Development of agrobacterium-mediated transient transformation for fruit discs in persimmon (Diospyros kaki thunb.)

Abstract

Fruit quality improvement for fruit trees is an important breeding goal to be achieved through biotechnology. Genes related to fruit quality need to be verified for their function in the fruit itself. Agrobacterium-mediated transient transformation is an effective and convenient approach for gene functional validation in plants. Here, we developed a transient transformation protocol in persimmon (Diospyros kaki Thunb.) fruit discs through the optimization of the genotype and sample method for DkANR functional validation. When the equatorial zone of the fruit disc was 1.0 cm in diameter and 0.2 cm in thickness, RNA interference of DkANR was achieved after 3 days of incubation with the best sampling time at 10-20 WAB (weeks after bloom) when the fruit size reached to 4-7 cm in diameter. GFP (green fluorescent protein) was used as a reporter in developing a transient transformation system, and it was successfully utilized for the RNA interference of DkANR and resulted in an accumulation decrease of proanthocyanidin. In conclusion, an easy and reliable transient guideline for further gene function verification in persimmon fruit is provided through Agrobacterium-mediated transformation system on fruit discs in this research. For fleshy fruits that are produced by perennial woody plants, this useful approach can facilitate the functional validation of fruit quality-related genes.