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In this study, the energy, exergy and yield is calculated for two cultivars of quinoa (Sajama and Titicaca) production. The result shows that the energy consumption, exergy consumption, energy efficiency, and exergy efficiency for producing quinoa are calculated to be 10,932.34 MJ/ton, 14,6940 MJ/ton, 141.32% and 15.9% in Sajama cultivar and 6,442.42 MJ/ton, 98,243.6 MJ/ton, 215.3% and 20.6% in Titicaca cultivar, respectively. The grain yield of Titicaca cultivar is higher, although its growth duration is less as compared to Sajama cultivar. The combined application of bio-fertilizer with chemical fertilizers give the highest growth duration, grain yield, 1000-seed weight, biological yield and harvest index, when compared with the sole application of fertilizer and no fertilizer. Nitrogen fertilizer consumes the highest amount of total energy inputs followed by irrigation water and diesel fuel for quinoa production. About 97.5% of total input exergy consumed in quinoa production is water irrigation. Thus, it is clear that decrease in the use of irrigation water decreases the environmental impact and increases sustainability and vice versa. In pursuit of sustainable agriculture goals, Titicaca cultivar could be introduced as advanced cultivar in saline and drought stressed fields as a crop with high potential yield and nutritional value.

In order to investigate the effects of solitary and combined application of chemical and biological fertilizers on the yield and yield components of quinoa plant, a factorial experiment was conducted based on randomized complete block design with three replications in Dastgerd (Borkhar), Isfahan, central Iran, during the 2017-2018 growing season. Experimental factors included four levels of Chemical fertilizers [control, urea, triple superphosphate (TSP), and combined urea + TSP fertilizers] and bio-fertilizers at four levels (no inoculation, and inoculations with nitroxin, bio-phosphorus, and combined nitroxin + biophosphorus). Results showed that the interaction effects of chemical and biological fertilizers on leaf area index, grain yield, and yield components (including number of panicles per m2, number of grains per panicle, and 1000-grain weight) of quinoa plant were significant at 1% probability level. Combined application of urea and TSP fertilizers had the highest impact on the biological yield. Overall, the results showed that plant height, chlorophyll content and the number of panicles per m2 were significantly influenced by nitrogen sources of fertilizers used in this study. The phosphorus fertilizer sources had the highest effects on leaf area index, number of grains per panicle, 1000-grain weight, grain yield, and biological yield, which can be attributed to the greater impact of nitrogen on the increase of prolific panicles and to the marked role of phosphorus in both flower and grain formation. The integrated application of biofertilizers and all of the examined chemical fertilizers treatments increased the yield of quinoa plant compared to the control. Therefore, the application of biofertilizers as supplements can be introduced as a practical approach for optimal and balanced use of chemical fertilizers in order to achieve sustainable agriculture goals in quinoa cultivation.

A field study on sugar beet with foliar application of jasmonic acid (JA) was evaluated under deficit irrigation regimes. The experiment was carried out in randomized complete block design with three replicates at two locations (Shahrekord and Shalamzar) in Chaharmahal-Bakhtiari Province, Iran during 2015 growing season. The experiment applied JA on sugar beet (Beta vulgaris L.) at two different concentrations of 5, 10 µM and control (foliar with water) under three water requirement of sugar beet (100, 75 and 50%). Physiological parameters of the sugar beet such as proline, soluble carbohydrates, chlorophyll content, carotenoid, anthocyanin, membrane stability index, root sugar content, root yield and sugar yield were evaluated. The results revealed water deficit led to decreases in carotenoid, chlorophyll content, relative water content, membrane stability index, root yield and sugar yield while proline and root sugar content increased significantly. Foliar application of JA resulted in notable improvements in the mean of all traits. JA amendment positively affected plant water relations mostly due to enhancements in osmoregulation. Ameliorative effects of exogenous JA tended to be greater in drought-stressed sugar beet plants as it led to the enhancement of chlorophyll content and relative water content in water deficit conditions. The results in this study demonstrated that the foliar application of JA significantly mitigated detrimental effects of water stress in sugar beet with increased root sugar content and sugar yield under water deficit regimes.

