Mohammad Zamanian; Farid Golzardi; Ali Mahrokh; Farhad Azizi; Masoud Torabi; Vida Ghotbi; Mohammad ali Mofidian; Vahid Rahjoo; Elias Soltani
Abstract
The present study is conducted to separate the effective and influential management factors in the production of clover forage in Iran and to identify its limiting factors. In this study, the data obtained from 68 research projects conducted by the Agricultural Research, Education, and Extension Organization ...
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The present study is conducted to separate the effective and influential management factors in the production of clover forage in Iran and to identify its limiting factors. In this study, the data obtained from 68 research projects conducted by the Agricultural Research, Education, and Extension Organization (AREEO) throughout the country during the 2009-2020 years have been analyzed, using the meta-analysis method. The results show that planting date -3.31%, planting method -22.82%, species +40.14%, seeding rate (planting density) +1.53%, drought stress -16.16 %, and phenological stage of forage harvesting -15.42% justify the amount of forage clover variation. Thus, fall planting in the middle of September, basin planting method, choosing the Berseem clover species (Trifolium alexandrinum var. Karaj), the seeding rate of 15-20 kg ha-1 (for forage production), and forage harvesting at the phenological stage of 10-25% flowering, are the most important management and agronomic factors in increasing clover forage production in cold and temperate regions, and not complying with one or a set of these factors will reduce the clover production and will cause yield gap. Overall, the species, planting method, and drought stress are respectively recognized as the most important factors affecting clover forage yield in Iran.
Farhad Azizi; Ali Mahrokh; Vida Ghotbi; Farid Golzardi; Seyed Mohammad Ali Mofidian; Mohammad Zamanian; Vahid Rahjoo; Masoud Torabi; Elias Soltani
Abstract
To identify the limiting factors in forage maize production in Iran, this study has been carried out in order to separate the effective and influential management factors in forage maize production in the country with data. It is obtained from 43 final reports or their derived extracted articles in Agricultural ...
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To identify the limiting factors in forage maize production in Iran, this study has been carried out in order to separate the effective and influential management factors in forage maize production in the country with data. It is obtained from 43 final reports or their derived extracted articles in Agricultural Research, Education and Extension Organization (AREEO) with meta-analysis method. According to the results, plant density (5.65%), drought stress (-13.44%), cultivar (0.31%), planting date (2.54%), and nitrogen fertilizer (24%) justify the amount of forage maize variation. Based on the results of this study, forage yield has increased by about 9.49%, increasing plant density between 80 to 100 thousand plants per hectare. Maize forage yield has decreased significantly under mild stress, severe stress, and very severe drought stress by 25.30%, 14.38% and 8.99%, respectively. Also, for different cultivars and different groups of maturity, group-700 has had a significant increase of 3.83% compared to other groups. For the planting dates of forage maize compared to the control, which is the first half of June, a decrease in forage yield is observed. Finally, the highest percentage of increase in maize forage yield has been obtained from the use of 450 kg ha-1 of urea fertilizer. Overall, nitrogen fertilizer, drought stress, and planting density are recognized as the most important factors affecting corn forage yield in Iran, respectively.
Ali Mahrokh; Farid Golzardi; Farhad Azizi; seid mohammad ali mofidian; Mohammad Zamanian; Vahid Rahjoo; Masoud Torabi; Elias soltani
Abstract
To identify the limiting factors in grain maize production in Iran, a study has been carried out to particulate effective and influential management factors of this crop’s production in the country. The data come from 95 final reports or extracted articles in Agricultural Research, Education, and ...
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To identify the limiting factors in grain maize production in Iran, a study has been carried out to particulate effective and influential management factors of this crop’s production in the country. The data come from 95 final reports or extracted articles in Agricultural Research, Education, and Extension Organization (AREEO), undergoing meta-analysis. Based on this study, of all grain maize variation, 2.93% is justified by plant density, 6.81% by planting structure, 11.12% by planting rotation, 2.28% by conservation agriculture, 25.28% by drought stress, 4.99% by cultivar, 4.46% by planting date, and 25.84% by nitrogen fertilizer. Accordingly, 100 thousand plants per hectare, zigzag double rows planting structure, maize-leguminous crops planting pattern, cultivating in residue, optimum irrigation without drought stress (in case of water availability), 700 maturity group cultivar (in case of adequate growing season), planting in May and early August in temperate and tropical climate, and using maximum 100-300 kg urea fertilizer per hectare are recommended to decrease yield gap in grain maize production.
Farhad Azizi; Ali Mahrokh
Abstract
In order to comparison and determination of the best drought tolerance indices in sweet corn hybrids, an experiment was conducted using a randomized complete block design in split plot lay out with three replications at Seed and Plant Improvement Institute in Karaj in 2006. Three irrigation levels (irrigation ...
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In order to comparison and determination of the best drought tolerance indices in sweet corn hybrids, an experiment was conducted using a randomized complete block design in split plot lay out with three replications at Seed and Plant Improvement Institute in Karaj in 2006. Three irrigation levels (irrigation after 75 as control, 100 and 125 millimeters cumulative evaporation from class A evaporation pan) were assigned as main plots and 12 sweet corn hybrids include KSC403su, Chase, Esquire, Rival, Reveille, Diva, Shimmer, Shaker, PS107, Golda, Royalty and Rana were considered as sub plots. Mean Productivity (MP), Tolerance Index (TOL), Geometric Mean Productivity (GMP), Stress Susceptibility Index (SSI), Stress Tolerance Index (STI) were used to evaluate tolerance or sensitivity to drought stress of the hybrids. STI and GMP indices had a positive and significant correlation with grain yield in non-stress and stress conditions (mild and severe stress treatments). STI and GMP indices showed that Hybrids Diva and Golda had optimum yield in non-stress condition but their yield decreased in severe stress condition. Hybrids KSC403su, Esquire, Shimmer and Shaker had low yield in non-stress but they had suitable yield in severe stress condition. Hybrids Chase, Rival and Reveille had low yield in non-stress and severe stress conditions. Hybrids PS107, Royalty and Rana had optimum yield in both non-stress and stress condition. Therefore, they can be recommended to use in stress and optimum conditions.