Abstract: We examined the effects of different mulching practices on soil moisture, water consumption characteristics, tuber yield, and water use efficiency of potato field, by setting up two kinds of whole maize straw strip mulching (ST) and plastic film mulching (PT) in a semiarid area of central Gansu, with bare flat land (CK) as control. The results showed that both mulching practices significantly increased soil water storage in 0-200 cm profile during sowing to harvest stages (P<0.05). Soil water storage peaked during the harvest stage under the ST treatment (12.3%) and during starch accumulation stage under PT treatment (9.1%), respectively. Water consumption of potato under both mulching practices during the whole growing stage was lower than that of CK, with the largest decrease (by 23.4%) under the ST practice. The ST pattern significantly reduced soil water consumption in the early (from sowing to tuber initiation) and later growth stage (from starch accumulation to harvest), while significantly increased soil water consumption in the middle growth stage (from tuber initiation to starch accumulation) andincreased deep soil water storage. By contrast, PT practice mainly reduced soil water consumption in the early and middle growth stage and significantly increased soil water consumption in the later growth stage. ST and PT practices significantly increased tuber yield by 32.4% and 32.9%, and water use efficiency by 73.8% and 48.8%, respectively. In conclusion, the whole maize straw strip mulching can significantly improve soil moisture in 0-200 cm soil layer in the middle and late growth stage of potato, increase soil water consumption in the critical growth stage of potato, and thus significantly improve potato yield and water use efficiency.

Key words: phosphorus, Camellia sinensis, acid rain, nitrogen, tissue differentiation.