Screening maize (Zea mays L.) hybrids for salt stress tolerance at germination stage

Abstract

Plant breeding may provide a relatively cost effective short-term solution to the salinity problem by producing cultivars that are able to remain productive at low to moderate levels of salinity. To determine the most tolerant hybrid to salinity stress, an experiment was performed as factorial form under completely randomized design (CRD) with three replications. Hybrid factor consisted of fifteen hybrids and five levels of stress (0, -0.3, -0.6, -0.9 and -1.2 MPa). Results indicated that significant decrease was observed in germination percentage, germination rate, root length, shoot length, seedling length and seed vigour traits in stress conditions. Hybrid K166B×K47/2-2-21-2-1-1-1 showed the highest germination percentage, root length, shoot length, seedling length and seed vigour traits in salinity conditions. Results of cluster analysis using the data for all measured traits under different levels of salinity stress (Ward’s minimum variance method) showed clustered hybrids in three groups; Hybrid K166B×K47/2-2-21-2-1-1-1 in the third cluster, hybrids K18×K47/2-2-21-2-1-1-1 and K3651/1×K166A in the second cluster, and twelve other hybrids were in the first cluster. Hybrid K166B×K47/2-2-21-2-1-1-1 was found to be tolerant, while hybrids of the first cluster were sensitive to salt.

Key words: Cluster analysis, germination indices, maize, NaCl stress.