جستجوی مقالات مرتبط با کلیدواژه « corn » در نشریات گروه « زیست شناسی »

In order to evaluate the changes obtained from nitrogen, zinc and potassium sources on the morphophysiology of hybrid Maize SC704 experimental in the form of complete randomized block design in four replications was conducted in spring and summer of 2018 in Golestan province in an area located in Mazraeh Katoul. The treatment included nitrogen fertilizer, potassium, zinc alone, nitrogen + potassium, nitrogen + zinc, zinc + potassium, combined use of nitrogen + potassium + zinc, versus control. The results of analysis of variance showed that the treatments on grain yield, plant dry weight, corn length, chlorophyll a, chlorophyll b, total chlorophyll, silk soluble sugars and silk protein were significant at a probability level of one percent. Application of these fertilizers increased corn length, plant dry weight and grain yield, as well as increased sugars and silk protein of corn and photosynthetic pigments of corn and the highest content of photosynthetic pigments was observed in the treatment of application of potassium fertilizer alone and combined application of fertilizers (Zn + K+ N).

In order to evaluate the effect of boron and jasmonic acid foliar application on maize, under different irrigation regimes, an experiment was conducted as split-split plots in the form of a randomized complete block design in three replications in the summer of 2021 in the Varamin. In this experiment, irrigation was arranged in four levels (as the main factor): complete irrigation, stopping irrigation at the 8-leaf stage, stopping irrigation at the stage of cob emergence, and stopping irrigation at the stages of 8 leaves and cob emergence. Boron foliar application at three levels, including spraying with pure water, spraying with 0.5% boron, spraying with a solution with 1% boron, and spraying with jasmonic acid solution in three levels, including spraying with pure water, spraying with a concentration of 50 µM jasmonic acid, and spraying with a concentration of 100 µM jasmonic acid, were considered in sub-plots. The results showed that stopping irrigation at different stages of growth caused a decrease in all tested traits. Also, the results show that the spraying of 1% boron increases grain yield (5.5%), 1000 seed weight (2.9%), biological yield (2.8%), carotenoid content (11.2%), and decreases 4.4% of leaf malondialdehyde. On the other hand, the use of 100 µM jasmonic acid increases leaf chlorophyll content (2.69%), leaf carotenoid content (2.94%), 1000-seed weight (1.29%), seed yield (2.67%), and biological yield (2.95%). Indeed, the use of jasmonic acid also reduced the damage caused by oxidative stress by increasing the amount of the superoxide dismutase enzyme.

The effect of biofertilizers and plant density was investigated on yield and yield components of sweet corn cv. ‘Sari 2802’ in a split-plot field experiment based on a randomized complete block design with three replications in Lahijan, Guilan province in 2021. The main plot was assigned to biofertilizer at four levels of control (F1), using N-Fertile 1 (F2), phosphate fertile2 (F3), and N-Fertile 1 + Phosphate fertile 2 (F4), and the sub-plot was assigned to plant density at three levels of 55,000 (D1), 65,000 (D2), and 75,000 plants/ha (D3). The results showed that the application of biofertilizer influenced plant height, grain number per ear, ear length, total dry matter, grain yield, and 1000-grain weight positively. The highest 1000-grain weight (383 g), the highest total dry matter (26240 kg/ha), and the highest grain yield (9146 kg/ha) were obtained from F4D2 (N-1 + P-2 and the density of 65,000 plants/ha). The results showed that the density of 65,000 plants/ha and the application of N-1 and P-2 biofertilizers was the best treatment.

Corn is one of the valuable agricultural plants whose diversity, adaptability and high nutritional value have placed it among the most important agricultural plants in the world. Foliar spraying of nitrogen, zinc and potassium fertilizers on corn plants can provide farmers and researchers with very good information about the effect of nitrogen, zinc and potassium fertilizer consumption in the climatic conditions of Golestan province.

Considering the medicinal effects of corn cob and its importance in medicine and the presence of special effective substances in this connection in corn silk, it seems that their quantity and quality are affected by the use of nitrogen, zinc, and potassium. Therefore, examining these changes is one of the practical goals of this research.

