To investigate the effects of different intercropping arrangements on barley and vetch forage yield and to find the land use advantage in the intercropping system, an experiment was carried out based on randomized complete block design with eight treatments and three replications at the Research Farm, Faculty of Agriculture, University of Tabriz in 2009. Treatments were barley and vetch monocrops, additive intercropping respectively barley: vetch in the ratio of 100:15, 100:30 and 100:45 and substitutive intercropping respectively, barley: vetch in the ratio of 2:1, 3:1 and 4:1. The results showed that, the highest amount of dry forage yield is obtained from 100:15 intercropping ratio. The highest intercropping advantage (4.41) was related to 100:15 additive intercropping ratio. Land Equivalent Ratio revealed that in 100:30 ratio, yield was %32 more than monocropping. The highest Relative Yield Total abtained from 100:30 additive intercropping was 1.14. Also, the greatest amount dry forage is 7030kg/ha in 100:15. Based on results of this experiment it can be stated that for the production of hay, additive intercropping method is superior on substitutive intercropping planting and monocroping sowing of barley and vetch.

In order to study of yield and some forage quality traits of mixcropping on rows of oat and vetch, an experiment was conducted based on randomized complete block designed with seven treatments and three replications at the research farm of Agriculture faculty of Shahid Chamran University of Ahvaz in 2014-2015 growing season. Treatments were included different sowing ratios of 100: 0, 70: 30, 60: 40, 50: 50, 40: 60, 30: 70 and 0: 100, respectively, oat and vetch. mixcropping was performed as a replacement method. The evaluated characteristics were included wet and dry forage yield, crude protein yield, percent crude protein, crude fiber, ash, percent soluble carbohydrates, oat and plant height, tiller numbers. The highest forage yield (105. 26 t ha-1), dry (29. 47 t ha-1) and protein yield(2. 27 t ha-1) were obtained from 60 percent of oat and 40 percent vetch sowing ratio. The higher percent of crude protein(17. 49 percent) and the most percent of ash (7. 37 percent) and the lowest percent of crude fiber was obtained in monoculture of vetch. The highest amount of soluble carbohydrates(12. 66 percent) was obtained in 30 percent of oat and 70 percent vetch. The highest land equivalent ratio for wet (1. 26) and dry(1. 60) forage yield and protein yield(1. 50) was obtained, respectively, 50percent and 50percent of oat and vetch and 60percent oat + 40percent vetch. According to the results in this experiment it seems that oat and vetch mixcropping on row in terms of forage quality and quantity, can recommend as an appropriate manner compared to monocultures of the studied species.

In order to investigate the effects of different intercropping ratios of fenugreek and savory on their yield and essential oil, an experiment has been conducted, based on a randomized complete block design (RCBD) with three replications in Ahar Faculty of Agriculture and Natural Resources. The treatments include different row intercropping ratios, 50% savory + 50% fenugreek (1+1), 33% savory + 67% fenugreek (1+2), 67% savory + 33% fenugreek (2+1), 50% savory + 50% fenugreek (2+2), 25% savory + 75% fenugreek (1+3), 75% savory + 25% fenugreek (3+1), and sole cropping fenugreek and savory. The study measures yield, essential oil percentage and essential oil yield of fenugreek and savory, biomass of savory, land equivalent ratio, actual yield loss or gain, relative crowding coefficient, intercropping advantage, competitive ratio, relative value total, and system productivity index. Results reveal that fenugreek yield in sole cropping are significantly higher than other intercropping ratios, with the highest percentage of seed protein of fenugreek and dry weight, essential oil percentage and essential oil yield of savory, obtained in 1 row savory + 1 row fenugreek. The highest fenugreek essential oil yield is achieved in sole cropping and 1 row savory + 3 rows fenugreek. Among the used intercropping treatments, the highest intercropping advantage (IA) (1. 29) belongs to 1 row savory + 3 rows fenugreek, with the maximum land equivalent ratio (LER) values (1. 94) obtained in 1 row savory + 1 row fenugreek, indicating yield improvement in intercropping systems by 94%, as compared with sole cropping. System productivity index in 1 row savory + 1 row fenugreek (1860. 3) has been more than other intercropping treatments. According to the yield and agronomic and economic benefits, it seems that 1 row savory + 1 row fenugreek is suitable for increasing the yield, the income, and land use efficiency.

