Crop Production
Year:2014 | Volume:7 | Issue:1|Papers Count:11

Application of appropriate agricultural operations is a strategy to reduce energy consumption and greenhouse gas emissions from agricultural productions process. In this study, fuel consumption and greenhouse gases emissions values for each farm operation of soybean production was evaluated in Gorgan and Ali-Abad Katol. For this purpose all operations activities were monitored and recorded in 26 fields. Results showed that the time required to perform various operations took between 0.2-3.9 hours per hectare. Fuel consumption values for various operations were between 3-38.1 liters per hectare. Among agronomic operation 3-bottom chisel plow consumed the highest fuel. As well, energy consumption of operations was between 138.9-1707 MJ per hectare. In the case of greenhouse gases emissions from different operations estimated from 12.5 to 170.9 kilogram carbon dioxide equivalent per hectare. Based on the result of this study, it is possible to compare different scenarios of soybean production in terms of energy consumption and greenhouse gases emissions to select the best production scenario(s).

Stem reserve remobilization is very important to keep the grain yield in wheat under terminal drought but the importance of this mechanism is unclear under terminal salinity. In this research stem reserve remobilization under terminal salinity were studied in greenhouse on four genotypes (No14 and No49, different in remobilization, and Bam as salt-tolerant and Ghods as salt-sensitive cultivars). Saline water (EC=15 dSm-1) was applied from anthesis. The experiment was conducted using a completely randomized design with factorial arrangement with three replications. Stem sampling was done five times with seven days intervals from anthesis, and stem dry weight, weight density and total water soluble carbohydrates (WSC), remobilization and its efficiency and grain yield were measured. The results showed that the highest grain yield, remobilization and contribution of remobilization in yield production were related to Bam and the most yield loss was related to Ghods. Based on the results, Bam with the highest remobilization efficiency had the most WSC production and remobilization under stress. A significant positive correlation between remobilization and yield production under terminal salinity showed that in spite of application of saline water at anthesis stage and continuation of photosynthesis up to the middle of the grain filling period, remobilization also had a great contribution on yield production in tolerant genotypes under salt stress.

In order to evaluation the effect of Mycorrhiza and Azospirillum on some characteristics of wheat cultivars in stablishment stage, an experiment was conducted in the research station of Shahid Chamran University of Ahvaz, Iran in 2012-13. The experiment carried out in factorial arrangement based on randomized complete blocks design with three replications. The treatments including of Mycorrhiza fungi in three levels (non application and application Glomus intraradices and Glomus mossaae strain), Azospirillum lipoferum in two-levels (non-inoculated seeds and inoculated seed and two wheat cultivars in three levels, (Chamran (bread wheat), Dena and Behrang (durum wheat) varieties). The root and shoots characteristics were measured in stablishment stage. Results showed that inculation of seeds with Azospirillum increased plant height, root volume, root dimeter, and root dry weight around 8, 11, 9 and 10 percent, repectivly. Mycorrhiza fungi compared with control improved all parameters 3% to 13%. Also in cultivar comparison, in most of the measurements Chamran was superior to durum cultivars (up to 23%). In general, the maximum root volume (2.18 cm3), root surface (20.99 cm2) and root dry weight (0.13 g) were obtained from inoculation of C.V Chamran seeds with Azospirillum lipoferum and G. mossaae strain. Thus concurrent application of G. mossaae and A. lipoferum have had the greatest impact on growth of wheat root cultivars and caused to additional root growth development in the early growth stages.

To evaluate quantitative and qualitative of yield and yield components of two cultivars of basil (Ocimum basilicum L.) medicinal plant as affected by planting pattern and plant density, an experiment carried out in 2009. This experiment was performed in factorial arrangement based on randomized complete block design with three replications in research farm of Azad university of Takestan, Iran. Two varieties (green and purple) of basil, two planting patterns (single and double row) and four plant densities (40, 60, 80 and 100 per m2) comprised experimental factors. Results showed that the interaction effect between varieties× planting patterns × plant densities was significant for spike number per plant, achene number per plant, seed number per achene, seed and essence yield except 1000-seed weight and essence percent. The highest number of spike (14.33) and achene number per plant (45) were obtained in green basil variety, double row planting pattern and density of 40 plants per m2. Also, the highest seed yield (2920 kg/ha) was observed in green basil variety, double row planting pattern and density of 100 plants per m2. In addition, the interaction effects between purple basil variety´40 plants per m2 and purple basil variety´double row planting pattern×40 plants per m2 had the highest essence content (0.37 and 0.36 percent), respectively. But the interaction between purple basil variety´double row planting pattern´40 plants per m2 showed the greatest essence yield (54.56 kg/ha). The lowest number of spike (9.33) and achene number per plant (22.33) were observed in purple basil variety, single and double row planting pattern and density of 100 plants per m2. In general, results showed that with increment of plant density per unit area and decrement of row spacing, essence content and essence yield decreased. In this experiment, purple basil showed superiority to green basil variety for yield quality as affected by planting pattern and plant density per unit of area. In this experiment purple basil with double row planting and 40 plants per m2 had higher yield quantity than green basil.