In order to study the effect of phosphate biofertilizer and chemical fertilizers of nitrogen, phosphorus and sulfur on some growth and yield components of Camelina sativa L., a study was conducted based on a factorial experiment; this was done in a randomized complete block design with three replications at Kazeroon during the 2016 growing season. Treatments included bio-based phosphorus (P) fertilizers (Barvar-2) containing phosphate solubilizing bacteria (PSB) (the Pseudomonas putida Strain 13P and Strain 5P and the Pantoea agglomerans Strain 5P) as the first factor at two levels (inoculated and uninoculated seeds) and chemical fertilizer as the second factor, including control, nitrogen, phosphorus and sulfur alone, based on the recommended doses of NPS and 50% recommended NPS fertilizers. The results showed that the effect of the use of the biofertilizer on plant height and number of seeds per silique and the number of siliques per plant, 1000 seed weight and harvest index were significant, but the number of branches, grain yield and biological yield were not significant. The use of chemical fertilizer as well as the interaction of chemical fertilizers × phosphate biofertilizer on all traits was significant. The combined use of bio-inoculants and chemical nitrogen + phosphorus + sulfur fertilizer, as compared to the control, increased plant height by 50.58%, the number of branches by 26.7%, seed number per silique by 29.8%, the grain yield by 86.88%, biologic yield by 63.58%, and harvest index by 32.36%. Nitrogen consumption increased the number of siliques per plant by 27.84% and nitrogen + sulfur treatment imrpoved 1000 seed weight by 54.54%, relative to the control treatment. So, according to the results of this experiment; the best fertilizer treatment for Camelina sativa L. production was the combination of nitrogen + phosphorus + sulfur fertilizer plus biofertilizer application.

Arbuscular mycorrhizas (AMs), formed between AM fungi and vascular plants, are a widespread mutualistic symbiosis where fungi colonize root cells, transfer mineral nutrients (mainly phosphate) and, in turn, obtain carbon of a photosynthetic origin. To explore the possible roles played by antioxidant enzymes in the roots and shoots of AM-inoculated potato cultivars, a field experiment was conducted using three potato cultivars (Agria, Sante and Arinda) and two Glomus intraradices levels (0 and 30 g). The leaf and root activities of catalase (CAT), peroxidase (POX) and ascorbate peroxidase (APX) affecting mycorrhizal colonization and potato yield were measured. Under AM inoculation, the three CAT, POX and APX enzymes were induced in both the roots and leaves of all the cultivars. However, the highest increases in POX, APX and CAT activities under AM inoculation were noted in the leaves of Sante and the roots of Arinda. Mycorrhizal colonization was more pronounced under arbuscular mycorrhiza inoculation compared with the control. Yield also increased by 36%, 26% and 20% in Ardina, Sante and Agria, respectively, when they were inoculated with arbuscular mycorrhizas. The results suggest that inoculation of potato cultivars with AM induces antioxidant enzymes and, thereby, higher yields. In addition, induction of enzymes is found to be cultivar-plant-part specific.

Two common bean genotypes were subjected to non-drought stress (NDS), moderate drought stress (MDS), and severe drought stress (SDS). This field experiment was carried out as split plot wit...

In order to evaluate the effect of different fertilizers’ sources on micronutrients’ content and sugar quality of sugar beet, three fertilizers’ sources include spent mushroom compost (SMC)...

About 90% of Iran extends over arid and semi-arid areas where drought stress is inevitably suffered by crops such as common bean. Due to limitations in water resources and importance of common bean in Iran, it is essential to evaluate common bean under water-deficit condition. The objective of this study was to determine effects of deficit irrigation on the yield, physiology and biochemistry of two bean genotypes. Experiments were conducted at the Agricultural Experimental Station, Shahr-e-Kord University, Shahr-e-Kord, Iran during 2014 and 2015. The plants were submitted to non-drought stress (NDS), moderate drought stress (MDS) and severe drought stress (SDS) under field conditions. Seed yield, phenological stages, leaf greenness, relative water content (RWC), stomatal conductance (SC), canopy temperature depression(CTD), intercepted PAR (PARi), leaf area index(LAI), radiation use efficiency(RUE), lipid peroxidation, activity of enzymatic antioxidants, water use efficiency(WUE) and water productivity(WP) were recorded. The results indicated that, seed yield decreased due to deficit irrigation; RWC, SC and leaf greenness were lower under MDS and SDS conditions; whereas deficit irrigation had not equal effects on WUE, WP and RUE of the tested genotypes. Under NDS condition, genotype KS21193 is superior than genotype KS21486 in many traits including seed yield, RUE, PARi, WUE and WP. While, the situation is changed under water deficit conditions, so that KS21486 is superior than KS21193 in terms of the majority of traits measured such as seed yield, RWC, RUE, SC and CTD before irrigation, WUE, WP. In fact, genotype KS21486 is more tolerant to water deficit conditions than another genotype. This was attributed to various mechanisms such as stress escape, decreased chlorophyll, LAI and PARi, more conversion efficiency of received water and PAR into dry matter and economic yield and more efficient enzymatic antioxidants.