In order to evaluate the changes resulted from nitrogen, zinc, potassium and their simultaneous application were done on some morphophysiological traits of single cross 704 hybrid maize as a randomized complete block design with four replications in spring and summer of 2019 in Golestan province, the Katoul farm. Treatments included nitrogen(N), potassium(P), zinc(Z) fertilizer and combined application of nitrogen+potassium(NP), nitrogen+zinc(NZ), potassium+zinc(PZ) and their combined application of nitrogen+potassium+zinc(NPZ) with control. The results showed the traits were affected by fertilizer sources significantly (p≤ 0.01).

The studied treatments had a significant effect on the traits of height to the first corn, number of rows, ear length and ear diameter at the time of full ripening at the probability level of (p≤ 0.01). With the application of zinc, nitrogen and potassium elements, a significant increase in the content of phenolic compounds of leaves, silk and corn seeds was observed. The flavonoids of leaves, silk and seeds were influenced by the supply of nitrogen (N), zinc (Zn), potassium (K) fertilizers and their simultaneous application. Leaf anthocyanin in foliar spraying treatments with single potassium fertilizer, due to creating optimal conditions, most of the current energy of the plant was spent in the direction of growth, development and increasing the yield of treated plants, so the biosynthesis and production of anthocyanin in corn leaves with single application of potassium was less, but silk anthocyanin And the seed with single application of potassium and simultaneous application of potassium+nitrogen, potassium+zinc, potassium+nitrogen+zinc showed a significant increase compared to the control.

according to the obtained results, the simultaneous application of fertilizers is recommended to increase the morpho-physiological traits and yield of plants.

Drought stress is one of the most important abiotic stresses and limiting factors for plant development and plant production. In order to evaluate the impact of concomitant application some of microorganisms and chemical compounds with three species of arbuscular mycorrhizal fungi Funneliformis mosseae, Rhizophagus intraradices and Claroideoglomus etunicatum as mycorrhizal inoculum on antioxidant enzymes activities and phenolic compounds in corn cultivar 705SC, an experiment was conducted in a randomized complete block design with three replications. In the present study, treatment of living and non-living compounds at seven levels (included Pseudomonas flurescens VUPF5, Issatchenkia orientalis yeast, Azolla, compost tea, humic acid, siderophore biologist, amino acid complex), treatment of arbuscular mycorrhizal (included three species of fungi and control) and drought stress at one level (30% of field capacity) were examined. Six, twelve and eighteen days after the start of drought stress, the interaction effect of treatments with species of arbuscular mycorrhiza on the activity of peroxidase, polyphenol oxidase, phenylalanine ammonialyase enzymes and total phenol was evaluated. According to the results, in all three fungal species, the activity of peroxidase enzyme in siderophore treatment with fungus was higher compared to other treatments. Also, the highest activity of polyphenol oxidase enzyme was observed in R. intraradices mixed with compost tea treatment. Phenolic compounds in mycorrhizal plants and non-mycorrhizal plants reached the highest level on the twelfth day, depending on the treatment and type of fungal species. In conclusion, among the different treatments inoculated with corn, amino acid complex, siderophore, tea compost and humic acid increased antioxidant enzyme activity compared to the control treatment and reached its maximum on the twelfth day..

