Effect of photo-selective colored anti-hail nets on photosynthesis and quality of apple fruits

Recently, shading nets have been mainly used on apple orchards to avoid hail and sunburn.
In this study, the effects of red, pearl and flue colored photo selective nets (Iridium^®Tenax) on photosynthesis and fruit quality of apple ‘Granny Smith’ were compared with a black shading net, commonly used for orchards, as a control.
The influence of colored nets on net photosynthetic rate (PN: μmol CO₂ m^-2 s^-1), leaf water usage efficiency (WUE: µmol CO₂ mmol^-1 H₂O) were monthly measured from full bloom until harvest.
Incidence of sun scald, fruit flesh firmness, fruit dry weight, peel color, total antioxidant capacity, total phenolic content and possible delay on harvest date were also determined.
Red colored photo selective net and black net, which was used as control, both had a better potential for photosynthetic rate, leaf water usage efficiency, fruit flesh firmness and peel color than pearl and flue nets.
The other mentioned quality parameters had minimal changes between different colored nets.
The harvest date was not delayed in trials, however, there was more sun scald under pearl net than the others.
The results of this study show that red colored photo-selective net can be used for to obtain better photosynthetic rate, leaf water usage efficiency, fruit flesh firmness and peel color comparing with control and other colored nets.

VIII International Postharvest Symposium: Enhancing Supply Chain and Consumer Benefits – Ethical and Technological Issues

O. Özkaya, A. Küden, B. Imrak, Ö. Dündar, H. Demircioğlu, N. Dölek

Malus domestica, crop management, light management, preharvest

https://doi.org/10.17660/ActaHortic.2018.1194.7