以抗旱性较强的观赏海棠品种‘王族’和抗旱性较弱的品种‘红丽’幼树为试材,采用"喷施ABA+干旱处理"和"喷水+干旱处理(对照)"2个处理组,测试不同干旱条件下ABA处理的观赏海棠叶片相对含水量(RWC)、相对电导率(REC)、可溶性蛋白含量(SPC) 、可溶性蛋白和脱水素表达情况。结果显示: 与对照相比,ABA处理的 ‘王族’叶片RWC显著升高,REC和SPC显著降低,而‘红丽’的相应指标变化则相反。SDS-PAGE分析表明: ABA处理分别引起了干旱处理过程中‘王族’叶片14.8,18.0,46.2,50.9,78.1,145.2 ku和‘红丽’叶片14.4,18.0,32.8,46.2,89.6,141.0 ku可溶性蛋白的变化。免疫蛋白印迹法测定结果表明: 干旱处理分别诱导‘王族’叶片14.8, 51.0 ku和‘红丽’叶片14.4, 32.8 ku脱水素的积累; ABA处理显著地的诱导2品种叶片干旱处理开始时脱水素的积累,并降低干旱处理7天后‘王族’叶片14.8,51.0 ku和‘红丽’叶片14.4 ku的积累。ABA能够诱导正常水分条件下观赏海棠叶片脱水素的表达,但当植株处于干旱胁迫时,ABA抑制其叶片中被诱导的脱水素的积累,并且此抑制作用与品种间抗旱性呈正相关性。
In order to investigate the effects of ABA treatment on accumulation of the soluble proteins and dehydrins in leaves of ornamental crabapples under soil drought stress, we selected a drought resistance cultivar, Malus spp.cv. ‘Royalty’ and a drought susceptible cultivar,Malus spp.cv. ‘Red Splendor’ as plant materials, ABA solution or water (served as control) was sprayed on leaves of the plants subjected to soil drought. The relative water content (RWC), relative electricity conductivity (REC),soluble protein content(SPC), and the expression of soluble proteins and dehydrins in ornamental crabapples leaves were measured during the drought process. Our results indicated that for M. spp.cv. ‘Royalty’ leaves, pretreated with ABA RWC increased significantly, REC and SPC decreased, while the indices in the ABA-pretreated M. spp.cv. ‘Red Splendor’ leaves changed in the oppositely. SDS-PAGE analysis showed that ABA treatment resulted in the modification of molecule soluble proteins of 14.8, 18.0, 46.2, 50.9, 78.1 and 145.2 ku in ‘Royalty’ leaves and 14.4, 18.0, 32.8, 46.2, 89.6 and 141.0 ku in ‘Red Splendor’ leaves respectively. Immunoblotting results indicated that drought stress induced the expression of dehydrins 14.8 and 51.0 ku in ‘Royalty’ leaves, and 14.4 and 32.8 ku in ‘Red Splendor’ leaves respectively. Moreover, ABA treatment induced significantly these dehydrins accumulation of two cultivars leaves at 0 d of soil drought treatment, and inhibited the dehydrins accumulation of 14.8 ku and 51.0 ku in ‘Royalty’ leaves and 14.4 ku in ‘Red Splendor’ leaves in 7 d after soil drought treatment. In conclusion, ABA treatment was able to induce expression of dehydrins under non-drought conditions in leaves of ornamental crabapples.However, ABA inhibited accumulation of drough-induced dehydrins, when the plants were subjected to drought stress, which had a positive correlation with the drought resistance of different cultivars.