Abstract

Kiwifruits belong to Actinidae family and Actinidia genus which comprises several important varieties from the commercial point of view being the majority of them included in A. deliciosa var. deliciosa and A. chinensis planch. var. chinensis. ‘Hayward’ (A. deliciosa) is a green fleshy kiwi fruit the most commercialized in the world which is characterized for its hexaploid genome (6n = 174). Nowadays there is not much information about kiwi genome and the different ploidy between the kiwi species complicates the sequencing work. Recently has been reported a draft diploid genome of ‘Hong Yang’ (A. chinensis) and the assembled genome reaches a total length of 616.1Mb and contains 39,040 genes. The aim of this study is focused in a transcriptomic approach by RNAseq analyses of ‘Hayward’ kiwifruits treated with Ethrel (ethylene precursor) and 1-MCP (ethylene repressor) in order to identify significative genes related to softening and respiration rate using ‘Hong Yang’ as reference genome. We sequenced eighteen libraries by Illumina HiSeq 2500 platform and we obtained a total of 670.195.682 reads which were trimmed with FLEXBAR software for filtering low quality reads. Filtered sequences were aligned to Actinidia chinensis genome using Bowtie2 software. The alignment results showed around 70.72 % of reads aligned to Actinidia chinensis genome and 29.28 % were not aligned. Finally, 18,036 genes were differentially expressed from a total of 79,614 genes identified. This study has allowed us to identify genes related to the fruit maturation process of the Hayward kiwi variety, which will allow us to create a gene reference framework to focus new trials on other Actinidia species.