Physiological basis of pear pruning and light effects on fruit quality

S. Musacchi
The main trend in European orchard design today is to increase planting density. High density planting (HDP) in pear is expanding due to the widespread use of quince rootstocks to reduce tree size and induce early bearing. These factors have enabled growers to develop orchard training systems for planting densities ranging from 1,000 up to 12,000 trees ha‑1. For densities ranging from 2,000 and 3,000 trees ha‑1, the main quince stock is BA29, and the new Sydo®. New dwarf quince stocks with vigour similar or slightly higher compared to quince C, are the East Malling selections, QR193-16, marketed as MH, and Adams. The most important stocks for low density planting (LDP) are seedlings and clonal pear rootstocks. The clonal pear rootstocks from the OH×F series include some interesting genotypes like OH×F40 (Farold® 40) in Europe, and OH×F87 (Farold® 87) and OH×F97 (Farold® 97) in the USA. Many training systems are suitable to increase planting density, especially the V and vertical axis systems. The advantage of the V system is a double cropping wall and maximum canopy light interception, while the drawbacks include higher trellis outlays and more laborious pruning due to the complicated trellis structure. New ideas regarding tree shape include plants with 2 or 4 axes to divide the vigour across multiple leaders. Very intensive pruning in pear can enhance fruit set in particular cultivars, such as ‘Abbé Fétel’ and ‘Doyenne du Comice’. Other cultivars like ‘Beurre Bosc’ and ‘d’Anjou’ require long pruning. HDPs require an intensive management program with drip irrigation and localized applications of nutrients to optimize fruit quality. 2-D canopies can improve light efficiency, minimizing the zones of the tree where fruit are born and grown in the shade. Root pruning to control vigour has become a very frequent management tool in HDP orchards.
Musacchi, S. (2021). Physiological basis of pear pruning and light effects on fruit quality. Acta Hortic. 1303, 151-162
DOI: 10.17660/ActaHortic.2021.1303.23
Pyrus communis L., orchard management, rootstocks, training system, pruning

Acta Horticulturae