In order to evaluate the suitability of maize hybrids in different planting dates, an experiment was conducted as split plot in JalilAbad, Varamin, Iran in 2015. Main and sub plots were planting date (D1: April 4, D2: April 19, D3: May 5, D4: May 20) and maize hybrids (H1: Gazda, H2: Maxima, H3: KSC 701, H4: AS160) respectively. Results indicated that there was variation between hybrids in terms of leaf area index (LAI), dry matter, crop growth rate (CGR), relative growth rate (RGR) and net assimilation rate (NAR) in different planting dates. Also results showed that the effects of planting date, hybrid and planting date × hybrid interaction on plant height, plant weight, ear weight, ear/plant weight ratio, silage yield and water use efficiency were significant. Among the qualitative traits examined, the effects of hybrid on protein and neutral detergent soluble fiber were significant. The best planting date for achieving the highest silage yield of hybrids Maxima and AS160 were May 5 and 20, but for KSC 701 was April 19 and May 5. However hybrid Gazda had a similar yield in all planting dates. It was concluded that even though cultivation of KSC701 and Maxima seems preferable in terms of silage yield but repeating this experiment in further years is necessary for a solid recommendation.

This study was conducted to simulate the climate change impacts on potato production and evaluate the planting date and variety management as possible climate change adaptation strategies in Isfahan province, Iran. Two types of General Circulation Models (HadCM3 and IPCM4) and three scenarios (A1B, A2 and B1) were employed. Daily climatic parameters were generated by Long Ashton Research Station-Weather Generator (LARS − WG). The SUBSTOR-Potato model was used to simulate the baseline and future potato growth and development. Results indicated that LARS-WG and SUBSTOR-Potato had an appropriate accuracy to simulate climatic and growth parameters of potato. Simulated results showed that the maximum leaf area index (LAI), days to tuber initiation (DTTI), days to harvest (DTH) and fresh tuber yield of evaluated variety will be declined as affected by future climate change. Based on the simulation results, delayed planting date (31 May) would increase tuber yield under future climatic conditions. In the contrary, early planting (30 April) would accelerate harmful effects of climate change on potato yield. The medium and early maturing varieties showed a better tuber yield under climate change conditions than common (delayed maturing) variety. In essence, early maturing variety and delayed planting date are reported as the most efficient agronomical approaches for mitigating harmful effects of climate change and proposed to be considered in designing and managing potato ecosystems of the region for future climatic conditions. Generally, our results highlight the importance of considering early maturing variety and delayed planting date as the efficient agronomical approaches for mitigating harmful effects of climate change on potato production.

Drought stress (DS) is a major concern in the agricultural sector and, in particular, for sugar beet production and sugar content. As such several agricultural practices have been used to minimize yield losses from DS, and foliar application of proline is considered one such approach to improve drought tolerance in growing plants. Hence, the current study examined the proline-related improvements to induce drought tolerance in sugar beet plants. A field experiment was conducted at two locations (Shahrekord and Shalamzar) in Chaharmahal-Bakhtiari province, Iran. Experimental treatments comprised of three DS levels (well water: 100%; mild stress: 75%; severe stress: 50% water requirement of plant), and three proline applications (control: 0; low: 5 mM; high: 10 mM). DS caused a significant up-regulation in leaf proline content, malondialdehyde (MDA) content, hydrogen peroxide (H2O2) content, ascorbate peroxidase, catalase, and peroxidase enzymatic activities. This increase was more pronounced under proline application with concomitant down-regulation of MDA and H2O2 contents. DS also caused a decrease in leaf photosynthetic pigments, leaf relative water contents, membrane stability index and sugar beet root production; however, proline application mitigated these adverse DS effects. The study results suggest beneficial effects of proline applications, which is crucial to mitigation of the detrimental effects of DS in sugar beet by enhancing antioxidant enzymatic activities with concomitant reduction in MDA and H2O2 contents.

Sugar beet (Beta vulgaris L.), accounting for 30 percent of the total world sugar production, maybe affected by drought in terms of both its yield and quality. Proline is an amino acid with pivotal role in plant responses to drought stress. The present experiment was conducted at two locations during 2015. The treatments included 100 %, 75 %, and 50 % irrigation water requirements (IWR) and 0, 5, and 10 mM of proline. Drought stress reduced root diameter and length, K content, alkalinity coefficient, molasses content, root yield, and white sugar and sugar yields, but increased leaf and root proline content, Na, α-N, and sugar and white sugar contents. However, proline application improved yield and food quality of sugar beet and 10 mM proline was more effective. Sugar and white sugar yields increased by 18 % and 15 % by 10 mM proline respectively. Combination of 50 % IWR and 10 mM proline application increased root yield by 26 % as compared to drought stress alone. The results showed that proline is the most sensitive osmoticum in sugar beet’s response to water stress and improvement in water relations and osmoregulatory measure in yield and quality of sugar beet.