In order to investigate the effect of different sources of fertilizer and patterns of mixed cultivation of chicory (Cichorium intybus L.) and annual medic (Medicago scutellata) on agromorphological characteristics and forage yield , a factorial experiment was carried out  in a randomized complete block design with three replications at the Behbahan agricultural Research farm, Iran. The first factor was different fertilizer sources (chemical, organic and integrated (in three levels including chemical fertilizer (urea + triple super phosphate), vermi-compost fertilizer and combined fertilizer (50% chemical fertilizer + nitroxin biofertilizer + fertile phosphate 2) and  the second factor was five levels of intercropping patterns including pure cultivation of chicory, pure cultivation of annual medic, one row of chicory: one row of annual medic, one row of chicory: two rows of annual medic and two rows of chicory: one row of annual medic. Studied traits for chicory and medic were plant height, number of sub-branches, number of leaves per plant, chlorophyll index, leaf area index, dried forage yield and advantageous indices of intercropping including land equivalent ratio (LER), actual yield loss (AYL) and intercropping advantage (IA). The results showed that different treatments had significant effects on the studied traits. The maximum dried yield of chicory and annual medic (4 and 4.6 ton.ha-1 , respecyively) obtained in pure cultivation and chemical fertilizer source, which was not significantly different from pure cultivation and vermin-compost and integrated fertilizer sources. Considering the total yield of two crops and land equivalency ratio higher than one, the mixed ratios of chicory-medic replacement with vermin-compost and combined fertilizer sources were beneficial compared to sole cropping of each crop.

Intercropping is considered for increasing and stability of yield per unit. In order to study the effects of different intercropping arrangements on sorghum and mungbean yield and to find the land use advantage in the intercropping system, an experiment was carried out based on a randomized complete block design with seven treatments and three replications at the Research Farm, Faculty of Agriculture, University of Tabriz in 2013. The treatments were as follows: sole cropping of sorghum, sole cropping of mung bean and five intercropping patterns of sorghum: mungbean with replacement ratios ((1: 1), (2: 1), (3: 1), (1: 2), (1: 3)) respectively. The results showed that the maximum grain yield was obtained from both species in monoculture treatment. The highest intercropping advantage (3.22) was related to treatment (1: 3). Also, the highest value of RYT was observed 1.36 in treatment (1: 1). Land equivalent ratio (LER) in all evaluated treatments was more than one. Thus, according to economic evaluation indices, sorghum and mungbean intercropping was economically justified in comparison with their sole cropping in Tabriz.

Objective: For investigation of intercropping of maize and faba bean, an experiment was conducted in Research Station of Agriculture Faculty of Tabriz University during growing season of 2013.Methods: Experimental design was randomized complete block design with three replications and seven treatment. Treatments included one row intercropping (1: 1), 4 strip intercropping pattern with ratios of (1: 2), (1: 3), (2: 1) and (2: 2) maize and faba bean and 2 treatments of faba bean and maize sole culture.Results: Based on results, grain yield and biological yield of two species in sole culture was significantly different from other species and reached their highest level. Evaluation of different patterns of intercropping using Land Equivalent Ratio (LER) showed that strip intercropping with ratio 2: 2 dedicated highest ratio of LER to itself. Regarding to maize as a major yield in all cropping patterns, economic value or Relative Value Total (RVT) was lower than one, but regarding to economic production of faba bean, RVT of all intercropping was more than one, and among them strip intercropping 2: 1 had highest RVT(9.65). Relative Crowding Coefficient (RCC) showed that in treatments which crowding one of two species is more than other, that species is superior competitively.

In order to evaluate the forage yield, crude protein and advantage indices of grass pea-cereal intercropping systems, a field study (2015-2016 and 2016-2017) was conducted as randomized complete block design (RCBD) with 13treatments and three replications at the research station of Faculty of Agriculture, University of Tabriz, Iran. The treatments were sole planting of grass pea, barley, oat and triticale and intercropping grass pea with each of the above cereals (in the flag leaf appearance stage), in three seeding ratios (grass pea: cereal; 25: 100, 50: 100 and 50: 80). The results showed that the highest and lowest forage yield were obtained in 80% grass pea-100% oat (8410 kg. ha-1 ), 80% grass pea-100% barley (8094 kg. ha-1 and grass pea sole crop (4758 kg. ha-1 ), respectively. Also, the highest and lowest crude protein was recorded in grass pea (152 g. kg. DM-1 ) and triticale (77 g. kg. DM-1 ) monocrops, respectively. The land equivalent ratio (LER) value was greater than one in most of intercropped treatments with the exception of grass pea-triticale (50: 100), which indicates advantage of mixtures compared with monocrops. Economic advantage in terms of relative value total (RVT) was greatest in the cases of grass pea mixtures with oat and barley (1. 34 and 1. 24, respectively) at the 50: 80 seeding ratio. Generally, the results of this research showed that the grass pea intercropped with oat and barley at the 50: 80 seeding ratio can be selected as the best legume-cereal intercropping systems due to higher forage yield, crude protein and economic benefit.

