Methods were developed to quantify variation in the fruit, nut and kernel traits using the fruits from four trees of Irvingia gabonensis, an indigenous fruit tree of west and central Africa. The measurement of 18 characteristics of 16–32 fruits per tree identified significant variation in fruit, nut and kernel size and weight, and flesh depth. Differences were also identified in shell weight and brittleness, fruit taste, fibrosity and flesh colour. Relationships between fruit size and weight with nut and kernel size and weight were found to be very weak, indicating that it is not possible to accurately predict the traits of the commercially-important kernel from fruit traits. Seven key qualitative traits are recommended for future assessments of the levels of genetic variation in fruits and kernels. These traits describe ideotypes for fresh fruit and kernel production.
Tag: mango
Metabolomic and transcriptomic analyses reveal new insights into the role of abscisic acid in modulating mango fruit ripening
Mango (Mangifera indica L.) is a climacteric tropical fruit consumed around the world. Although ethylene and abscisic acid (ABA) have been considered to be stimulators that trigger mango fruit ripening, their regulation mechanisms in modulating mango fruit ripening remain uncertain. In this study, we performed integrative analyses of metabolome and transcriptome data combined with a series of physiology and experiment analysis on ‘Keitt’ mango, and we characterized changes in specific metabolite accumulation at different stages during mango fruit development and ripening, which were strongly correlated with transcriptional changes and embodied the physiological changes as well as taste formation. Specifically, we found that ABA, rather than ethylene, was highly associated with mango ripening, and exogenous ABA application promoted mango fruit ripening. Transcriptomic analysis identified diverse ripening-related genes involved in sugar and carotenoid biosynthesis and softening-related metabolic processes. Furthermore, networks of ABA and ripening-related genes (such as MiHY5, MiGBF4, MiABI5 and MibZIP9) were constructed, and the direct regulation of the key ABA responsive transcription factor MiHY5 to ripening-related genes were experimentally confirmed by ranges of evidence. Taken together, our results indicate that ABA plays a key role in directly modulating mango fruit ripening through MiHY5, suggesting the need for a re-conceiving about how we understand ABA function in modulating climacteric fruit ripening.