化感作用研究中渗透势对生物测定结果的影响

Influence of osmotic potential on allelopathy bioassa

在不同渗透势的甘露醇溶液培养条件下研究了厚壳桂等对萝卜、黄瓜和白菜化感作用的影响试验结果表明,随渗透势的升高,萝卜幼苗根长和苗高逐渐降低,黄瓜幼苗受抑更明显,而白菜影响极小,未达显著水平。对厚壳桂、锥木和藜蒴的生化他感作用研究中分别以蒸馏水和相同渗透势的甘露醇溶液为对照,其结果化感作用程度普遍降低,有些还发生赁变(化感作用在显著与不显著间转换),故化感生物测定分析中应注意渗透势的影响,以保证结果正确性。

The influence of osmotic effects of aqueous plant extract and mannitol solutions on the results of allelopathy bio-assay was investigated for three crops including radish,cucumber and Chinese cabbage . The results show that with the elevation of osmotic potential,the root length and seedling height of radish and cucumber decrease gradually,while the influence on the growth of Chinese cabbage is not obvious. The results differ when data from deionised water and mannitol solutions with the same osmotic potential are used respectively during the investigation of three main dominant species such as Cryptocarya chinensis . Castanopsis chinesis and Castanopsis fissa . It is found that allelopathic effects are substantially overestimated when osmotic effects are not taken into account. It is concluded that bioassays using aqueous plant extract are more realistic when osmotically adjusted control values are used.