Flower quality and fruit size in kiwifruit (Actinidia deliciosa)

Abstract

Kiwifruit (Actinidia deliciosa (A. Chev.) C.F. Liang et A.R, Ferguson 'Hayward') vines were grown at five sites that represented the climatic range of the major kiwifruit growing regions of New Zealand. Hydrogen cyanamide was applied to half the vines at three of the sites. Measurements of flower quality over two seasons were used to determine if this was linked to fruit weight at harvest. There was a progressive increase in ovary fresh weight and ovary dry weight from warmer to cooler sites. Hydrogen cyanamide increased ovary fresh weight by between 6 and 20% and fruit weight by up to 11%Corresponding author. H00010 Received 13 April 2000; accepted 30 March 2001at the two warmest sites. Variation in ovary fresh weight and dry weight accounted for some of the variation in fruit weight 170 days from flowering in the first season, but over both seasons, by itself, had no predictive value. The highest correlation between fruit weight and flower quality across both seasons was with the ratio of pedicel length to seed number (r 2 = 0.56). The relatively consistent relationships that have previously been found between crop load and average fruit weight and between flower quality and fruit weight at harvest did not apply over different seasons and regions.

Modifying Carbohydrate Supply to Fruit during Development Changes the Composition and Flavour of Actinidia chinensis var. chinensis ‘Zesy002’ Kiwifruit

“…chinensis and A. eriantha [53]. Cytokinin concentrations were also elevated in 'Zesy002' fruit in this study during early fruit development (15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27)(28)(29) suggesting that cell division in this genotype occurred during the very early stages of kiwifruit growth [54] before treatments were applied. Therefore increases in fruit growth through high carbohydrate source supply to fruit sinks in this study were likely due to increased cell expansion [55].…”

Spatiotemporal Variation in Pollination Deficits in an Insect-Pollinated Dioecious Crop

“…In cases where we obtained negative values for pollination deficit, we considered that these indicate the absence of pollination deficit and were treated as zero in subsequent calculations in this study. Despite our attempts to minimize them, negative values may result from within individual differences (e.g., ovary size, resource allocation, shadow) known to affect fruit weight within plants [ 51 , 52 , 53 ].…”

Sink priority on ‘Hayward’ kiwifruit vines

“…Austin et al (1999) described a similar correlation between early cell division and final fruit size in apple, but they cautioned that this linkage may not be causal. McPherson et al (2001) suggested that fruit size potential of kiwifruit may be determined even earlier in the season, between budbreak and flowering. They attempted to link fruit size at harvest to flower ovary weight at mid bloom.…”

“…The maximum fruit size potential of kiwifruit is believed to be determined early in development, either before flowering (Piller et al 1998;McPherson et al 2001) or during an early stage of cell division (Austin et al 1999). Hall et al (1996) reported that c. 75% of the variation in mean fruit volume at harvest was already determined by 50 days after flowering.…”