جستجوی مقالات مرتبط با کلیدواژه « forage maize » در نشریات گروه « اکولوژی »

Maize (Zea mays L.) ranks first in terms of forage production among forage plants by producing about 490 million tons of fresh and silage forage in the world. Chemical fertilizers are used to increase crop yields and provide human food, but reduce soil organic matter content and, in the long run, pose a serious environmental risk, resulting in contamination of arable soils and surface and groundwater. Organic manures reduce the harmful effects of chemical fertilizers by producing humus and increasing the activity of the soil microbial community. Utilization of non-chemical resources such as farmyard manure in combination with chemical fertilizers can lead to soil fertility and increase yield and crop quality because combined fertilizer systems can provide most of the plant's nutritional needs by increasing the absorption efficiency of nutrients in crops. Considering the importance of organic manures and their combination with chemical fertilizers, this experiment was conducted in order to investigate the effects of different levels of poultry manure, chemical fertilizer, and their combination on yield, yield components, and maize forage quality.

The research was carried out in the research farm of Kurdistan University located in Dehgolan County, Kurdistan Province, Iran in the crop year 2017-2018. The experiment was performed in the form of randomized complete blocks with three replications. Experimental treatments included different levels of pelleted poultry manure in combination with chemical fertilizers: Figure 2. T1: no fertilizer (control), T2: 1250 kg of poultry manure + zero kg of recommended chemical fertilizer, T3: 1250 kg of poultry manure + 25% of the recommended chemical fertilizer, T4: 1250 kg of poultry manure + 50% recommended chemical fertilizer, T5: 2500 kg of poultry manure + zero kg of recommended chemical fertilizer, T6: 2500 kg of poultry manure + 25% of recommended chemical fertilizer, T7: 2500 kg of poultry manure + 50% Recommended chemical fertilizer, T8: 5000 kg of poultry manure + 0 kg of recommended chemical fertilizer, T9: 5000 kg of poultry manure + 25% of recommended chemical fertilizer, T10: 5000 kg of poultry manure + 50% of chemical fertilizer Recommended, T11: 100% recommended chemical fertilizer. In this experiment, traits such as plant height, 1000-seed weight, biological and grain yield, seed nitrogen, starch, oil contents and forage quality were measured.

The results of the analysis of variance showed that the plant height, grain yield, biological yield, grain nitrogen, starch and oil contents, and oil yield were affected by fertilizer treatments at a probability level of 1%. The index harvest of maize was significant at the level of 5% probability. The number of plants per square meter and 1000-seed weight were not affected by fertilizer treatment. The highest plant height (241.2 cm), number of ears per plant (1.2 ears), 1000-seed weight (26.99 g.m-2), seed yield (12.76 tons per hectare) and biological yield (26.42 tons per hectare) were observed in the treatment of 5000 kg of plated chicken manure + 50% of the recommended chemical fertilizer. The highest percentage of fodder silage protein (12.58%) and silage ash (10.32%) was observed in the treatment of 2500 kg of plated chicken manure + 50% of the recommended chemical fertilizer. The highest percentage of insoluble fibers in neutral detergent was observed in the T6 and T8 treatments, and the lowest percentage of insoluble fibers in neutral detergents was observed in the T10 treatment. The highest and lowest percentages of insoluble fibers in acidic detergent were in the T2, T4, and T3 treatments, respectively. According to the results of the present experiment, the combination of chemical fertilizer with different amounts of chicken manure has reduced the consumption of chemical fertilizers, and in addition to saving on the consumption of fertilizer and the resulting costs, the harmful effects on the environment have also been reduced, and the condition of the soil in terms of fertility in the long term, the percentage of soil organic matter will improve.

 The results of the experiment showed that combined fertilizer treatments were superior compared to pure chemical fertilizer and pure poultry manure treatments, improved the yield and yield components of maize and caused a reduction in chemical fertilizers consumption. Chemical fertilizer treatment provided acceptable yield only at high levels.

Biofertilizers include one or more species of high-density soil organisms which are used in sustainable farms with the aim of increasing soil fertility and plant access to nutrients. This experiment was performed to evaluate yield and growth indices of maize at different sowing dates under the influence of mycorrhizal fungi.

The experiment was conducted in the research farm of Kurdistan University in 2017 as a factorial based on a randomized complete block design with three replications. Factors included mycorrhizal fungi at four levels including (Funneliformis mossea), (Rhizophagus intraradices), (Funneliformis mossea + Rhizophagus intraradices) and without mycorrhiza (control) and sowing date at three levels (6, 16 and 26 July). In this experiment, growth indices and traits related to maize yield were measured.

The results showed that the highest leaf area index, growth rate and dry matter accumulation were obtained on 6 July sowing date and 26 July had the lowest values. The highest values of leaf area index and crop growth rate were related to Rhizophagus intraradices treatment. Application of mycorrhiza increased dry matter accumulation and as a result, maize yield compared to the control treatment. The interaction of mycorrhiza fungus and sowing date caused a significant increase in cob dry weight and biological yield.

The results showed that the combined treatment of 6 July planting date and Rhizophagus intraradices fungus was superior in terms of growth indices, cob and plant dry weight and biological yield.

