摘要
盆栽条件下,当土壤含水量逐步下降时;①植物的水饱和亏缺加剧,但不同植物间仍有差别;②植物水势趋于下降,其中旱生植物梭梭变幅最大,水势最低;③各植物的蒸腾强度均呈下降趋势,但旱生植物的蒸腾低于中生植物。在充分供水条件下,旱生植物苗木的生物量均大于中生植物,但梭梭例外,说明旱生植物苗木并非真正喜旱。对上述植物抗旱性的主分量分析(PCA)表明,其抗旱性从强到弱的顺序为:梭梭>山川柽柳>多枝柽柳>乔木状沙拐枣>头状沙拐枣>红果沙拐枣>沙枣>箭杆杨。并在二维主分量坐标上可将其分为三类。旱生植物苗木的主要抗旱途径为生理性抗旱,首先是有效的吸水能力,其次是完善的保水机制。
Water relations and drought resistanca of several xerophytes were comparatively studied under potted condition in this paper. Following indexes,e. g, water potential, bound water/free water ratio, water holding capacity, relative water content, transpiratory rate, stoma density, cuticle thickness, biomass etc. were measured and discussed while soil water content was controlled. The results indicated that with the decrease of soil water content, ① plants' water saturation deficit, water holding capacity, bound water/free water ratio went up;②their transpiratory rate and water potential became down. However,under the favorable soil water content xerophytes'biomass was larger than mesophytes'.The drought resistance by principal component analysis, from strongness to weakness, was following: Haloxylon ammondendon→Tamarix arcenthoides→T. ramosissima→Calligonum arborescens→C. caput-medusae→C. rubicundum→Elaegnus angustifolia→Populus nigra.
出处
《干旱区研究》
CSCD
北大核心
1992年第4期31-38,共8页
Arid Zone Research
关键词
旱生植物
盆栽
水分
抗旱性
Water relations
Drought resistance
Xerophyte
