水分胁迫对抗旱性不同的荔枝叶片细胞壁H+-ATPase活性的影响

EFFECTS OF WATER STRESS ON CELL WALL H+-ATPase ACTIVITY IN LEAVES OF LITCHI CHINENSIS SONN. WITH DIFFERENT DROUGHT-RESISTANCES

摘要:

以抗旱性较强的荔枝东刘1号和抗旱性较弱的陈紫1－2年分盆栽实生幼苗为试验材料。研究了水分胁迫对荔枝（Litchi chinensis Sonn）叶片细胞胞质以及以离子键和共价键与细胞壁结合的H⁺-ATPase活性的影响。结果表明：（1）叶片相对含水量随水分胁迫程度的增加而减少，抗旱性强的东刘1号下降的幅度小于抗旱性弱的陈紫。（2）H⁺-ATPase在细胞中的分布是：细胞胞质H⁺-ATPase占绝大多数，其次是共价键结合H⁺-ATPase，离子键结合H⁺-ATPase最少，品种间差异不明显。（3）在水分胁迫下，荔枝叶片H⁺-ATPase活性（比活性）均上升，抗旱性强的品种上升的幅度均大于抗旱性弱的品种。

Abstract:

One to 2-year-old seedlings of two lychee (Litchi chinensis Sonn.) cultivars (droughtsensitive Chenzi and drought-resistant Dongliu 1) were planted in pots by moisture stress and normal watering to determine the relative water content (RWC) and the H⁺-ATPase activities in leaves. The effects of water stress on (specific) activity of cytoplasmic, ionically and covalently wall-bound H⁺-ATPase in leaves were studied. The results showed that RWC in leaves decreased with increasing water stress, but such decrease was 1ess in drought-resistant cultivar than in drought-sensitive one． The activities of cytoplasmic， covalently wal1-bound and ionically wall-bound H⁺-ATPase were 81.8O％-83.15％-11.48％-12.3O％ and 5.37％-5.9O％ of the total H⁺-ATPase activity, respectively．No significant difference was observed between two cultivars． Under water stress, the (specific1) activities of cytoplasmic, ionically wall-bound and covalently wall-bound H⁺-ATPase in leaves increased． The extent of increase was higher in drought-resistant cultivar than in drought-sensitive one．