JOURNAL OF AGRICULTURAL SCIENCE AND SUSTAINABLE PRODUCTION
Year:2012 | Volume:22 | Issue:1|Papers Count:13

Different approaches are used to explain sustainable agriculture. Grey programming is one of the approaches that has been used widely in this field. A new version of this method in the form of Fractional Fuzzy programming with and without multiple goals has been used in different fields. However, this method is not planned in the form of gray programming. In this study, first grey fractional programming is introduced and an application has been shown for cropping pattern in line with sustainable agriculture. Results showed that dry and rain fed wheat area in the region is between (7135.5, 17331.6) and (4702.6, 12687.2) acres, respectively. Also, dry and rain fed barely area are changed between (0, 1232.8) and (1032.3) acres, respectively. Upper bound of alfalfa and sugar beet area in sustainable pattern is 3804.3 and 1854, respectively that is less than the current cropping pattern and would cause profit reduction of the current pattern. Results showed that the sustainability index with respect to nitrate fertilizer in fractional programming case is in the range of grey fractional interval model and has improved than the current pattern. Also, the current area of wheat is in the range of sustainable agriculture.

The soybean crop growing consists of vegetative, flowering and grain filling stages which any stage has different sensitivity to water deficit. Main aim of this experiment is determining of most sensitive growing stage to drought stress and estimating of yield reaction coefficient during water shortage period and water use efficiency. Then, an experiment with complete randomized block design by 3 replication and 7 water treatment accomplished for JK cultivar of soybean in spring cultivation. Water deficit treatments at different growing stages consists of: TR, irrigation in whole growing period (Control Treatment), TR1, Irrigation with moisture stress in vegetative stage, TR2, Irrigation with moisture stress in flowering stage, TR3, Irrigation with moisture stress in grain filling stage, TR4, Irrigation with moisture stress in vegetative stage and flowering stage, TR5, Irrigation with moisture stress in vegetative stage and grain filling stage, TR6, Irrigation with moisture stress in flowering stage and grain filling stage. Results shows that flowering stage is most sensitive stage for soybean growing period in Mazandaran Province. In TR1 Treatment, water consumption reduced 28% while 4% reduction of yield was observed. TR1, also has Maximum water use efficiency. Yield response factor (Ky) was 0.87 for the total growth period. The flowering stage of soybean was most sensitive and Maximum WUE is related to the treatment of stress in the vegetative growth stage.

Sweet basil (Ocimum basilicum L.) is one of the most important medicinal plants that its essential oil used in different medicinal industries. In this research, effects of different types of fertilizers were evaluated on quantitative and qualitative characteristics of basil. The research was conducted under field condition in complete randomized block design with three replications. The treatments included vermicompost, livestock manure chemical fertilizer, biofertilizer (Azospirillum/ Azotobacter), combinations of vermicompost and 50% chemical fertilizer, combinations of biofertilizers and 50% chemical fertilizer, manure and control. The highest dry yield in first and second harvest observed in combinations of biofertilizer and 50% chemical fertilizer. Results showed highest essential oil content obtained in chemical fertilizer and combinations of biofertilizer and 50% chemical fertilizer. According to the results, application of chemical fertilizer, biofertilizer and combinations of biofertilizer and 50% chemical fertilizer increased essential oil yield to 41%, 33% and 38%, respectively. Identification of essential oil components showed that content of Eugenol and Methyl chavicol increased with application of nitrogen fertilizers. It is concluded that application of biofertilizers enhanced quantitative and qualitative characteristics in this plant. Generally, it seems that using of biofertilizers could improve basil performance in addition to reduction of environmental pollution.

In this study, the cultivation of pomegranate (Punica granatum) with respect to the ecological requirements of these species was studied. In order to determine the ecological requirements of this species including: elevation, aspect, slope, type of soil and feasibility study it. The questionnaire prepared was to the Delphi method and provided 64 natural resources experts and university professors. Evaluation of habitat conditions using approach AHP of MADM method. Using the scoring criteria whit AHP calculated was weight each criterion in Expert Choice software. In this research using AHP and GIS used evaluation criteria and analyzed were topographic data In GIS. For Integration layers used was overlay method and integrated were data generated with GIS. Using this method and data transmission shown to be condition ecological capability on the map. Finally, using the results of the analysis of factors affecting introduced was spatial distribution of this species. The results of this study indicate the cultivation of Punica granatum about 1988 hectares equivalent to 72.34% of Bolhasan forest in excellent condition, 1577 ha equivalent to 55.27% in a good condition and 2160 ha equivalent to 73.37% in poor condition.

