram of fresh weight at 490 nm using the sulfuric phenol method. The amount of crude fibre was calculated according to the standard method of AOAC-991/43. The amount of fat was obtained with the Universal Extractor E-800 device for 3 hours at a suitable temperature and in 250 cc of n-hexane solvent. Finally, the statistical analysis of the data was done factorially and in the form of a completely random design in 3 replications using SAS 4, 9 software and the comparison of the means was done using the LSD test at a probability level of 1%.
 
According to the results of this research, there was a significant difference in all qualitative traits except pH (P<0.01). In comparing the characteristics of the palms of two cultivars, it was observed that the highest amount of fibre (1.78 %), titratable acid (0.59 %), ash (1.64 %) and fat (0.85 %) is related to Shahani cultivar,and the highest amount of total phenol (8.1 mg/gFW), DPPH inhibitory property (13 %), moisture (18.7%), sugar (63.8 %), protein (0.29 %) and pH (5.74) belonged to Khassui cultivar. Also, comparing the kernel characteristics of two cultivars, it was observed that the highest amount of ash (3.17 %), total phenol (10.8 mg/gFW), antioxidant property (72 % DPPH inhibition), protein (2.55 %), pH (6.11) and fat (9.20 %) related to the kernel of Shahani variety and the highest amount of fibre (26.2 %), moisture (5.26 %), sugar (15.8 %) and titratable acid (0.38 %) belonged to the kernel of Khassui cultivar. Overall, the kernel of Shahani variety had more DPPH inhibitory power among all the samples.

This research was carried out to investigate the effect of preharvest bagging, with different bag types, on the quantitative and quality characteristics of palm date fruit cv. Medjool (25-26 years old trees) in the date palm and tropical fruits research center under Ahvaz weather conditions in 2020 and 2021. The experimental design was randomized complete block design with seven treatments and eight replications. The studied bag types included kraft paper, black, white, and blue cloth, green greenhouse net, straw bag and control (without bagging). Bagging was applied in the khalal stage, and the ends of the bags were open and they remained on the tree until harvest time. The results showed that the weight of bunch, rutab weight bunch-1, tamar weight bunch-1 and the final fruit yield tree-1 were affected by the bag type. Bunch weight, rutab weight and tamar weight in each bunch and final fruit yield tree-1 in all treatments were more than the control. The highest bunch weight (5.69 kg), tamar weight bunch-1 (2.12 kg) and final fruit yield tree-1 (29.3 kg) related to green greenhouse net bag and the highest rutab weight bunch-1 (0.86 kg) related to blue cloth bag. Acidity (pH), titratable acidity (TA) and soluble solids content (SSC) of fruits were not affected by bag type. In general, the green greenhouse net and straw bags were more effective in increasing the final fruit yield tree-1 and reducing the population of eggs, nymphs and adults of Date palm mite.

Foreign trade is one of the important factors in economic development and provision of foreign exchange revenue. In recent years, the existence of price fluctuations in the oil market has faced many changes in the country's foreign exchange income and has affected the country's economy. And this shows the necessity of diversifying export products and trade and emphasizing the importance of trade in non-oil products. Therefore, it is inevitable to focus on the trade of the agricultural sector with regard to goals such as self-sufficiency and food security and the possibility of high foreign exchange earnings in the said sector. Dates are one of the most important non-oil items in Iran, which have a long history. In terms of date history, Iran has always ranked first in the world.

In this study, the short-term and long-term effect of the real exchange rate, date production and the ratio of the domestic price to the world price on the export volume of this product using the ARDL model and the error correction model (ECM) in Iran during the years 1370-1400 were estimated. Investigating the long-term relationship between model variables, short-term dynamics of the model and the adjustment speed of the short-term to long-term imbalance has been estimated.

The results show that in the short term, the ratio of domestic to foreign prices has a positive and significant relationship on the amount of date exports, and in the long term, the ratio of domestic to foreign prices and the exchange rate have a positive and significant effect on the volume of date exports. Also, the results indicate the existence of a long-term and significant relationship between the variables of the model.

