Abstract:

To explore the effect of drought stress on the growth of spring wheat at germination stage, the drought resistance indexes were screened. Forty drought-resistant spring wheat strains with two grain colors (red and white) were studied from irrigated and rain-fed area of Ningxia. The effects of PEG-6000 simulating drought stress on radicle length, radicle number, coleoptile length and leaf length were studied. The drought resistance indexes of spring wheat were screened by broad-sense heritability analysis at germination stage. The broad-sense heritability of radicle length was the highest, greater than 0.55, and the control degree of heritability was stable. The heredity of radicle length of red seed in rain-fed area reached 0.95. The broad-sense heritability of coleoptile length of red seed in rain-fed area was the highest, up to 0.94, but its heritability control degree was not stable, and the lowest heritability was only 0.06. The broad-sense heritability of radicle number and leaf length was low and the degree of control was unstable. The broad-sense heritability of radicle length at germination stage of spring wheat was the highest and the control degree was stable. Secondly, it was the coleoptile length, but its control degree of heritability was not stable. Therefore, the length of radicle during germination of spring wheat seeds can be used as drought resistance index to identify drought resistance materials, and the length of coleoptile sheath can be used as the reference.

Key words: spring wheat, germination stage, drought resistance index, irrigated area, rain-fed area, broad-sense heritability