In order to evaluate drought tolerance of some Aegilops triuncialis ecotypes a factorial experiment based on a completely randomized design was conducted under non-stress and terminal drought stress (irrigation until 50% of heading) condition in the greenhouse of Mohaghegh Ardabili University in 2012. Drought tolerance and susceptibility indices for grain yield were calculated and principal component analysis was performed based on these indices. The results showed that based on the stress susceptibility index (SSI) and stress tolerance index (TOLI) Horand and Karaj ecotypes are less sensitive to water stress. In terms of stress tolerance index (STI) and geometric mean productivity index (GMP) which a high values of them indicates tolerance of studied ecotypes, Hashtrood ecotype were identified as a tolerant ecotype. Clustering of ecotypes in a three dimensional graph based on the yield in non-stress (Yp), in stress condition (Ys) and stress tolerance index (STI), showed that Maku and Hashtrood ecotypes under both non-stress and drought stress conditions, and Horand ecotype under stress condition have higher performance. With principal components analysis and biplot diagram, Hashtrood, Maku and Horand ecotypes were identified as drought tolerant. According to significant correlation among STI, GMP, MSTI1 and MSTI2 indices with yield under stress and non-stress conditions, these indices could be used for determination of tolerant ecotypes.

In order to evaluate times and rate of zinc fertilizer application on quantity and quality of faba bean, an experiment was carried out with factorial arrangement in randomized complete block design with four replications at research farm of Gonbad Kavous University during 2009- 2010. Two times of application were before flowering and beginning of pod setting and five rates of application was 0, 1, 2, 3 and 4 liter/ha of zinc solution (15%). Results showed that pod coat weight (a=0.01) and number of filled pods/plant, seed weight/pod coat weight and protein percentage of seeds (a=0.05) were significantly affected by time of zinc application. Effect of zinc rates on all traits were significant (a=0.01). Pod coat weight and number of filled pod/plant at first time of zinc application were higher than second time but seed weight/pod coat weight and protein percentage of seeds at second time of zinc application were higher than first time. Minimum and maximum of filled pod/plant, seed/pod, seed/plant, 100-seed weight, seed yield, pod coat weight, seed weight/pod coat weight, protein percentage, protein yield and relative yield belonged to none application of zinc and application of 4 lit/ha, respectively. None application of zinc treatment produced 2597 kg/ha and application of 4 lit/ha treatment produced 3993 kg seeds/ha.

In order to investigate the effects of inoculation of fungal endophytes Piriformospora indica and bacteria symbiosis Azospirillum Spp on growth and physiological characterization of alfalfa forage under salt stress, an experiment was conducted in a factorial arrangement in a completely randomized block design with three replications in the Agricultural Research greenhouse of Ilam University. The treatments were two levels of application of fungal endophytes (fungi P.indica bacteria Azospirillum Spp (inoculated and non- inoculated), inoculated with fungus and bacteria and integrated control of soil salinity levels (0, 2, 4 g cholorid sodium/ kg soil), respectively. Nutritional response included nitrogen, phosphor, potash, calcium, sodium and chloride absorption and physiological responses of alfalfa included proline and chlorophyll concentration and biomass production. P.indica fungi had positive and statistically significant effect on growth, fresh and dry weight of forage, photosynthesis pigment, proline and nutrient uptake under saline conditions. Fungi inoculation reduced the adverse effects of salinity by reducing toxic absorption of sodium and chloride and increased chlorophyll content of alfalfa hay. Alfalfa inoculated with bacteria produced more proline and chlorophyll content. Inoculation with Rhizobium bacteria had more favorable effect on chlorophyll content, proline and nutrient. The results showed that application of these microorganisms reduced salinity effect on plant.

