Effect of intercropping with barley (Hordeum vulgare L.) on dryland chickpea (Cicer arietinum L.) yield, land use efficiency and weed control

Intercropping is an important strategy for enhancing the sustainability of agriculture in the world by increasing food production and land use per unit area. Intercropping, which is defined as growing two or more species simultaneously in the same field during a growing season, is considered as an important strategy in developing sustainable production systems. In most cases, one of the plants introduced in intercropping is a plant from the legumes family. Chickpea is a plant that plays an important role in sustainable agriculture and soil fertility.

In order to evaluation effect of chickpea-barley intercropping on component yield, grain yield and weed control, an experiment was conducted at the Jahad Keshavarzi Shazand Research Station during 2019-2020 growing season. Experiment was conducted as a randomized complete block design with three replications. Different experimental treatment were: 1- chickpea sole cropping without weeding, 2- chickpea sole cropping with weeding, 3- barley sole cropping (normal weed control by farmers), 4- additive intercropping of 100% chickpea + 15% barley, 5- additive intercropping of 100% chickpea + 30% barley, 6- additive intercropping of 100% chickpea + 45% barley, 7- additive intercropping of 100% chickpea + 60% barley and 8- additive intercropping of 100% chickpea + 75% barley. Intercropping systems was evaluated by using land equivalent ratio (LER) index.

The results showed that most of the evaluated properties were affected by experimental treatments. The highest chickpea biological yield and grain yield (334 and 99 g m-2, respectively) belonged to the chickpea sole cropping with weeding treatment. Also, the highest barley biological yield and grain yield (423 and 195 g m-2, respectively) were obtained in its sole cropping treatment. In intercropping treatments, the highest grain yield of chickpea and barley (94 and 190 g m-2, respectively) were obtained in additive intercropping of 100% chickpea + 15% barley and additive intercropping of 100% chickpea + 75% barley treatments, respectively. Also, intercropping treatments significantly reduced the weed density and total dry weight. Thus, all intercropping treatments had less weed density and biomass in comparison to chickpea sole cropping without weeding. The lowest weed density and biomass (7.3 plant per m2 and 60 g m-2, respectively) belonged to the additive intercropping of 100% chickpea + 75% barley treatment. In addition, in all intercropping treatments, the land equivalent ratio and relative value indices were higher than one, which indicates the usefulness of intercropping.

The results of this study showed that, chickpea-barley intercropping systems decreased chickpea grain yield in comparison with sole cropping with weeding treatment but, in general, in the most of the intercropping treatments, was better than their sole cropping and associated with improving economic yield and land use efficiency. In general, it can be said that chickpea and barley intercropping, while better controlling chickpea weeds, has a higher total yield than sole cropping of both chickpea and barley species and increases land use efficiency.