REFLECTIVE MULCH IMPROVES FRUIT SIZE AND FLOWER BUD FORMATION OF PEAR CV CLARA FRIJS

M. Bertelsen
‘Extenday’, a reflective film from a New Zealand company, was tested in a 12-year-old experimental pear planting in Denmark in the years 2001-2003. The aim of the experiment was to examine whether benefits in the form of increased fruit size, advanced maturity and improved flower bud formation could be achieved by the use of the film, and to determine if the investment was profitable. The ‘Extenday’ film was tested on the cultivars ‘Clara Frijs’ and ‘Doyenné de Comice’ at two different tree spacings, either 1.5 m x 3.25 m or 2.0 m x 4.0 m. To accommodate this, film of different widths was supplied and tied to the tree trunks with the use of rubber bands, covering app. 90% of the area between tree rows. The film was put in place shortly after bloom and kept on until after harvest. In all years, fruit size was improved in the ‘Extenday’ treatments, or trees carried significantly larger crop loads that reached the same fruit size as the lighter cropping control trees. In 2002, a year of high yields, the peak fruit size of the ‘Extenday’ trees was shifted from 60-65 mm to 65-70 mm. The effect on size was also confirmed by fruit growth measurements that showed an increased daily growth rate. Fruit quality was monitored on a weekly basis during the last month before harvest, but there was no indication that the ‘Extenday’ treatment increased the rate of fruit maturation. On the contrary, fruit firmness, soluble solids content, starch degradation, as well as fruit colour were similar to the control at harvest. Flower bud counts were carried out on 30 ‘Clara Frijs’ trees in the spring of 2003. Trees from the ‘Extenday’ treatment were found to have twice as many flower buds as the control trees despite having carried similar crop loads the year before. Economic calculations show the ‘Extenday’ film to be profitable when used in ‘Clara Frijs’ plantings, especially in years of large crop loads where both fruit size and flower bud formation may be improved. Contrary to this, the ‘Extenday’ was not profitable with ‘Doyenné de Comice’ because this cultivar gives low returns in Denmark.
Bertelsen, M. (2005). REFLECTIVE MULCH IMPROVES FRUIT SIZE AND FLOWER BUD FORMATION OF PEAR CV CLARA FRIJS. Acta Hortic. 671, 87-95
DOI: 10.17660/ActaHortic.2005.671.10
https://doi.org/10.17660/ActaHortic.2005.671.10
Pyrus communis, reflective film, reflective foil, ¿Extenday¿, biennial bearing, fruit quality, fruit size
English

Acta Horticulturae