Assessing the effect of artificial shading and saccharose sprays on the yield and fruit quality of cranberry (Vaccinium macrocarpon Aiton)

ABSTRACT

A natural low fruit set is reported in cranberry. It is hypothesised that a carbohydrate shortage limits fruit set, and thus yield potential. We aimed to evaluate the effect of carbohydrate availability induced by shade and saccharose spraying during reproductive stages of ‘Stevens’ cranberry to identify critical periods for yield and juice quality (soluble solids, acidity, and colour). Two independent experiments were conducted. On five separate dates, artificial shade (90% shade nets) was imposed for two weeks. On the same dates, 417 kg ha⁻¹ of saccharose was sprayed as a 10% w/v solution. Results showed that shading from full bloom to the beginning of the fruit set reduced fruit number and juice colour. In contrast, 10% saccharose spray increased yield by 22% compared to the control without compromising juice quality. Therefore, the period between the end of full bloom and the beginning of fruit growth is the most critical stage for ‘Stevens’ cranberry.

KEYWORDS:

• Critical period
• non-structural carbohydrates
• bloom period
• flower development
• carbohydrate availability

Acknowledgements

We thank and remember Dr. Nicolás Franck who was an important part of this work. Nicolás died at a young age on October 20, 2017.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

The datasets generated for this study are available on request to the corresponding author.