Soil Temperature and Physiological Response of Cotton to Alternate Partial Root-Zone Furrow Irrigation in the Oasis Field of Northwest China

The shortage of water resource severely affect the sustainability of the agricultural systems in the arid regions of China. Enhancing water use efficiency of irrigated agriculture is a high priority for agricultural improvement in China. Alternate Partial Root-zone Furrow irrigation (AFI) has been proved to be an effective water-saving irrigation method in the oasis field of northwest China, whereas the responses of soil temperature to AFI was seldomly studied. In this study, the field experiment was carried out in 2007 at Xuebai Experimental Station of Minqin Agricultural Extension Center of Gansu to study the changes of soil temperature as well as physiological responses of cotton to different irrigation regimes, i.e. alternate partial root-zone furrow irrigation (AFI, neighboring two furrows alternatively watered) and conventional furrow irrigation (CFI, all furrows watered) under plastic film mulching with the same irrigation level (24 mm for each irrigation). Results indicated that the differences of soil temperature of two neighboring furrows in AFI were significant (P n /T s (the ratio of average soil temperature of north furrows and south furrows) and SWC w /SWC d (the ratio of average SWC of irrigated furrows and the drying ones) (R 2 =0.703, P<0.01); The WUE-A/WUE-C(the ratios of WUE of AFI and CFI) were more than 1.0 in the first few days after irrigation, whereas at the end of the irrigation cycle, the value declined to be the lowest (0.75); There was no significant difference for the seed cotton yield of AFI and CFI, whereas the percentages of pre-frost seed cotton of AFI was significant higher than that of CFI (P<0.05). This study could provide valuable data for the implement of AFI in the oasis field of northwest China.