In order to investigate and compare the allelopathic effects of Eucalyptus (E.globuhus Labill) leaf aqueous extract and leaf mulch on corn (Zea mays L.) and wild millet (Panicum miliaceum L.), a factorial experiment was conducted in a completely randomized in Ferdowsi University of Mashhad. The experiment was carried out in seedling stage to evaluate the allelopathic effect of leaf aqueous extract (5, 10, 15 and 20 g/L) and leaf mulch (3 and 5 %) on some morphological, physiological and biochemical characteristics of the plants in this stage. Aqueous extract of Eucalyptus leaf (in most cases) and leaf mulch reduced the height of shoot, the total length of roots, the fresh weight of shoot and root, the dry weight of shoot and roots. So that the highest reduction percentage of these traits was observed in the treatment of 20 g/L aqueous extracts on wild millet. Chlorophyll a, b and total, carotenoid contents and chlorophyll stability coefficient of corn seedlings showed an incremental increase (compared to control) when treated with leaf aqueous extract. While all photosynthetic traits of millet weed decreased under all the aqueous extract and mulch treatments. The increase and decrease of membrane stability coefficient were seen in corn and wild millet respectively, when they were affected with both kind of treatments. Although the accumulation of malondialdehyde was the highest in treated millet seedlings, but corn seedlings could significantly reduce the peroxidation of membrane lipids against the stress caused by leaf extract and mulch. More increasing effects of aqueous extract and mulch on total phenol content of corn than wild millet was another results of this study. Although the total protein content of corn and weed was decreased by both treatments, but the treatment of extracts could have a better boundary between the sensitivity of plants against the allelopathic stress. A significant reduction of nitrate reductase activity in wild millet was recorded under the treatments. According to the results of this study, leaf aqueous extract or powder has different effects on biochemical, physiological and developmental traits of crops and weeds. Considering the potential of Eucalyptus leaf extract and leaf mulch on corn and wild millet, it is recommended that the plant extract can be an ideal candidate (compared with leaf powder) as a natural herbicide to control millet grass in corn fields.

Deterioration of seed is one of the vigor reducing factors limiting seed germination. Determination of factors affecting seed deterioration is important. In order to determine the effect of plant hormones on germination characteristics and antioxidant enzymes activities of deteriorated corn seeds an experiment was carried out at seed and biotechnology laboratories of College of Agriculture, Tehran University in 2019. The study was designed with a factorial experiment based on completely randomized design (CRD) with four replications. The experiment treatments included varieties at 2 levels (704 single cross hybrid and 260 single cross hybrid), accelerated aging at 4 levels (0, 5, 10, and 15 day), and hormones at 2 levels (gibberellin and cytokinin). Seed deterioration reduced germination indexes and peroxidase and catalase enzymes activity. Treatment of deteriorated seeds with cytokinin and gibberellin increased antioxidant enzymes activities. Cytokinin was more effective than gibberellin in increasing the activities of antioxidant enzymes in deteriorated seeds. Results indicated that low seed vigor decreased the activity of enzymes and plant hormones as an agronomy solution compensated for the loss in low vigor seeds. Also, cultivar 704, with a higher vigor indicated amore enzyme activity than cultivar260.

In order to investigate the effect of drought stress by application of hormone and nanoparticulate spraying on corn biochemical traits, a split factorial was used in a randomized complete block design with four replications at the Agricultural Research Faculty of Islamic Azad University, Varamin. Drought stress in two levels (drought stress and drought stress) and three growth regulators (application of gibberellic acid (200 ppm), application of cytokine (200 ppm) and lack of application of regulator and growth hormone) and three levels of nano Particles (application of silver nanoparticles (0.02%), application of zinc nanoparticles (0.02%) and application of nanoparticles were considered. The results showed that in all drought stress conditions, the traits under study were affected so that the levels of malondialdehyde, proline, superoxide dismutase, catalase increased and leaf protein, alpha-amylase and soluble sugar decreased. The application of gibberellin and cytokinin as well as application of silver and zinc nanoparticles reduced the effects of drought stress. In drought stress conditions, growth regulator application and nanoparticles resulted in increased proline levels. The use of gibberellin hormone with the application of silver and zinc nanoparticles reduced the amount of protein in the leaf. According to the results, the application of growth regulators and nanoparticles can help improve plant performance under drought stress conditions.

In order to investigate the effect of application of biofertilizers and micronutrients on yield and yield components of corn (Zea mays L.) cultivar AS71, a research was conducted in Sarpol-e-Zahab city in 2017, in a factorial arrangement and complete block design Randomization was performed in three replications. Experimental treatments including bio-fertilizers at two levels of Phosphatebarvar-2 and Azotobarvar-1 and foliar application of micronutrients in four levels of control, zinc, manganese, and zinc and manganese foliar application. The results showed that the effect biofertilizers and micronutrients had a significant effect on plant height, stem diameter, number of grains per row, biological yield at 1% level, and hundred grains weight and harvest index at 5% level. The effect of micronutrients on ear length, number of grain rows per ear and grain yield was significantly affected. Comparison of mean of traits showed that the highest grain yield was obtained in foliar application of zinc with 15936 kg ha-1 . Biological yield with 32246.9 kg ha -1 in combination treatment of Azotobarvar-1 with Zn and Harvest index with 61.53 percent in combination treatment of Phosphatebarvar-2 and Zinc element were highest.