In this study, the antagonistic effect of Trichoderma harzianum T100 as a potential biocontrol agent against soybean charcoal rot caused by Macrophomina phaseolina were evaluated in in vitro and in vivo conditions. In dual culture tests, isolate T100 inhibited the mycelial growth of pathogen (55.3%), then over ran and sporulated on the mycelia of M. phaseolina. Microscopic examination of mycelial interaction sites of T. harzianum and M. phaseolina showed that T100 penetrated mycelial cells of pathogen, moved inside and lysed them. Volatile test results indicated that the antagonist inhibited the mycelial growth of pathogen (12.2%) and decreased the production of microsclerotia in culture media. Data from greenhouse experiments showed that, treatment of soil with T. harzianum T100 resulted in a high percentage of fresh and dry weights of root (57.5% and 53.6%) and aerial parts (22.9% and 11.8%) of soybean in sterile soil in compared with control. Additionally, reduction of microsclerotial formation on soybean root and steam, microsclerotial coverage, (62.5%) showed the antagonist ability for initial inoculums reduction in later season.

The experiment was carried out as randomized complete block design in factorial with three replications to evaluate of the possibility of integrated weed management in Broomcorn (Sorghum bicolor) yield. Treatments were included herbicides (Foramsulfuron, Bromoxynil+MCPA and 2, 4-D+ MCPA), application dose (recommendation dose, 25% less and more than recommended doses for corn farms) and mechanical control (with or without cultivation). The result indicated all factors including herbicides, application doses and cultivation were significantly influenced weeds density and dry weight. The best herbicide in weeds density and dry weight decreasing percentage was Foramsulfuron treatment. Cultivation treatment was significantly influenced weeds control. The best doses were 25% more recommended dose and recommended dose on weeds density and dry weight decreasing percentage.

In order to study the effects of different nitrogen (0, 25 and 50 Kg.ha-1) levels and two levels of Nitroxin biofertilizer (control and inoculation) on yield and its components in three sesame varietes (Darab-14, Jiroft and Yazdi) an experiment was conducted at Agricultural Research Center and Natural Resources of Yazd in 2009. Varietes in main plot, nitrogen fertilizer and biofertilizer as factorial were randomized in sub-plots used in a split plot factorial arranged as a randomized complete block design with three replications. Plant height, number of capsules per plant, number of branches per plant, number of seeds in capsule, 1000 seed weight, seed yield, harvest index, oil percent, oil yield and protein percent were measured. Concerning the effect of varietal differences, results illustrate significance differences between the three varieties in all determined characters except for oil percent. Different nitrogen fertilizer and biofertilizer significantly affected in all determined characters except for oil percent and harvest index. The highest seed yield (1794.4 kg.ha-1) and Protein percent (22.48%) was obtained using Darab-14 with applying 50 kg N ha-1 and applying biofertilizer treatment. Seed yield had positive and significant correlation with capsules and branches per plant, number of seeds in capsul, protein percent and oil yield. Generally, the results showed that use of biofertilizer can be useful in during the decrease use of N chemical fertilizer.

Salicylic acid is a plant hormone which had enhancing effects on growth and yield of plants under different environmental conditions. It is proposed, salicylic acid could be used as growth regulator for improving plant growth under water stress conditions. The effects of salicylic acid on yield and growth indices on safflower plants was investigated in a split, split plot in complete randomized block design. Water stress in two levels, normal irrigation and cut off irrigation after flowering, as main plot, safflower genotypes in four levels, including Isfehan Local, Gilla, Lesaf and Dincer, as sub plots and priming in five levels, including 0, 700, 1400, 2100 and 2800 µM salicylic acid as sub, sub plot were studied. Results showed that plants in normal conditions had highest leaf area index (LAI), leaf area duration (LAD), net assimilation rate (NAR), seed yield and seed and oil harvest index compared to plants in stress conditions. Water stress leads to rapid decrease in leaf area and decrease of greenness period. Among the genotypes, Dincer and follow it, Lesaf in both irrigated and stress conditions had highest LAI, specific leaf weight, LAD, NAR, seed yield and seed and oil harvest index. Also, Dicer had lowest leaf area ratio (LAR). By contrast, Gilla had highest LAR and lowest seed yield. In irrigated plots, plants which primed with 2800 mM salicylic acid had highest seed yield and growth indices. On the other hand, under stress condition treated plants with 1400 mM salicylic acid had better performance. It is possible in higher priming levels, plants had more leaf area and because of higher transpiration and rapid loss of storage soil water, they had not enough moisture in grain filling period. Therefore, treatments with lower leaf area had better performance.