Conservative agriculture with minimal adverse effects on the environment has been the subject of great interest recently as a means of promoting sustainable crop production and food security (Nkala etal., 2011). The approach is practiced in large-scale commercial agriculture. Conservative agriculture also encourages the optimal utilization of resources such as soil and water and helps the sustainability of products in the agroecosystem (Stavi etal., 2016). Nonetheless, due to the diversity of conservation farming operations around the world, it is critical to prioritize different tillage methods according to cultivation conditions and climatic conditions (Miller et al., 2012). The main objective of this study was i) to assess the efficacy of different conservative soil tillage (minimum and/or zero tillage) in combination with crop residue and fertilizer management in achieving maximum crop production; and ii) to assess the effects of management practices on agroecosystem performance using agronomic and environmental data and scoring function descriptions.
To achieve the goals, a field experiment was carried out involving 7 treatments with varying combinations of different tillage methods, crop residues and fertilizer management on a field of maize which was planted after the cultivation of a wheat crop. At the end of the growing season, the chemical and physical soil properties as well as the total yield of corn were measured. The physical and chemical parameters measured in the soil included electrical conductivity, field capacity, available water, porosity, pH, soil organic carbon, total crop biomass and maize yield. Agroecosystem performance was assessed using a computer program entitled the AgroEcosystem Performance Assessment Tool (AEPAT). It utilizes performance-based index methodology to derive a relative ranking of agroecosystem performance among management practices for functions and indicators included in the procedure. Data measured by the software AEPAT are rated from 0-100 to calculate two agroecosystem functions including conservation agriculture and food production.
The results showed that “stalk chopper瘫᳻崴 kg N-fertilizer瘫岅” treatment resulted in the maximum amounts for field capacity (25.63%), available water (15.63%), porosity (49.2%) and organic carbon (0.73%). The highest total biomass (87.3 th-1) and ear yield (23.8 tha-1) was also obtained using this treatment. In contrast, the lowest amounts for these parameters were obtained with the “stubble burning disc ditcher” treatment. This was due to the stubble burning which increased the soil electrical conductivity and reduced the physical and chemical soil quality. On the other hand, leaving the on-farm residue in place plays an important role in regulating electrical conductivity and soil salinity. It can be concluded that the type of agriculture practiced affects the soil physicochemical properties to a high extent. Leaving crop residue in the field may increase the soil biological activity resulting in soil porosity and aggregation. The analysis on sustainability of agricultural practices showed that “stalk chopper瘫᳻崴 kg N-fertilizer瘫岅” treatment had the highest score for agroecosystem performance (61.21) in terms of both optimum yield and sustainability. The lowest score of 7.63 was obtained with “stubble burning瘫᳹�爗” treatment.
In conclusion, it was demonstrated that conservative tillage in combination with crop residue not only led to a higher maize yield but also improved the soil quality. Nonetheless, for conservative tillage to be effective adequate N-fertilizer, as a starter to provide needed crop growth nutrients, must be applied. In addition, the efficiency of the indexing score is critical in discriminating between different agricultural practices within and across agroecosystem functions. The agricultural practices had a direct effect on agroecosystem performance and the soil physicochemical properties can be used as an index to assess agroecosystem function and performance.

In order to investigate the effect of sowing date and plant density on morphology, phenology and yield variables of 704, 540 and 500 maize hybrids, a factorial experiment was carried out based on complete randomized block design with four replications. In this research, row space was fixed at 75cm and inter row spacing was 12, 15 and 18cm that create 111500, 89000 and 74000 plants per hectare, respectively. In this study, the highest number of kernel rows per ear, with 18. rows, was obtained by hybrid 500. Whereas, the highest number of kernels per row, with 24.4 kernels, was produced by hybrid 704. But, among studied hybrids, the number of kernel per ear was not significant. The results also showed that the highest forage yield, with 48.1 ton per hectare, was obtained by hybrid 704 and hybrids 540 and 500 with 42.6 and 40.8 ton forage yield per hectare ranked next, respectively. High performance of hybrid 704 depends on its high biomass production so that the dry weight of hybrid 704 was 118.9 gram per plant that had significantly differences compared to other hybrids. With increasing of plant density, forage yield per plant was decreased significantly and forage yield per unit area was increased. The highest forage yield per unit area, with 46.3 ton per hectare, was acquired from 12cm row spacing. The study of phonological traits demonstrated that in Bonab region only hybrid 500 could reach to maturity stage (dough stage) for harvest. With respect to high quality of maize forage for silage at dough stage, the hybrid 500 for is suitable and if the purpose is grazing, sown of hybrid 704 with highest density is recommended.

In order to evaluate the effects of drought stress, poultry litter and urea fertilizers on agronomic properties of forage maize (cv. SC704), a spilt-plot experiment arranged in randomized complete blocks design was conducted with four replications at the research station of Shahrekord University in 2009. The main plots consisted of irrigation treatments at two levels, normal irrigation and irrigation stop at pollination stage for two weeks. Sub-plots were assigned to fertilizer treatments with three levels of urea fertilizer (F1=217, F2=435 and F3=652 kg ha-1), and three levels of poultry litter (F4=5.28, F5=10.57 and F6=15.86 Mg ha-1) and F0 as the control (no fertilizer) treatment. Results showed that drought stress had a significant effect on stem and ear fresh weights, ear diameter and fresh forage yield, but not on green and yellow leaf numbers, leaf area index, tasselling and silking creation, anthesis–silking interval, plant height, stem diameter, ear length and leaf fresh weight. The effects of fertilizer treatments were significant on all the measured characters with the exception of leaf numbers. The application of nitrogen resulted in an increase in forage yield, most likely due to increased leaf area index, leaves, stem and cob weights, length and diameter of cob, stem diameter, plant height and decreased anthesis–silking interval in N-fertilized treatments. Poultry litter and urea fertilizer × drought stress interactions were observed for leaf area index, leaf and stem fresh weights. The highest fresh forage yield (101 Mg ha-1) was observed in the normal irrigation and 15.86 t ha-1of poultry litter treatments that significantly differed from other treatments. However, if a large quantity of poultry litter is unavailable, 10.57 t ha-1 of this manure that had no significant differences as compared with 652 kg ha-1 of urea fertilizer, would lead to an optimum yield.