Abstract:
Sweet sorghum has become one of the important crops for sustainable development of agriculture in drought and saline areas.In a desert oasis area with water shortage and poor land of Hexi Corridor,we planted sweet sorghum in different soils with varied irrigation amounts to figure out the feasible soil and irrigation measures for the area.The study area was located at the edge of Heihe River.Five soils (sandy-loam soil,S1 and S2; sandy soil,S3,S4; loam-sandy soil,S5) and 3 irrigation measures (28.6% water-saving irrigation,I1; 14.3% water-saving irrigation,I2; conventional full-irrigation,I3) were implemented by a field experiment to investigate the effects of water-saving irrigation on the growth characteristics of sweet sorghum and irrigation water productivity under different soil conditions.The results showed that the growth,yield and irrigation water productivity of sweet sorghum with I3 treatment were significantly reduced than those of I1 and I2 treatments; while the stalk biomass with I1 and I2 treatments increased by 7.81% and 3.57%,and the total biomass increased by 6.30% and 3.17%,respectively.The irrigation water productivity with I1 and I2 treatments was 3.63 kg·m
-3 and 2.94 kg·m
-3,48.8% and 20.4% higher than 2.44 kg·m
-3 of I3,respectively.Full-irrigation could not increase sweet sorghum yield,but significantly reduced irrigation water productivity.Except for the stem juice brix,other growth characteristics of sweet sorghum and irrigation water productivity were in an order of S1> S5 > S2 > S4 > S3.Sweet sorghum was suitable for planting in sandy-loam soil or loamy-sand soil,and reasonable water stress would be conducive to the sugar content accumulation and biomass increase in sweet sorghum.