Track 2-3-2: Impact of Grass and Legumes on Livestock Production, Soil Conservation and the Nitrogen Cycle in Grassland and Forage Ecosystems
Description
Drylands are mainly used for wheat and food legumes production and there is increasing demand to forage crops in these areas. About 2-3 million hectares of arable lands across Iran are left as fallow every year (Alizadeh, 2010) which could be used to suitable forage crops. Considerable variation has been reported in herbage and grain yields of improved vetches (Vicia spp.) under Iranian rainfed conditions. Introduction of annual feed legumes in dryland cropping systems that are dominated by cereals would reduce pest and disease risk and increase sustainable productivity. However, vetch species as monocultures produce low forage yield under cold dryland conditions. Mixtures of annual feed legumes with winter cereals have greater potential for forage production in the rain-fed conditions (Lithourgidis et al., 2006). Pure stands of most feed legumes are damaged during winter in autumn planting under cold dryland conditions and monocultures of feed legumes as spring crop do not provide remarkable results for forage production in highlands (Alizadeh and da Siva, 2013). On the other hand, winter cereals provide high yields in terms of dry weight but they produce forage with low protein and the forage quality of cereal hay is generally lower than that required to meet production goals for many livestock classes (Lawes and Jones, 1971). In legume-cereal mixtures, companion cereals provide structural support for legumes, improve light interception, and facilitate mechanical harvest, meanwhile legumes in mixtures improves the quality of forage (Thompson et al., 1992). Dhima et al. (2007) reported that there was an advantage of intercropping for exploiting the resources of the environment. Other benefits of mixtures include greater uptake of water and nutrients, enhanced weed suppression, and increased soil conservation (Abbas et al., 2001).
The species from both cereals and legumes which are used in mixtures have different competitions and interaction level. Anil et al. (1998) reported that triticale can be used as an alternative cereal for mixtures with common vetch. Lithourgidis et al. (2006) reported that the mixture of common vetch with oat at the 65:35 seeding ratio gave the highest forage yield. Despite the fact that competition is one of the factors that can affect forage yield and quality there are no reports on the effect of different cereals and different seeding rates on the growth rate of legume–cereal mixtures. Competition can also have a significant effect on growth rate of the different species used in mixtures (Lithourgidis et al., 2006). This differences in seeding ratios could have been because of the species of grass and legume in the mix cropping as well as different soil properties and climatic conditions in the research regions. Alizadeh and da Silva (2013) reported that autumn seeding of smooth vetch (cv. Maragheh) and barley (cv. Abidar) in 1:1 ratio produces considerable forage in terms of quantity and quality. The objective of the present work was to evaluate biomass yield and protein content in some mixtures of barley with smooth vetch at different seed rates along with pure stands under cold dryland conditions.
Included in
Mix Cropping of Smooth Vetch and Barley under Cold Rainfed Conditions
Drylands are mainly used for wheat and food legumes production and there is increasing demand to forage crops in these areas. About 2-3 million hectares of arable lands across Iran are left as fallow every year (Alizadeh, 2010) which could be used to suitable forage crops. Considerable variation has been reported in herbage and grain yields of improved vetches (Vicia spp.) under Iranian rainfed conditions. Introduction of annual feed legumes in dryland cropping systems that are dominated by cereals would reduce pest and disease risk and increase sustainable productivity. However, vetch species as monocultures produce low forage yield under cold dryland conditions. Mixtures of annual feed legumes with winter cereals have greater potential for forage production in the rain-fed conditions (Lithourgidis et al., 2006). Pure stands of most feed legumes are damaged during winter in autumn planting under cold dryland conditions and monocultures of feed legumes as spring crop do not provide remarkable results for forage production in highlands (Alizadeh and da Siva, 2013). On the other hand, winter cereals provide high yields in terms of dry weight but they produce forage with low protein and the forage quality of cereal hay is generally lower than that required to meet production goals for many livestock classes (Lawes and Jones, 1971). In legume-cereal mixtures, companion cereals provide structural support for legumes, improve light interception, and facilitate mechanical harvest, meanwhile legumes in mixtures improves the quality of forage (Thompson et al., 1992). Dhima et al. (2007) reported that there was an advantage of intercropping for exploiting the resources of the environment. Other benefits of mixtures include greater uptake of water and nutrients, enhanced weed suppression, and increased soil conservation (Abbas et al., 2001).
The species from both cereals and legumes which are used in mixtures have different competitions and interaction level. Anil et al. (1998) reported that triticale can be used as an alternative cereal for mixtures with common vetch. Lithourgidis et al. (2006) reported that the mixture of common vetch with oat at the 65:35 seeding ratio gave the highest forage yield. Despite the fact that competition is one of the factors that can affect forage yield and quality there are no reports on the effect of different cereals and different seeding rates on the growth rate of legume–cereal mixtures. Competition can also have a significant effect on growth rate of the different species used in mixtures (Lithourgidis et al., 2006). This differences in seeding ratios could have been because of the species of grass and legume in the mix cropping as well as different soil properties and climatic conditions in the research regions. Alizadeh and da Silva (2013) reported that autumn seeding of smooth vetch (cv. Maragheh) and barley (cv. Abidar) in 1:1 ratio produces considerable forage in terms of quantity and quality. The objective of the present work was to evaluate biomass yield and protein content in some mixtures of barley with smooth vetch at different seed rates along with pure stands under cold dryland conditions.
