Abstract: This research explored the effect of a range of different fertilizer regimes on crop performance of the sweet sorghum variety ‘Xin Gaoliang No.3’ under long-term continuous cropping in the arid region of Xinjiang Province. The experiment comprised eight fertilizer treatments designated CK (control), NK, NP, PK, NPK, M (organic manure fertilizer), NPKM and 1.5NPKM. The traits monitored for ‘Xin Gaoliang No.3’ included plant height, stem diameter, leaf number, brix sugar level, chlorophyll content and yield, among others. The different fertilizer treatments significantly affected a majority of agronomic traits. In general, trends in the different measures (plant height, stem diameter, leaf number, sugar brix content and chlorophyll content) were basically the same for any given fertilizer treatment as the crop developed, but there were differences between the different treatments. At crop maturity, the plant height, stem diameter and brix sugar content were 224.33 cm, 21.47 mm and 18.41%, respectively, for the NPKM fertilizer treatment and these values were significantly higher than those of all other treatments and, respectively, 13.86%, 39.60% and 23.47% greater than in the CK treatment. Fertilization enhanced brix sugar levels in the stem. The stem brix sugar value peaked (18.57%) on the 28th day after mean heading date. but the accumulation patterns brix sugar at different stem nodes from the heading to the maturity differed between fertilization treatments. The pattern of change in chlorophyll content with crop development was basically a constant gradual increase, which peaked at 44.62 SPAD units for the NPKM treatment. The straw yield, grain yield and biomass yield for all fertilizer treatments were significantly higher than those for CK. The straw yield, grain yield and biomass values for the NPKM treatment were 90.80, 4.01 and 94.81 t·ha^-1, respectively, and were the highest among all the treatments. Fertilizer application is beneficial to increase the yield, brix sugar and economic benefit of sweet sorghum. To improve the sustainability of a continuous sweet sorghum cropping system, the choice of fertilizer should be considered. In general, mixed application of organic and inorganic fertilizers (NPKM) is the best fertilizer regime to enhance sustainability of continuous sweet sorghum cropping system in the arid regions of Xinjiang Province.

Key words: sweet sorghum, continuous cropping, fertilization, agronomic traits, yield