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以梭梭和白梭梭一年生盆栽幼苗为试材,测定60%(对照)、40%和20%的土壤相对含水量(SRWC)处理20d后两种梭梭同化枝的电导率和含水量,地上和地下部水势,根部木质素、纤维素、半纤维素含量,根肉质化程度和根长度。结果表明:两种梭梭同化枝含水量随着SRWC的下降均保持较高的水平;SRWC为40%和20%时,两种同化枝电导率的变化不显著,且均保持较低的值;两种梭梭地下部与地上部水势差值随土壤含水量的降低而增大;SRWC为40%的土壤条件促进两种梭梭的根系生长,20%的SRWC条件下仍保持与对照一样的水平;不同SRWC条件下,梭梭和白梭梭根部的木质素、纤维素、半纤维素含量的变化幅度均较小,且保持很高的水平,总含量分别为46·9%～53·3%和50·6%～57·6%。由此推断,在干旱胁迫下两种梭梭的根系依赖于较强的根部输导组织坚韧度,往土壤深层扎根找水,适应干旱环境。
The annual and potted seedlings of Haloxylon ammodendron and Haloxylon ammodendron were used as test materials to measure the electrical conductivity and water content of two kinds of Haloxylon ammodendron after 60 days (control), 40% and 20% soil relative water content (SRWC) Water potential above and below ground, root lignin, cellulose, hemicellulose content, root fleshy degree and root length. The results showed that the water content of the two branches maintained a high level with the decrease of SRWC. When the SRWC was 40% and 20%, the conductivity of the two branches did not change significantly, and both kept low ; The difference between the water potential of the ground and aboveground parts of both Haloxylon ammodendron increased with the decrease of soil water content; 40% SRWC promoted the root growth of both Haloxylon ammodendron and remained the same under 20% SRWC The contents of lignin, cellulose and hemicellulose in the roots of Haloxylon ammodendron and Haloxylon ammodendron were all lower than those of SRWC, and the content of lignin, cellulose and hemicellulose remained at a high level with the total contents of 46.9% -53% · 3% and 50 · 6% -57 · 6%. It is inferred that under drought stress, the root systems of two Haloxylon ammodendron depend on the toughness of the root tissue, which leads to the deep soil to find water and adapt to the drought environment.