Background and Objectives: Intercropping is a valuable cultivation system in the world due to the better use of resources and increase the quantitative and qualitative yield of plants. It also can be considered as one of the approaches to improve yield and stability in production. Recently, medicinal plants intercropped by legumes have been noticed. In order to evaluate faba bean and fennel intercropping advantage under row-replacement and additive series, an experiment was conducted in 2019. Materials and Methods: This experiment was carried out at the research farm of the Azarbaijan Shahid Madani University, Tabriz, Iran, in a randomized complete blocks design with three replications. Treatments including 6: 0, 4: 2, 3: 3, 2: 4, and 0: 6 of faba bean: fennel rows under replacement series and 6: 3, 6: 2, 2: 6, and 3: 6 of faba bean: fennel rows under additive series. After reaching a constant weight of fennel fruits, yield and its components (number of umbels and umbellets and fruits per umbellet, 1000-seed weight, biological yield, seed yield, and harvest index) were measured in fennel plants. The essential oil content in fennel fruits was also measured using a Clevenger apparatus. Faba bean biomass was measured after harvesting plants in the flowering growth stage. Finally, the relative crowding coefficient, land equivalent ratio, actual yield loss or gain and intercropping advantage of faba bean: fennel mixed cultivation were calculated in the row-replacement and additive series. Results: The results showed that intercropping of faba bean and fennel had a significant effect on all studied traits. The highest number of umbels per plant was obtained from sole cropping (12. 10). Also, the highest number of umbellets/umbel was related to intercropping of two rows of faba bean: four rows of fennel and three rows of faba bean: three rows of fennel by 22. 05 and 19. 62, respectively. The highest 1000-seed weight was obtained from sole cropping of fennel (5. 62 g) and replacement intercropping, especially from two rows of faba bean: four rows of fennel (5. 56 g). The highest biological yield (1503. 47 kg/ha) and seed yield (617. 73 kg/ha) were obtained from the sole cropping of fennel. The maximum harvest index was related to the intercropping of three rows of faba bean: three rows of fennel, which shows that such a mixture ratio leads to the highest seed yield rather than biological yield produced. The highest fennel essential oil content was obtained from additive series. The highest faba bean biomass was found in the sole cropping (1933. 02 kg/ha) and the lowest in treatments in which two rows of faba bean has been planted. Two rows of faba bean + six rows of fennel had the highest (3. 96) relative crowding coefficient. The land equivalent ratio in all row-replacement and additive series was more than one or close to one, which indicates the usefulness of faba bean and fennel intercropping. The highest actual yield (0. 07) and intercropping advantage indexes (0. 17) were related to three rows of faba bean + three rows of fennel. Also, the lowest actual yield was related to additive series, especially treatments in which fennel had a higher mixture ratio than faba bean. Conclusion: Based on the results obtained in this study, environmental resources including light, water, and nutrients have been used optimally in the three faba bean rows + three fennel rows and there was no effective competition to achieve them in this row-replacement series. In other words, ecological niche separation in this intercropping system has been done favorably, and subsequently the actual yield index increased. Therefore, the mixture ratio by 50: 50 in the row-replacement series is recommended to achieve the highest benefit in semi-arid conditions where this experiment was conducted.

Background and Objective: The goals of study were to evaluate the competitive and economic indices of Kochia, Sesbania and Guar intercropping to select the best cultivation system in conditions of salinity stress. Materials & Methods: This experiment was performed at the National Salinity Research Center (NSRC) Yazd-Iran in 2016 and 2017. Three replicates of this split-plot experiment was done using randomized complete block design. The main factor was salinity stress at three levels (irrigation with 4, 9 and 14 dS/m electrical conductivity) and sub-factor, cultivation systems (three sole cropping of Kochia, Sesbania and Guar and their two and three species intercropping. Results: The results showed that salinity decreased the height of Sesbania and Guar and the mixed cultivation maintained the height of Guar and reduced leaf temperature. The highest percentage of green cover was at 4 and 9 dS/m in three Species, but at 14 dS/m in Kochia sole cropping which had no significant difference with three species. By increasing the salinity from 4 to 14 dS/m, the leaf chlorophyll index of the Guar decreased 21. 9% and Sesbania 11. 4%, respectively. Intercropping of the three species increased the leaf chlorophyll concentration. The use of mixed cultivation increased the yield of Guar and Sesbania. Conclusion: Due to the four advantage indices and Relative Value Total at the three salinity levels (1. 16, 1. 08 and 1. 01), it is recommended to replace Kochia sole cropping by three species intercropping.