Identification of genes associated with BA-induced apple fruitlet abscission
Fruit thinning is an essential part of the commercial production of quality apples. Benzyl adenine (BA) is a synthetic cytokinin that has been used for fruit thinning. In order to understand the molecular mechanisms underlying the BA-induced thinning, the suppression subtractive hybridization (SSH) method was used to construct two cDNA libraries that represent potential genes differentially expressed in apple fruitlets 24 h or 72 h after treatment with BA. 350 EST clones were obtained: 192 clones represent transcripts that are preferentially expressed 24 h after the BA treatment, while the other 158 clones are derived from mRNAs of small apple fruits that were treated with BA 72 h previous. Sequence analyses revealed that these clones represent 102 (24 h) and 80 (72 h) unique genes. The largest set of genes is related to carbohydrate and energy metabolism, suggesting that BA treatment is likely to create a temporary carbohydrate deficit or energy starvation in the fruitlets, resulting in apple fruit abscission; this mechanism is very similar to that underlying shade-induced fruitlet abscission in apple. Ethylene-related genes are also among the BA-induced genes. Some of these genes may serve as molecular markers for apple thinning.
Zhou, C., Liu, B., Lakso, A.N., Robinson, T.L. and Gan, S. (2017). Identification of genes associated with BA-induced apple fruitlet abscission. Acta Hortic. 1177, 249-258
apple thinning, benzyl adenine, fruitlet abscission marker genes, Malus domestica, SSH