Since the exchange rate has a positive effect on the export of dates, with the increase in the exchange rate, the income from the export of dates increases, and this increases the motivation of exporters to increase the amount of date exports. Reducing currency deviations will increase the export of dates, so it is recommended that the country's foreign exchange policies be adopted to support exports and reduce imports of agricultural products. In this regard, prevention of exchange rate fluctuations as well as clear information about the future trend of exchange rate changes will play an effective role in increasing exporters' income and the amount of exports and maintaining Iran's position in global markets. The ratio of the domestic price to the world price in the long term has had a significant effect on the amount of date exports at level 10%. If the government's policy is to reduce exports based on various policies, especially the preservation of water reserves, an increase in the domestic price compared to the world price (through export duties) is suggested.

Date palm is one of the important crops mainly grown in the arid regions of the Middle East and North Africa as well as in the southern warm and dry areas in Iran. One of the most important factors that reduces the quality and commercial value of date fruit is sunburn disorder during fruit growth and development. Therefore, this research was carried out to evaluate the effect of kraft paper, black, white, and blue cloth, green greenhouse netting, straw bag, and without bag (control) at the khalal stage on the ripening rate and sunburn incidence of cv. Medjool using randomized complete block design with eight replication in in Umm al Tameir research station, date palm and tropical fruits research, Ahvaz, in 2020 and 2021. The bags' ends were open and remained on the trees until harvest. The results showed that the bunch weight, the kimiri, khalal and date fruits proportions were affected by year. In 2021, average bunch weight (5.83 kg), kimiri percentage (8.6%) and khalal percentage (28%) were more than 2020, while in 2020 the percentage of date fruits (10.48%) was more than 2021. The rate of kimiri at harvest was lower in black cloth than in others bags. In 2020, bunch bagging with green greenhouse netting, white cloth, and kraft paper increased rutab rate by 9.81%, 12.99% and 11.37%, respectively, as compared to control. Bagging did not affect fruit size and weight. All kind of bags decreased the incidence of sunburn disorder. Kraft paper bag significantly decreased the percentage of dried fruits to 6.78% as compared to control with 9.93%. The rate of fruit decay was not affected by bagging. Considering the results of this research, it was concluded that black and white cloth bags were more effective in reducing sunburn disorder and fruit decay rate of palm date fruit cv. Medjool.

The date palm (Phoenix dactylifera L.) belongs to the family Arecaceae is a dioecious trees. Due to the problems of non-overlapping flowering of some male and female palm trees, commercial date production requires artificial pollination. Temperature is an important environmental factor influencing the pollination, fertilization and fruit set of the date palm. Availability of efficient male pollinators are of great importance in date palm production chain and for regular yearly bearing as the quantity and quality of pollen is a yield determining factor. The flowering and pollination period of date palm varies upon cultivar, geographic location and climatic conditions. However, frequent asynchronous flowering of date palm male and female trees occur due to climatic changes and abiotic stress. In such cases, farmers may pollinate their trees with pollen of a known male conserved at ambient conditions from the previous season; however, this is mostly result in a low fruit set and yield.

In this study, a factorial test was performed based on a completely random design with three replications at the laboratory of the Horticulture department at Ilam University to determine the rate of germination in five male date palm cultivars. The first factor consisted of nine temperature levels of 15, 18, 21, 24, 27, 30, 33, 36 and 39 and the second factor referred to the cultivar of the pollinator which had five levels of ‘Ghanami Sorkh’, ‘Ghanami Sabz’, ‘Sabz Parak’, ‘Nare Pakutah’ and ‘Khareji’. The pollen of the above-mentioned cultivars was obtained from the date palm Germplasm collection at the Date Palm and Iranian Tropical Fruits Institute in the city of Ahwaz. In the early days of the flowering season (March), the cultivars under study were identified and labeled. They were then checked on a daily basis and whenever the sheaths were ripe enough, they were picked and preserved in a sterile environment in room temperature. After the sheaths opened, the flower clusters were dried in the same environment and at the same temperature. Then, the cluster strings were separated and kept in a freezer at -18 °C until it was time for the test. Viability and vitality of the pollen was specified through the dying method using Acetocarmine solution.

