NaCl胁迫下营养液栽培嫁接西瓜生长动态及叶片生理生化特性的研究

Studies on growth trends, physiological and biochemical characteristics in hydroponically-grown grafted watermelon under NaCl stress

以日本引进的耐盐品种帝王新土佐南瓜为砧木、京欣二号西瓜品种为接穗,在NaCl胁迫下对营养液栽培嫁接植株与自根植株的生长动态及叶片生理生化特性进行了比较研究。结果表明,嫁接植株在生长前期各形态指标与自根植株差异不明显,但在生长的中期和后期各形态指标均显著高于自根植株;嫁接植株叶片的净光合速率(Pn)、气孔导度(Gs)和胞间CO2浓度(Ci)均显著高于自根植株;嫁接植株叶片超氧化物歧化酶(SOD)活性、过氧化物酶(POD)活性、脯氨酸含量及根系活力均显著高于自根植株,而丙二醛(MDA)含量显著低于自根植株。以上结果表明,在所测定的指标方面西瓜嫁接植株的耐盐性显著强于自根植株。

Using ‘King Shindosa’ pumpkin （Cucurbita maxima× C. moschata ） as root stock, watermelon （Citrullus lanatus （Th） Mansfeld） cultivar ‘Jingxin No. 2’ as scion, grafting was made to compare the differences in plant growth trends, physiological and biochemical characteristics of the leaves between grafted and self-root plants under NaCI stress. The results showed that no obvious differences in morphological indexes were observed between grafted and self-root plants at the early stage of the growth course, however,the morphological indexes of grafted plants were significantly higher than that of self-root plants. Photosynthetic rate （Pn）, stomatal conductance （Gs） and intercellular CO2 concentration （Ci）of grafted plants were significantly higher than that of self-mot plants. The activities of superoxide dismutase （SOD） and peroxidase （POD） , proline content and root vigor of grafted plants were significantly higher than that of self-root plants, while rnalondialdehyde （MDA） content of the former was significantly lower than that of the later. Based on these results, it could be concluded that the tolerance to NaCl stress of grafted watermelon plants was stronger than that of self-root plants.