Yield, quality and irrigation water use efficiency of sweet sorghum [Sorghum bicolor (Linn.) Moench] under different land types in arid regions

摘要

In order to evaluate changes in biomass, sugar content, ethanol yield as well as water use status of sweet sorghum [Sorghum biocolor (L.) Moench] a number of experiments conducted in marginal land arid region of Hexi Corridor in northwestern China, with the average rainfall of 116.8 mm, in three land types including loam land, saline-alkaline land and sandy land. The saline-alkaline land and sandy land possessed low total aboveground dry weights of 22.1 and 26.8 t ha -1 in 2009, respectively. In 2010, total soluble sugar yields for saline-alkaline land and sandy land varied from 11.00 to11.28 t ha -1 , which were significantly higher than loam land?s total soluble sugar yield. Similarly, ethanol yield originated from sugar ranged from 6032.57 to 6193.02 L ha -1 for saline-alkaline land and sandy land, respectively, indicating a significant difference in comparison with ethanol yield in loam land. However, irrigation water use efficiency of aboveground biomass in 2009 were 3.93, 3.62 and 2.36 kg m -3 for loam land, saline-alkaline land and sandy land, respectively. The same trend was found in 2010. It is concluded that although loam land produced more biomass yield and irrigation water use efficiency, the higher sugar and ethanol yield of sweet sorghum was acquired in saline-alkaline land and sandy land. Considering the competition of production between food and energy crops, it is pragmatic and meaningful to develop sweet sorghum in saline-alkaline and sandy land. Meanwhile, the soil condition can be improved to adapt different cultivation modes in order to increase biomass yield or water use efficiency in saline-alkaline and sandy lands.