Genetic variation of maize responses to low temperatures in the field

Eighteen genetically-diverse maize hybrids (Zea mays, dent lines crossed to a flint inbred-line) were cultivated in the field. Two conditions of cultivation were analyzed: normal sowing and early sowing. Upon early sowing plants grew under lower temperatures than upon normal sowing. Young leaves were harvested for proteomics quantitative analysis after a thermal time (equivalent number of days after emergence at 20°C) of 17 to 18. Three replicates per genotype/condition combination were analyzed. Each replicate was made up of the mix of leaf samples of five different plants.