The results showed that there was a significant difference among cultivars, temperature and interactions of them at the level of 1%. Among the studied temperatures, the highest germination of pollen grains in all cultivars occurred at 30 °C, followed by 33 °C and 27 °C, respectively, and the lowest germination percentage were obtained at 15 °C. Among cultivars, the percentage of pollen germination in ‘Ghanami Sorkh’ was quite high (92.45%), and ‘Nare Pakutah’ (87.33%), also, simultaneously ‘Sabz Parak’ (84.82%) and in the ‘Khareji’ cultivar was the lowest. However, the percentage of pollen germination in ‘Ghanami Sorkh’ cultivar was higher than 59% under a wide range of temperature from 21 to 39 °C. Furthermore, the percentage of Pollen germination was reduced rapidly at temperatures less than 21 Cº and reach 15.85% in 15 °C. The germination percentage of pollen grains in ‘Nare Pakutah’ cultivar in the temperature range of 21 to 39 degrees Celsius was higher than 57%. The germination percentage of pollen grains in ‘Sabz Parak’ cultivar decreased with less acceleration than ‘Ghanami Sorkh’ at lower and upper temperatures of 30 °C, so that at 36 and 39 °C had the highest amount of germination compared to the other cultivars. Also, the germination rate of pollens in ‘Ghanami Sorkh’ cultivar were investigated above 57% in the wide temperature range from 21 to 39 °C.

According to the findings of this study, the timing of pollination plays a crucial role in the fertility of male date palm cultivars, with the optimal temperature being around 30°C. It is essential to select cultivars that exhibit a high rate of pollen germination and contribute positively to fruit properties. Male cultivars such as 'Ghanami Sorkh', 'Sabz Parak', and 'Nare Pakutah' demonstrated a broader range of optimum temperatures for pollen germination. Therefore, these cultivars are recommended for climates characterized by significant temperature fluctuations during the flowering period of female date palms.

Date palm (Phoenix dactylifera L.) is one of the important crops in arid and semi-arid regions of the world. Today, plant tissue culture technology, as an important commercial method, provides the possibility of rapid reproduction of trees needed for the development of groves. Despite this, one of the main weaknesses of this method is the possibility of abnormal phenotypes such as delay in flowering, low levels of fruit set and formation of parthenocarp fruits. There is a difference between tissue culture date varieties in terms of the amount of abnormalities. In young tissue culture palm trees of Berhi cultivar, the amount of parthenocarp fruits reaches 59-86% and the yield of the date palm is greatly reduced. Therefore, identifying the causes of these abnormalities in tissue culture palms is very important.This study was conducted in order to investigate the changes in nutrient elements related to fruit setting in the pollination season on tissue culture derived date palms and derived from offshoot cv. Barhee in Date Palm and Tropical Fruit Research Center of Ahvaz city. At the beginning of spring season, palm trees were selected from each group of tissue culture and offshoot trees (10 years old). Sampling of flowers and fruits was done in the three stages of spath appearance, ripe spath and 2 weeks after pollination from three spathes. In the pollination stage, three spathes in each palm (1-2 days before natural opening) were pollinated with the same male pollen. Nitrogen, zinc, iron, magnesium, manganese, boron and potassium elements were measured in the flower or fruit samples collected from tissue culture and offshoot trees. In 5th week after pollination, fruit set percentage, parthenocarp fruits percentage and flower and fruit drop percentage were recorded. Also, cluster yield was measured at harvest time.The results showed that tissue culture derived plants had less fruit set (%) and more seedless fruits and drop (%) as compared to off shoot derived plants. Also, the fruit yield in the tissue culture plants was lower than off shoot derived plants. The levels of magnesium, manganese, boron, zinc and potassium in off shoot derived plants were higher than Tissue culture plants in most of the measured stages. By using multiple linear regression analysis and superior model selection, the amount of calcium and iron of flower and fruit had a negative relationship with the amount of fruit set and the amount of nitrogen, phosphorus, magnesium, manganese and boron had a positive relationship with it. The lack of nutritional elements in tissue culture plants in comparison to offshoot derived plants in different stages, especially pollination and fruit formation, may cause disturbances in the synthesis of carbohydrates, protein, and organic matter, so the growth and development of the plant and ultimately the amount reduce fruit yield. Therefore, optimal feeding of trees and foliar spraying with key elements such as boron, zinc, manganese and magnesium at different stages can be one of the effective ways to improve fruiting and achieve maximum yield and increase the quality of the fruit of these trees.

