Avocado Fruit Pulp Transcriptomes in the after-Ripening Process

Liqin Liu,Dengwei Jue,Shengyou Shi,Yicheng Wang,Bo Shu,Yongzan Wei

doi:10.15835/nbha47111346

Abstract

Avocado is an important tropical fruit whose after-ripening process is still poorly understood. The fatty acid, phenolics, flavonoids, and tannins were analyzed in ‘Lisa’ avocado (Persea americana Mill. ‘Lisa’) fruit pulp during after-ripening. The transcriptome was analyzed to screen for transcripts associated with the aforementioned after-ripening parameters. The results showed that there were no significant differences in the total fatty acid content among the preclimacteric, climacteric, and postclimacteric stages. Nevertheless, the concentrations of C18:3 (α-linolenic acid) were significantly higher in the climacteric and postclimacteric stages than the preclimacteric stage. RNAseq generated 235,082 transcripts and 151,545 unigenes. In addition, 4,324 DEGs were produced among the three stages. KEGG analysis of the DEGs suggested the pathways about “α-linolenic acid metabolism, unsaturated fatty acid biosynthesis”, “fatty acid degradation”, “linoleic acid metabolism and fatty acid biosynthesis”, “linoleic acid metabolism and fatty acid elongation”, and “fatty acid elongation” may all contribute to the C18:3 variations in ‘Lisa’ avocado fruit pulp. Several transcription factors, including the ethylene-related transcription factors, such as NAC, MYB, bHLH, and WRKY, were also identified in the DEGs database. This study generated transcript data and screened the transcription factors involved in the avocado after-ripening process. This information could be used to control after-ripening in avocado and maintain fruit quality during storage.

Highlights

Avocado (Persea americana Mill.) is a fruit tree indigenous to tropical- and subtropical regions
The samples were obtained at day 0 (0D), day 3 (3D), and day 6 (6D) after harvest
There were no significant differences in the 0D, 3D, or 6D samples in terms of these indices

Summary

Introduction

Avocado (Persea americana Mill.) is a fruit tree indigenous to tropical- and subtropical regions. Avocado fruit has long been considered a healthful food. Research has shown that it can be useful in the management of hypercholesterolemia and hypertension (Dreher and Davenport, 2013). Consumer demand for avocado has significantly increased in recent years. Avocado trees have been cultivated in the southern Chinese provinces of Guangdong, Guangxi, Hainan, and Yunnan. The area under avocado cultivation has rapidly expanded (Zhang et al, 2015). Postharvest storage is an important aspect of avocado production and has presented some challenges in the production area of China (Zhang et al, 2015). Premature fruit overripening has decreased crop value

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Conclusion