امیر بهزاد بذرگر

Sugar beet is an industrial and strategic crop regarding sugar production in Iran, however, accurate information on its yield potential (Yp) and yield gap (Yg) is limited. The aim of this study was to estimate the yield potential of sugar beet using GYGA protocol according to the current conditions for the first time in Iran. Based on this protocol, agro-climatic zones (CZ), reference weather stations (RWs) and buffers within each meteorological station in each climatic zone as well as the type of soil texture in the buffer range were determined and yield potential, yield gap and production were evaluated using SSM-iCrop2 model. Finally, 28 weather stations were selected for sugar beet in 13 climatic zones which cover 92.7% of total sugar beet cultivation areas. The modeling results estimated the yield potential and yield gap to be 11.39 and 6.23 M t, respectively. Actual yield and the yield potential were 46.663 and 102.986 tha-1, respectively resulting in yield gap of 56.323 t ha-1 for sugar beet production in Iran with a relative yield (RY) of 45%. This indicates that current management practices produce only less than half of the performance potential.

Energy flow is one of the most important issues in agroecology. The amount of energy that is consumed in different agroecosystems not only depends on the type of crop but also on the material and methods that is used in its production. Potato plants are one of the most important crops that is produced in Torbat Heidarieh region, Khorasan Razavi Province of Iran. Different irrigation methods influence the energy consumption and production. Thus, the aim of this study is to compare energy efficiency of potato with different irrigation methods.

In order to evaluate and compare the efficiency of energy consumption in potato production based furrow,  sprinkle and drip irrigation methods, a study was carried out at 11 fields in the Jolgeh Rokh Torbat Heidarieh region in 2013- 2014 . The comparison was performed using a completel randomized, unbalanced design. In which the type of irrigation system was considered as the treatment and fields that were matched to each irrigation system as a replication. The studied traits included the amount of input and output energy, the equivalent energy of all inputs, and energy use efficiency, net energy, energy production and specific energy.                                                                                                                                         

The largest amount of energy consumed by the human labor was due to furrow irrigation. The highest average of fossil fuel consumption was due to furrow irrigation method followed by sprinkle and drip irrigation. The amount of electricity consumed in the drip irrigation method had the highest amount compared to the other two methods. The most energy consumed by nitrogen fertilizers was related to furrow irrigation method, and the methods of irrigation of droplets and sprinklers in this regard were ranked in the following order, respectively. The amount of energy consumed by phosphorus fertilizers in irrigation was the least amount of droplets. This amount was in sprinkler irrigation and furrow irrigation respectively, although there was no significant difference between the two methods. The energy of using potassium fertilizers in the highest irrigation system was similar to the other irrigation systems. The energy consumption of herbicides was highest in drip methods and furrow irrigation was in the next category. Energy consumption of machinery was highest in sprinkler irrigation method. In the recent method, energy consumption of machinery was about half of the energy consumption of the total inputs. Indirect energy consumption for drip irrigation system was 6868 MJ.ha-1 and in sprinkle irrigation 2756 MJ.ha-1. Energy produced by seed was highest in drip irrigation method and the lowest in sprinkle irrigation. The total amount of input and output energy in sprinkler irrigation method was the highest (106674.24 and 162000 MJ.ha-1), followed by drip irrigation (97807.82 and 151000 MJ.ha-1) and furrow irrigation (92539.61 and 139000 MJ.ha-1) were placed in the following categories. The energy use efficiency of the drip irrigation method 1.6 was more than other irrigation methods. Production energy in terms of amount of drip and furrow irrigation was the highest 0.44 and in sprinkle irrigation 0.41. Net energy was the highest in sprinkler irrigation (53392.18 MJ.ha-1) and the lowest in furrow irrigation (46660.38 MJ.ha-1). Production energy was highest in drip and furrow irrigation (0.44 and 0.43) and lowest in sprinkle irrigation (0.41). The specific energy in furrow irrigation (2.36) was higher than the other methods and in the drip irrigation with the lowest (2.32).                                                                               

According to the results of the present research, in spite of higher yield of potatoes under sprinkle and drip irrigation systems, there were not significant differences among the energy indices; energy efficiency, energy productivity, and special energy; of three systems. This was due to more total input energy in the sprinkle and drip systems. Because the machinery and installations energy input in furrow irrigation system were lower than two other systems.

