Management of ascochyta blight (Ascochyta rabiei (Pass.) Labrouse) using chickpea-based mixed cropping systems through different combinations of companion crops

Abstract

The companion cropping system is practiced in many countries and has several advantages including minimizing the destructive effects of diseases. This work aimed to investigate the effects of a mixed cropping system to manage chickpea blight severity caused by Ascochyta rabiei (Pass.) Labrouse. Chickpea plants were intercropped, in a 3 × 1 system, with wheat, faba bean, and oilseed rape in a field experiment conducted in a randomized complete block design (RCBD) with three replications. The results exhibited that these combinations of companion crops with chickpeas have a significant effect on the incidence of chickpea blight caused by A. rabiei. Compared with the control treatment (mono-crop), the combinations displayed lesser disease severities in which the lowest degree of infection was with combinations of chickpea with faba bean (1.47) followed by chickpea with oilseed rape (1.60) and then chickpea with wheat (1.98) on the 1-5 evaluation scale, achieving the disease reductions by 46.2, 41.4, and 27.5 %, respectively. However, this intercropping system didn’t have significant effects on the percentage of pod infection and the weight of 100 seeds. Intercropping chickpeas with companion crops showed that both oilseed rape and faba bean didn’t have any effects on the seed yield. However, wheat as a companion crop with chickpeas decreased the chickpea yield. It can be concluded, that the application of companion crops can play a physical barrier to prevent the further spread of diseases that are disseminated by air or water splash to the plant vicinity. Nevertheless, some combinations may compromise crop’s yield.