Hemp is one of the industrial plants so that its oil is extracted from its grains and its quality and quantity are affected by abiotic stresses, especially water deficit. In order to study the physiological and biochemical responses of hemp to drought stress and zeolite application, a two-year experiment was performed in the experimental field of Shahrekord University (Shahrekord, Iran). Four levels of irrigation including severe stress, moderate stress, mild stress and well-watered (40 %, 60 %, 80 % and 100 % of crop water requirement, respectively) and 3 rates of zeolite clinoptilolite application including 0, 5 and 10 t ha−1 during growth season in 2014 and 2015 were studied as split plot. Water deficit reduced the morphological characteristics, chlorophyll content, dry matter and oil yield, and increased carotenoids content, antioxidant enzymes and oil content. The percentage of dry matter and oil yield reduction was improved with zeolite application, and the lowest percentage of dry matter and oil yield reduction compared to control was obtained from 10 t ha−1 zeolite under mild stress. Zeolite also greatly kept the process of antioxidant enzymes close to suitable conditions and reduced their activity, especially under mild stress. Thus, zeolite application reduced the negative impact of water deficit on these traits in hemp. It seems that 10 t ha−1 zeolite under mild stress conditions increases the threshold of hemp perception of water deficit and the activity of its defense systems has been reduced dramatically.

Quantitative knowledge of the cardinal temperatures, optimal sowing depth, and soil bulk density ( ρ b ) required for germination and emergence of flax (Linum usitatissimum L.) and sesame (Sesamum indicum L.) is scarce. An experiment was conducted across eight temperature treatments to determine the cardinal temperature and physiological time (hour number under optimum temperature) required for germination (using beta, dent-like and segmented models). Another experiment was performed for quantifying the emergence response of flax and sesame to ρ b (1, 1.1, 1.4, 1.7 g.cm−3) and sowing depth (1, 2, 3, 4 cm). The results revealed that the responses of flax and sesame germination to temperature were best explained by a dent-like model. Base temperature ( T b ), lower optimum ( T o 1 ), upper optimum ( T o 2 ), and ceiling temperatures ( T c ) of flax were estimated at 9.1, 20.2, 27.3 and 40.3 °C respectively. Further, the sesame T b , T o 1 , T o 2 and T c was 13.6, 34.2, 38.2 and 41.8 °C respectively. The physiological time to 50% germination was 32.7 h in flax and 12.4 h in sesame. Best sowing depth and soil bulk density for sesame was 1–2 cm and 1–1.4 g cm-3, respectively. However, flax showed less sensitivity (to ρ b and sowing depth) and emergence rate was reduced only in deeper sowing (4 cm). This results help understanding the biology of these crops and it provides data for developing future field emergence models to optimize the timing of crop sowing.

Plant availability of potassium (K) in soils is controlled by dynamic interactions among its different pools. Potassium quantity–intensity (Q/I) parameters were determined to relate them to bean plant indices in a pot experiment. The results showed that the activity ratio at equilibrium (ARk) ranged from 0.015 to 0.358 (mmol L−1)0.50, the potential buffering capacity (PBC) ranged from 7.54 to 26.32 mmol kg−1/(mmol L−1)0.50, the labile K (Δk°) ranged from 9.1 to 112.2 mg kg−1, and the K adsorbed at specific sites (Kx) ranged from 6.51 to 69.69 mg kg−1. The results of pot experiment showed that some K Q/I parameters were significantly correlated with some plant indices. Also, the correlation study showed that readily exchangeable K was significantly correlated with K Q/I parameters except Kx. The results of this research show that the K Q/I method can be used for estimating of soil K availability for bean.

Today, the world community is looking for fuel efficient and environmentally viable alternatives for many of the traditional energy conversion approaches. This development has further worked to increase the technical focus on conventional cycles for making them more optimum in terms of performance. Hence, the objective of this paper is to study the effect of ethanol-air equivalence ratio on the power output and the indicated thermal efficiency of an air standard Otto cycle. Optimization of the cycle has been performed for power output as well as for thermal efficiency with respect to compression ratio. The results show that the maximum power output, the optimal compression ratio corresponding to maximum power output point, the optimal compression ratio corresponding to maximum thermal efficiency point and the working range of the cycle first increase and then decrease as the equivalence ratio increases. The result obtained herein provides a guide to the performance evaluation and improvement for practical Otto engines.