In order to investigate the effect of biological fertilizers (Azetobarvar-1 and Phosphate Barvar-2) on yield and yield components of corn (S.C. 704) under low irrigation conditions in second cropping, a split plot experiment was conducted in a randomized complete block design with three replications during 2016-2017. The main plots consisted of irrigation interruption at 8 leaf stage, emergence of male inflorescence and normal irrigation as control. Fertilizer treatments were considered as subplots including Azetobacter-1, Phosphate Barvar-2 and the combination of Azetobarvar-1 and Phosphate Barvar-2. The results showed that irrigation and fertilizer treatments had significant effect on corn height, stem diameter, ear diameter and ear length, number of rows per ear, number of seeds per row, 1000 seed weight, biological yield, grain yield and harvest index. Most of the studied traits were declined due to irrigation interruption, but the impact of irrigation interruption at emergence of male inflorescence stage was more pronounced on 1000 seed weight, seed number per row, grain yield and harvest index. the combined use of Azetobarvar-1 and Phosphate Barvar-2 enhanced the plant height, number of seeds per row, biological yield and grain yield of corn by about 10.7, 31.2, 10.6 and 33.7 percent compared to the use of Azetobarvar-1 and 18.7, 3 / 17, 16.5 and 11%, respectively, in comparison with Phosphate Barvar-2 under irrigation interruption at the emergence of male inflorescence stage.

In order to study the effect of water deficit and the application of humic and salicylic acid on physiological traits, yield and yield components of corn, an experiment was carried out as a split-plot based on randomized complete blocks design with three replications at the research field of Islamic Azad Universityof Birjand, Iran in 2014. The main factor was irrigation in three levels (supply of 33, 67 and 100% water requirement) and the sub-factor was humic and salicylic acid application in 4 levels (application of humic acid, salicylic acid, humic + salicylic acid and no application). The results of variance analysis showed that irrigation significantly affected traits of physiological, seed yield components and yield but humic acid and salicylic acid application significantly affected chlorophyle index, stomatal conductivity, 1000-seed weight and seed yield. Also, interaction effect of irrigation and humic acid and salicylic acid was no significant on measured traits. Chlorophyle index, stomatal conductivity, ear number per m2, row number per ear, seed number per row, seed number per ear and 1000-seed weight significantly decreased by 15.6, 35.6, 41.2, 14.1, 33.9, 61.8 and 40%, respectively with the decreas of water requirement from 100 to 33%. Seed yield and biological yield in treatment of 100% water requirement supply, had significantly superiority 3.9 and 2.4 times, respectively as compared with treatment of 33% water requirement supply. Chlorophyle index by 7.5, 7.7 and 8.9%, 1000-seed weight by 22.5, 26.6 and 20.7% and seed yield by 26.5, 18.5 and 21.7%, significantly increased with application of humic acid, salicylic acid and humic acid + salicylic acid respectively as compaed with no application of this acids. The results showed that supply of 100% water requirement and independent application of humic acid or salicylic acid can increase seed yield of corn.

To evaluate the effects of salinity, molybdenum and mycorrhizal fungi (Glomus versiform) on corn, a plot experiment was conducted as factorial in a completely randomized design with three replications at the University of Shahrood in 2014.The experimental treatments were three levels of molybdenum 0 ,10 and 20 mg Mo/kg soil, three levels of salinity included: 0, 4 and 8 dS/m and two levels of inoculation and without inoculation with the mycorrhizal fungi (Glomus versiform). The results showed that, the highest activity of catalase was obtained at the 4 ds/m of salinity treatment and 20 mg Mo/kg. Therefore the highest activity of guaiacol peroxidase was in the 8 ds/m salinity treatment and at the presence of mycorrhizal fungi. The interaction between the three treatments of salinity, molybdenum and mycorrhizal fungi had significant effect on the amount of chlorophyll "b", sodium, potassium and molybdenum content in leaves. The highest content of molybdenum in leaves was obtained at the presence of the fungus, the highest level of molybdenum and the 0 salinity treatment. In this experiment, the results showed that, the highest amount of chlorophyll "b" was obtained at the 20 mg Mo/kg , 8 ds/m of salinity and at the the presence of mycorrhizal fungi. As well as the inoculation of mycorrhizal fungi and use of 20 mg Mo/kg caused of increasing potassium and decreasing of sodium absorption corn

