Response to Selection for Drought Tolerance in Algerian Maize Populations for Spanish Conditions

Drought is the main stress on maize, and, in order to improve drought tolerance, a breeding program for reduced anthesis-silking interval (ASI) was carried out in Algiers. The objective of this study was to investigate if the selection for reduced ASI made in Algiers had a positive effect on drought tolerance in northern Spain. Two populations selected for reduced ASI in Algiers were evaluated in Algiers and Pontevedra (northwestern Spain) under well-watered and drought conditions. The dry trial was not irrigated, while the well-watered trial was irrigated three times. Data were taken on agronomic and photosynthetic traits in the selection of reduced ASI and anthesis and increased yield for BTM and LOM. In the combined analyses of variance in locations, differences were significant among environments and among genotypes for most agronomic traits. Rank correlations between Algiers and Pontevedra were high and significant for flowering and correlations were higher when measured under the same water regime. In the Spanish environments, differences between the drought and well-watered selection and differences among genotypes within water regimens were significant for most agronomic traits. The agronomic performance of the selection cycles under drought and well-watered conditions indicated that selection for reducing ASI in Algiers was partially effective in Pontevedra. Photosynthetic traits did not respond to selection for ASI; nevertheless, stomatal conductance had positive effects and water use efficiency had a negative effect on plant height and yield. Therefore, base breeding populations after prebreeding in arid environments could be used for breeding programs in humid environments, and some physiological traits had limited effects on plant growth and yield.