Response of chickpea varieties to drought stress and Ascochyta blight, caused by <i>Ascochyta rabiei</i>

Ascochyta blight, caused by Ascochyta rabiei, is an important constraint to chickpea production globally. Chickpea is often grown in drier areas, prone to drought, especially terminal drought. Drought is a problem for crop cultivation worldwide and as the climate changes, drought risk increases. The extent to which commercial chickpea varieties will respond to drought and how this will impact their susceptibility or resistance to Ascochyta blight under temperate conditions of Saskatchewan is not known. We evaluated the response of chickpea varieties CDC Leader, CDC Orion, CDC Orkney, and CDC Pearl to drought during vegetative growth, followed by ample watering and inoculation with A. rabiei at flowering in some experiments. Greenhouse and growth chambers experiments had randomized complete block designs with five replicates per experiment. Both moderate and severe drought reduced plant height, numbers of nodes, and often biomass. In an initial experiment, drought-exposed CDC Leader developed more severe Ascochyta blight (3.6 versus 2.2 on a 0–9 scale). However, in subsequent experiments, drought did not influence the disease. CDC Orion was more drought-tolerant than CDC Leader. CDC Orkney was less drought-resilient than CDC Leader or CDC Pearl. CDC Pearl exhibited lower disease than CDC Leader, regardless of drought. The scouting for Ascochyta blight in seasons with early-season drought would be beneficial when rain is forecast; however, drought during vegetative growth does not always lead to more severe disease under conducive conditions. Field trials are merited to enhance the utilization of commercial chickpea cultivars.