The purpose of this study is to investigate the chemical and microbial properties of date syrup during different stages of production line from the raw material to the final product. The amounts of total soluble solids, pH, acidity, total and reducing sugars, polyphenolic compounds, antioxidant activity and microbial count were measured and the type of microorganisms was determined based on phenotypic characteristics in different stages of production. The obtained results showed that during the stages of juice clarification and concentration, pH gradually decreased and acidity, total sugar, reducing sugar and total solid matter increased and reached their maximum in the syrup. Comparison of traditional syrup with factory produced syrup showed more pH and acidity, total and reducing sugar, total soluble solid, polyphenolic compounds and lower antioxidant activity for traditional syrup compared to the produced one. In general, the content of polyphenolic compounds and antioxidant activity gradually decreased in different stages of production, so that date syrup (279 mg of gallic acid per 100 grams of sample and 33%) indicated higher content of polyphenolic compounds and antioxidant activity than dates (388 mg of gallic acid per 100 g of sample and 57%). The results of the microbial test showed the lowest microbial load for the produced syrup compared to dates and different syrups. However, the presence of B. licheniformis in the syrup makes the product sour, in this regard finding a suitable solution to increase the shelf life of the product seems necessary. The traditional syrup showed a lower microbial load than the produced syrup, although B. licheniformis was observed in the traditional syrup despite the high heat treatment. Based on the obtained results, the date syrup was free of coliforms, which indicates maintaining the hygienic principles of manufacture during the production line.

Fusarium wilt disease is known as one of the most destructive and fatal diseases of date trees in many date-producing areas of the world, especially date-producing countries in Africa. Currently, a significant portion of date orchards in Morocco and the western and central Sahara of Algeria are affected by Fusarium wilt disease. The economic losses caused by Fusarium wilt disease of dates, especially in the incidence of severe epidemics, are significant. Over the past century, the disease has killed more than 12 million palm trees in Morocco and about three million palm trees in Algeria. Fusarium oxysporum (Schltdl.) f. sp. albedinis, a soil-borne vascular pathogen, is known to cause Fusarium wilt disease of dates. The economic losses caused by this disease are very significant, especially in the incidence of severe epidemics, and in some areas, the Fusarium wilt epidemic has destroyed more than 70% of the date fruits. Integrated disease management strategies include the use of resistant or tolerant cultivars, prevention of introduction of the disease causal agent into disease-free areas, eradication of the disease, biological control and chemical control. This disease has not been reported from date-producing areas of Iran, although similar symptoms to Fusarium wilt have been observed in some date orchards of Hormozgan province.

In this study, heat treatments (Temperatures of 50 oC, 60 oC and 70 oC for 1h & 2 h in 75-80% RH) and low temperatures (0 oC and -5 oC for 24 h and 48 h) were used in controlling of storage pests in Ghasb and Shamsaei date varieties. After treating and packaging, the date varieties were stored in cold room and also at ambient temperature for 6 months and the rate of pest infestation, microbial and chemical analysis were carried out after 2 interval months of storage. Oligonychus afrasiaticus and Ephestia figulliella were reported as important pests of Ghasb and Shamsaei dates in Shahdad region. Temperature of 70 oC for 2 h was the most effective for disinfestation and reduction of microbial load in Ghasb and Shamsaei date fruits. The rate of pest infestation and acidity (as lactic acid) in the samples of stored at ambient temperature increased during storage. The samples stored in cold room had not only the lowest rate of acidity and pest infestation but also the rate of infestation and acidity significantly reduced in these samples during storage. Cold room was effective in preventing the activity of microorganisms and pests in Ghasb and Shamsaei date varieties.

