Effects of Rice Straw Steam-explosion Spent Liquor on the Growth of Cabbage Seedlings

The direct use of spent liquor from pulping and papermaking engineering,which is abundant in active organic matter,can avoid resource wastage and environmental pollution.In this study,the effects of soaking solution and filtrate from steam-exploded rice straw on seed germination and the early development of cabbage were investigated.The results have shown that soaking solution and filtrate stimulated early cabbage growth at low concentrations.Optimal germination potential and the rate of soaking solution-treated cabbage seeds increased by 8％and 5％,respectively;meanwhile,that of the filtrate-treated cabbage seeds increased by 11％and 5％,respectively.Promotion of root growth by steam-exploded rice straw spent liquor was expressed in lateral root multiplication.The fresh weight of cabbage seedlings treated with the soaking solution/filtrate increased by more than 50％and the dry weight over 20％.Comparatively,the stimulation of filtrate on seed germination and early development of cabbage is superior to that of the soaking solution.Steam-exploded rice straw spent liquor is rich in bioactive lignin and oligosaccharides,which makes it a promising biostimulant for promoting crop growth.