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Intermittent fires in Northeast Iran in the autumn of 2010 resulted in the burning of some valuable forest habitats. The objective of this study was to apply geographic information systems (GIS) to determine to what degree three key factors (environmental, climatic, and anthropogenic) influence the severity rating of fires in these forests. The forest fire sites were surveyed and imported into GIS. The severity of burnt areas was considered in relation to the three factors. Statistical functions were used to calculate the effect of the factors at each fire site. Logistic and stepwise regressions were used to determine the fire severity rating related to each factor. The results indicate that as the number of cumulative days after the onset of fire increased, the burnt areas also increased at a rate of 303.5 ha/day (R2 = 0.95). Consequently, forest density, daily mean wind speed, daily mean temperature and distance to roads were highly correlated with the daily severity rating of forest fires, and only daily temperature and forest density affected the size of the burnt areas. Prediction maps show that about 24% of the forests have high fire durability, amounting to 7% of the fire-sensitive area. The findings from this case indicate that GIS can be effectively employed in fire management to assess damage, and possibly to prevent future fires, thus assisting in the preservation of valuable forest resources. [ABSTRACT FROM AUTHOR]

Abstract: A simple model was constructed, tested and used to determine the potential yield of cumin (Cuminum cyminum). Using model outputs and data obtained from 228 fields, yield gap was determined. Yield gap varied considerably among regions (from 2.42 to 0.68 ton ha−1). Stepwise regression on data collected from fields showed that 73% of yield gap variation in 228 fields could be explained by fungal diseases (Fusarium oxysporum and Alternaria burnsii), inappropriate sowing dates and successive planting. Therefore, these were considered to be the main reducing factors in the studied regions, with 38% contributed by fungal diseases, 30% by sowing date and 5% by successive planting. When 67% of surveyed fields (averaged for all fields) were infected with these diseases and when there was a 3-mm increment in precipitation, infection increased about 1%. Our results indicated that 1% of the fungal infection increase equals to a yield loss of 150 kg per hectare. Sowing date of 63% of fields were also not within the appropriate range. Therefore, appropriate sowing date and all possible approaches to alleviate the effects of fungal diseases are the most fundamental advices to fill the gap between potential and actual yield of cumin in Khorasan provinces, Iran. Detailed descriptions of the model, important physiological parameters and other important state variables are also presented. [ABSTRACT FROM AUTHOR]

• Ideotype of 7 GM and non-GM rice cultivars assessed in north Iran. • Field experiments conducted in three isolated regions. • Iranian bio-safety standard protocol was followed. • Four GM cultivars had the cry1Ab gene in the vegetative stage. • Paddy yield in three regions was 1810.50-2377.6 kg ha−1. Using classical breeding, plant breeders envision a plant type whose yield they aim to enhance by selecting for individual traits to create model/ideal plants or ideotypes. To achieve this, those factors restricting yield need to be identified and controlled through the use of new technologies to achieve the desired ideotype. This study aimed to determine the ideotype of seven genetically modified (GM) and non-GM rice (Oryza sativa L.) cultivars. Field experiments were carried out in three isolated regions in the north of Iran under the Iranian bio-safety standard protocol. Four of the GM cultivars carried the cry1Ab gene in the vegetative stage while three non-GM cultivars served as the control. R2 values showed that five, six and seven variables in Sari, Amol and Rasht regions accounted for 63 %, 52 % and 74 % of paddy yield variation, respectively. In the same three regions, paddy yield variation due to white heads accounted for 28.38 %, 8.45 % and 3.95 % of the total variation in paddy yield, respectively. The total estimated variation in paddy yield in Sari, Amol and Rasht was 1810.50, 2377.6 and 2176.47 kg ha−1, respectively. Average data over the three regions indicated that highest loss in paddy yield was observed in non-GM 'Nemat', 'Khazar' and 'Tarom Hashemi'. GM cultivars derived from 'Khazar' showed significantly lower paddy yield loss than the non-GM parent. Dead heart, a condition that occurs in the vegetative stage in which the stem borer larva enters the stem and feeds on the growing shoot, causing the central shoot to dry, as well as white heads, which is a condition in which whole ear heads of adult plants become dry and yield chaffy grains, in all three regions were important variables contributing to paddy yield loss. In the future, producing GM rice resistant to striped stem borer with an active promoter in the reproductive growth stage might allow farmers to reduce a significant part of paddy yield loss resulting from white heads, which is directly negatively correlated with filled spikelets per panicle (R2 = -0.57**), in order to achieve an ideotype. [ABSTRACT FROM AUTHOR]

This study examined the impact of selenium (Se) (added as Na 2 SeO 4) and Se nanoparticles (N-Se), as a foliar spray, on several growth parameters, mineral content of leaves, yield, physical and biochemical characteristics of pomegranate (Punica granatum L. cv. Malase Saveh). The experiment was conducted over two consecutive years in the northwest of Iran. Se and N-Se were applied once in 2016 and once in 2017 at 1 and 2 μM (Se1 and Se2, N-Se1 and N-Se2, respectively), first at the full-bloom stage and then one month later. Control plants were sprayed with Se-free water. N-Se2 significantly increased the following parameters in the first year (2016) and second year (2017), respectively: leaf area (1.22- and 1.25-fold), chlorophyll content (1.34- and 1.24-fold), number of fruits/tree (1.35- and 1.28-fold), peel thickness (1.33- and 1.27-fold), fruit diameter (1.08- and 1.10-fold), and yield (1.17- and 1.16-fold). N-Se2 significantly increased N (1.23- and 1.22-fold), P (1.36- and 1.44-fold), K (1.08- and 1.11-fold), Ca (1.12- and 1.17-fold), Fe (1.15- and 1.18-fold) and Se (3.33- and 3.25-fold) content in leaves in both years while Zn content was higher after N-Se2 (1.03- and 1.07-fold) and Se1 (1.02- and 1.04-fold) treatments in both years. N-Se2 significantly increased, relative to the control and in the first and second year, respectively, total sugars (1.17- and 1.19-fold), the content of phenolic compounds (1.05- and 1.08-fold), antioxidants (1.23- and 1.25-fold), and anthocyanins (1.23- and 1.27-fold). Se and N-Se treatments enhanced maturity index and decreased fruit cracking. Broadly, our results indicate that a high concentration of N-Se has a greater and more beneficial impact than a low concentration. Future experiments should focus on increasing the concentration of N-Se. These findings can assist in pomegranate fruit production in arid regions. • Se and nano-Se (1 and 2 μM) were applied to pomegranate at two stages of the life cycle. • Nano-Se at 2 μM significantly increased leaf area and chlorophyll content. • Number of fruits/tree, peel thickness, fruit diameter, and yield also increased. • N, P, K, Ca, Fe and Zn in leaves in both years increased in response to 2 μM nano-Se. • Se (1 μM) or nano-Se (2 μM) improved pomegranate growth and quality. [ABSTRACT FROM AUTHOR]