关键词: 梨枣, 茎直径微变化, 土壤水势, 信号强度, 水分亏缺

Abstract: We used four-year old pear-jujube（Ziziphus jujuba Mill.）trees grafted on wild jujube[Ziziphus jujuba Mill. var. spinosa（Bunge）Hu ex H. F. Chow]to study the response of parameters derived from trunk diameter fluctuations（TDF）to soil water potential（SWP）. The relationship among these parameters and meteorological factors were also studied to identify suitable indicators for precise irrigation scheduling of pear-jujube. The maximum daily shrinkage（MDS）increased，whereas the daily growth（DG），trunk growth rate（TGR），and maximum daily trunk diameter（MXTD）decreased，as the SWP decreased. The responses of the four indicators to SWP change were significantly（P < 0.05）different. MDS and TGR noise was lower during the stages of water stress development and water stress maintenance，whereas the ratios of signal intensity to noise were higher. MDS and TGR also had significant relationships with potential evapotranspiration（ET₀）and noon vapor pressure deficit（VPD_md），which could indicate atmospheric drought conditions. Therefore，MDS and TGR may provide appropriate indicators for diagnose pear-jujube water content.

Key words: pear-jujube, trunk diameter fluctuation, soil water potential, signal intensity, water stress