Life Cycle Assessment (LCA) is a method that evaluates all environmental effects of a product during its life cycle. The objective of this study was to introduce LCA to Iranian scientific community and to use it in assessment of environmental impact of different production systems of sugar beet in former Khorasan province, west of Iran, compared to Swiss condition. The data were gathered regarding materials and processes from traditional, semi-mechanized and mechanized production systems in 26 regions of 11 geographic areas of Khorasan (current North, Razavi and South Khorasan provinces), the inventory analysis. Then, all the resources (inputs) and environmental emissions (outputs) were quantified under environmental impact category. The results indicated that there is a significant gap between Khorasan and Swiss (optimum situation) in terms of environmental impacts per each ton of sugar beet production (up to 40 times in some of environmental impact category). Moreover this study demonstrated that mechanized sugar beet production system is more environmental friendly regarding to depletion of non-renewable energy sources, global warming, eutrophication, photochemical oxidation, acidification, land use and ozone layer depletion among various systems of sugar beet production in Khorasan. Contribution analysis indicated that irrigation had the greatest role in creating environmental impacts. Climatic condition of this region and the existence of drought led to spend a lot of energy for irrigation. Providing this energy causes high environmental impacts due to the dependence on fossil fuels.

Nitrogen is one of the most important nutrients in crop production, but it's losses to the environment is harmful. The SUNDIAL model (simulation model of N dynamics in the soil) was used to quantify the cycle of N and it's losses in different production systems of sugar beet (Beta Vulgaris L.) in former Khorasan province, east of Iran. The data were collected from traditional, semi-mechanized and mechanized production systems in 26 regions of 10 geographic areas of Khorasan (Northern, Razavi and Southern Khorasan provinces) to be used in the model as inputs. Results showed that the total N loss from the soil profile in traditional, semi-mechanized and mechanized systems did not differ significantly and were 50, 41 and 45 kg N ha-1, respectively. In average, 59% of total N loss occurs as gaseous losses and 41% as leaching. The most part of the gaseous losses in traditional system occurs via denitrification (63%), but in semi-mechanized (75%) and mechanized (82%) systems volatilization was dominant. The key finding is that while various systems of sugar beet production are similar with respect to N loss per hectare, they are different with respect to N loss per ton of crop yield. The average of N loss in traditional system was significantly more than other systems in terms of kg N ton-1. This implies the possibility of reducing N losses and its environmental effects thorough improving crop management.

The environmental impact quotient (EIQ) developed by Kovach et al (1992) is used an effort to fill an important gap; i.e. the need to provide farmers and others with easy-to-use information about the adverse effects of pesticides. It represents a method for calculating the environmental impacts of pesticides, and the values obtained from these calculations can be used to compare different pesticides and pest management programs with each other to ultimately determine which program or pesticide is likely to have the lowest environmental impact. The EIQ value for a particular active ingredient is calculated according to a formula that includes parameters for toxicity (dermal, chronic, bird, bee, fish, and beneficial arthropod), soil half-life, systemicity, leaching potential, and plant surface half-life. Each of these parameters is given a rating of 1, 3 or 5 to reflect its potential of causing harm. Six of these ratings are based on measured or known properties and the other five are based on judgments according to their potentially low, moderate or severe impact. Since the EIQ value is mainly a hazard indicator, additional calculations are required to obtain an indication of the pesticide risk. To account for exposure, an equation called the Field Use EIQ has been developed. This rating is calculated by multiplying the EIQ value for a specific chemical from the tables by the percent active ingredient in the formulation and its dosage rate used per hectare (usually in liters or kilograms of the formulated product). EIQ is used in different studies to compare the environmental effects of different pesticides and/or different production systems (Avila et al., 2011; Doris et al., 2011; Gallivan et al., 2001; Macharia et al., 2009). The aim of this study was to evaluate management strategies in using pesticides in wheat and barley farms in the city of Mashhad located in the Khorasan Razavi province in Iran.

Data related to pesticides (insecticides, herbicides and fungicides) used in wheat and barley in the city of Mashhad located in the Khorasan Razavi province were gathered through face to face filling questionnaires by the users. The indices measured in this study include Environmental Impact Quotient (EIQ) and its components (farm worker, consumer, leaching and ecology) and Field Use Rate - EIQ (FUR-EIQ). EIQ is calculated based on the work of Kovach et al. (1992). The formula is: EIQ={C[(DT×5)+(DT×P)]+[(C×((S+P)/2)×SY)+(L)]+[(F×R)+(D×((S+P)/2)×3)+(Z×P×3)+(B×P×5)]}/3 In this formula: DT: Dermal Toxicity; C: long term health effects; SY: mode of action; F: fish toxicity; L: leaching potential; R: surface runoff potential; D: bird toxicity; S: soil residue half-life; Z: bee toxicity; B: beneficial arthropod toxicity; P: plant surface half-life. EIQ field use rating was calculated by multiplying the EIQ value for a specific chemical from the table by the percent active ingredient in the formulation and the rate of its dosage used per hectare: EIQ Field Use Rating = EIQ × % active ingredient × Rate

