PHYSIOLOGICAL ASPECTS AFFECTED BY PHOTOSELECTIVE NETS IN APPLES: PRELIMINARY STUDIES
Photoselective nets are an emerging technology that might affect apple tree productivity and fruit quality. However, the physiological aspects involved in these photo-responses are not yet fully understood. The aim of this research was to evaluate the effects of photoselective nets on apple leaf gas exchange. Two-year-old Fuji apple trees grown in 40-L pots were covered with shade or hail nets, according to the following treatments: red shade net (RS), grey shade net (GS), blue shade net (BS), pearl hail net (PH), red hail net (RH). Light transmission (400-800 nm) spectra, leaf net photosynthesis (PN) and net transpiration (E) were measured under nets. Photosynthetically active radiation (400-700 nm) transmission was reduced 20.2% by RH, 12.5% by PH, 41.9% by RS, 46.3% by BS and 56.3% by GS. Spectral composition was unaltered by GS and PH nets, while RH, RS and BS substantially changed the blue:red light proportion. GS, RS and BS nets significantly increased E compared to RH and PH, while under BS, PN was significantly higher than RS, RH and PH. Differences on PN and E under photoselective nets are linked to changes in light quantity, but also in light quality, which probably affect anatomical and morphological aspects. These responses are currently being assessed.
Bastías, R.M., Losciale, P., Chieco, C., Rossi, F. and Corelli-Grappadelli, L. (2011). PHYSIOLOGICAL ASPECTS AFFECTED BY PHOTOSELECTIVE NETS IN APPLES: PRELIMINARY STUDIES. Acta Hortic. 907, 217-220
coloured nets, photomorphogenesis, photosynthesis, M. domestica Borkh