Germination and coleoptile growth of nine seed lots of maize (representing seven cultivars) were studied at 25#xB0;C (constant), 13#xB0;C (constant) and also at 7#xB0;C (7 days) followed by 25#xB0;C. Relative germination response to sub-optimal temperatures reflected relative differences in germination rate at 25#xB0;C. Exposure to 7#xB0;C before incubation at 25#xB0;C had a marked stimulatory effect on germination of cold- resistant cultivars at the higher temperature. Low temperature appeared to have a differential effect on germination rate and coleoptile growth. Differences in the magnitude of respiration rate did not relate to differences in low temperature susceptibility but kernels of cold-resistant cultivars failed to exhibit a typical respiratory lag phase.
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