Exhaust emissions with changes in metabolical and physiological plant systems causing negative changes in morphological, biochemical and physiological indicators. Previous studies have shown that many of the pollutants in exhaust gases in high concentrations, can causing damage in plants.
In this study, seedlings of corn (Zea mays var. indentata) SC704 variety, after grow, treated time 2, 5 and 10 minutes placed in same situations of temperature, humidity and light in a combustion chamber exposed to the exhaust smoke of gasoline and CNG separately, one group was considered as the control group. The exhaust smoke by interface system was pumping the flow of 5m3/s to a chamber that pots were located within. One month after treatment and random measures on sampling and analysis of the resulting data, the findings showed that stress applied exhaust emissions on all growth parameters, such as length, weight and leaf area and biochemical indices corn plant such as photosynthetic pigments has a negative effect, also exhaust emissions are reduced iron content but increase the absorption and accumulation of heavy metals such as zinc and manganese, the effect of different concentrations of emissions from combustion of conventional gasoline on all growth parameters and biochemical indices of corn more than emissions from the combustion of CNG.

Many studies have been done to identify factors affecting the growth and development of crops such as corn. Considering the special position of maize, determining the effect of these factors is very important. . Since the study of these studies in farms and laboratories is time consuming and costly, the use of artificial neural network is important as a quick and non-destructive way to simulate factors affecting crop production and predict experimental results. The purpose of this study was to assess the predictive power of growth stimulating bacteria on the yield of corn fodder using artificial neural network. After obtaining the required data from experimental studies, Each of the input and output parameters included independent variable(the effect of growth promoting bacteria and effective factors) and dependent variable(forage yield per hectare) data mining were data mining, Then a multilayered perceptron neural network(MLP) with a sigmoid transformation function was designed in the number of neurons 5, 10, 15, 20, 25 in the secret layer. The results showed that the network(MLP) with an error correlation training algorithm with a correlation coefficient(R= 0.999) and mean square error(MSE= 0/000113) With 10 neurons in the hidden layer as the optimum model was able to predict corn forage yield affected by growth-promoting bacteria, Also, in the simulation results with the new input parameters, there was very little difference between the actual output values and the predicted output, Therefore, the artificial neural network in this study has been able to estimate the effect of growth stimulating bacteria on corn, and the resulting neural network can be used to predict other influential factors.

To evaluate the application methods of nitroxin and nitrogen fertilizers on yield and physiological traits of maize (SC 704), a field experiment was carried out in Ahvaz based on a split plot randomized complete block design with three replications during 2013-2014. The treatments included four levels of nitrogen fertilizer (N1:100%, N2: 75%, N3:50%, N4: 25%) pure nitrogen (equivalent to 180 kg per hectare) as the main factor and nitroxin biological fertilizer application method at two levels (seed inoculation B1 and with irrigation water B2) as the secondary factor. The results showed that nitrogen fertilizer significantly increased grain yield and physiological traits. The highest and lowest grain yields were obtained in 75% and 25% nitrogen treatments respectively. The biological fertilizer, nitroxin, had a significant impact on performance, chlorophyll a and b, efficiency, and NAE. The highest grain yield was recorded in B1 (seed treatment). In this study, while method of application of nitroxin showed no significant effect on the traits under study, the combined use of bio-fertilizer with N fertilizer, in addition to producing sufficient crop and improving nitrogen uptake efficiency, could reduce the use of nitrogen fertilizer by 25 percent.

