Effect of Eucalyptus Bark on the Germination of Pakchoi Seeds

Key words: 
• Eucalyptus bark /
• Pakchoi /
• seed germination /
• seedling growth

Abstract: Eucalyptus bark is a common organic waste and should be treated when used as substrate. Seed germination experiment is one of the typical toxicological experiments for higher plants and can be used to test the toxicity of eucalyptus bark. In this context eucalyptus barks were treated with water, alkali or composting（naturally well composting） and were used as germination substrates to culture Pakchoi with the soil substrate as the control to observe the effect of the eucalyptus bark treatments on the germination of Pakchoi seeds. The results showed that the eucalyptus barks treated with water or alkali suppressed the seed germination of Pakchoi, whereas the naturally well-composted eucalyptus barks did not inhibit the seed germination of Pakchoi. The Pakchoi seeds cultured on the naturally well-composted barks were not significantly different in germination rate and germination potential from the control, and the Pakchoi had a seed germination index of ＞80%, and increased its plant height, root length, and fresh weight by 26.9%,26.57% and 89.36%, respectively. The correlation analysis showed that the seed germination of Pakchoi was mainly affected by total nitrogen, available nitrogen, available potassium and C/N.This indicates that the naturally well-composted eucalyptus barks can be used for development and utilization.