Abstract:
【Objective】 To study the drought resistance at seed germination stage of six Liaomian cotton varieties under PEG simulated drought stress.
【Methods】 The seeds of six Liaomian varieties were used as the testing materials to study drought resistance at seed germination stage under different concentrations of PEG-6000 (0, 2.5%, 5.0%, 7.5% and 10.0%). Germination energy, germination rate, germination index, germination drought resistance index, hypocotyl length, root length, seedling fresh weight and root fresh weight were measured under different drought stress.
【Results】 The germination of cotton seeds was inhibited to different degrees, and the germination energy, germination rate and germination drought resistance index were decreased with the increase of PEG concentrations. Seedling growth index and root growth index were significantly inhibited under 2.5% PEG stress. 5.0% PEG stress promoted root length growth of all materials. The inhibition degrees of each index under PEG stress above 5.0% concentration were gradually increased with the increase of stress.
【Conclusion】 The six Liaomian cotton varieties were sorted according to their drought resistance as follows: Liaomian 10>Liaomian 23>Liaomian 45>Liaomian 53>Liaomian 49>Liaomian 34.