Nanotechnology, as a promising method for addressing sustainable agricultural issues, can increase propagation efficiency in palm tissue culture. The aim of this study was to prepare carbon nanoparticles and use the resulting nanocomposites to evaluate their efficiency in improving and increasing date callus formation.

Three separate experiments were performed to propagate calluses consisting of meristematic microsamples of dates. In the first experiment, calli prepared in MS culture medium were transferred to four culture media with different hormonal treatments from NAA and 2iP, and in the second experiment, calli composed of meristematic date microsamples in MS culture medium were transferred to four culture media with separate treatments from NAA and BAP. Different hormones were transferred from NAA and BAP. In the third experiment, after determining the best hormonal treatments from the first and second experiments, carbon nanoparticles were synthesized from graphite and calli composed of meristematic date microsomal samples were recreated in superior culture media with different concentrations of nanoparticles (0, 10, 20, 30, 40, 50 mg/L).

Based on the results of the first experiment, treatments of 10 mg / l NAA + 30 mg / l 2ip and 0.1 mg/l NAA + 0.05 mg/l 2ip were selected as the best callus propagation treatments. In the second experiment, it was found that there was no statistically significant difference between the applied treatments of 10 mg/l NAA + 30 mg/l BAP and 10 mg/l NAA + 10 mg/l BAP with other treatments with different concentrations of BAP. The results of the third experiment showed that the use of 10 mg/l NAA + 30 mg/l BAP + 30 mg/l CNP can produce the most calluses.

Due to the positive effect of carbon nanoparticles on increasing the weight of commodities, treatment of 10 mg / l NAA + 30 mg / l BAP + 30 mg / l CNP becomes the most suitable option for calorific cultivar propagation.

Dates is one of the most important horticultural products in Iran, which has a special place in food security, economy, and trade in agricultural products. Now, Iran is one of the biggest producers of dates in the world, but the lack of water resources is one of the main challenges in producing this crop in Iran. Therefore, the purpose of this study is to investigate the water footprint of date production in Iran using three specific waters, namely blue water, green water, and greywater. Then, using the concept of virtual water footprint introduced by Hoekstra and Hang (2003), the water trade footprint for the date crop was calculated for the years 2018-2001. The results show that the average annual harvest of water resources for date production in Iran is 3.486 billion m3, a total of 69.752 billion m3 of water was consumed between 2001 and 2018 to produce dates in Iran. 68% (2.352 billion m3 per year and a total of 426.466 billion m3) of the total need for date irrigation in Iran through abstraction from groundwater or so-called blue water, 28% (0.976 billion m3 per year, A total of 17.526 billion m3 has been supplied through green water and 4 % (0.139 billion m3 per year, a total of 2.764 billion m3) has been supplied through grey water. Examination of water footprint of date production showed that to produce 1 kg of dates in Iran,

Association of the plant with microorganisms such as dark septate endophytic fungi reduces the harmful effects of environmental stresses such as salinity. In this experiment, the effect of dark septate endophytes isolated from date palm roots on increasing salinity resistance of tomato (Lycopersicon esculentum cv. Super cheif) was investigated. The experiment was performed as a factorial in a completely randomized design with two factors including the type of isolate at 13 levels [4-B, 8-B, 10-D, 11-C, 14-A, 15-D, 16-A, 19-F, 21-A, 22-C, 22-E, 39-D, control (PDA plug)], and salinity at 3 levels (zero, 50 and 100 mM sodium chloride) with 3 replications. Tomato plants were inoculated with fungal isolates separated from date palm roots under salinity. Based on ANOVA results, in symbiosis with fungal isolates of 4-B and 11-C, the negative effects of salinity (up to 100 mM and equivalent to 9.52 dS/m) on tomato biomass were reduced. At salinity of 100 mM, 4-B had the highest plant fresh weight and 11-C had the highest plant dry weight compared to other treatments and were 55.51 and 26.55% higher than the non-inoculated treatments, respectively. By increasing the salinity level up to 100 mM, isolates of 4-B, 8-D, 10-D and 11-C had high efficiency in decreasing sodium concentration, increasing potassium concentration and potassium to sodium ratio. Symbiosis with some fungi (10-D and 8-B) caused a significant increase in phosphorus concentration (19%) compared to non-inoculated plants. At different salinity levels, isolates of 11-C, 39-D and 10-D increased the leaf relative water content. Increase in salinity up to 50 mM (equivalent to 5.44 dS/m) was associated with increased endophytic dependency and isolates of 11-C and 4-B showed the highest increase (43%) compared to other isolates.

