Main content area

Effects of gibberellins A4 on budbreak, antioxidant enzymes’ activity and proline content of flower buds in sweet cherry (Prunus avium)

Cai, Binhua, Wang, Hongxue, Liu, Tianyu, Zhuang, Weibing, Wang, Zhong, Qu, Shenchun, Qin, Yalong
Acta physiologiae plantarum 2019 v.41 no.6 pp. 88
Prunus avium, antioxidant activity, ascorbate peroxidase, budbreak, catalase, cold treatment, dormancy, dormancy breaking, enzyme activity, flower buds, fruit trees, gibberellins, hydrogen cyanamide, hydrogen peroxide, mineral oil, oxidative stress, peroxidase, proline, superoxide dismutase, water treatment, winter
Chilling accumulation is required for deciduous trees to maintain its normal growth and development. However, warm winters appeared more and more frequently, which hindered severely the normal growth and yield of fruit trees. To avoid these problems, artificial dormancy breaking agents are widely used. In our study, the effect of mineral oil, hydrogen cyanamide and gibberellins A₄ (GA₄) on budbreak were evaluated in sweet cherry (Prunus avium), which indicated that GA₄ treatment hastened the date of flower budbreak and increased the percentage of budbreak compared with the other treatments. To better understand the mechanism of GA₄-induced budbreak, the contents of antioxidant enzymes’ activity and proline in sweet cherry flower buds treated with GA₄ and water were evaluated. There was a sharp decrease of catalase (CAT) activity after 5 days of GA₄ treatment and then an increase of CAT activity after 10 days of GA₄ treatment. However, there was a sharp increase of superoxide dismutase (SOD), peroxidase (POD) and ascorbate peroxidase (APX) after 5 days of GA₄ treatment and then a decrease of these enzyme activities after 10 days of GA₄ treatment. There was a transient increase in hydrogen peroxide (H₂O₂) content and proline content after 5 days of GA₄ treatment and a decrease after 10 days of GA₄ treatment. However, there were only small fluctuations after water treatment, which indicated that temporary oxidative stress may contribute to the dormancy release of flower buds in the sweet cherry treated with GA₄ through the regulation of H₂O₂ content coincided with the changes of antioxidant defense system.