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% at 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 (r² = 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.

Keywords:

• Actinidia deliciosa
• kiwifruit
• flower quality
• fruit size
• fruit growth
• hydrogen cyanamide

Notes

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