Allelopathy is known as direct or indirect effect of released chemicals in to the environment by a plant species on another one. The effect mostly has harmful for others. Johnson grass is a common weed in corn farm in Isfahan. It has critical impact on growth and development of the crop. On behalf of assessment of allelophatic effect of the weed on seed germination and growth parameters of corn, an experiment was accomplished based on Completely Randomized Design with four treatments by five replications in Agriculture Jahad Education Centre of Isfahan. Factors were extracts of different parts of Sorghum halepense in three type (arial parts, underground parts, whole plant) with five levels of concentrations (25, 50 and 100%). Distilled water considered as control (concentration 0%). Seed corn cultivar single cross-704, used for cultivation. Parameters such as percent and rate of germination, root length, shoot length, fresh and dry weights were measured. Data were analyzed by SAS software through Duncan test. Results showed that germination and growth parameters affected by treatments, showed different results to the concentrations. Results showed that extract had negative effect on all measured parameters except in percentage of germination, as, the most effect showed in concentration of 100 and the lowest in control. Comparison between different parts of the plant showed that underground organs have the most effect on the seedling growth.

In order to investigate the effects of nitrogen levels on grain yield، phyllochron and leaf emergence rate of maize cultivars، a split plot experiment based on randomized complete block design with three replications was conducted at the Research Farm of Islamic Azad University of Ardabil during 2007 cropping. Factors were: nitrogen levels in main plots (0، 80، 160 and 240 Kg N ha-1) and maize cultivars in three levels (SC-301، DC-370 and SC-404) in sub plots. The results showed that phyllochron، time between the appearance of successive leaves on a shoot، was significantly affected by corn، nitrogen levels and interaction of nitrogen levels × maize cultivars. With increased nitrogen levels، the phyllochron was decreased but rate of leaf appearance was increased. Response of maize cultivars was different to these characteristics. Leaf appearance rate in SC-301 was more than SC-404 and DC-370. The highest leaf appearance rate and the least of time for phyllochron was obtained in treatment compounds of SC-301 with application of 240 kg N/ha. Grain yield was significantly as affected by nitrogen levels، cultivar and interaction of cultivar × nitrogen levels. Maximum grain yield was in SC-404 cultivar and minimum of it was in SC-301 cultivar. Means comparisons showed that maximum grain yield was obtained in SC-404 with application of 240 kg N/ ha. However، no significant different was between application of 160 and 240 kg n/ha. Minimum grain yield belonged to SC-301 without application of nitrogen fertilizer. If growth period was limited، it seems that SC-301 with 240 kg N/ha was applied in order to increasing leaf appearance rate and decreasing of phyllochron. However، if growth period wasn’t limited، it would be better to use of SC-404 with application of 240 kg N/ha.

In order to investigate the effects of seed priming with plant growth promoting rhizobacteria (PGPR) on phyllochron and leaf appearance rate of corn, a factorial experiment based on randomized complete block design with three replications was conducted at the Research Farm of University of Mohaghegh Ardabili in 2008. Factors were: three corn cultivars (SC-404, SC-410 and SC-434) and seed priming with plant growth promoting rhizobacteria in four levels (without priming, seed priming with Azosprilium, seed priming with Azetobacter and seed priming with Azosprilium +Azetobacter). The results showed that phyllochron, time between the appearance of successive leaves on a shoot, was significantly affected by corn cultivar, seed priming with plant growth promoting rhizobacteria and interaction between of seed priming and corn cultivars. Seed priming with Azetobacter decreased the phyllochron but increased rate of leaf appearance. Response of corn cultivars was different to these characteristics. Leaf appearance rate in SC-404 was more than SC-410 and SC-434. The highest leaf appearance rate and the least of time for phyllochron was obtained with seed priming of SC-404 cultivar with Azetobacter. Leaf area index was increased due to seed priming with Azetobacter. In all of priming levels, process of variances leaf area index was similar until 37 days after sowing. From 44-65 days after sowing reached to a maximum level (4.96) and then decreased slowly till 79 days after sowing. This might be related to increasing aging of leaves, shadding and competition between plants for light and other resources. The highest leaf area index obtained in treatment combination of seed priming of SC-404 cultivar with Azetobacter and the least of it was in without priming. Number of leaf per plant and leaf dry matter increased in seed priming with Azetobacter. Thus, it is suggested that in order to increase leaf appearance rate, number of leaf per plant and leaf area index, seeds priming of SC-404 cultivar with Azetobacter be applied in conditions of Ardabil Plain.