This paper presents an analysis of technical efficiency andtechnology gap ratio (TGR) in greenhouse cucumber inFars Province, Iran. Cucumber production was chosen for thisstudy for the reason that greenhouse productions in this provincemainly have focused on this product. The data used in thisstudy was obtained from a random sample of 127 greenhouses in Fars Province for 2010 to 2011. Metafrontier productionfunction model for firms was used within the parametric frameworkof stochastic frontier analysis (SFA). The frontier modelsare applied in the analysis of cross-sectional data by assuminga translog functional form. Results indicate that eliminatingenergy input subsidies has led to significant decrease in greenhousecucumber production efficiency so that the mean technicalefficiency declined from 98% to 67 % during 2010-2011. Furthermore,subsidies elimination has also led to decrease of themean technology gap ratio in greenhouses from 0.92 to 0.87,in other words, it has caused more distance from efficient productionfrontier. Manuscript profile

Frequent droughts and their consequences result in the loss of groundwater, the deficiency of nutrients, the drying of surface water resources, and substantially more exploitation of the groundwater resources, which, altogether, cause the mobilization of saline waters to groundwater tables. This will impair the capacity of the aquifers and the quality of the water. The VIKOR method was applied to determine the best feasible solution according to the selected criteria including the local rainfall status in different years, soil permeability, land slope, and water quality indicators, including SAR, RSC, salinity for determination of groundwater resources quality and land-use restrictions in the Kashmar Plain in the northeast of Iran. The results of sampling performed on the Kashmar Plain showed that water quality was lost as one moved from the northern groundwater tables to the southern ones. The excessive use of groundwater resources, the downfall of the groundwater level, and subsequently, the increased salinity account for the loss of the agricultural water quality and the land-use restrictions. Furthermore, the results of the model within years 2010 and 2014 showed that if the current form of indiscriminate exploitation of groundwater resources is kept, it will lead to the mobilization of the salinity to the lowly-saline upstream regions. Therefore, it is necessary to focus on sustainable management of groundwater resources, control their indiscriminate exploitation, and minimize the damage to the groundwater tables in the study site. In addition, agronomists should work on limiting the use of agricultural land by modifying the cropping pattern and on using deficit-irrigation methods. Manuscript profile

A reason for the success of the agricultural sector in developed countries is the regulation of farm size as it allows for the scale economy of production. Considering that the size of agricultural production units should be specifically determined based on the crop and the area where it is produced, this study aims to determine the optimum size of rice farms in Fereydunkenar County, Mazandaran Province. So, 198 farmers were randomly interviewed in 2014. The results show that the optimal economic size of the farms in the study area is 1.949 ha, 43% larger than the average cultivation area in the region. The results of the technical efficiency using the Stochastic Nonparametric Envelopment of Data model (StoNED) also show that paddy size has a direct correlation with the efficiency of these units in the studied area and production in larger farms is more economical and efficient. Therefore, it is suggested to consider plans to encourage rice farmers to establish cooperatives and change their farm management style from small farm owning to integrated management. Manuscript profile