To study the effect of conservation tillage on irrigation scheduling and quantitative and qualitative characteristics of spring rapeseed (RGS 003), a split-plot experiment based on randomized complete block design with 3 replications was conducted in sandy-clay-loam soil of East Azerbaijan region. The tillage treatments were: T1: conventional tillage, T2: reduce tillage, T3: no-tillage. The irrigation treatments were irrigation after 25 (I1), 50 (I2) and 75 (I3) percent of moisture depletion in root zone. The water consumption was calculated by measuring soil moisture content in the root zone. Results indicated that, tillage and irrigation treatments had significant effects on grain and oil yield (p<0.01). The interaction effects of these treatments was not significant. Since this experiment was carried out in one year, the effects of conservation tillage were not visible. However, treatment T1I2 resulted in maximum grain and oil yields (1012, 392 kg/ha, respectively) with 7620 m3/ha water consumption was recommendable.

In order to study different times of cultivating and type of medical and cover plants on performance and weed biomass of corn (single cross 504), the experiment was carried out in 2010-2011 in research farm of the agriculture faculty of university of Tabriz. The experiment was carried out in a factorial arrangement with the base of randomized complete block design in three repetications. The treatments of this experiment included type of medical and cover plant in 4 levels (Clover, hairy vetch, basil and dill) as first factorial and time of cultivating cover and medical plant in tow levels (synchronic cultivation with corn and cultivation 15 days after corn cultivation) as second factorial. The results showed that the ear height, the number of grain row per ear and yield of grain lied under effect of the time of cultivation and the type of cover plants as the highest amount of these traits were seen in treatment of the corn with clover and the lowest amount were seen in the treatment of the corn with dill. Treatment composition of cover plant × the time of cultivation on ear diameter and weight of 100 grain was significant and in both traits, ear diameter and weigh of 100 grain, the treatment of synchronic cultivation of corn with clover and the treatment of dill with 15 days delay in comparison of the cultivation of corn had the highest and lowest amount, respectively. Also, the highest weed biomass was seen in dill treatment with 15 delay than corn cultivation and the lowest amount was seen in synchronic cultivation of clover with corn.

Removing subsidies of agricultural inputs such as fertilizers and pesticides have been regarded, because of their unintended consequences such as inputs non-optimal usage, increasing of administrative costs and decreasing in economic growth of countries. With regards to producing about 200000 tons onions in Eastern Azerbaijan, this study has been carried out with the aim of evaluating the removing of fertilizer`s subsidies in Tabriz plain. For this subject, necessary data were collected by completion of 200 questionnaires of local farmers in farming crop year of 2008-2009. Data were analyzed by using of quadratic generalized production function approach. The result of fertilizer demand elasticity showed that the price liberalization decreases the fertilizer’s usage, but does not make significant effect on its usage. Removal of fertilizer subsidy may cause to reality of its price, so regarding the fertilizer’s non-economic usage, this policy can help to decrease in fertilizer’s consumption and finally help to production process to be more economic. The results showed that fertilizer is an essential input in the producing of onions in Tabriz plain, and even with the price liberalization policy, farmers did not decrease obviously in fertilizer consumption. Because of its over-optimized usage, removal of subsidy will cause decrease in its use, and finally it could help to more economical of production.

There are several methods for weed management which one of them is using allelopathic crops. The present study was conducted to investigate the allelopathic effects of rye on seed germination and also seedling growth of sweet corn and some of it’s important weeds including redroot pigweed, lambsquarters, johnsongrass and wild prosomillet in laboratory and greenhouse, based on randomized complete block design (RCBD) with 4 replications. In the laboratory conditions, the effects of different concentrations of the water extract of rye aboveground parts (0, 2.5, 3.75 and 5.0 gr.100 ml-1 water) and in the greenhouse conditions the effects of aboveground parts biomass (0, 4, 8, 16 and 32 gr of rye biomass per 1 kg soil) on germination and seedling growth indices of sweet corn and it’s major weeds were investigated. Rye aqueous extracts showed a negative effect on germination and seedling growth parameters of them. So that, in laboratory conditions, the seed germination of wild proso, lambsquarters, johnsongrass and redroot pigweed were reduced 84.7, 75, 53.3, and 31%, respectively in the highest concentration of rye extract compare of control. In contrast, there was not a considerable impact on corresponding indices of sweet corn. Seedling emergence of lambsquarters, johnsongrass, redroot pigweed, and wild proso were reduced 79.8, 75, 72.8, and 68.3% in 32 gr of rye biomass per 1 kg soil, respectively (in greenhouse conditions). Emergence rate of these weeds was reduced by rye biomass. Lambsquarters and redroot pigweed dry weight and length of root and shoot were reduced significantly by all levels of rye biomass. Finally rye residues have an enormous potential to suppress weed species with no harmful influence on sweet corn.