霸王树的抗盐性研究

Salt Tolerance of Prickly Pear Cactus (Opuntia ficus—indica)

鉴于在干旱区农业中利用盐水资源的需求,我们对霸王树在水培生长中的抗盐性进行了研究。NaCl浓度范围为5(对照)至200molm^(-3)。结果表明,叶状枝的生长对盐敏感,在盐浓度为50molm^(-3)时,生长量为对照的60%。根茎比仅在浓度为200molm^(-3)时才显著降低。对其它不同指标也进行了研究,例如水分含量、Na、K及Cl含量、渗透压和CO_2吸收等。这些指标中,叶状枝水分含量和CO_2吸收的降低均与叶状枝生长降低相联系。含盐量增高使叶状枝渗透压增加,这同组织脱水有关。我们认为霸王树在盐水胁迫下不产生渗透压的调节作用。

In view of the need to exploit saline water resources in agriculture in arid zones, we investigated the salt tolerance of Opuntia ficus-indica in plants growing in solution culture. Salt (NaCl)was added in concentrations ranging from 5 (control )to 200 mol m^(-3). Cladode growth was sensitive to salinity, being 60% of the control at 50 mol m^(-3)NaCl. The root-to -stem ratio decreased significantly only at 200 mol m^(-3). Various other parameters were studied, such as water content, Na,K and Cl content,osmotic pressure,and CO_2 uptake. Of these parameters the decreases in cladode water content and CO_2 uptake were related to the decrease in cladoed growth. Raised salinity increased cladode osmotic pressure, which was associated with tissue dehydration. We concluded that osmotic adjustment does not occur in prickly pear under salt stress.