In order to study the density and diversity of weeds and yield of barley and hairy vetch affected by mixed intercropping ratios, a field experiment was performed based on a randomized complete block design with four replications at the Agricultural Research Station, College of Agriculture, Ferdowsi University of Mashhad during 2012-2013 growing season. Ratios of mixed intercropping were 75% hairy vetch+25% barley, 50% hairy vetch+50% barley, 25% hairy vetch+75% barley and their monoculture. Weed samplings were done at two stages including after seedling emergence and canopy closure of two crops. The results indicated that the effects of mixed intercropping ratios of barley with hairy vetch were significant (P£0.01) on density and dry weight of weeds for narrow and broad leaves in two sampling stages, yield components, yield and land equivalent ratio (LER) based on biological and seed yields. The lowest and the highest weed number for the first and the second stages were observed in 75% hairy vetch+25% barley (with six and three species) and barley monoculture (with nine and seven species), respectively. For the first and the second sampling stages, the highest Shannon-Weiner diversities were calculated in barley monoculture with 0.96 and 0.72, respectively. The maximum biological yield and seed yield of hairy vetch were achieved in its monoculture with 927.5 and 495.6 kg.ha-1, respectively. Whereas the highest biological yield and seed yield of barley were obtained in its monoculture with 14780.9 and 7384.6 kg.ha-1, respectively. By increasing of intercropped hairy vetch ratio declined its yield components and improved yield components of barley. The maximum LER based on biological yield and seed yield were observed in 50% hairy vetch+50%barley with 1.21 and 1.20, respectively. In general, intercropping of barley with hairy vetch increased yield and yield components and declined weed density. So the best combination was 50%hairy vetch+50% barley.

Seeds deterioration is a natural phenomenon that occurs in all seeds and leading to gradual decline of seed viability during storage. However, the rate at which seeds age depends upon their physiological status, genetic constitution and storage conditions. In this study we the examined relationship among accumulation of reducing and non-reducing of sugars, soluble protein, the activity of free radical detoxifying enzymes, and seed deterioration in medicinal pumpkin (Cucurbita pepo subsp. Pepo. Convar. Pepo var. styriaca Greb) during storage. The seeds were incubated at different storage conditions of temperature (35 and 5oC) and seed moisture content (5, 8 and 14%) for 2 and 4 days. The accumulation of reducing sugars increased and soluble proteins and non-reducing sugars decreased during storage with increasing moisture content and temperature, suggesting that seed deterioration was associated with Amadori and Maillard reactions. The decrease in soluble proteins was related to increase electrical conductivity, which suggests membrane damage during deterioration. The increase in electrical conductivity may result from some disorders in protein components of the membrane, which arise from non-enzymatic glycosylation of proteins by reducing sugars in the Amadori and Maillard reactions. The decrease in germination was also associated with a decrease in catalase and peroxidase activity and as a result the antioxidant system was not sufficient to protect seeds against free radical damage. These results suggest that the accumulation of reducing sugar and decrease of soluble protein are coupled with Amadori and Maillard reactions and these reactions are responsible for medicinal pumpkin seed deterioration during seed ageing.

Water use efficiency is positively correlated with grain yield, and being used for indirect selection of high wheat yield in drought prone environments. However, there is not enough knowledge about genetic control of water use efficiency. In this research, a half diallel mating design was generated from crosses among 8 bread wheat genotypes to study the genetic of water use efficiency. Parents and F1 progenies were planted in drought stress condition in a randomized complete block design with four replications. Water uptake, grain yield, water use efficiency, awn length, fertile tiller number, grains per spike, 1000-grain weight and harvest index were evaluated. Additive and dominant controlled all traits, significantly. Non-additive variation was more important for controlling water uptake, grain yield, water use efficiency, fertile tiller number, 1000-grain weight and harvest index. Accordingly, bulk, single seed descent and double-haploid methods are suggested in breeding program for these characters. Whereas, additive variation had imperative effect on genotypic variation of awn length and grains number per spike. Thus, in spite of mentioned breeding methods, pedigree and backcross are recommended for these traits. Significant and high correlation (r=0.88**) between grain yield and water use efficiency demonstrated the importance of water use efficiency in drought stress condition. Therefore, selection for higher water use efficiency would improve grain yield in drought stress condition.

In order to identify the suitable rapeseed genotypes as second crop in paddy fields of Guilan province, 14 rapeseed genotypes were grown in complete randomized block design with three replicates in a paddy fields experimental condition in Rice Research Institute of Iran, Rasht during 2005-2007 cropping seasons. The results of the combined analysis of variance indicated significant difference among rapeseed genotypes, year and year´genotype interaction effect for most of evaluated traits. Mean comparison of yield and other traits showed that Hyola 330 and Hyola 401 produced maximum grain yield with average of 3400 and 3298 Kg/ha, respectively. Hyola 330 was in the first rank for most studied traits. Hyola 401 and Hyola 308 had the highest silique numbers per plant and the lowest days to maturity, respectively. Genotypes Hyola 330, Hyola 420 and Hyola 401 were in a group and had the highest oil yield. Also, cluster analysis put these genotypes in a group together. According to the analysis of variance and slicing the interactions, Hyola 401 due to high yielding and earlier maturity in both years is recommended as superior genotypes for cultivation in paddy Rasht.