Dust is one of the inevitable climatic features of Iran. Today, farmer’s most problem in the date regions is the effect of dust on date palm trees. This study carried out to investigate the effect of dust on Mazafati date fruit's chemical composition in three regions: Saravn, Jalq, and Routak in Sistan and Baluchistan province in 2016 and 2017. In each region five groves and in each grove, five palm trees with the same age (eight-year-old), height, number of reproductive years (third year of reproduction) were selected and marked for sampling the studied traits. Saravan region pollen was used to fertilize all trees. Some traits such as total soluble solids (TSS), total sugar content, pH, and also nutritional elements nitrogen, phosphorus and potassium were measured. Statistical analysis of the estimated traits was performed for two consecutive years based on the nested design. The result showed that the effect of the region (amount of dust) was significant for all traits. In Routak region with high dust content, total sugar was estimated to be 26.16% less than the Saravan region with low dust content. The percentage of nitrogen, phosphorus and potassium elements in Saravan region with low dust level was estimated 0.49, 0.68 and 1.48, respectively, and in Rotek region with high dust level was 0.32, 0.49 and 1.24, respectively. Since the three regions were different in terms of dust content, we can say that dust reduces the nutrients of Mazafati date fruit and reduces the quality and marketability.

AbstractIn many date palm gardens, different varieties of date fruits are commonly grown. Each of these varieties has different physical and chemical properties. Therefore, in the first step of developing intelligent sorting systems and quality monitoring systems, it is highly desirable to develop an automatic method for identifying the type of date fruit variety. This study aims to develop a classification algorithm of date fruit varieties using electronic responses from capacitive sensors and a force transducer. To simultaneously obtain the capacitive properties including the frequency and analog responses of date fruit and the force parameter related to the weight of the date fruit, an electronic platform was designed and constructed. In this platform, the capacitive responses and force parameters were provided by setting up the IC 555 and calibrating a 1 kg load cell. 120 date fruits from four different varieties, including Zahedi, Qhasb, Mazafati and Medjool were considered for the model development. A total of 30% of the samples were separated for final classification evaluation.  Decision Tree (DTs) as a non-parametric supervised learning method was chosen for classification. To tune, the classification model with the best hyper parameters fitting 3 folds for each of 2204 candidates, totaling 6612 fits were examined. The evaluation of the developed model resulted in a classification quality with F-scores of 64%, 50%, 100% and 100% for the four varieties Zahedi, Qhasb, Mazafati and Medjool. It was concluded that the developed capacitance base classification system can be successfully used to classify date fruit with acceptable quality.

Rice is one of the most important food items in the consumer basket of households and is one of the most widely consumed food products in Iran after wheat. Population growth, increasing consumption and demand, price fluctuations and welfare effects due to changes in the amount and price of rice require the attention, planning and foresight of policymakers and the country's planning system. In this study, the amounts of consumption and expenditure of urban households for the rice products (foreign rice grade 1 and grade 2 as well as four types of domestic rice) were estimated by seemingly unrelated regression equations (SURE) using related cross-sectional data in 2017 within the framework of inverse demand system and it was found that among the four reverse demand systems including IAIDS, IROT, INBR and ICBS, only Inverse Almost Ideal Demand System (IDIDS) was consistent with the research method data and preferred to the other three models, according to the results of Likelihood Ratio (LR) statistics. The study of substitution elasticity showed that the small number of substitution elasticitities between types of rice had little effect on the demand for one type of rice on the composition of other types of rice consumed. Other types of rice should be considered by planners in implementing protection and food security policies; and since rice is considered as an essential food for households, increasing the supply of this product to meet the demand growth in the future can be used as a favorable policy to increase consumer welfare.

