Fruit development of the diploid kiwifruit, Actinidia chinensis 'Hort16A'

Abstract

BackgroundWith the advent of high throughput genomic tools, it is now possible to undertake detailed molecular studies of individual species outside traditional model organisms. Combined with a good understanding of physiological processes, these tools allow researchers to explore natural diversity, giving a better understanding of biological mechanisms. Here a detailed study of fruit development from anthesis through to fruit senescence is presented for a non-model organism, kiwifruit, Actinidia chinensis ('Hort16A').ResultsConsistent with previous studies, it was found that many aspects of fruit morphology, growth and development are similar to those of the model fruit tomato, except for a striking difference in fruit ripening progression. The early stages of fruit ripening occur as the fruit is still growing, and many ripening events are not associated with autocatalytic ethylene production (historically associated with respiratory climacteric). Autocatalytic ethylene is produced late in the ripening process as the fruit begins to senesce.ConclusionBy aligning A. chinensis fruit development to a phenological scale, this study provides a reference framework for subsequent physiological and genomic studies, and will allow cross comparison across fruit species, leading to a greater understanding of the diversity of fruits found across the plant kingdom.

Fruit Ripening Process in Red Kiwifruit Cultivar &lsquo;Rainbow Red&rsquo; (<i>Actinidia chinensis</i>) on Vines

“…However, invariable firmness remained at approximately 1500 N in the core on October 24. This softening pattern is similar to that of 'Hort16A' kiwifruit (A. chinensis) on vines (Richardson et al, 2011). However, the application of exogenous ethylene rapidly accelerates softening, and core firmness was less than 5 N. This result suggested that the process of fruit firmness reduction differs in an ethylene inductiondependent and an ethylene-independent manner.…”

“…In the kiwifruit variety 'Hort16A', physiological and biological analyses were performed from anthesis (0 DAA) until fruits were senescing on vines (Richardson et al, 2011). Compared with 'Hort16A', the ripening period in 'Rainbow Red' is short.…”

Extension of Shelf-life by Limited Duration of Propylene and 1-MCP Treatments in Three Kiwifruit Cultivars

“…2 and 3). The ability of ethylene/propylene treatment to induce a drastic decrease in firmness before the initiation of autocatalytic ethylene has similarly been observed in 'Hayward' Taglienti et al, 2009;Yin et al, 2008), 'Hort16A' (Richardson et al, 2011), and 'Sanuki Gold' kiwifruit (Mworia et al, 2010(Mworia et al, , 2012. This suggests that kiwifruit exhibits a time lag between fruit softening and ethylene biosynthesis during ripening, unlike most climacteric fruit such as tomato, banana, pear, and avocado, in which softening is synchronized with the induction of endogenous ethylene.…”

“…This signifies that the accumulation of cellular propylene during treatment triggers the kiwifruit softening process without inducing any detectable levels of ethylene, but upon its withdrawal, these softening processes are hampered. Richardson et al (2011) demonstrated that, when 'Hort16A' kiwifruit was treated with ethylene for different durations of 12 h, 24 h, and 36 h, ethylene production was initiated earlier in kiwifruit treated for 36 h (after 1 day) than in fruit treated for 24 h (between 1 and 7 days), and no ethylene production was detected in fruit treated with ethylene for 12 h. Fruit treated with ethylene continuously had a drastic decrease in firmness compared with the case upon short exposure to ethylene for 12 h without the detection of ethylene. In the present study, fruit treated with propylene continuously and for 48 h reached the propylene threshold required to trigger complete fruit softening, whereas exposure to propylene for 12 h or 24 h induced limited softening, probably due to the absence of autocatalytic ethylene.…”

“…'Hayward' kiwifruit with high SSC (14%) and low TA are most readily accepted by consumers (Crisosto and Crisosto, 2001). Previous research has shown that, in 'Hayward' and 'Hort16A' kiwifruit, fruit firmness decreased after ethylene treatment (Crisosto et al, 1997;Richardson et al, 2011;Ritenour et al, 1999). Currently, most of the postharvest protocols for kiwifruit ripening are based on the results obtained from 'Hayward' and 'Hort16A' kiwifruit.…”