A large degree of variation was observed in the amount of EIQ and its components. The results showed that in wheat cultivation, Carbendazim had the most effect on the farm worker component and Diazinon had the least effect on this component. The most risk of the consumer and leaching component in wheat fields were shown in fungicides. The fungicide Carbendazim had the most effect on the consumer and leaching component. The least effect on consumer and leaching component were obtained in Deltamethrin. Replacement of Carbendazim with Iprodione, Thiram and Carboxin which are used for disinfection of seeds will improve the consumer and leaching component. In terms of ecology, the Diazinon component had the most dangerous environmental risk in wheat fields. In this section, pesticides were more importance than fungicides. The use of Deltamethrin to control Eurygaster integriceps in wheat, is not recommended and it should be replaced by Trichlorfon because of the risk of ecological destruction. Such ecological destruction is not much different among the various fungicides. The maximum and minimum amount of EIQ among the pesticides used in wheat farms in Mashhad were obtained in Diazinon and Deltamethrin, respectively. 2, 4- D and Fenoxaprop ethyl had the lowest and highest EIQ indices among the herbicides used in wheat farms. The lowest FUR-EIQ index in wheat fields was observed for the application of herbicides. The maximum value of this index was shown in the usage of fungicides. The highest value of the EIQ-FUR related to the Carbendazim fungicide. Due to low consumption of Detamethrin, it had the small value of this index. Considering EIQ-FUR, the use of Deltamethrin is considered to be more appropriate than Trichlorfon. Use of Iprdion for the disinfection of seeds, and Tribenuron-methyl for the elimination of weeds in wheat fields are the best choices since they had the lowest FUR-EIQ index. In barley cultivation, Carbendazim and Diazinon had the most and the least effects on farm worker component, respectively. In the consumer and leaching component, the most and the least effects were to the observed in Carbendazim as a fungicide and in the Deltamethrin as an insecticide, respectively. In terms of ecology, the Diazinon and Tribenuron-methyl components had the most and the least effect respectively. In this respect, the fungicides used for seed treatment did not show much difference. The maximum EIQ among the pesticides used in barley fields in Mashhad was observed in Carbendazim. Iprdion used for the disinfection of seeds had the lowest EIQ. Considering the herbicides 2, 4- D and Fenoxaprop ethyl had the lowest and highest values of EIQ, respectively. The evaluation of FUR-EIQ in barley fields in Mashhad showed that cyproconazole was the best fungicide used for seed disinfection and it is a good alternative for Carbendazim. Carbendazim was assessed as the most dangerous environmental pesticide. Considering the pesticides dosage and FUR-EIQ, Deltamethrin was found to be a suitable insecticide against Eurygaster integriceps and Tribenuron-methyl was found to be a less dangerous herbicide. The results showed that in wheat and barley farms in Mashhad, the biggest danger in farm worker consumer and leaching components was Carbendazim fungicide. Diazinon pesticide had the lowest risk in the farm laborer component. The lowest risk in consumer and leaching component related to the Deltamethrin pesticide. In terms of the ecology components, the most environmental degradation was created by the Diazinon pesticide. Carbendazim is the most dangerous pesticide. Based on the measurements of FUR-EIQ, the fungicides had the highest risk and the herbicides had the lowest risk.

Environmental optimizing of pest management strategies and improving theirs trends towards minimum environmental risks programs is a matter of considerable concern of food scientists particularly in developing countries. This study evaluates the environmental impacts of pesticides consumption based on Environmental Impact Quotient (EIQ) model in different sugar beet (Beta vulgaris L.) production systems in Khorasan provinces as the largest producer of this strategic crop in Iran. For this purpose, information of pesticides used in 26 locations of 11 geographic regions in Khorasan provinces, (North, Razavi and South Khorasan provinces) in three types of production systems was gathered: mechanized, semi-mechanized and traditional. In all three production systems, based on EIQ index which uses three risk components: farm worker, consumer and leaching and environment to estimate the relative potential risk of pesticide, the most negative effect of pesticide consumption was on ecosystem organisms as ecological component. Results showed that there is no relationship between sugar beet yield and increasing both diversity of pesticides types and quantity of active ingredients consumption as well. Moreover, granted that increasing in mechanization in sugar beet production caused more environmental load in farm, considering sugar beet yield, mechanized systems resulted in 33% less environmental damage per 1 ton sugar beet produced. Thus, it is expected that there is a possibility to improve ecological function of Khorasan sugar beet production systems without economic loss by substitution or decreasing the use of pesticides. Also, employing more mechanized and more productive systems may reduce environmental hazards in national scale and decrease environmental load due to transportation of non local production in international scale.