The date is one of the most important export products in the Iranian agricultural sector. The significant share of dates in Iranian non-oil exports indicates the importance of the production and export of this product over the other agricultural products. Using numerical taxonomy approach, the present study aimed at investigating and determining the export pattern of Iranian dates based on market continuity indices, standard market continuity, average of price of date (US$), average import share of target country, coefficient of price fluctuation of date (US$), and coefficient of imported share of the target country fluctuation. The stugy results from prioritization of date exports to target countries indicated that the best export markets of Iranian Zahedi dates were Pakistan, Afghanistan, Kazakhstan, Kyrgyzstan and Turkey, the best export markets of Iranian Stameran dates were Australia, UAE, Canada, UK and Poland, the best export markets of Iranian Mazafati dates were India, UAE, Turkey, Pakistan and Azerbaijan, the best export markets of Iranian Kabkab dates were Russia, Kazakhstan, Ukraine, UAE and Iraq and the best export markets of Iranian Shahani dates were UAE and India. Considering the results of prioritization of the target countries in different tariff codes, it is recommended to take advantage of the preferential and bilateral agreements in the marketing of dates in the countries prioritized in each tariff code (presented in the results) so that the required conditions for export pattern change and access to the suggested pattern are provided.

Date palm is one of the most important trees in arid and tropical regions with very valuable fruit as a good food source. Therefore, the aim of this study was to investigate allelic diversity, the population structure and genetic diversity of important date palm genotypes using ISSR molecular marker for applying in genomic studies. 

Genomic DNA was extracted from leaf tissue of 68 date palm genotypes by Zhang method. The quantitative and qualitative evaluation of the extracted DNA was performed by using a spectrophotometer. For qualitative evaluation, DNA samples were visualized on 2% agarose gel. Polymerase chain reaction was performed using 10 ISSR primers. 

In this study, 74 polymorphic bands were created that showed an average of 65.78% polymorphism. Based on the results of this experiment, (AG)8YC', (TC)8C and (GA)8C are suitable markers in the study of genetic diversity of date palm. Structural analysis divided the study population into three sub-structures. The results of analysis of molecular variance between and within the three subpopulations showed that the share of variance within and between subpopulations was 79 and 21% of the total variance, respectively. The principle component analysis based on the Euclidean square distance matrix showed that the first ten components explained 54.57% of the total changes and diagram of the principal component analysis based on the first two principal components divided population into four groups. In addition, cluster analysis based on complete linkage clustering method and the Euclidean distance divided 68 date palm genotypes into four groups. 

The ISSR marker can be useful as a suitable marker for studying the differentiation and structure of the date palm population. High genetic diversity within and between subpopulations makes it possible to select parents for suitable traits in future breeding programs of date palm.

Due to the importance of date palm production in Iran, introduction of new cultivars, improvement of current cultivars and studying the genetic diversity among available cultivars is essential for improvement the quantity and quality of date palm production. In this research, 15 different local genotypes of date palm collected from Saravan, Jalgh, Nahook and Sinokan regions of Sistan and Baluchistan province were used for diversity analysis. To this end, DNA was extracted from leaves using Delaporta method and DNA quality and quantity were determined using spectrophotometer and 1% gel electrophoresis. PCR was performed using specific rbcL primers under determined conditions and the amplicons were sequenced. To study the relationships and genetic distances between genotypes, the results of sequencing were analyzed and dendrogram of phylogenetic relationships as well as sequence similarity matrix were generated using Bioedit, and MEGA7 software. The results of the present study showed that there were a total of 553 different residues for this marker of which 505 residues contained deletion and addition, and 48 residues were without deletion and addition. The genetic distance ranged from 0.0 to 0.037 and the highest intra-regional diversity was related to cultivar Jm13_sabzoo. Based on the dendrogram obtained from cluster analysis, the studied cultivars were divided into two branches, in which the first branch contained cultivar Sabzoo from Jalgh region and the other cultivars were grouped in different sub-branches of second branch. Although the rbcL marker is useful for studying and recognizing diversity of intraspecific relationships, a low genetic distance was estimated for the studied date palm genotypes. However, it is suggested that the other DNA barcodes as well the other appropriate molecular markers could be used for future studies of date palm genetic diversity.